EP0003225B1 - Tambour de grenaillage - Google Patents

Tambour de grenaillage Download PDF

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Publication number
EP0003225B1
EP0003225B1 EP19780101672 EP78101672A EP0003225B1 EP 0003225 B1 EP0003225 B1 EP 0003225B1 EP 19780101672 EP19780101672 EP 19780101672 EP 78101672 A EP78101672 A EP 78101672A EP 0003225 B1 EP0003225 B1 EP 0003225B1
Authority
EP
European Patent Office
Prior art keywords
drum
machine according
blasting
diameter
passage
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.)
Expired
Application number
EP19780101672
Other languages
German (de)
English (en)
Other versions
EP0003225A1 (fr
Inventor
Emil Berna
Sergej Dipl.-Ing. Toedtli
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.)
Georg Fischer AG
Original Assignee
Georg Fischer AG
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 Georg Fischer AG filed Critical Georg Fischer AG
Publication of EP0003225A1 publication Critical patent/EP0003225A1/fr
Application granted granted Critical
Publication of EP0003225B1 publication Critical patent/EP0003225B1/fr
Expired legal-status Critical Current

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24CABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
    • B24C3/00Abrasive blasting machines or devices; Plants
    • B24C3/18Abrasive blasting machines or devices; Plants essentially provided with means for moving workpieces into different working positions
    • B24C3/26Abrasive blasting machines or devices; Plants essentially provided with means for moving workpieces into different working positions the work being supported by barrel cages, i.e. tumblers; Gimbal mountings therefor
    • B24C3/266Abrasive blasting machines or devices; Plants essentially provided with means for moving workpieces into different working positions the work being supported by barrel cages, i.e. tumblers; Gimbal mountings therefor for continuously travelling workpieces
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22DCASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D31/00Cutting-off surplus material, e.g. gates; Cleaning and working on castings
    • B22D31/002Cleaning, working on castings
    • B22D31/007Tumbling mills

Definitions

  • the invention relates to a continuous drum blasting machine for a continuous passage of the workpieces to be treated with centrifugal jets with at least one drum rotating about an axis inclined in the direction of passage.
  • a continuous drum blasting machine in which a cylindrical drum rotates about an axis inclined in the direction of passage and in the interior of which a plurality of longitudinally offset jet nozzles are arranged for cleaning and deburring workpieces, in particular castings. Since the workpieces are partly carried along by the rotating drum inner wall and then fall back into the lower drum area, but partly run down along the inclined surface, one is created. completely uncontrollable and uneven flow and turning movement of the workpieces. This leads to a strongly fluctuating throughput with workpieces that are blasted in very different ways, particularly in the case of continuously different workpieces. For the arrangement of powerful centrifugal wheels, the drum diameter must be chosen very large, which adversely affects the manufacturing costs and size as well as the circulation behavior of such machines.
  • US-A 2020447 also shows a continuous drum blasting machine whose axis is arranged horizontally, the drum being either conically enlarging or conically reducing from the outlet and the inlet opening to the middle of the drum, and blasting nozzles or centrifugal wheels are arranged on each drum end. Because the lower surface line of the drum rises and falls once, no uniform throughput and turning movement of the workpieces is guaranteed either.
  • FR-A 22 01 150 has disclosed a device for cooling castings and for cooling and drying molding sand, which has a drum which tapers conically in the direction of passage. The inclination of the drum axis can be adjusted to achieve the longest possible dwell times for castings and sand. This device is not suitable for blasting treatment of workpieces, which is why even passage and turning of the workpieces is neither necessary nor provided.
  • the object of the present invention is to create a continuous drum blasting machine of the type mentioned at the outset which is simplified, by means of which a uniform, approximately determinable workpiece throughput is achieved with a simultaneous blasting effect on all workpieces and in which a maintenance-friendly arrangement of powerful centrifugal wheels is ensured.
  • the configuration and arrangement of the drum according to the invention results in a driving movement perpendicular to the drum axis and subsequently a falling movement of the workpiece, which largely prevents uncontrolled slipping of the workpieces, which leads to a uniform workpiece feed.
  • the advantage of this is that the dwell time of the workpieces in the blasting space can be determined and reproduced, as a result of which overexposure or underexposure of workpieces is reduced in comparison with conventional machines.
  • the automatic feed enables the drum to empty itself.
  • the arrangement according to the invention of the centrifugal wheel in front of the inlet opening on the side of the largest drum diameter enables a simple and maintenance-friendly construction, even if several drums are arranged one behind the other, whereby the detection of the entire jacket length of the drum by the blasting fan means a constant change of the impact angle of the blasting medium onto the Workpiece surface causes what increases the cleaning performance.
  • the advantageous arrangement of the drum for the workpieces and the take-off drum concentrically inside a drivable housing drum enables the drum drive to be arranged in a maintenance-friendly manner. This significantly reduces the manufacturing costs of such a blasting machine by saving transport screws for the mixture and the otherwise additional drive for the take-off drum.
  • the continuous drum blasting machine shown in Fig. 1 consists essentially of a blasting chamber 1 with drums 2, 2a arranged therein and centrifugal wheels 3, 3a arranged thereon, an input device 4, a discharge device 5, a collection and return transport device 6 for the blasting medium and the Sand as well as one of the abrasive preparation plants (not shown) and feed to the centrifugal wheels 3,
  • the two drums 2 and 2a are arranged one behind the other in the direction of passage 7 of the workpieces to be blasted and with axes 8 and 8a inclined in the direction of passage 7.
  • the diameter of the two drums 2, 2a gradually decreases in the direction of passage 7, as a result of which the drum 2, 2a is formed from a plurality of cylindrical circumferential parts 9 with different diameters from one another and annular surfaces 10 running perpendicularly thereto.
  • the diameter of the drum 2, 2a decreases continuously in the direction of passage 7, as a result of which the drum is frustoconical.
  • the inclination of the axes 8, 8a is preferably chosen so that the lowest point of the largest diameter of the drums 2, 2a is the same height or slightly lower than the lowest point of the smallest diameter.
  • Driving webs 11 running in the direction of passage 7 are arranged on the inner circumference of the drum, these being attached to the individual circumferential parts 9 offset from one another in the axial direction.
  • the drums 2, 2a are mounted on rollers 12, some of which can be driven by means of a drive, not shown, whereby the drums 2, 2a are made to rotate.
  • each of the drums 2, 2a can be driven in an individually controllable manner, in which case different speeds and / or different directions of rotation can also be selected.
  • the axes 8, 8a of the two drums 2, 2a are arranged with the same inclination but laterally offset from one another.
  • the centrifugal wheels 3, 3a are each attached to the blasting chamber 1 in front of or directly in the region of an inlet opening 13 on the side of the largest diameter of the drums 2, 2a, wherein they are arranged such that their blasting fans 14 cover the entire jacket length 15 of the drums 2, 2a recorded. This arrangement is considerably facilitated, in particular in the case of the second drum 2a, by its lateral offset, the accessibility of the centrifugal wheels 3, 3a also being ensured for the purpose of replacing wearing parts.
  • the input device 4 In front of the inlet opening 13 of the first drum 2, the input device 4 is arranged, which consists of an input chamber 16 attached to the blasting chamber 1 and a feed device 17 - e.g. a vibrating trough or a conveyor belt.
  • the bottom of the input chamber 16 is designed as a slide 18, and elastic curtains 19, e.g. attached from rubber.
  • the discharge device 5 consists of a horizontally arranged cylindrical take-off drum 20, a funnel 21 arranged fixedly between the take-off drum 20 and the outlet opening 50 of the second drum 2a, and a conveyor belt 22 connected to the take-off drum 20.
  • the take-off drum 20 can be driven in a chamber 23 on rollers 24 mounted and has an inside up to the center screw conveyor 25, through which a rabyrinth-like seal of the blasting chamber 1 is simultaneously created.
  • the drums 2, 2a and the take-off drum 20 are preferably permeable on their circumference through the use of perforated plates for the mixture of blasting agent, sand and blasted particles, this mixture falling into a collecting chamber 26 of the collecting and return transport device 6 arranged underneath.
  • the mixture is fed by means of two screw conveyors 27 to an elevator 28, which transports it to the blasting agent processing system, which is not shown.
  • the operation of the continuous drum blasting machine described here is as follows.
  • the workpieces to be blasted are fed continuously by means of the feed device 17 via the chute 18 through the inlet opening 13 to the first drum 2, where the first blasting treatment takes place by means of the centrifugal wheel 3.
  • the workpieces with the peripheral parts 9 are taken perpendicular to the inclined axis 8 due to the static friction or with the driving webs 11 according to the arrows 29.
  • the workpieces fall and turn vertically downwards in accordance with the arrows 29, whereby they at the same time get into the next circumferential section 9.
  • the workpieces pass through the drum 2 from stage to stage, which results in an automatic feed movement with simultaneous circulation of the workpieces.
  • the step-like design of the drum thus prevents the workpieces from uncontrollably moving through.
  • the inclined axis and the conical drum cause the same movement of the workpieces and forwards, whereby the horizontal or slightly rising lower surface line of the drum prevents uncontrolled forward movement due to slipping.
  • the workpieces are again irradiated by means of the second centrifugal wheel 3a.
  • the workpiece transfer takes place directly from the first to the second drum, since the conical design ensures that the drums interlock.
  • the workpieces are then fed through the fixed hopper 21 to the take-off drum 20, where the workpieces are drummed out in a known manner.
  • the take-off drum 20 transfers the cleaned workpieces to the conveyor belt 22, by means of which they are fed to the next use.
  • the use of only one drum is also possible with a lower workpiece throughput.
  • the number of drums must be determined depending on the blasting and throughput time, and more than two drums can also be used.
  • the housing drum 30 consists of a cylindrical part 31 and a part 32, seen in the direction of flow 7, adjoining it.
  • the higher end of the frustoconical part 32, seen in the direction of flow 7, opposite the end of the cylindrical part 31 results in the region of the joint of these two parts 31, 32 a collecting basin 33 for the mixture of blasting agent, sand and blasted particles, the casing of the housing drum 30 in the peripheral region of the collecting basin 33 having openings 34 for the passage of the mixture.
  • the cylindrical part 31 has two bearing rings 35, by means of which the housing drum is mounted on rollers 36, some of which can be driven by means of a drive, not shown, whereby the housing drum 30 is caused to rotate.
  • rollers 36 are fastened to a frame 37 which is arranged on a foundation 38 which has an inclined surface.
  • a drum 2 for the workpieces to be blasted and a take-off drum 20 are arranged concentrically therewith, all three drums rotating together in the same direction around the inclined axis 8 due to their mutual fixed connection.
  • the diameter of the drum 2 is gradually reduced in the direction of passage 7, said cylindrical peripheral parts 9 having carrier webs 11 fastened to the inner wall and ring surfaces 10 running perpendicularly thereto.
  • the preferably cylindrical extraction drum 20 Directly adjoining the blasting drum 2 is the preferably cylindrical extraction drum 20, which has a screw conveyor 25 in the interior which extends to the center and at the same time creates a labyrinth-like seal on the outlet side of the drum 2.
  • the take-off drum 20 is provided with sector-shaped metal sheets 44, which are fastened to the inner wall of the drum in the direction of passage 7 and circumferentially offset from one another.
  • the size and arrangement of the sector-shaped sheets 44 are selected such that a labyrinth-like seal is also formed on the outlet side of the drum 2.
  • the sheets 44 have a sector angle 45 of 120 °.
  • the drum 2 and the take-off drum 20 are preferably permeable on their circumference through the use of perforated plates for the mixture of blasting agent, sand and blasted particles, this slipping inside the housing drum 30 to the collecting basin 33.
  • a holding device 39 fixedly connected to the frame 37 two centrifugal wheels 3 with their drive motors 42 and an input chamber 16 are fastened.
  • the bottom of the input chamber 16 is designed as a slide 18 and elastic curtains 19, e.g. made of rubber, fastened.
  • a feed device 17-e.g. a vibrating trough-arranged on the foundation 38 In front of the input chamber 16 is a feed device 17-e.g. a vibrating trough-arranged on the foundation 38.
  • the two centrifugal wheels 3 are arranged in the area of an inlet opening 13 of the blasting drum 2 in such a way that their blasting fans 14 collectively cover the entire inner jacket length 15 of the blasting drum 2.
  • a slide 43 On the output side of the housing drum 30 is a slide 43, which is the blasted Feeds workpieces to a conveyor belt or a vibrating trough 22. If two continuous drum blasting machines are set up in parallel next to one another, a chute or a conveyor belt 22 can be loaded with two chutes 43.
  • the centrifugal jet machine according to the invention is suitable for all drum-capable workpieces and can be advantageous following an automatic molding and casting process. system can be used. Since tests have shown that the uniform conveying effect of such a blasting machine is largely independent of the degree of filling of the drum, its throughput can easily be adapted to the respective throughput of an automatic molding and casting system, as a result of which intermediate storage can be avoided.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Centrifugal Separators (AREA)

Claims (15)

1. Machine a grenailler à tambour, à fonctionnement continu, destinée à traiter par projection centrifuge de grenaille des pieces en circulation continue, avec au moins un tambour tournant (2, 2a) dont l'axe (8, 8a) est incliné par rapport à la direction (7) de circulation, machine caractérisée en ce que le diamètre du tambour (2, 2a) diminue dans la direction de circulation, au moins une turbine de projection (3, 3a) étant disposée sur le côté de plus grand diamétre du tambour (2, 2a), le diamètre du tambour (2, 2a) diminuant par gradins, ou diminuant de façon continue et l'axe (8, 8a) étant incliné de manière que le point le plus bas de la partie de plus grand diamètre se trouve à la même hauteur ou plus bas que le point le plus bas de la partie de plus petit diamètre du tambour (2, 2a).
2. Machine selon la revendication 1, caractérisé en ce que le tambour (2, 2a) à gradins comporte plusieurs parties périphériques cylindriques (9) de diamètre différents, reliés par des surfaces annulaires (10) qui leurs sont perpendiculaires.
3. Machine selon la revendication 1, caractérisé en ce que la surface latérale. intérale intérieure du tambour comporte des nervures d'entraînement (11) dans la direction (7) de circulation.
4. Machine selon la revendication 1, caractérisée en ce que la ou les turbines de projection (3, 3a) sont disposées de manière que leur jet (14) en éventail couvre toute la longueur de la surface intérieure (15) du tambour (2, 2a).
5. Machine selon l'une quelconque des revendications 1 à 4, caractérisée en ce qu'elle comporte au moins deux tambours (2, 2a) disposés l'un derrière l'autre dans la direction (7) de circulation, et dont les axes (8, 8a) sont également inclinés et sont décalés latéralement.
6. Machine selon la revendication 5, caractérisé en ce que les turbines de projection (3, 3a) sont décalées lateralément vers le haut par rapport aux axes (8, 8a) des tambours (2, 2a).
7. Machine selon l'une quelconque des revendications 1 à 4, caractérisée en ce qu'elle comporte un tambour d'évacuation (20) de préférence cylindrique, disposé coaxialement à la partie de plus petit diamètre du tambour (2) au quel il est fixé, les deux tambours (2, 20) étant disposés dans une enceinte (30) en forme de tambour.
8. Machine selon la revendication 7, caractérisée en ce que l'enceinte (30) en forme de tambour est disposée concentriquement avec ledit tambour (2) et peut être entraînée avec lui.
9. Machine selon la revendication 8, caractérisée en ce que l'enceinte (30) en forme de tambour est constituée par une partie cylindrique (31) et une partie (32) en forme de tronc de cône dont le diamétre diminue dans la direction (7) de circulation.
10. Machine selon la revendication 9, caractérisée en ce que des ouvertures (34) sont disposées dans une région périphérique la plus basse de l'enceinte (30) en forme de tambour.
11. Machine selon la revendication 10, caractérisée en ce qu'un dispositif de retour (6) est disposé au-dessous des ouvertures (34) de l'enceinte (30) en forme de tambour relié à un dispositif (41) de conditionnement d'abrasif.
12. Machine selon l'une quelconque des revendications 7 à 11, caractérisée en ce qu'elle comporte au moins une ou de préférence, deux turbines de projection (3, 3a) montées sur un dispositif de fixation (39) disposé devant l'enceinte (30) en forme de tambour.
13. Machine selon l'une quelconque des revendications 7 à 12, caractérisée en ce que les surfaces enveloppantes du tambour (2) et du tambour d'evacuation (20) sont faites en tôles perforées.
14. Machine selon l'une quelconque des revendications 7 à 13, caractérisée en ce que le tambour d'évacuation (20) comporte, dans la direction (7) de circulation, des tôles en forme de secteurs décalées les unes par rapport aux autres suivant la circonférence.
15. Machine selon l'une quelconque des revendications 7 à 13, caractérisée en ce que le tambour d'évacuation (20) comporte un hélice transporteuse (25) qui s'étend jusqu'à l'axe central (8).
EP19780101672 1978-01-31 1978-12-14 Tambour de grenaillage Expired EP0003225B1 (fr)

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
CH102378 1978-01-31
CH1023/78 1978-01-31
CH1391/78 1978-02-08
CH139178 1978-02-08
CH10094/78 1978-09-27
CH1009478 1978-09-27

Publications (2)

Publication Number Publication Date
EP0003225A1 EP0003225A1 (fr) 1979-08-08
EP0003225B1 true EP0003225B1 (fr) 1981-05-20

Family

ID=27172611

Family Applications (1)

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EP19780101672 Expired EP0003225B1 (fr) 1978-01-31 1978-12-14 Tambour de grenaillage

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EP (1) EP0003225B1 (fr)
DE (1) DE2860732D1 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105171621A (zh) * 2015-10-12 2015-12-23 嘉善县汾湖铸钢厂 一种滚筒式抛丸机
CN116141210B (zh) * 2023-04-17 2023-06-30 江苏兴海特钢有限公司 一种合金钢钣金件喷砂处理设备

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1661934A (en) * 1923-03-26 1928-03-06 New Haven Sand Blast Company Sand-blast machine
US2020447A (en) * 1934-03-14 1935-11-12 St Georges Engineers Ltd Sand blast apparatus
FR1361160A (fr) * 1963-06-26 1964-05-15 Fischer Ag Georg Machine de grenaillage par turbine
US3690068A (en) * 1970-09-08 1972-09-12 Carborundum Co Continuous treating apparatus
NL156945B (nl) * 1972-09-29 1978-06-15 Expert Nv Inrichting voor het koelen en drogen van vormzand en voor het koelen van gietstukken.
CH560081A5 (en) * 1973-08-13 1975-03-27 Expert Nv Heat resistant bond foundry sand recovery - by barreling of hot mould with casting

Also Published As

Publication number Publication date
EP0003225A1 (fr) 1979-08-08
DE2860732D1 (en) 1981-08-27

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