Abstract:
A machine including a container fitted with a base that extends between lateral walls and end walls. The base partially covers (i) a mixing rotor and (ii) a feed auger which moves products in the skip either in a closed circuit or in a circuit towards a distributing chute. A transfer screw is mounted on top of the feed auger. The transfer screw can include cutting members in the form of sectioning parts. The sectioning parts co-operate with teeth which are disposed on a beam. The teeth can be positioned as necessary either on a beam located in the container or on one or more beams located on the lateral wall. Similarly, the feed auger can also include sectioning parts that co-operate with teeth if required.

Description:
BACKGROUND OF THE INVENTION 
   This present invention relates to a mixing machine for distribution of product for feeding cattle. 
   DESCRIPTION OF THE RELATED ART 
   This type of machine, described particularly in document U.S. Pat. No. 3,672,640, consists of a skip open on the top; this skip comprises a rotor with large diameter extending longitudinally between the end walls and which is partially surrounded by a rounded bottom in the form of a trough. This rotor stirs and mixes the product which it propels gradually towards an endless screw arranged laterally, parallel to said rotor and whereof the diameter is three to four times smaller than that of the latter. 
   This lateral screw also extends between both end walls and it is also surrounded partially by a bottom in the form of a trough; it moves continuously and longitudinally the product from one end to the other of the skip toward the end thereof where lies the feeding orifice so that, when this orifice is closed by an appropriate flap, the product are moved in the skip, as a closed circuit, and are stirred thanks to the mixing rotor. 
   The document EP-498 543 describes a machine such as that detailed above with, in addition, a transfer and cutting screw, which enables to incorporate products, such as hay or straw in the skip. 
   This transfer screw whereof the diameter is substantially the same as that of the mixing screw mentioned above, is arranged above the latter, rotating in the same direction but with a reverse propeller pitch. 
   This transfer screw comprises, on its periphery, knives or sections which enable to drive and, to a certain extent, to cut hay or straw. 
   This hay or straw is deposited in batches on top of the transfer screw, in a kind of hopper or funnel formed by shutters. 
   For certain types of product and in particular hay, the cutting means of the document mentioned above prove vastly insufficient. 
   It is known, as described in the document GB-2 283 898, for another type of mixing machine, to associate a single mixing rotor, with large diameter, in the form of a screw provided with knives on its periphery, with a shutter whereof the edge close to said screw is provided with teeth. The knives of the screw and the teeth may enable to cut the product and in particular straw or hay. 
   But the presence of knives on the periphery of the screw reduces accordingly the efficiency thereof in order to move the product on the bottom of the skip. 
   Moreover, for a screw of such a diameter, the driving loads are very high and are made even worse by the presence of knives and of teeth forming counter-knives. 
   SUMMARY OF THE INVENTION 
   The present invention provides a feeding mixing machine comprising means which enable efficient cutting of the product, such as hay or straw and in particular all types of hay. 
   The present invention also provides an arrangement of the skip at the inlet area of hay or straw bales. The product may indeed accumulate and there may be jams between both screws, when hay or straw bales are injected on the transfer screw. 
   These phenomena are due to the fact that the feeding screw comprises, at the feeding orifice, a neutral area where its propeller is replaced with tangential propulsion vanes. Beyond this neutral area, i.e. close to the end wall, the propeller of the screw has a reverse pitch, in order to bring the product back onto the orifice. 
   Thus, when the feeding screw operates as a recycling screw, the product accumulates at the neutral area and run up towards the transfer screw which may already be overloaded by the presence of hay or straw bales. 
   The present invention enables to obviate these drawbacks. 
   The machine according to the invention comprises, on one at least of the transfer screws and/or feeding screws, knives in the form of sections, arranged by couples, forming a V, each couple co-operating with teeth arranged on a support in the form of beam for instance, which beam extends at a distance from the casing of the screw provided with said knives, between the end walls of the skip. 
   Still according to the invention, the couples of sections are distributed over the length of the screw, arranged in a radial plane on a particular arrangement of the periphery of the propeller, or mounted on an appropriate support provided behind the active surface of said propeller, integral with the screw. 
   Still according to the invention, the couple of sections is in the form of a V whereof the angle is of the order of 10 to 45°, co-operating with teeth which are for instance in the form of a triangle or trapezoid having the same angle as said V. 
   According to another embodiment of the invention, the number of couples of sections per screw turn is three to six for instance and these couples are spaced longitudinally by a distance of the order of 5 to 15 cm and their effective working height is of the same order. 
   According to another embodiment of the invention, the teeth forming counter-knives are made in all or in part of a steel sheet band, which band is fixed on the support in the form of a beam. 
   According to another feature of the invention, the couples of sections are arranged on the transfer screw, co-operating with teeth which are arranged on a beam extending between the end walls of the machine, which beam lies inside the skip, substantially at the intersection of a vertical plane tangent to the casing of the transfer screw on the side of the mixing rotor, and of a horizontal plane which is tangent to the upper portion of said casing of the transfer screw. 
   Still according to the invention, the couples of sections may also co-operate with teeth arranged on at least one support in the form of a beam extending on the lateral wall of the skip close to the transfer screw, which support is arranged substantially at the intersection of said lateral wall with a horizontal plane tangent to the upper portion and/or the lower portion of the casing of the transfer screw. 
   Still according to the invention, the couples of sections are arranged at the feeding screw, in combination or not with the sections arranged as detailed previously on the transfer screw, which sections are distributed over the length of said feeding screw co-operating with teeth arranged on a beam made at the junction of the respective portions of the bottom surrounding on the one hand said feeding screw and on the other hand the mixing rotor, which couples of sections are also able to co-operate with teeth arranged on a support in the form of a beam integral with the lateral wall of the skip, arranged at the intersection thereof with a horizontal plane tangent to the upper portion of the casing of said feeding screw. 
   Still according to the invention, the machine comprises, above the transfer screw, an arrangement in the form of a hopper enabling to inject the product and in particular the straw or hay bales, which hopper is arranged in an area located between the neutral area of said transfer screw and the neutral area of the feeding screw. 
   Still according to the invention, the hopper is delineated by the lateral wall of the skip, on the side of the transfer and mixing screws, and by a shutter which is hinged on the beam serving as a support for the teeth, which beam extends between the end walls of the skip, between the transfer screw and the mixing rotor, which shutter is associated with a control member, such as an actuator, in order to be tilted either by the mixing rotor to guide the bales of product on the transfer screw, or be tilted on the side of said transfer screw to guide the product towards said mixing rotor. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be detailed further using the following description and the appended drawings, given for exemplification purposes, wherein: 
       FIG. 1  is a cross sectional diagrammatical view of a feeding mixing machine according to the invention, showing the location of the mixing rotor and that of the lateral screws; 
       FIG. 2  is a partial perspective view of a screw provided with couples of sections, co-operating with teeth; 
       FIG. 3  is a front view showing the position of a couple of sections on the screw with respect to a tooth mounted on a support; 
       FIG. 4  represents a mounting variation of a couple of sections on the periphery of the propeller of a screw; 
       FIG. 5  shows the different possibilities of installation of the teeth which co-operate with the sections installed on the transfer screw; 
       FIG. 6  also shows diagrammatically the teeth co-operating with couples of sections mounted additionally on the mixing screw; 
       FIG. 7  shows the arrangement of the skip with a hopper to facilitate and guide the injection of the product, such as hay or straw bales; 
       FIG. 8  is a view according to section  8 — 8  of  FIG. 7 ; 
       FIG. 9  is a partial top view of  FIG. 8 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The feeding mixing machine is as that which is described in the document EP-498 543 mentioned above, and only the portions useful to the understanding of the invention are detailed hereunder. 
   This machine comprises a skip  1  in the form of a tank, open on the top, delineated by a bottom  2 , lateral walls  3  and  4  and end walls  5  and  6  as represented on the different figures. 
   The bottom  2  comprises two portions  7  and  8  in the form of troughs of different radius. The radius of the portion  8  is of the order of three to four times smaller than that of the portion  7  and both these portions joining while forming a ridge  9 . 
   The bottom  7  constitutes the partial casing of a mixing rotor  10  extending longitudinally between the end walls  5  and  6 . The bottom  8  surrounds a screw  11  partially extending parallel to the mixing rotor  10 . This screw  11  has a diameter which is three to four times smaller than that of the rotor  10  and its upper periphery lies substantially at the same level as the pin of the rotor  10 . 
   A second screw  12  extends above the screw  11 , parallel, and this screw has a diameter which corresponds substantially to that of said screw  11 . 
   The rotor  10  stirs and mixes the product arranged in the skip  1 . It propels the product towards the screw  11 . This screw  11  moves the product from one end to the other of the skip, from the back to the front for instance for recycling purposes and a closed circuit mixing. This screw  11  also enables to feed the product by means of an orifice provided at the feeding chute  13 . 
   This orifice is normally blanked off by a flap, as detailed below in connection with  FIG. 8 . 
   The upper screw  12  revolves in the same direction as the mixing screw  11  but the pitch of the propeller is reversed. This screw  12  transfers the product from the front to the back for instance, unlike the screw  11 , to circulate the product in the skip and improve the mixture. 
   This machine enables to mixing foodstuffs of all kinds and it may also receive products, such as straw or hay. 
     FIG. 2  shows a screw corresponding indifferently to the feeding screw  11  or to the transfer screw  12 , provided with knives which co-operate with teeth  16 . These knives are for instance made of sections  15  arranged by couples at the periphery of the propeller designated  111  for the screw  11  and  121  for the screw  12 . In average, the couples of sections are three to six in number per screw turn. These couples of sections  15  are centred on radial planes and the distance between two adjacent radial planes is of the order of 5 to 15 cm for instance. 
   The height of the sections  15  and their protrusion with respect to the casing of the propellers of the screw are also of the order of 5 to 15 cm and correspond to those of the teeth  16 . 
   The couples of sections  15  may be arranged, as represented on  FIGS. 2 and 3 , on an independent support  17  arranged in a radial plane at the back of the active portion of the propeller or, as represented on  FIG. 4 , on a particular arrangement of the peripheral rim of the propeller. 
   As represented on  FIGS. 2 and 3 , the couples of sections  15  are fixed by bolts  18  for instance on the support  17 . This support  17  is in the form of a plate integral with the hub of the corresponding screw  11  or  12 , and also with the back of the propeller  111  or  121 . 
   The couple of sections  15  forms a V whereof the angle is of the order of 10 to 45° for instance. This couple of sections  15  co-operates each with a tooth  16  which is associated with a support  19  detailed below. 
   These teeth  16  are for instance in the form of triangles or of trapezoids to co-operate with the couples of sections  15 . As represented on  FIG. 3 , the shape of the teeth corresponds with the V formed by a couple of sections  15 . The clearance is relatively small. 
   These teeth  16  are for instance cut into a steel blade which comprises in all or in part teeth necessary to screws. 
   These teeth  16  are preferably part of a band  20  which is fixed by appropriate means on the supporting beam  19 . 
   The embodiment of  FIG. 4  shows a couple of sections  15  co-operating with teeth  16  in the form of simple fingers. These teeth  16  are arranged on a support  19  serving as a beam. 
   Still on  FIG. 4 , the sections  15  also form a V centred in a radial plane of the screw running through the corresponding tooth  16 . The peripheral rim of the propeller  111  or  121  of the corresponding screw, is straightened locally, i.e. it comprises a section  21  which lies in a radial plane, followed by a section  22  which provides a solution of continuity for connecting said section  21  to the peripheral rim of said propeller. 
   These screws  11  and/or  12  provided with couples of sections  15  may co-operate with teeth placed in several locations in the skip. 
   Thus, on  FIG. 5 , the transfer screw  12  is provided with knives in the form of couples of sections  15  and these couples of sections co-operate with teeth  16 . 
   These teeth  16  may be arranged on a beam ( 19 ),  191 , extending between the end walls  5  and  6  of the skip. This beam  191  is situated in the skip same, substantially at the intersection of a vertical plane tangent to the periphery of the transfer screw  12 , on the side of the mixing rotor  10  and of a horizontal plane tangent to the upper periphery of said screw  12 . 
   To suit the requirements, the teeth  16  may also be arranged on the side of the wall  4  on a beam ( 19 ),  192  diametrally opposite to the beam  191 . This beam  192  forms, in addition, a kind of reinforcement for the wall  4 . 
   Still on  FIG. 5 , one may notice the presence of a beam ( 19 ),  193  arranged against the lateral wall  4  at the same level as the beam  191 . This beam  193  may also be provided with knives  16  which co-operate with the couples of sections  15 . 
   Thus, to suit the requirements, the machine may be fitted with one or several sets of knives arranged either on a beam inside the skip, or on one or several beams installed against the lateral wall  4 . 
   Still on  FIG. 5 , the delivery screw  11  is in the form of a simple screw with a propeller whereof the contour is smooth simply to move the product on the bottom  8 , from one end of the skip to the other. 
     FIG. 6  shows the adaptation of couples of sections  15  on the feeding screw  11 . These couples of sections may co-operate with teeth  16  arranged on a beam ( 19 ),  194  situated on the internal face of the wall  4 . The couples of sections  15  may also co-operate with teeth  16  arranged on a beam ( 19 ),  195  formed by a particular arrangement at the junction of the bottoms  7  and  8 . 
   Thus, the feeding screw  11  and the transfer screw  12  may be used to cut straw and/or hay at will. 
     FIG. 7  shows a particular arrangement of the upper portion of the skip which enables to promote the guiding of straw or hay bales at its upper portion, either towards the transfer screw  12  or towards the mixing rotor  10 . 
   The beam  191  carries a shutter  25  which is hinged by means of a pin  26  on said beam. This shutter  25  is mobile around its pin  26  under the effect of an actuator  27  which is for instance integral with the end wall  5  or  6  by means of a pin  28  and with said shutter  25  by means of a crank  29 . 
   This shutter, as represented on  FIG. 7 , may tilt on the mixing rotor  10  to facilitate the injection of hay or straw bales on the transfer screw  12  or be tilted thereon as represented as thin dotted lines, in order to facilitate the injection of the product on the mixing rotor  10 . 
   Still on  FIG. 7 , a particular arrangement of the upper portion of the lateral wall  4  can be noticed. This upper portion  31  of the wall  4  is raised and tilted towards the outside in order to form with the shutter  25  a kind of hopper or funnel the better to accommodate and guide the hay or straw bales on the transfer screw  12 . 
   The injection of hay or straw bales in the skip, on the transfer screw  12 , may cause jams. 
   During the preparation and mixing phase of the product in the skip, said product circulates continuously in said skip, under the effect of the mixing rotor  10  and especially of the feeding screw  11  which moves this product of the wall  6  towards the wall  5  and in particular towards the orifice  32 . This orifice  32 , which enables to feed the product by the chute  13 , is normally masked by a flap  33 . At this orifice  32 , a neutral area on the screw  11  can be noticed which is centred on a radial plane  34 . The end portion of the screw  11 , by the wall  5 , comprises a propeller  111 ′ whereof the pitch is reversed with respect to the propeller  111  extending over the whole remainder of the length of the screw. 
   In this neutral area of the screw  11 , between the propellers  111  and  111 ′ radial paddles  37  can be found, which propel the product towards the outlet orifice  32 . This neutral area lies opposite the outlet orifice  32 , which orifice is also centred on the radial plane  34  of the screw  11 . 
   The product has a natural tendency to be driven up towards the transfer screw  12  at the neutral area of the screw  11  when the flap  33  is in normal blanking position of the orifice  32 . Thus, the introduction of the bales of product in the skip at this neutral area i.e. at the plane  34 , may generate disorders, such as jams. 
   The inlet area of the product on the transfer screw  12 , is located preferably outside the neutral area of the feeding screw  11 . 
   The transfer screw  12  may also comprise, at its end located on side of the wall  6 , a neutral area centred on a radial plane  38  and, beyond this neutral area on the side of the wall  6 , comprise a propeller  121 ′ whereof the pitch is reversed with respect to that of the propeller  121 . 
   This neutral area of the screw  12  may, as for the screw  11 , comprise radial paddles  39 . 
   The inlet hopper of the product on the screw  12 , whereof one of the walls is formed by the shutter  25 , extends preferably in an area delineated by the median plane  34  of the neutral area of the screw  11  and the end of the transfer screw  12  or the median plane  38  of the neutral area of said screw  12 . 
   It can be noticed on  FIGS. 8 and 9 , that the transfer screw  12  comprises couples of sections  15  which co-operate with teeth  16  arranged on the beam  191  which carries the shutter  25 . These teeth  16  may for instance co-operate with the larger portion of the propeller  121  as represented on  FIG. 9  whereas the smaller portion of the propeller  121 ′, on the side of the end wall  6 , may comprise sections and co-operate with teeth  16  arranged on the beam  193  for instance.