EP0036325A2 - Mélangeurs - Google Patents

Mélangeurs Download PDF

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Publication number
EP0036325A2
EP0036325A2 EP81301111A EP81301111A EP0036325A2 EP 0036325 A2 EP0036325 A2 EP 0036325A2 EP 81301111 A EP81301111 A EP 81301111A EP 81301111 A EP81301111 A EP 81301111A EP 0036325 A2 EP0036325 A2 EP 0036325A2
Authority
EP
European Patent Office
Prior art keywords
lid
motor
vessel
shaft
mixing
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP81301111A
Other languages
German (de)
English (en)
Other versions
EP0036325A3 (fr
Inventor
Gordon David Love
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
SILVERSON MACHINES Ltd
Original Assignee
SILVERSON MACHINES Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by SILVERSON MACHINES Ltd filed Critical SILVERSON MACHINES Ltd
Publication of EP0036325A2 publication Critical patent/EP0036325A2/fr
Publication of EP0036325A3 publication Critical patent/EP0036325A3/fr
Withdrawn legal-status Critical Current

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
    • B01F35/60—Safety arrangements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F27/00—Mixers with rotary stirring devices in fixed receptacles; Kneaders
    • B01F27/80—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis
    • B01F27/90—Mixers with rotary stirring devices in fixed receptacles; Kneaders with stirrers rotating about a substantially vertical axis with paddles or arms 
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
    • B01F35/30—Driving arrangements; Transmissions; Couplings; Brakes
    • B01F35/32—Driving arrangements
    • B01F35/321—Disposition of the drive
    • B01F35/3214—Disposition of the drive at the upper side of the axis, e.g. driving the stirrer from the top of a receptacle
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01F—MIXING, e.g. DISSOLVING, EMULSIFYING OR DISPERSING
    • B01F35/00—Accessories for mixers; Auxiliary operations or auxiliary devices; Parts or details of general application
    • B01F35/40—Mounting or supporting mixing devices or receptacles; Clamping or holding arrangements therefor
    • B01F35/41—Mounting or supporting stirrer shafts or stirrer units on receptacles
    • B01F35/411—Mounting or supporting stirrer shafts or stirrer units on receptacles by supporting only one extremity of the shaft
    • B01F35/4111—Mounting or supporting stirrer shafts or stirrer units on receptacles by supporting only one extremity of the shaft at the top of the receptacle

Definitions

  • This invention relates to mixer devices suitable for use with materials which, when subject to mixing or disintegration, give off noxious gases or infectious bacteria.
  • Devices currently available for mixing such materials include a mixer head comprising rotor and stator elements which is supported below a lid for a mixing vessel.
  • a rotor shaft extends upwardly from the head via an aperture in the lid and seals are provided between the shaft and the lid and between the lid and the vessel.
  • an operator must lift the vessel and the lid to bring locating means on the lid into engagement with locating means on the housing of a motor, thereby to secure the vessel to the housing, and to couple the rotor shaft to a downwardly extending motor shaft.
  • the seal between the rotor shaft is operative to prevent the escape of gases or bacteria both before and after the rotor shaft has been coupled to the motor shaft.
  • a mixer device suitable for mixing or disintegrating materials which, when subjected to mixing or disintegration, give off noxious gases or infectious bacteria
  • the device comprising a mixing head comprising a rotor element mounted on a rotor shaft and a cooperating stator element, means supporting the stator element below a lid for an open-topped mixing vessel, the rotor shaft extending upwardly from the mixing head and through an aperture in the lid, sealing means being provided between the rotor shaft and the lid, and the lid being adapted at or near the periphery thereof for sealing engagement with a side wall of the vessel, a drive motor, a support for the drive motor, a guide along which the motor support is movable in a direction having a vertical component, means for releasably coupling an output shaft of the motor to the rotor shaft, and operating means for moving the motor support along the guide, whereby, in use, the device is arranged with the lid resting on the side wall of the vessel, the mixing head within the vessel,
  • the device shown in Figures 1 and 2 of the drawings is suitable for use in a medical laboratory where materials such as human tissues, organs or excreta have to be mixed or disintegrated. Such materials are usually stored in a refrigerated condition and may give off noxious gases or bacteria when brought up to room temperature and subjected to mixing or disintegration. Mixing is conveniently effected in a cylindrical, open-topped mixing vessel of plastics or the like flexible material.
  • a suitable vessel 1 for use with the present device has a circular base 3 and a generally cylindrical side wall 5.
  • a short distance below the rim of the vessel 1 is a flange 7 having a radially outer section which is downturned. The flange 7 is used in securing the vessel 1 to the mixer device, as hereinafter described.
  • the present mixer device includes a lid 9 for closing the vessel 1 and carries a support 11 for a mixer head 13. Means 15 are provided for locating the lid 9 and the head 13 relative to a housing 17 for a drive motor (not shown).
  • a lower part 19 of the lid is tapered, an external flange 21 is formed on an upper part of the lid, and an 0-ring 23 of elastomeric material is fitted into a circumferential groove of part-circular section between the part 19 and the flange 21.
  • the tapered part 19 of the lid 9 is fitted into the top of the vessel 1 and the 0-ring 23 engages an upper edge of the side wall 5.
  • a clamping ring 20 has an upturned, radially inner section which is fitted beneath the flange 7 on the vessel 1.
  • the lid 9 is clamped to the vessel 1 by means of a series of bolts 24, each of which extends upwardly through aligned apertures in the clamping ring 20 and the lid 9 and has a nut 22 threadably engaged with its upper end. By tightening the nuts 22 the lid 9 is drawn downwardly so that the 0- ring 23 is compressed and forms a fluid-tight seal between the lid and the vessel 1.
  • the mixer head 13 includes a rotor element 23 and a cooperating stator element 25.
  • the rotor element 23 is formed of a plurality of blades outstanding from a circular rotor plate and is secured to a lower end of a rotor shaft 31.
  • the stator element 25 is formed of an apertured cylindrical side wall having a flange at its upper end.
  • the flange on the stator element 25 is screwed to the undersurface of an annular stator plate 37, which forms part of the above- mentioned support 11.
  • Four pillars 39 support the stator plate 37 below an annular plate 41 at an upper end of the support 11.
  • baffle plates 27 Secured to the stator element 25 are a pair of upstanding baffle plates 27.
  • the plates 27 are disposed at diametrically opposed locations on the element 25.
  • Each is formed of a lower section 33 which is vertical and an upper section 35 which is inclined to the vertical at an angle between 10 and 45 0 , preferably 30 0 .
  • both upper and lower sections are vertical.
  • the locating means 15 include a hollow cylindrical member 43 which has its bottom wall 45 fitted into a central aperture in the lid 9 and an apertured boss on the wall 45 fitted into the central aperture in the plate 41.
  • a locating pin 47 is provided near to an upper end of the member 43 and the member has a bevelled upper edge.
  • the rotor element 23 is disposed inside the stator element 25.
  • Shaft 31 extends upwardly from the rotor element, first via a bush 51, which is fitted into a central aperture in the stator plate 37 and serves as a bearing for the shaft, and then via the apertured boss on the wall 45 to the interior of the member 43.
  • An upper end of the shaft 31 is tapered, and just below the taper is a drive pin 53.
  • a seal 55 for preventing the escape of noxious gases or bacteria from the interior of the vessel 1 is provided within the cylindrical member 43 of the locating means 15.
  • the seal 55 is a seal of the kind disclosed in British specification No. 1,084,803.
  • the seal 55 includes a stationary seal seat, which is fitted into the central aperture in the bottom wall 45 of the member 43, and a seal member, which is rotatable with the shaft 31 and which is urged downwardly into engagement with the stationary seal seat by a helical spring.
  • An 0-ring is provided between the rotatable member and the shaft 31.
  • An upper end of the spring 61 engages a seal drive collar 63 on the shaft 31.
  • An inlet pipe 64 and an outlet pipe 66 communicate with the interior of the vessel 1 via respective inlet and outlet apertures in the lid 9.
  • the pipes 64 and 66 which are used for flushing the interior of the vessel 1 after mixing, are normally closed by rubber bungs.
  • a support 67 for the drive motor includes the housing 17 and a vertical column 65 which has the housing 17 mounted on an upper end thereof.
  • the column 65 is slidable within a tubular member 69 whose lower end is fitted into an aperture in a top wall of a housing 71. Movement of the column 65 relative to the member 69 is confined to movement in a vertical direction by a screw 74 which is threadably engaged in the top wall of the housing 71 and has one end thereof projecting into a vertical groove 76 in the column.
  • Sleeve bearings 73, spaced apart by a bush spacer 75, are provided within the tubular member 69.
  • a cylindrical shroud 77 extends downwardly from the housing 17, coaxially of and outside the member 69.
  • operating means which include a cam 79 mounted on a horizontal spindle 81.
  • the spindle 81 is supported by a bearing 83 in a rear wall of the housing 71 and a bearing 85 in a front wall of the housing.
  • a forward end of the spindle 81 extends through an aperture in the front wall of the housing and has a handle 87 secured thereto.
  • the column 65 normally rests with its lower end on the cam 79 in the housing 71.
  • An output shaft 89 of the motor extends vertically downwardly from the housing 17.
  • a sleeve 91 Secured to a lower end of the shaft 89 is a sleeve 91 for coupling the shaft to the rotor shaft 31.
  • the sleeve 91 is formed with two slots 93 for receiving respective opposite ends of the pin 53 on the shaft 31.
  • Each slot 93 has one axially extending edge and one edge which is inclined to the axis of the sleeve 91.
  • a hollow cylindrical member 95 is secured to the housing 17, coaxially of the shaft 89, and serves as a locating means which cooperates with the locating means 15 on the lid 9.
  • a lower section of the member 95 is formed with an increased internal diameter so that a shoulder 99 is formed between this lower section and an upper section of the member.
  • a bevel is formed at a lower edge of the lower section of the member 95 and an axially extending slot 105 is provided for receiving the pin 47 on the locating means 15.
  • the housing 71 is secured to a horizontally extending framework 107 and a plate 109 for supporting the vessel 1 has studs 111 which are fitted into apertures 113 in the framework.
  • the apertures 113 are disposed at a predetermined distance from the housing 71 so that the rotor shaft 31 is approximately coaxial with the shaft 89 of the motor when the vessel is located centrally of the plate 109.
  • the handle 87 Prior to using the present device the handle 87 has been rotated to bring the housing 17 to a raised, inoperative position and the lid 9 is placed on top of the vessel 1 with the mixer head 13 inside the vessel. An operator can then place the vessel 1 together with the lid 9 on the plate 109 with the member 43 of the locating means 15 axially aligned, or nearly axially aligned, with the member 95. The lid 9 is clamped on to the vessel 1 in the manner described above. Since the shaft 31 is disengaged from the sleeve 91, the spring which is engaged between the seal member in the seal 55 and the drive collar 63, urges the shaft 31 upwardly to a position wherein the plate in the rotor 23 engages the stator plate 37.
  • the motor in the housing 17 is now switched on so that the rotor element 23 is rotated.
  • material within the stator element 25 is expelled radially outwardly via the apertures in the side wall and fresh material is drawn upwardly into the stator element.
  • the material is subjected to large shearing forces, which effect thorough mixing or disintegration, as the material passes first between the rotating blades 27 and the wall 25 and then through the apertures in the wall.
  • baffle plates 27 In the absence of the baffle plates 27, material expelled from the stator element has a high velocity in the circumferential direction as well as in a radially outwards direction. This circumferential movement may be sufficient to produce a vortex of sufficient magnitude for the mixer head 13 to be completely emptied of material. The baffle plates 27 reduce this circumferential flow sufficiently to prevent such a vortex action.
  • the handle 87 is rotated so that the cam 79 reengages the lower end of the column 65 and then moves the column upwardly so that the locating means 15 and 95 are disengaged.
  • the spring in the seal 55 expands slightly and forces the rotor shaft upwardly until the rotor plate engages the stator plate 37. However, the spring is still sufficiently compressed to maintain the seal member in engagement with the seal seat, thereby maintaining a gas-tight seal between the rotor shaft 31 and the support 11 and the lid 9.
  • the vessel 1 and lid 9 can then be removed from the housing 17 and framework 107 and placed in a fume cupboard, prior to releasing the bolts 24 and removing the lid from the vessel.
  • the vessel 1 and the lid 9 are removed from the housing 17 and the framework 107 and placed in a fume cupboard.
  • the rubber bung is removed from the pipe 64 and a sample of the mixed material is withdrawn from the vessel 1 by means of a pipette.
  • both bungs are removed, and the liquid is removed from the vessel by pouring through the outlet pipe 64.
  • the interior of the vessel 1 is then cleansed, by connecting a source of water to the inlet pipe 64 and thereby forcing any liquid or solid material remaining inside the vessel 1 or on the undersurface of the lid 9 outwardly via the outlet pipe 66.
  • a second device is a modification of the device shown in Figures 1 and 2 and is designed for use with mixing vessels which are made of plastics or the like flexible material but which are more accurately manufactured, in particular with vessels whose internal diameter at the top thereof is equal or substantially equal to a predetermined value.
  • a lower part 19 of a lid 9 is tapered and there is a flange 21 above the part 19.
  • a circular groove 26 is formed on the upper surface of the lid 9.
  • the lid 9 is arranged with the lower tapered part 19 extending into the top of a vessel 1, the diameter of the part being such that the lid rests with the top edge of the vessel engaging the part 19 at a location between the top and bottom of the part and with the flange 21 vertically spaced above the top edge.
  • the operating means are then actuated, as described above, so that the member 95 moves down to engage the member 43, the motor shaft 89 engages the rotor shaft 31, and the rotor plate is disengaged from the stator plate 37. Downwards movement continues until the shoulder 99 on the member 95 has engaged the top of the member 43 and the cam 79 has been disengaged from the column 65.
  • the combined weight of the housing 17 and the motor within the housing, the column 65, the locating means 15 and member 95, the lid 9 and the mixer head 13 forces the tapered part 19 of the lid into the top of the vessel 1, and this downwards movement of the part 19 causes a radially outwards movement of the flexible material of the vessel 1.
  • the upper edge of the vessel 1 is therefore maintained in a fully stretched or slightly expanded condition and a fluid tight seal is formed between the vessel 1 and the lid 9.
  • a plurality of spring clips (not shown) are then employed to maintain the lid 9 in engagement with the vessel 1, each clip having one limb engaged below the flange 7 on the vessel and another limb engaged in the circular groove 22 on the lid.
  • the device described above may have a microswitch connected in series with the drive motor.
  • the microswitch is arranged to be open when the output shaft 89 of the motor is decoupled from the rotor shaft 31 and closed when the two shafts are coupled together. This prevents rotation of the rotor shaft 31 whilst the plate in the rotor 23 is engaged with the stator plate 37. It also prevents damage to the pin 53 and the sleeve 91 due to engagement of the rotating shaft 89 with the stationary rotor shaft 31.
  • the microswitch can be arranged to be operated by a further cam on the spindle 81.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Accessories For Mixers (AREA)
  • Crushing And Pulverization Processes (AREA)
  • Mixers Of The Rotary Stirring Type (AREA)
EP81301111A 1980-03-17 1981-03-17 Mélangeurs Withdrawn EP0036325A3 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB8008927 1980-03-17
GB8008927 1980-03-17

Publications (2)

Publication Number Publication Date
EP0036325A2 true EP0036325A2 (fr) 1981-09-23
EP0036325A3 EP0036325A3 (fr) 1982-09-22

Family

ID=10512146

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81301111A Withdrawn EP0036325A3 (fr) 1980-03-17 1981-03-17 Mélangeurs

Country Status (1)

Country Link
EP (1) EP0036325A3 (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0111148A2 (fr) * 1982-11-26 1984-06-20 Dipl.-Ing. H. List Industrielle Verfahrenstechnik Appareil pour agiter pourvu d'une coudre protectrice sensible aux coups
WO2007003318A2 (fr) * 2005-07-04 2007-01-11 Frank Vitzthum Dispositif et procede pour l'homogeneisation par rotor/stator
DE102010041242A1 (de) 2010-09-23 2012-03-29 Evonik Rohmax Additives Gmbh Verfahren zur Herstellung von Polymerdispersionen
CN112844207A (zh) * 2021-02-24 2021-05-28 戚聿斌 搅拌罐夹紧装置、搅拌装置及其使用方法

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE576528C (de) * 1930-10-30 1933-05-12 Paul Lenart Mischvorrichtung
US2157683A (en) * 1936-12-24 1939-05-09 Voilrath Paul Device for mixing, sifting, and kneading
US3223492A (en) * 1960-11-14 1965-12-14 Robert C Geitz Pressure vessel
GB1084803A (en) * 1963-03-21 1967-09-27 Silverson Machines Ltd Improvements in mixer devices
DE1809018A1 (de) * 1968-11-15 1970-12-03 Dieter Kupka Ruehrwerk
DE1948998A1 (de) * 1969-09-27 1971-04-22 Bayer Ag Mischkopf zum Vermischen schnell miteinander reagierender chemischer Komponenten
GB1446423A (en) * 1972-06-22 1976-08-18 Tweedy Of Burnley Ltd Mixing and/or comminuting apparatus
FR2321079A1 (fr) * 1975-08-12 1977-03-11 Braren Cyclo Getriebe Dispositif pour echanger le joint d'etancheite d'un systeme d'entrainement pour melangeurs, muni d'un joint d'etancheite

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE576528C (de) * 1930-10-30 1933-05-12 Paul Lenart Mischvorrichtung
US2157683A (en) * 1936-12-24 1939-05-09 Voilrath Paul Device for mixing, sifting, and kneading
US3223492A (en) * 1960-11-14 1965-12-14 Robert C Geitz Pressure vessel
GB1084803A (en) * 1963-03-21 1967-09-27 Silverson Machines Ltd Improvements in mixer devices
DE1809018A1 (de) * 1968-11-15 1970-12-03 Dieter Kupka Ruehrwerk
DE1948998A1 (de) * 1969-09-27 1971-04-22 Bayer Ag Mischkopf zum Vermischen schnell miteinander reagierender chemischer Komponenten
GB1446423A (en) * 1972-06-22 1976-08-18 Tweedy Of Burnley Ltd Mixing and/or comminuting apparatus
FR2321079A1 (fr) * 1975-08-12 1977-03-11 Braren Cyclo Getriebe Dispositif pour echanger le joint d'etancheite d'un systeme d'entrainement pour melangeurs, muni d'un joint d'etancheite

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0111148A2 (fr) * 1982-11-26 1984-06-20 Dipl.-Ing. H. List Industrielle Verfahrenstechnik Appareil pour agiter pourvu d'une coudre protectrice sensible aux coups
EP0111148A3 (fr) * 1982-11-26 1986-07-16 Dipl.-Ing. H. List Industrielle Verfahrenstechnik Appareil pour agiter pourvu d'une coudre protectrice sensible aux coups
WO2007003318A2 (fr) * 2005-07-04 2007-01-11 Frank Vitzthum Dispositif et procede pour l'homogeneisation par rotor/stator
WO2007003318A3 (fr) * 2005-07-04 2007-04-26 Frank Vitzthum Dispositif et procede pour l'homogeneisation par rotor/stator
DE102010041242A1 (de) 2010-09-23 2012-03-29 Evonik Rohmax Additives Gmbh Verfahren zur Herstellung von Polymerdispersionen
WO2012038116A1 (fr) 2010-09-23 2012-03-29 Evonik Rohmax Additives Gmbh Procédé de fabrication de dispersions de polymère
CN112844207A (zh) * 2021-02-24 2021-05-28 戚聿斌 搅拌罐夹紧装置、搅拌装置及其使用方法

Also Published As

Publication number Publication date
EP0036325A3 (fr) 1982-09-22

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Inventor name: LOVE, GORDON DAVID