Patent GB-861065-A (GB)
Title: Apparatus for use in mixing materials
IPC: B01F15/04
Filed: 1958-01-28
Abstract: 861,065. Mixing materials in definite proportions. TARUKAWA, T. Jan. 28, 1958, No. 2789/58. Class 86 [Also in Group XVIII] An automatic mixing and accumulating apparatus comprises, a measuring tank 1, Fig. 1, for a predetermined amount of a liquid material and measuring tanks 2, 3 for predetermined amounts of powdery materials; a mixing tank 4 having a rotary stirring device 4a therein to receive materials when discharged from the tanks 1, 2 and 3; an accumulator tank 17 to receive the mixed materials when discharged from the tank 4; a first electric limit switch S1 operable in response to a first decrease of a predetermined small amount of the mixed material in the tank 17; and a second electric limit switch S2 operable in response to the second decrease of a predetermined large amount of the mixture; magnets M1, M2 and M3 and a switch Mg operable in response to the operation of the switch S1 to discharge the tanks 1, 2, 3 into the tank 4 and to drive the stirring device 4a by a motor M1 and magnets M4, M5 and switches S3, S4, operable in response to the operation of the switch S2 to discharge the tank 4 into the tank 17. The tank 17 is provided with a float 26 connected by a string 24 with a vertical slidable rod 20 engaging rollers 23 which in turn engage the side of the tank. The rod 20 also engages rollers 29, 30, which are connected to the movable members of the switches S1, S2, so as to maintain the switches "open " against the action of springs 27a, 28a. When the level in the tank 17 falls a first small amount on opening a valve 18, the rod 20 disengages the roller 29 whereafter the switch S1 is closed. Thereafter the circuits of the magnets M1, M2, M3 are energized through a time switch TC2 and the motor switch Mg is closed through a time switch TC1 so that a stirrer 4a is rotated. When the level falls in the tank by a predetermined large decrease of mixture in the tank 17, the rod 20 also disengages the roller 30 whereafter the switch S2 is closed. The magnet M4 is then energized through the switch S3 and a crank 14 provided with a weight 12 is turned counter-clockwise through a string 15 whereby the weight opens the switch S3. The crank 14 is also connected through a linkage 10, 9, 7 to the discharge valve 6 of the mixing tank 6 so that the movement of the crank 14 opens the valve 6 which is then maintained open by the weight 12. At this time the switch S4 is closed owing to the removal of the weight 12 so that the magnet M5 operates after a time lag of a time switch TC3. The magnet M5 pulls a string 16 connected to the crank 14 to return the latter to the position shown and thus close the valve 6. The discharge of the mixture into the tank 14 causes the float 26 to rise so that the switches S2, S1 close in sequence. The time lag of the switch TC3 is so selected as to ensure that the tank 4 is completely discharged. Similarly the time lag of the switch TC2, is sufficient to allow complete discharge of the tanks 1, 2 and 3 whilst the switch TC1 ensures that the motor will be energized for a relatively long time. The tank 17 may be provided with two floats, i.e. upper and lower and both of small movements as described with reference to Fig. 2 (not shown), or have switches S1, S2 operable by membranes moved by the pressure of the mixture thereon as described with reference to Fig. 3 (not shown). Instead of floats of membranes the tank 17 may be supported at one end of a lever balance having a weight at its other end whereby decrease in the amount of the mixture in the tank 17 will cause rotation of the lever balance whereafter cranks are rotated in sequence to open the switches S1, S2, the cranks being subsequently restored by further magnets and a time switch as described with reference to Fig. 5 (not shown). When only powdery materials are to be mixed the tank 17 may be carried on a balance as just described and provided in its bottom with a motor driven conveyer screw to discharge the mixture, as described with reference to Fig. 6 (not shown). In another form of the apparatus (Fig. 8, not shown) the mixing tank is rotatable in opposite directions and a rotary crank and a pair of switches control the direction of rotation of the motor which rotates the tank. In still another form of the apparatus described with reference to Fig. 7 (not shown), the tank 4 is rotated but the stirring device is omitted. The tank 4 is connected by a pivoted shoot to a loading bucket conveyer for the accumulator 17. The shoot is lifted by a cable and shaft driven from an electric motor through a clutch device the latter being disengageable by a magnet so that the shoot can be pivoted to the discharge position under gravity. Referring to Fig. 4, the container 1 for liquid material includes a float 34 connected by a lever 32 controlling an inlet valve 31, the float 34 also being connected to a lever 37 pivoted at 37a and having a weight 37b thereon. The lever 32 is also connected via a chain 35a and lever 35b to a lower and heavier float 35. The lever 37 is also connected by a lever 39 to a pivoted bell crank 41 having a weight 41a. A magnet M1 (shown energized) operates a bell crank 42 connected by a string 38 to a lever 36 pivoted at 36a and provided with a weight 36b, the lever 36 also being connected by a link 40 with a further link 43. The link 43 is pivoted at 43a and connected with a discharge valve 33 and when turned clockwise can lift the float 38 and the valve 33 as shown. The weight of the ball 34 alone, is insufficient to operate the bell crank 41. When the tank 1 is discharged the float 35 falls and forcibly closes the valve 33 and opens the valve 31 the latter being closed when the float 34 rises. Moreover the crank 42 is rotated clockwise. Referring to Fig. 9, the tank 2 or 3 for powdery materials is provided with a discharge door 79 pivoted to the body 78 of the tank at 79a. The door is connected to a wire rope 80 wound on a shaft 81 connected by a clutch 82 to the shaft of a motor m6, the clutch being normally engaged by a spring 84 on the motor shaft and disengageable by a pivoted crank lever 83 operable by a chain 85. When the clutch is disengaged the door opens by gravity, and a pair of electric contacts i, j are opened by the movement of a pin 98 on the door. A switch control member 91 is pivoted in the tank and operable by the pressure of the material thereon to move a contact member 92 from a contact c to a contact d. The tank body 78 is supplied with material from a container 86 by a conveyer screw 87 driven by a motor m7 controlled by a magnet operated switch S16. The motor m6 is controlled by a switch S15 which is opened by a magnet M12. The chain 85 is operable by a magnet M13 which corresponds to the magnet M2 or M3 of Fig. 1, the magnet being operated by the circuit of a magnet M10 as described with reference to Fig. 9A (not shown). When the door is fully open it operates a switch S17 to cause a magnet M14 to move a switch S18 to close contacts 99b and open contacts 99a. Assuming the door is opened the operation is as follows. The switch S15 closes because the magnet M12 is de-energized by the open contacts i, j so that the motor m6 drives the clutch 82 and shaft 81 whereby the door 79 iswound-up to the closed position. Thereafter, with the contacts i, j remade the magnets M11, M12 and excited through a switch S14, contact 92 and contact c. Thus the motor m6 stops and the motor m7 is started to supply material to the body 78. When the material reaches a predetermined level the control member 91 is operated to make the contacts 92 and d whereafter a magnet M11 is deenergized to open the switch S16 and the motor m7 stopped. The switch S15 is maintained open by contacts g, h. The magnet M10 is now excited whereby the bell crank 89 is rotated counterclockwise so that a weight 89b " breaks " the switch S14 to positively ensure that the circuit of the magnet M11 is opened. The operation of the push button S18 energizes a magnet M9 to restore the crank 89 to the position shown.