ROTARY DISC MIXING APPARATUS

Abstract: A mixing apparatus for mixing delicate materials, comprises a vessel (48) for containing a quantity of material to be mixed, a support (12) associated with the vessel, a mixing rotor (14) mounted on the support means for positioning in the vessel, the rotor comprising a rotatable shaft, a plurality of circular discs (20), each having an aperture (30) in a center thereof, and means (26, 38) for mounting the discs on the shaft in axially spaced relation for enabling liquid to flow into the center of the discs and outward between the discs, and a motor (56) drivingly connected to the rotor (14) for rotating the rotor.

Description: ROTARY DISC MIXING APPARATUS REFERENCE TO RELATED APPLICATIONS This is a continuation-in-part of application S.N. 09/022,161 filed february 1 1. 1998, entitled "ROTARY DISC MIXER APPARATUS AND METHOD". TECHNICAL FIELD The present invention relates to mixing apparatus and pertains particularly to an improved rotary disc mixer. Many manufacturing and other processes require the mixing of various liquids and materials in liquids. The traditional mixer is a rotating paddle arrangement mounted on a shaft and rotating about a vertical axis in a large vessel. In this arrangement a vertically mounted rotating shaft carries a plurality of paddles extending radially outward on arms disposed about the axis of the shaft. The rotating shaft moves the paddles through the liquid as the shaft rotates, stirring the liquid and thoroughly mixing materials therein. The paddle system is satisfactory for many applications. However, there are man> delicate and fragile materials that can be easily damaged which cannot be mixed in this manner. The moving paddles can impact and bruise or otherwise damage to the delicate and fragile materials. Another material which cannot be satisfactorily mixed with the typical paddle mixer is highly viscous materials and materials having fibers and the like therein. These materials can build up on the paddles and can inhibit or resist turbulent flow necessary for thorough mixnm. Another class of materials which are not suitable for mixing with paddle mixers is highly abrasive materials. Such materials wear away the paddles at a rapid rate resulting in costly down time and repairs. Accordingly there is a need for an improved mixing apparatus for mixing of delicate materials, sensitive materials and abrasive materials. It is therefore desirable to have an improved mixing apparatus for mixing of delicate and other difficult to mix materials. DISCLOSURE OF INVENTION It is therefore a primary object of the present invention to provide an improved mixing apparatus for mixing of delicate, sensitive and flow resistant materials. In accordance with a primary object of the present invention, a rotary disc fluid mixing apparatus for mixing materials, comprises a support means, a mixing rotor mounted on said support means for positioning in said a fluid for mixing same, said rotor comprising a rotatable shaft, a plurality of circular discs, at least one having an aperture in a center thereof, and means for mounting said discs on an end of said shaft in axially spaced relation for enabling liquid to flow through said aperture and outward between said discs a motor drivingly connected to said shaft for rotating said rotor. BRIEF DESCRIPTION OF DRAWING The objects, advantages and features of this invention will be more readih appreciated from the following detailed description, when read in conjunction with the accompanying drawing, in which: Fig. 1 is a side elevation view in section of an exemplary first embodiment of the present invention; Fin. 2 is a view like Fig. 1 of an alternate embodiment of the present invention: g. s a p an v ew n sect on o one sc o an a ternate em o ment o t e sc pack; Fig. 4 is a plan a front elevation view in section of the disc pack of Fig. 3; and Fig. 5 is a view like Fig. 1 of a further embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION Referring to Fig. 1. an exemplary embodiment of the invention is illustrated and designated generally by the numeral 10. The apparatus, in accordance with the invention. comprises a rotary disc fluid mixer which comprises a main support housing 12 having an elongated rotary shaft 14 rotatably mounted therein in a pair of spaced bearing assemblies 16 and 18. A pair of disc packs 20 and 22 are mounted on the shaft and act as impellers for drawing fluid in and propelling it outward, thereby creating flowing of the fluid within the vessel. The shaft can have any number of disc packs along its length as will be apparent. Each disc pack comprises at least a pair of spaced apart rotary discs, one of which has a central generally unobstructed aperture therethrough for drawing fluid in and the other of which is devoid of an aperture and is connected directly to the shaft. The discs can be planar with planar relatively smooth surfaces or may have spiral vanes or ribs as will be discussed. The disc pack 20. for example, has a main disc 24 with a central hub 26 fo mounting directly on the end of shaft 14. The disc, as illustrated, is generally circular and planar disc, having planar surfaces on both sides thereof. A second disc 28 is spaced from the first disc 24 and has a central aperture 30 through which fluid flows into the space between the two discs 24 and 28. The disc 28 is connected or secured to the disc 26 by means of pins 32 and 34. These may be separate pins or formed integral with the disc pack assembly and are preferably at the innermost diameter of the disc 34. The opposing faces of the discs act on the fluid to propel it outward. A preferred way of forming a disc pack assembly, particularly for delicate and fragile solutions or mistures, is to machine the entire assembly from a casting or from a blank or billet so that the entire unit is a unitary integral unit. This eliminates cracks and joints and the problems of interference with flow of particles and the like caused by the sharp edges of bolts, screws and the like. In an alternate form of the disc pack outwardly spiraling ridges may be formed on the opposing faces of the disc to increase the propelling effect of the disc. The ridge is can be almost any height but in most cases is preferably on the order of about twice the twice the thickness of the disc. The discs normally propel the fluid by surface friction of the planar faces thereby applying a centrifugal force to the fluid forcing it outward from the space between the discs. This has an effect of propelling the fluid radially outward from between the disc creating a central void which draws fluid from the vessel into the space between the discs, and continuing to propel the fluid outward. In the Fig. 1 illustrated embodiment a second disc pack designated generally at 22 is adjustably mounted on shaft 14 in a manner so that it may be positioned at selected positions along the length of the shaft. This disc pack is similar to the disc pack 20 and comprises a disc 36 having a central hub 38 for connecting to the shaft 14. A second disc 40 includes a central aperture 42 that is larger than the shaft 14 and is connected by pins 44 and 46 to the disc 36. Any number of these disc packs may be selectively positioned in am desired array along the length of the shaft 14. The disc packs may also be formed to have multiple apertured discs with a single centrally positioned non-apertured disc. The apertured discs may be disposed on one side of the non-apertured disc or they may be on both sides thereof to draw fluid from both directions along the axis of the vessel. The rotor may a so e ma e up o a con nuous ser es o c ose y space sc un s pos one a ong the length thereof. The illustrated mixing apparatus is designed to cooperate with any form of vessel, such as an open top container or tank 48 having an opening 50 through which the shaft extends and through which material may be introduced and removed from the tank. The mixing apparatus, as illustrated, has an extension 52 of the housing which is secured, such as by bolts or the like, to a cover plate 54 for the container 48. A drive motor 56 is mounted on the housing 12 and is drivingly connected such as by V-belts or the like (not shown), but covered by protective cover 58. Any form of drive motor may be used such as. but not limited to. internal combustion engines, turbines, air and hydraulic motors. The unit may be provided with cable connecting brackets 60 and 62 for supporting the mixer apparatus from suitable support structure for lifting the mixing apparatus from and inserting it into a mixing tank. The mixer is shown co-axial with the substantially cylindrical tank but may be at any angle to the axis, including at right angles thereto. Also, the tank may have any number of different configurations, such as square, spherical or any other suitable configuration. The mixing apparatus can be used in combination with vessels and containers of any shape and size and may be positioned at any position or angle in the vessel. It may also be moved about in the vessel periodically or continuously. Referring to Fig. 2. an alternate exemplary embodiment of the invention is illustrated and designated generally by the numeral 70. The apparatus, as in the prior embodiment . comprises a rotary disc fluid mixer having a main support housing 72 having an elongated rotary shaft 74 mounted therein in a pair of spaced bearing assemblies 76 and 78. A plurality of disc packs 80, 82. 84. 86, 88, 90 and 92 are mounted on the shaft and act as impellers for drawing fluid in at their centers and propelling it radially outward, thereby creating currents or flow of the fluid throughout the volume within the vessel. Each disc pack comprises at least a pair of spaced apart rotary discs, at least one of which has a central opening serving as an inlet for drawing fluid in between the discs. The disc pack 80 may be substantially the same as that of the prior embodiment and has a main disc with a central hub for mounting directly on the end of shaft 74. The illustrated main disc is generally circular and planar, having planar surfaces on both sides thereof. A second disc is spaced from the first disc and has a central aperture functioning as an inlet through which fluid flows into the space between the two discs. A suitable drive motor is mounted on the housing 72 and is drivingly connected such as by V-belts or the like (not shown) to drive the mixing rotor, as in the prior embodiment. The discs normally propel the fluid by surface friction thereby applying a centrifugal force to the fluid forcing it outward from the space between the discs. This has an effect of propelling the fluid radially outward from between the disc creating a void which draws fluid from the vessel into the space between the discs, and continuing to propel the fluid outward. In this embodiment the remaining disc packs are adjustably mounted on shaft 74 so that they may be adjustably positioned at selected positions along the length of the shaft. These disc packs are similar to the disc pack 22 and comprises a disc 94 having a central hub 96 for drivingly connecting to the shaft 74. A second disc 98 includes a central aperture and is connected by pins to the disc 94. A pair of elongated keys 100 and 102 rest in keyways or slots in shaft 74 and engage keyways in the hub 96 in the usual manner. Any number of these disc packs may be positioned along the length of the shaft 74 and in any selected spatial relationship. The disc packs may also be formed to have multiple apertured scs w t or w t out a s ng e centra y pos t one non-aperture sc. e rotor may a so be made up of a continuous series of closely spaced disc units positioned along the length thereof. The illustrated mixing apparatus is designed to cooperate with a vessel, such as an elongated container or tank 104 having an inlet opening 106 such as axially at one end and an outlet 108 opening such as at the opposite end in a side. This effectively provides a continuous flow mixing or pumping unit. The inlet is provided with a valve 1 10 operable in the usual manner in order to selectively control the flow of fluid into the vessel. The outlet is also provided with a valve 112 operable in the usual manner in order to selectively control the flow of fluid out of the mixing apparatus. Thus, the mixing apparatus may be used in either a continuous flow mode or a batch mode. The mixer may be used with low or high viscous fluids. When the fluid is highly viscous, the discs should be closer to the diameter of the vessel so that the edges of the discs extend close to the walls of the vessel as shown in Fig. 2. This enables the rotor to push the fluid out to the walls and pull the fluid in from the walls of the vessel. In one preferred embodiment, the discs may be spaced from the wall a distance of about equal to or about twice the distance between the discs. Referring to Figs. 3 and 4, an alternate construction of a disc pack is illustrated and designated generally by the numeral 1 14. The disc pack comprises a pair of spaced apart rotary discs 1 16 and 1 18 which are cast together and finished by machining. The discs are each formed with a plurality of radially extending curved vanes or ribs which add to the frictional force of the disc faces. The disc 1 16 is formed with a shaft mounting hub 120 and with ribs 122. 124. 126, 128 and 130. The disc 1 18 has a central opening 132 for drawing fluid in between the discs and includes ribs, only three of which 134, 136 and 138 are shown The two discs 116 and 1 18 of the disc pack are connected together at the inner ends of the ribs pins at 140. 142. 144, 146 and 148 The pins, as illustrated in Fig 3. are rounded to eliminate sharp corners and to provide for a smoother flow of fluid and mixture A mixing rotor with these discs will have the ability to apply a higher force to the fluids in a mixing vessel than with planar surfaces Similarly, closely spaces pairs of discs have the ability to apply more force to fluid between the discs than farther spaced or individual discs The disc packs may also be oriented or configured so that the rotor pulls fluid in opposite axial directions along and from both ends of the rotor or the vessel towaid the center \s shown in Fig 5. a mixer 150 is formed oi a central rotoi having a cential disc pack 152 and end packs 154 and 156 mounted on an elongated shaft 158 The rotor is configured to have a central disc pack 152 having a single central mounting disc 160 with an apertuied disc 162 on one side and an apertured disk 164 on the other side The disk pack 154 on the distal or outer end of the shaft is like the end pack in pπoi embodiments The disc pack 156 is on the near or proximal end of the shaft and is like prior described disc packs but oriented in the opposite direction along the axis of the shaft 158 The two end disk packs pull fluid from the opposite ends of the rotoi oi \ essel and ioices it radialh outwaid as shown by the arrows The central disk pack draws fluid from both directions along the shaft and forces it outward as shown by the arrows While I have illustrated and described invention means of specific embodiments, it is to be understood that numerous changes and modifications may be made therein without departing from the spirit and scope of the ention. as defined in the appended claims

Claims: CLAIMS 1. A rotary disc fluid mixing apparatus for mixing fluid materials in a container, comprising: support member for association with said container; a mixing rotor mounted on said support member for positioning in said container, said rotor comprising an elongated shaft mounted for rotation on said support member and at least a first disc pack of a plurality of circular discs mounted on said shaft for rotation therewith, the disc pack consisting essentially of a first disc having a central hub for mounting said disc pack on said shaft, a second disc having an unobstructed aperture in a center thereof, and a plurality of pins connecting said second discs to said first, the pins disposed at an innermost diameter defined by said aperture, the pins connecting said first and second discs in axially spaced relation at a distance less than the radius of either disc for enabling liquid to flow through said aperture and outward between said discs, the discs having opposed planar surfaces operative to propel a fluid by surface friction outward from the space between the discs defining the sole propulsion means for fluid. 2. A rotary disc fluid mixing apparatus according to claim 1. wherein said opposed planar surfaces of said discs defining the sole propulsion means for fluid. 3. A rotary disc fluid mixing apparatus according to claim 1. wherein said opposed planar surfaces of said discs having substantially radially extending ribs having a height of no more than twice the thickness of the respective disc. 4. A rotary disc fluid mixing apparatus according to claim 1 , wherein said disc pack are of a unitary construction cast as a unit and formed by machining. 5. A rotary disc fluid mixing apparatus according to claim 4. wherein said opposed planar of said discs having radially spirling ribs having a height of no more than twice the thickness of the respective disc. 6. A rotary disc fluid mixing apparatus according to claim 1. wherein said mixing rotor comprises at least a second disc pack, the second disc pack consisting essentially of a first disc having a central hub mounting said disc pack on said shaft, a second disc having an unobstructed aperture in a center thereof, a plurality of pins connecting said second disc to one side of said first disc at an innermost diameter defined by said aperture, a third disc having an unobstructed aperture in a center thereof, a plurality of pins connecting said third disc to another side of said first disc at an innermost diameter defined by said, the pins connecting said discs in axially spaced relation at a distance less than the radius of any one of said discs for enabling liquid to flow through said aperture and outward between said discs. 7. An apparatus according to claim 1 wherein said rotor is mounted in a container and said container has an inlet and an outlet and said rotor is effective to draw fluid in via said inlet and propel said fluid out via said outlet. 8. An apparatus according to claim 7 wherein said rotor includes a plurality of said disc packs, and said disc packs are selectively positionable along said shaft. 9. A rotary disc fluid mixing apparatus for mixing fluid materials in a container, comprising: support means for association with said container; a mixing rotor mounted on said support for positioning in said container, said rotor comprising an elongated shaft mounted for rotation on said support and having a proximal end and a distal end. at least a first disc pack consisting essentially of a plurality of circular discs mounted on said shaft, the first disc pack consisting essentially of a first disc having a central hub for mounting said discs on said shaft, and a second disc having an unobstructed aperture in a center thereof, a plurality of pins connecting said first and second discs together, the pins disposed at an innermost diameter defined by said aperture, the pins connecting said first and second discs in axially spaced relation at a distance of less than the radius of the disc for enabling liquid to flow through said aperture and outward between said discs, the discs having opposed planar surfaces configured to propel a fluid by surface friction outward from the space between the discs; and a motor drivingly connected to said shaft for rotating said rotor. 10. A rotary disc fluid mixing apparatus according to claim 9. wherein said disc- pack is of a unitary construction cast as a unit and formed by machining 1 1. A rotary disc fluid mixing apparatus according to claim 9. wherein said opposed planar surfaces of said discs having radially spirling ribs having a height of no more than twice the thickness of the respective disc. 12. A rotary disc fluid mixing apparatus according to claim 9, wherein said mixing rotor comprises at least a second disc pack, the second disc pack consisting essentially of a first disc having a central hub mounting said disc pack on said shaft, a second disc having an unobstructed aperture in a center thereof, a plurality of pins connecting said second disc to one side of said first disc at an innermost diameter defined by said aperture, a third disc having an unobstructed aperture in a center thereof, a plurality of pins connecting said third disc to another side of said first disc at an innermost diameter defined by said, the pins connecting said discs in axially spaced relation at a distance less than the radius of any one of said discs for enabling liquid to flow through said aperture and outward between said discs. 13. An apparatus according to claim 12 wherein said container is a vessel which has an inlet and an outlet and said rotor is effective to draw fluid in via said inlet and propel said fluid out via said outlet. 14. An apparatus according to claim 13 wherein said rotor includes a plurality of said disc packs, and said disc packs are selectively positionable along said shaft. 15. A rotary disc fluid mixing apparatus for mixing fluid materials in a container, comprising: an elongated cylindrical vessel for containing a quantity of a fluid material to be mixed, said vessel having a fluid inlet and a fluid outlet; support member adapted for mounting on one end of said container; a mixing rotor mounted on said support for positioning in said container, said rotor comprising an elongated shaft mounted for rotation on said support and having a proximal end and a distal end. at least a first disc pack consisting essentially of a plurality of circular discs mounted on said shaft, the first disc pack consisting essentially of a first disc having a central hub for mounting said discs on said shaft, and a second disc having an unobstructed aperture in a center thereof, a plurality of pins connecting said first and second discs together, the pins disposed at an innermost diameter defined by said aperture, the pins connecting said first and second discs in axially spaced relation at a distance of less than the radius of the disc for enabling liquid to flow through said aperture and outward between said discs, the discs having opposed planar surfaces configured to propel a fluid by surface friction outward from the space between the discs; at least a second disc pack, the second disc pack consisting essentially of a first disc having a central hub mounting said disc pack on said shaft, a second disc having an unobstructed aperture in a center thereof, a plurality of pins connecting said second disc- to one side of said first disc at an innermost diameter defined by said aperture, a third disc- having an unobstructed aperture in a center thereof, a plurality of pins connecting said third disc to another side of said first disc at an innermost diameter defined by said, the pins connecting said discs in axially spaced relation at a distance less than the radius of any one of said discs for enabling liquid to flow through said aperture and outward between said discs; and a motor drivingly connected to said shaft for rotating said rotor. 16. A rotary disc fluid mixing apparatus according to claim 15. wherein said disc pack is of a unitary construction cast as a unit and formed by machining 17. A rotary disc fluid mixing apparatus according to claim 16, wherein said opposed planar surfaces of said discs having radially spirling ribs having a height of no more than twice the thickness of the respective disc. 18. An apparatus according to claim 15 wherein said container is a vessel which has an inlet and an outlet and said rotor is effective to draw fluid in via said inlet and propel said fluid out via said outlet. 19. An apparatus according to claim 18 wherein said rotor includes a plurality of said disc packs, and said disc packs are selectively positionable along said shaft. 20. An apparatus according to claim 15 wherein said rotor includes at least a third disc pack the third t disc pack consisting essentially of a first disc having a central hub for mounting said discs on said shaft, and a second disc having an unobstructed aperture in a center thereof a plurality of pins connecting said first and second discs together, the pins disposed at an innermost diameter defined by said aperture, the pins connecting said first and second discs in axially spaced relation at a distance of less than the radius of the disc for enabling liquid to flow through said aperture and outward between said discs, said first disc pack and said third disc pack oriented to pull fluid from opposite axial directions.

Inventors: GURTH MAX, GURTH, MAX
Applicants: GURTH MAX, GURTH, MAX
Application year: 2000
Main classification: B01F7
IPC codes: B01F7, B01F15