FEEDING A SOLID-LIQUID MIXTURE

Abstract: A method of feeding a solid-liquid mixture comprised of a liqiud and a solid having a specific gravity greater than that of the liquid comprises depositing the solid around a feed opening (203) disposed at the bottom of a mixing container (202) and feeding the solid-liquid mixture to a device (210) for packing the same. Apparatus comprises a mixing container (202), a feed opening (203) disposed at the bottom of the mixing container, a feed controlling device disposed below or within the feed opening, and a collecting device (230) for depositing the solid component of the mixture around the feed opening (203). The solid-liquid mixture can be fed in a desired constant mixing ratio since the ratio can easily be controlled by simply depositing solid component around the feed opening (203) and changing the cross-section of the flow path at any position from the feed opening (203) to the chute member (204).

Description: The present invention relates to a method of feeding a solid-liquid mixture and an apparatus therefor, for example a method of feeding or dispensing a solid-liquid mixture such as stew, soup, curry and sauce into a container such as packing bags as well as an apparatus therefor. Heretofore, apparatuses for feeding a solid-liquid mixture such as those listed above to a container in a desired mixing ratio and a constant amount have been known. For instance, GB-A-2 146 617 discloses an apparatus in accordance with the preamble of claim 4 in which a solid-liquid mixture is fed to a container while agitating the mixture with paddle blades. However, in such an apparatus, particles of the solid component present in the mixture collide with each other due to the agitation as well as the blades collide with the solid particles. As a result, the solid particles are damaged and are destroyed. Moreover, bubbles are formed in the solid-liquid mixture depending on the rotational speed of the blades, which leads to a lowering of the commercial value of the resultant goods and the reduction of the precision in the metering of the mixture during filling. In addition, there is known another apparatus for feeding or dispensing a solid-liquid mixture into a container in a desired mixing ratio, in which the solid-liquid mixture is agitated by blowing air into the solid-liquid mixture. However, in this apparatus it is difficult to prevent the solid components from colliding with each other, which leads to the destruction of the solid component, and the formation of bubbles in the mixture is a more severe problem as compared with the aforementioned apparatus provided with blades for agitation. The present invention provides a method of feeding a mixture composed of at least one liquid component and at least one solid component having a specific gravity greater than that of the liquid component into a container, the method comprising depositing the solid component in the vicinity of a feed opening disposed at the bottom of a mixing container and feeding the solid-liquid mixture through the feed opening to a container, such as a packing bag. According to another aspect the present invention provides an apparatus for feeding a solid-liquid mixture comprised of at least one liquid component and at least one solid component having a specific gravity greater than that of the liquid in a desired mixing ratio which comprises a mixing container, a feed opening disposed at the bottom of the mixing container, and a feed controlling device disposed below or within the feed opening, characterised in that it further comprises a collecting device disposed in the mixing container for depositing the solid component of the mixture around the feed opening. The area of the feed opening may be adjustable . In the accompanying drawings, apparatus disclosed with reference to Figures 1 to 7 does not represent apparatus according to the invention, only Figures 8 to 19 relate to apparatus according to the invention: Figure 1 is a sectional view illustrating a first type of apparatus for feeding a solid-liquid mixture; Figure 2 is a sectional view illustrating a part of a second type of apparatus for feeding a solid-liquid mixture; Figure 3 is a sectional view illustrating a part of a third type of apparatus for feeding a solid-liquid mixture; Figure 4 is a schematic plan view of the apparatus shown in Figure 3; Figure 5 is a sectional view illustrating a fourth type of apparatus for feeding a solid-liquid mixture; Figure 6 is a sectional view illustrating a fifth type of apparatus for feeding a solid-liquid mixture; Figure 7 is a sectional view illustrating a sixth type of apparatus for feeding a solid-liquid mixture; Figure 8 is a sectional view illustrating a seventh type of apparatus for feeding a solid-liquid mixture; Figure 9 is a graph showing the solid-liquid ratio observed in Test Example 1; Figure 10 is a graph showing the solid-liquid ratio observed in Test Example 2; Figure 11 is a perspective view of another apparatus for feeding solid-liquid mixtures; Figure 12 is a perspective view of a collecting device; Figures 13 to 15 are diagrams illustrating the functions of the first piston device and the second piston device; Figure 16 is a schematic plan view of a collecting blade; Figure 17 is a side view of a screw type collecting blade; Figure 18 is a side view of a ribbon-like collecting blade; and Figure 19 is a side view of a paddle type collecting blade. Figure 1 shows apparatus which comprises a bowl shaped container 1 for mixing a solid-liquid mixture M, a feed and shut-off device 2 for feeding and shutting off the mixture contained in the container 1, which is disposed at the bottom of the container 1 and a feed controlling device 4 for adjusting the minimal sectional area of the path for feeding the mixture M therethrough and disposed below the feed and shut-off device 2, the feed controlling device 4 being connected to a known filling device 6. The internal surface of the mixing container 1 is constituted by a part of a spherical surface. However, it is also possible to constitute the surface thereof by a member in the form of an inverted truncated cone provided with a feed and shut-off device 2 at its lower narrower end. The feed and shut-off device 2 comprises a shut-off plate 10 which is inserted in and withdrawn from a feed path 12. The feed controlling device 4 is constructed so that a plurality of plates 16 each having a through hole 14 of a different size, which are previously prepared, can be selectively inserted into the feed path 12 from one side of the feed path. Using such an apparatus of the foregoing construction, a liquid component 20 is mixed with a solid component 22 of a specific gravity greater than that of the liquid in the mixing container and the solid component 22 is deposited on the bottom of the mixing container. At this stage, the shut-off plate 10 is withdrawn from the feed path 12 while inserting a selected plate 16 having an opening 14 of a desired size into the feed path 12. Thus, the liquid component 20 and the solid component 22 deposited on the bottom of the container 1 are transferred to a filling or dispensing device 6 through the feed path 12 while maintaining a desired mixing ratio of the mixture. The types of apparatus shown in Figs.2 to 7 are explained simply on the basis of the mixing container 1 and a feed controlling device, and the explanation and the diagramatic representation of the feed and shut-off device 2 and the filling or dispensing device 6 which are common to the apparatus shown in Fig. 1 and other apparatuses are omitted. In Figure 2 a feed controlling device 30 is constructed so that the feed amount and the mixing ratio of the mixture M can be controlled by adjusting the position of the feed controlling plate 32 to be inserted into the feed path 12. The insertion of the feed controlling plate 32 into the path is achieved by the reciprocating motion or the rotational motion of the feed controlling plate 32 within a plane perpendicular to the feed path 12. In Figs. 3 and 4, a feed controlling device 40 comprises a rotatable plate 44 having a plurality of through holes 42 of different diameters, formed on the same pitch circle and provided with a handle 46. In this respect, any one of the circular holes 42 may selectively be located within the feed path 12 by rotating the handle 46. In Figure 5 a feed controlling device 51 is constructed so that a plurality of plates 52 previously prepared, each having a through hole 50 of a different area, may selectively be inserted into the feed path 12 from inside the mixing container 1. In this apparatus, it is desirable that the feed and shut-off device be placed below the feed controlling device 51. In Figure 6, a feed controlling device 61 is provided with a plurality of plates 62 each having a through hole 60 of a different area, as in the apparatus shown in Figure 5. The plates having through holes are arranged at the side of the feed path 12 while they are superposed on one another and are constructed so that any one of them can be selectively inserted into the feed path 12. In Figure 7, a feed controlling device 71 comprises a cylindrical member 70 having a plurality of circular through holes 72, each being perpendicular to the axial line 73 of the cylindrical member and which are formed within the same cross-section thereof. The cylindrical member is engaged with the feed path 12 so as to be able to freely rotate around the axial line 73. The minimal cross section of the feed path 12 is determined by selecting any particular through hole 72 and arranging it so as to be parallel to the feed path 12. In another apparatus, not shown, a feed controlling device comprises a flexible tube constituting a part of the feed path and a adjustable clamping device disposed outside the flexible tube. The mixing ratio of the mixture is controlled and/or adjusted by changing the size of the minimal cross section of the flexible tube for feeding the mixture therethrough, which is effected by operating the clamping device. In a further apparatus, not shown, a feed controlling device comprises a variable throttling device like an iris located within the feed path. If the variable throttling device is one capable of complete shut-off of the feed path, the use of the feed and shut-off device may be omitted. The mixing ratio may be controlled by adjusting the degree of throttling of the variable throttling device. In Figure 8 a cylindrical container 100 is installed horizontally. In this apparatus, there are disposed, on the upper side thereof, a solid-liquid inlet opening 102 for introducing a solid-liquid mixture into the cylindrical container 100 and a sight through window 104 for observing the interior of the container 100. There is disposed, on the lower side thereof, a solid-liquid outlet opening 106 for transferring the mixture, the outlet opening communicating with the feed controlling device (not shown). Within the container 100, a rotary shaft 108 having an axis coincident with the axial line of the mixing container is placed and two groups of collecting blades 110 and 112, each comprising two blades, are disposed around the shaft symmetrically with respect to the center of the solid-liquid outlet opening 106. A collecting device 114, comprised of the rotary shaft 108 and the collecting blades 110 and 112 fixed around the shaft, is rotated at a relatively low speed by the action of a driving device (not shown) and thus the solid component of the mixture deposited on the bottom of the container can be moved along the bottom surface of the container without any floating or flying about of the particles whereby the particles are collected on the solid-liquid outlet portion 106 or in the vicinity thereof. Test Example Using an apparatus having a construction similar to that shown in Figure 8, the variation in the mixing ratio of the charged solid-liquid mixture, in this case a mixture of water and soybean which has been immersed in water over night (the major axis of the soybean being about 7 to 10mm), was examined while selecting a circular hole of 76.2 mm in diameter as the minimal cross section of the feed controlling device, through which the mixture is transferred. Test No. 1 Solid-Liquid Ratio (by weight) in the Mixing Container 56 : 44 Net weight Charged (average) 410.7 g The results observed are plotted in the graph shown in Fig. 9 with the number of filling operations as abscissa and the weight as ordinate. In Fig. 9, A is the net weight of the mixture charged and B is the weight of the solid component charged. Test No. 2 Solid-Liquid Ratio (by weight) in the Mixing Container 42 : 58 Net weight Charged (average) 404.5 g The results observed are shown in Fig. 10. The apparatuses for feeding a solid-liquid mixture to a filling device will hereunder be explained in more detail with reference to Figures 11 to 19 of the accompanying drawings. The apparatus shown in Figure 11 comprises a mixing container 202 of approximately cylindrical shape, a discharge or chute member 204 mounted at a feed opening 203 portion disposed at the bottom of the mixing container 202, a first piston device 206 connected to the lower portion of the chute member 204, a second piston device 208 connected to the first piston device 206 at one side and a filling or dispensing device 210. The mixing container 202 is provided with, on the top thereof, a level gauge 222 for determining the height of the liquid level of the solid-liquid mixture in the container and a sight through window 224 for observing the interior of the container therethrough, and, on the upper side thereof, a tube 226 for feeding the solid-liquid mixture into the mixing container. As shown in Figs. 11 and 12, a collecting device 230 is installed within the mixing container 202 and the device comprises a shaft member 229 on which four collecting blades 228 are disposed. The shaft member 229 has an axis in common with the mixing container 202 and is disposed within the container in a freely rotatable manner, and is rotated by the operation of a driving device (not shown). The collecting blades 228 are divided into two groups each comprising two blades and these two groups of collecting blades are mounted on the shaft symmetrically with respect to the feed opening 203 so as to form spirals having orientations opposite to one another. Figure 16 shows the shaft member 229 which is arranged to rotate about its longitudinal axis L as indicated by the arrow, that is clockwise when viewed from the right hand end. One of the collecting blades 228 is arranged to the left of the feed opening 203 and extends perpendicular to a plane which is parallel to be flat sheet of the drawing and which includes the longiduitnal axis L. The collecting blade 228 forms an angle ϑ with the longitudinal axis L of the shaft member 229, which angle ϑ satisfies the condition 0° < ϑ < 90°. The solid component of the mixture is gradually moved along the bottom surface of the mixing container 202 and transferred towards the feed opening 203 by arranging the collecting blade 228 is such a manner as described above. As desired examples for the construction of the collecting blades 228, there may be mentioned such a screw type one as shown in Fig. 17, such a helical ribbon type one as shown in Fig. 18 and such a paddle type one as shown in Fig. 19. The screw type collecting blade provides various advantages: (1) it can transfer the solid component to the filling device even if the rotational speed is substantially low and (2) it is possible to restrict the occurrence of damage to the solid component since the blades, in this case, is comprised of a continuous one. If a ribbon type or paddle type collecting blade is used, it is necessary to increase the rotational speed thereof in order to achieve a desired movement or transfer of the solid component. However, these types of blades exhibit advantages in that they may easily be processed to desired shapes and thus the manufacturing cost thereof is quite low. In Fig. 12, the collecting blades 228 are arranged along a spiral locus at equal intervals and thus they make it possible to transfer the solid component at an equal speed over the whole portion of the mixing container 202. Moreover, the collecting blades 228 should not be mounted on the upper portion of the feed opening 203. This is because the deposits of the solid component are disturbed in the vicinity of the feed opening 203 due to the rotation of the collecting blades 228 and thus becomes unstable. However, if the chute member 204 of relatively great depth is used, it is not necessary to restrict the region at which the collecting blades 228 are disposed since the solid components are always deposited on the chute member 204 stably. The radius of the collecting blades 228 are determined so that the distance between the apex thereof and the internal surface of the mixing container 202 is as close as possible. This is required to ensure collection of the solid component by the collecting device 230. The chute member 204 is in general formed in a cylindrical shape or a funnel like shape and it may be integrally formed together with the mixing container 202 as a part thereof. If the collecting blades 228 are mounted on the shaft member 229 approximately perpendicular with respect to the latter the solid component is not paddled by the collecting blades 228 towards the upper portion of the mixing container 202 and in turn the solid component is not damaged and destroyed due to the collisions therebetween. The first piston device 206 comprises, as shown in Figs. 13 to 15, a device 242 for switching flow paths and a first piston 244 provided with a first piston member 243. The flow path switching device 242 is provided with an inlet portion 240, a piston communicating portion 246 and a delivery portion 248, and there is disposed a switching member 250 at the communicating portion common to these three portions. The switching member 250 may be located at either the position at which the inlet portion 240 and the piston communicating portion 246 are communicating with one another, as shown in Fig. 13; or the position at which the piston communicating portion 246 and the delivery portion 248 are communicating with one another as shown in Figs. 14 and 15. The second piston device 208 comprises a cylinder 260 provided with a tube 262 for communicating the cylinder with the delivery portion 248 of the first piston device 206. The position at which the communicating tube 262 is connected to the cylinder 260 is determined so that the communicating tube 262 is opened to communicate the tube 262 with the filling device 210 when a second piston member 264 is situated at the upper portion as shown in Fig. 14 and that, on the other hand, it is closed when the second piston member 264 is situated at the lower portion as shown in Figs. 13 and 15. The filling device 210 fills, into packing bags 270, a desired amount of the solid-liquid mixture transferred from the second piston device 208 and then seals the opening 272 of the packing bag for finishing a cycle of the packing operation of the mixture. The function of the apparatus for supplying solid-liquid mixture having the foregoing construction will hereunder be explained. The solid-liquid mixture is introduced into the mixing container 202 through the tube 226. In the mixing container 202, the shaft member 229 is rotated at a relatively low speed to collect the solid material around the inlet portion of the chute member 204 and to deposit the solid material within the chute member 204. The rotational speed is determined so that the solid material does not fly about from the bottom of the container by the rotation of the shaft member 229 and it is slowly moved along the bottom surface and transferred towards the chute member 204. As shown in Fig. 13, the piston member 243 of the first piston device 206 is moved back so that the inlet portion 240 and the piston communicating portion 246 communicated with one another and a desired volume for receiving the material is assured and filled by the solid-liquid mixture. Subsequently, the switching member 250 is rotated so as to communicate the piston communicating portion 246 and the delivery portion 248, as shown in Fig. 14 and thus the first piston member 243 advances to transfer, under pressure, the solid-liquid mixture present in the first piston device 206 to the second piston device 208. In the second piston device 208, as shown in Fig. 14, the second piston member 264 ascends to communicate the tube 262 with the packing bag 270 and thus a part of the solid-liquid mixture is packed into the packing bag 270. Then, as shown in Fig. 15, the second piston member 264 descends so that the solid-liquid mixture present in the second piston device 208 is further packed in the packing bag 270 until a desired amount of the mixture is finally filled therein. The aforementioned operations of the first and second piston devices 206 and 208 are repeated and the packing bags 270 are also continuously supplied one by one thereby the filling of the mixture into the packing bags being continuously effected. The adjustment of the mixing ratio of the solid-liquid mixture can be effected by selectively placing, between the chute member 204 and the inlet portion 240 in the device for switching the flow paths, a throttling plate selected from those having various openings of different sizes. Moreover, the adjustment of the mixing ratio of the solid-liquid mixture may also be effected by changing the cross-section of the flow path of the chute member 204, through which the solid material is transferred, or that of the opening 203 for feeding. Thus, in a method of feeding a solid-liquid mixture which comprises introducing a solid-liquid mixture into a mixing container, depositing the solid component of the mixture around an opening for feeding mixture, disposed on the bottom portion of the container and feeding the mixture through the opening, it is possible to change the mixing ratio of the resultant mixture by adjusting the area of the opening for feeding. Therefore, the method exhibits a variety of advantages such that the construction thereof is very simple, the solid component is not damaged and destroyed and a desired and constant mixing ratio can certainly be maintained. In addition, the apparatus makes it possible to feed the solid component deposited around the opening for feeding together with the liquid component in a desired constant mixing ratio, this is because the apparatus makes it possible to adjust the mixing ratio of the mixture by simply changing the cross-section of the flow path at any position from the opening for feeding to the chute member.

Claims: A method of feeding a solid-liquid mixture comprised of at least one liquid component (20) and at least one solid component (22) having a specific gravity greater than that of the liquid component, the method comprising depositing the solid component(22) in the vicinity of a feed opening (203) disposed at the bottom of a mixing container (100, 202) and feeding the solid-liquid mixture through the feed opening to a container (6, 210). A method according to claim 1, characterised in that the feeding of the solid-liquid mixture is effected while adjusting the mixing ratio of the mixture by changing the area of the opening (14, 42, 50, 60, 72) for feeding. A method according to claim 1 characterised in that the feeding of the solid-liquid mixture is carried out at a constant mixing ratio which is adjusted by changing the minimum cross-section of the feeding path (12, 106, 204) communicating with the opening (203) for feeding. An apparatus for feeding a solid-liquid mixture comprised of at least one liquid component (20) and at least one solid component (22) having a specific gravity greater than that of the liquid in a desired mixing ratio, which comprises a mixing container (100, 202), a feed opening (203) disposed at the bottom of the mixing container, and a feed controlling device (4, 30, 40, 51, 61, 71) disposed below or within the feed opening (203), characterised in that it further comprises a collecting device (114, 230) disposed in the mixing container (100, 202) for depositing the solid component of the mixture around the feed opening (203). An apparatus according to claim 4, characterised in that the area of the feed opening (203) is adjustable. An apparatus according to claim 4 or 5, characterised in that the opening (203) communicates with a discharge member (106, 204). An apparatus according to claim 6, characterised in that the cross-section of the opening of the discharge member (106, 204) is adjustable. An apparatus according to anyone of claims 4 to 7, characterised in that the collecting device (114, 230) is provided with collecting blades (110, 228). An apparatus according to claim 8, characterised in that each collecting blade (228) is mounted on a shaft member (229) and extends perpendicular to a plane which includes the longitudinal axis (L) of the shaft member (229) and forms an angle (ϑ) with the longitudinal axis (L) of between 0° and 90°. An apparatus according to claim 8, characterised in that the collecting blades (228) are each in the form of a screw (Figure 17). An apparatus according to claim 8, characterised in that the collecting blades (228) are each in the form of a helical ribbon (Figure 18). An apparatus according to claim 8, characterised in that the collecting blades (228) are each in the form of a paddle (Figure 19). An apparatus according to any one of claims 8 to 12, characterised in that the collecting blades are disposed in regions except for that just above the feed opening (203).

Inventors: IWATA, HITOSHI, NAKATANI, MASAYUKI, NAMBA, KATSUAKI, SAWADA, HIROSHI
Applicants: HOUSE FOOD INDUSTRIAL CO., LTD.
Application year: 1987
Main classification: B65B37
IPC codes: B65B37