EP0922120B1 - Revolving furnace for the treatment of work pieces - Google Patents

Abstract

A furnace body (10) houses a treatment rotor (30) which has charge locations (36) to take up a workpiece charge each and is supported so as to be driven in rotation around a central axis (A). The furnace body (10) communicates with side chambers (110, 110') equipped to receive a workpiece charge each from the treatment rotor (30) and to deliver it to the same, respectively. A lock rotor (60) likewise arranged in the furnace body (10) and adapted to be driven in rotation about the central axis (A) comprises at least two lock chambers (64) which are offset angularly relative to each other with respect to the central axis (A). The lock chambers (64) are opened alternately to the surroundings of the furnace body (10) and to a side chamber (110, 110') for reception and delivery of a workpiece charge each. Transfer apparatus (12) are provided for translating a respective workpiece charge between one each of the aforementioned chambers (64, 110, 110') and the treatment rotor, at least one those apparatus being designed for translating a workpiece charge each between the lock rotor (60) and the treatment rotor (30).

Description

• einem Ofengehäuse, das einen Ofenraum umschließt, in dem eine von der Umgebungsluft abweichende Atmosphäre herstellbar ist,
• einem Behandlungsrotor, der im Ofengehäuse um eine zentrale Achse drehantreibbar angeordnet ist und eine Anzahl Chargenplätze zum Aufnehmen je einer Werkstückcharge aufweist,
• Nebenkammern, die an das Ofengehäuse angeschlossen und dazu eingerichtet sind, jeweils eine Werkstückcharge vom Behandlungsrotor zu übernehmen oder an ihn abzugeben,
• mindestens zwei Schleusenkammern, die bezüglich der zentralen Achse gegeneinander winkelversetzt angeordnet und zum Aufnehmen und Abgeben jeweils einer Werkstückcharge abwechselnd zur Umgebung des Ofengehäuses sowie zu einer Nebenkammer geöffnet sind, und
• Umsetzgeräten zum Umsetzen jeweils einer Werkstückcharge zwischen je einer der genannten Kammern und dem Behandlungsrotor.

The invention relates to a rotary cycle furnace for treating workpieces with

• an oven housing which encloses an oven chamber in which an atmosphere deviating from the ambient air can be produced,
• a treatment rotor, which is arranged in the furnace housing such that it can be driven in rotation about a central axis and has a number of batch locations for receiving one batch of work piece each,
• Secondary chambers, which are connected to the furnace housing and are set up to take over a batch of workpieces from the treatment rotor or to deliver them to it
• at least two lock chambers which are arranged at an angle to one another with respect to the central axis and which are open alternately to the surroundings of the furnace housing and to a secondary chamber for receiving and delivering a batch of workpieces, and
• Transfer devices for transferring a batch of workpieces between each of the above-mentioned chambers and the treatment rotor.

Rotary cycle furnaces of this type are particularly suitable for heat treatments, for example for carburizing, nitriding, phosphating and / or hardening metallic workpieces. In a known generic rotary cycle oven (DE 295 05 496 U1), a feed lock arranged outside the furnace housing is accessible through an entrance gate and separated from a heating chamber by a first intermediate gate, which in turn is separated from an equalizing chamber by a second intermediate gate.
The compensation chamber is attached radially on the outside of the furnace housing and separated from the furnace chamber by a third intermediate gate. Workpieces that are to be carburized and then hardened are arranged in batches on a pallet and pushed by transfer devices one after the other through the feed lock, the heating chamber and the compensation chamber into the furnace chamber, for which the gates mentioned are opened one after the other and before the next gate is opened again must be closed so that a desired atmosphere that differs from the ambient air can be maintained in the chambers mentioned and in the furnace chamber. Two carburizing chambers are attached radially from the outside to the furnace housing, offset angularly against the compensation chamber and with respect to one another; these chambers are also separated from the furnace chamber by a normally closed gate. The same applies to a hardening furnace, which is also mounted radially on the outside of the furnace housing. An output lock connects to the hardening furnace and is also set up to quench the workpieces heated to the hardening temperature in the hardening furnace. This known arrangement takes up a relatively large amount of space for a given diameter of the furnace housing and requires considerable maintenance for the numerous gates required for the locks and further chambers.

The same applies to other known rotary ovens the type mentioned at the beginning (DE 40 05 956 C1 and EP 0 198 871 B1).

The invention has for its object a rotary cycle oven for treating workpieces, especially for hardening and Tempering metallic workpieces in a cost and space saving way design and enable him to save time.

• die Schleusenkammern in einem Schleusenrotor angeordnet sind, der ebenfalls im Ofengehäuse angeordnet und um die zentrale Achse derart drehantreibbar ist, daß periodisch jeweils mindestens eine Schleusenkammer zu einer der Nebenkammern hin geöffnet ist, und
• mindestens eines der Umsetzgeräte zum Umsetzen jeweils einer Werkstückcharge zwischen dem Schleusenrotor und dem Behandlungsrotor ausgebildet ist.

The object is achieved based on a rotary cycle oven of the type mentioned in that

• the lock chambers are arranged in a lock rotor, which is likewise arranged in the furnace housing and can be driven in rotation about the central axis such that at least one lock chamber is periodically opened towards one of the secondary chambers, and
• at least one of the transfer devices is configured to transfer a batch of workpieces between the lock rotor and the treatment rotor.

From placing the locks in one with the treatment rotor coaxial lock rotor there is the possibility opening and closing of the lock chambers particularly simple way to control and take up the space to keep the entire arrangement small, even if considerably more than the usual two locks are provided.

• die Anzahl Chargenplätze des Behandlungsrotors, die in einer gemeinsamen Ebene engeordnet sind, ein ganzzahliges Vielfaches der Anzahl Schleusenkammern des Schleusenrotors ist, und
• beide Rotoren schrittweise derart antreibbar sind, daß der Winkelbetrag jedes Schrittes des Schleusenrotors ein ebensogroßes Vielfaches jedes Schrittes des Behandlungsrotors ist.

The two rotors assigned to one another according to the invention are expediently driven separately and at different speeds. The treatment rotor requires a period of time corresponding to the required dwell time of the workpieces for a full revolution; for example, the lock rotor only needs a twelfth of this time for each full revolution. If the angular velocity of both rotors is low, and if the workpiece batches either consist only of a relatively large workpiece or are inserted and removed on trays, pallets or the like, continuous operation of both rotors is possible in principle. In general, however, it is preferable to operate the rotary cycle furnace according to the invention step by step. For this purpose, he is preferably trained in that

• the number of batch locations of the treatment rotor, which are arranged in a common level, is an integer multiple of the number of lock chambers of the lock rotor, and
• both rotors can be driven step by step in such a way that the angular amount of each step of the lock rotor is an equally large multiple of each step of the treatment rotor.

In the event that workpieces are to be treated, each in relatively long periods of different influences should be suspended and for this purpose, for example, in different temperature zones, the rotary cycle furnace according to the invention be further developed in that the treatment rotor has at least two turntables which axially offset from each other, thermally insulated from each other and can be heated differently.

In some cases it is sufficient if at least one secondary chamber a device for cooling each batch of workpieces contains or can be connected to such. The facility a cooling device of known type can be used for cooling, for example a nitrogen shower, an oil bath or the like it is also possible to cool another workpiece Provide turntable. However, the lock rotor is preferred trained to cool the workpieces. To this end a coolant channel can be arranged on the furnace housing over an arc corresponding to at least one step of the Lock rotor extends, separated from adjacent secondary chambers and with at least one along its length the lock chambers is connected.

• das Ofengehäuse eine ringförmige stationäre Dichtfläche, und der Schleusenrotor eine mit ihm rotierende Dichtfläche aufweist, und
• zwischen diesen beiden Dichtflächen ein gegen Drehen festgehaltener Dichtungsring angeordnet ist, in dem zum Hindurchbewegen je einer Werkstückcharge geeignete Durchlässe in gleicher Anzahl und Anordnung wie die Schleusenkammern ausgebildet sind.

The rotary cycle oven according to the invention only needs to be equipped with a single sealing arrangement which seals moving parts against stationary parts. This can be done in such a way that

• the furnace housing has an annular, stationary sealing surface, and the lock rotor has a sealing surface rotating with it, and
• between these two sealing surfaces there is arranged a sealing ring held against rotation, in which passages suitable for moving one batch of work piece each are designed in the same number and arrangement as the lock chambers.

It is also possible to have a stationary one formed on the furnace housing and one trained on or with the lock rotor rotating sealing surface interact directly with each other allow; has a sealing ring arranged according to the invention however the advantage that it is a relatively soft intermediate member represents that is subject to wear and in contrast to produce relatively inexpensive to its two contact partners and can be exchanged quickly. In addition, the sealing ring Compensate concentricity errors and thermal expansion, especially if the trained on the furnace housing and the lock rotor Sealing surfaces are converging and the sealing ring is conical has a corresponding wedge profile and in axial Direction is biased.

• die zentrale Achse senkrecht angeordnet ist,
• jeder der Chargenplätze mehrere Lamellen aufweist, die im wesentlichen radial zur zentralen Achse, jedoch parallel zueinander, hochkant angeordnet sind,
• jede Schleusenkammer einen Schleusenplatz enthält, der von entsprechend angeordneten Lamellen gebildet ist,
• die Umsetzgeräte je einen radial verschiebbaren, zwischen die Lamellen der Chargen- und Schleusenplätze passenden Lamellenkamm aufweisen und
• der Lamellenankamm jedes Umsetzgerätes zwischen Höhenstellungen, die denjenigen der Rotoren entsprechen, heb- und senkbar ist.

The central axis of the rotary cycle oven according to the invention can in principle have any position in space; for example, it can be arranged horizontally if care is taken to ensure that the workpieces to be treated individually or in larger batches, for example placed on trays, are adequately supported in the lock chambers and at the batch locations, for example in a pendulum manner. However, an embodiment of the rotary cycle oven according to the invention has proven to be particularly advantageous in which

• the central axis is arranged vertically,
• each of the batch locations has a plurality of lamellae which are arranged upright essentially radially to the central axis but parallel to one another
• each lock chamber contains a lock place, which is formed by appropriately arranged slats,
• the transfer devices each have a radially displaceable slat comb that fits between the slats of the batch and lock spaces and
• the lamella comb of each transfer device can be raised and lowered between height positions corresponding to those of the rotors.

• mindestens eine Nebenkammer einer weiteren Nebenkammer derart gegenüberliegend angeordnet ist, daß jeweils eine Schleusenkammer und ein Chargenplatz gleichzeitig von diesen beiden Nebenkammern aus zugänglich sind, und
• diese beiden Nebenkammern je eines von zwei Umsetzgeräten enthalten, die derart steuerbar sind, daß eines von ihnen eine Werkstückchrage vom Schleusenrotor zum Behandlungsrotor, und gleichzeitig das andere Umsetzgerät eine Werkstückcharge vom Behandlungsrotor zum Schleusenrotor umsetzt.

The rotary cycle furnace according to the invention can be developed such that

• at least one secondary chamber is arranged opposite another secondary chamber in such a way that a lock chamber and a batch location are simultaneously accessible from these two secondary chambers, and
• these two secondary chambers each contain one of two transfer devices which can be controlled in such a way that one of them converts a workpiece collar from the lock rotor to the treatment rotor, and at the same time the other transfer device converts a workpiece batch from the treatment rotor to the lock rotor.

This enables the two rotors to rotate intermittently to keep their downtimes particularly short. Beneficial Refinements result from the subclaims 8 and 9. With a suitable design of the transfer devices is also continuous rotation of the two rotors is possible.

With the features of claims 10 to 12, the invention Develop the rotary cycle oven in such a way that it is low Expenditure of energy and resources a particularly accurate dosed action on workpieces, especially those to be hardened Workpieces of low mass made of steel.

Fig. 1

eine teilweise als waagerechter Schnitt I-I in Fig.3 gezeichnete Draufsicht einer ersten Ausführungsform eines erfindungsgemäßen Rundtaktofens;

Fig. 2

den Schnitt in der waagerechten Ebene II-II in Fig.3;

Fig. 3

den senkrechten Schnitt III-III in Fig.2;

Fig. 4

den senkrechten Schnitt IV-IV in Fig.2;

Fig. 5

einen stark vergrößerten Ausschnitt aus Fig.4;

Fig. 6

den senkrechten Schnitt VI-VI in Fig.5;

Fig. 7

eine zweite Ausführungsform eines erfindungsgemäßen Rundtaktofens im waagerechten Schnitt VII-VII in Fig.9;

Fig. 8

den senkrechten Schnitt VIII-VIII in Fig.7;

Fig. 9

den senkrechten Schnitt IX-IX in Fig.7;

Fig. 10

eine teilweise als waagerechter Schnitt X-X in Fig.11 gezeichnete Draufsicht einer dritten Ausführungsform eines erfindungsgemäßen Rundtaktofens;

Fig.11

den senkrechten Schnitt XI-XI in Fig.10;

Fig.12

den senkrechten Schnitt XII-XII in Fig.10;

Fig.13

den senkrechten Schnitt XIII-XIII in Fig.10; und

Fig.14

eine Abwandlung von Fig.13.

Exemplary embodiments of the invention are explained in more detail below with the aid of schematic drawings. The drawings show:

Fig. 1

a top view, partly as a horizontal section II in FIG. 3, of a first embodiment of a rotary cycle oven according to the invention;

Fig. 2

the section in the horizontal plane II-II in Figure 3;

Fig. 3

the vertical section III-III in Fig.2;

Fig. 4

the vertical section IV-IV in Figure 2;

Fig. 5

a greatly enlarged section of Figure 4;

Fig. 6

the vertical section VI-VI in Fig.5;

Fig. 7

a second embodiment of a rotary cycle oven according to the invention in the horizontal section VII-VII in Figure 9;

Fig. 8

the vertical section VIII-VIII in Figure 7;

Fig. 9

the vertical section IX-IX in Figure 7;

Fig. 10

a top view, partly as a horizontal section XX in FIG. 11, of a third embodiment of a rotary cycle oven according to the invention;

Fig. 11

the vertical section XI-XI in Fig.10;

Fig. 12

the vertical section XII-XII in Fig.10;

Fig. 13

the vertical section XIII-XIII in Fig.10; and

Fig. 14

a modification of Fig. 13.

The rotary cycle furnace shown in Fig. 1 to 6 has a furnace housing 10 with an essentially cylindrical outer wall 12, an underbody 14 and an intermediate floor 16, which together enclose an evacuable furnace chamber 20, also with a Cover 18 and with a lower housing part 22, which with the outer wall 12 and the underbody 14 consists of one piece.

At the intermediate floor 16 is an upwardly projecting cylindrical Collar 24 formed in which by means of radially inner bearing 26th a hub 28 of a treatment rotor 30 around a vertical central one Axis A is rotatably mounted. The treatment rotor 30 has as essential components an upper turntable 32 and a lower turntable 34, both of which are annular and numerous, in the example shown seventy-two, batch locations 36 or 38 have. Each of the batch places 36 and 38 is made up of several horizontal, upright slats 40 formed, which are parallel to each other and essentially Extend radially from the central axis A and through a common annular bottom plate 42 held together are.

The treatment rotor 30 also includes three coaxially central axis A insulating plates 44 arranged one below the other, 46 and 48, with the upper batch locations 36 between the upper and the middle insulating plate 44 and 46, respectively, and the lower ones Batch places 38 between the middle and the lower insulating plate 46 and 48 are arranged such that on each Batch location a batch of workpieces to be treated W space Has. The insulating plates 44, 46 and 48 are preferably composite plates, each made of two thin ceramic plates and three thick insulating plates are composed of hard graphite felt. All of the plates 42 to 48 mentioned are axially parallel Tie rod 49 rigidly but interchangeably connected to the hub 28. The treatment rotor 30 thus constructed is by means of a Motor 50 can be driven in rotation about the central axis A step by step. Given the number of seventy-two chosen as an example Batch positions 36 and 38 on each of the two turntables 32 and 34, each step extends over 5 °. So that step size is strictly observed, the motor 50 is preferably a Servo motor with built-in, backlash-free reduction gear, for example cyclo transmission.

The batch locations 36 of the upper turntable 32 are between two annular heating discs concentric to the central axis A. 52 arranged for high temperature heating; in corresponding The batch locations 38 of the lower turntable are wise 34 between two heating disks 54 for low temperature heating arranged. All heating disks 52 and 54 are star-shaped according to the arrangement of batch locations 36 and 38 serrated, preferably consist of molybdenum or graphite and are connected to a via a central slip ring assembly 56 electrical power source connected. Below the slip ring arrangement 56 is the furnace housing 10 with a cup-shaped Closure 58 completed.

Above the treatment rotor 30, through the intermediate floor 16 of separated from it, a lock rotor 60 is arranged in the furnace housing 10, which also on the collar 24 by means of outer bearings 62 stored and driven to rotate about the central axis A. The Lock rotor 60 has several, six in the example shown, Lock chambers 64, which are at angular intervals of 60 ° to each other offset in a spoke-like part of the lock rotor formed and in the embodiment shown in Fig.1 to 6 are only open radially to the outside. On the outside wall 12 of the furnace housing 10 are in the direction of rotation C against each other offset a first, second and third suction nozzle 66, 67 and 68 arranged to evacuate the lock chamber a suction pump can be connected.

Horizontal slats 70 are upright in each lock chamber 64 arranged, which are at the same mutual distance as the fins 40 parallel to one another essentially radially from extend away from the central axis A and through a base plate 72 are interconnected. The bottom plates 72 of the lock rotor 60 as well as the bottom plates 42 of the treatment rotor 30 the task of vibrating the associated slats 70 or 40, especially with rapid acceleration or Braking the lock rotor 60 or treatment rotor 30, too prevent. The fins 70 in each of the lock chambers 64 form a lock place 74 on which a batch of workpieces W is deductible.

For example, each batch consists of five radially in a row arranged annular workpieces W, e.g. Ball bearing rings. In the event that the workpieces to be treated W balls are, the slats 40 and 70, as in Fig.5 on one of the slats 70 indicated, on their top with one Notch 75 provided so that each ball in notches two adjacent Slats can be safely accommodated. But it is it is also possible to arrange the workpiece batches on a pallet.

Around the lock rotor 60 there is a stationary one on the furnace housing 10 Sealing surface 76 formed in the shape of an inner cone, 5 has its smallest diameter at the bottom. The Lock rotor 60 also has a conical outer sealing surface 78, which has its largest diameter below and preferably is ceramic coated. Between the sealing surfaces 76 and 78 a correspondingly conical sealing ring 80 is arranged, which in profile has the shape of a wedge tapering downwards has, preferably essentially made of graphitized coal or semi-crystalline thermoplastic (PEEK), and there is outer conical surface one on the stationary sealing surface 76 has adjacent elastomer coating, while it on the outer sealing surface 78 of the lock rotor 60 is in direct contact. The sealing ring 80 is attached to it by means of a to the central axis A parallel pin 82 which in a Recess 84 of the lid 18 engages, prevented from rotating and is axially downward by means of springs 86 supported on the cover 18 biased. According to FIG. 2, there are six in the sealing ring 80 Passages 88 formed, which are at angular intervals of 60 ° to each other are offset and whenever the lock rotor 60 stands still, with one of the lock chambers 64 swear.

The lock rotor 60 is stepped by means of two motors 90 drivable; for the number of six lock chambers 64 extend over each step 60 °. The two motors 90, preferably electric servomotors, are arranged offset from each other by 180 ° and have each a backlash-free reduction gear with a pinion 91, the free of play in a ring gear arranged on the lock rotor 60 92 engages.

The outer wall 12 of the furnace housing 10 is thermally insulated, e.g. with hard graphite felt, and points at the level of the lock rotor 60 six radial openings 94 offset from one another by 60 ° on, each with one of the passages 88 of the sealing ring 80th swear. In the area of one of the openings 94 is on the outer wall 12 of the furnace housing 10 radially from the outside a panel 96 grown, the height of the lock rotor 60 through Slots 98 open to the outside of the furnace housing 10 is. A charger 100 is located inside the casing 96 Introducing and removing batches of workpieces in and out the lock chambers 64 arranged. The charger 100 has one Lamellar comb 102, which is between each of the lock places 74 forming fins 70 of the lock rotor 60 fits. The lamella comb 102 is slight along a vertical pivot axis B. can be raised and lowered and about this pivot axis B from one with respect to the central axis A radial position after both Directions, through one of the slots 98 of the panel 96 through, can be swiveled outwards by 90 ° and is on one Carriage 104 arranged radially to the central axis A is slidable to and from it. For lifting and lowering a lift drive 105, a swivel drive 106 for pivoting, and a displacement drive 108 is provided for radial displacement; these three drives can also each have an electric servo motor exhibit.

The five remaining openings 94 in the outer wall 12 of the furnace housing 10 open in the embodiment shown in Fig.1 to 6 of the rotary cycle oven in each an auxiliary chamber 110, the is hermetically sealed to the outside and a transfer device 112 contains. Each of the total of five transfer devices 112 has one Slat comb 114, which corresponds to the slat comb 102, however in contrast to this, always arranged radially, for that but along a vertical column 116 between height positions is adjustable, those of the two turntables 32 and 34 and the lock chambers 64 correspond. The column 116 is mounted on a carriage 118, which by means of a motor 120 adjustable radially to the central axis of rotation A and away from it is. The motor 120 drives a nut that reciprocates movement of a hollow attached to the carriage 118 Spindle 122 generated. Another is for lifting movements Motor 124 is provided, which is flange-mounted on the motor 120 and drives a shaft 126. The shaft 126 extends extends through the hollow spindle 122 and drives in turn a vertical spindle 128, which with the lamellar comb 114 is threaded to lift and close reduce.

At least one of the secondary chambers 110 can have a device 130 for cooling or quenching the previously heated workpieces W contain; this device 130 can, as in the right part of FIG Fig.4 indicated, be designed so that by the relevant Secondary chamber 110 a cooling gas, for example nitrogen, can be passed through. Alternatively, as a facility an oil bath to quench in one of the subchambers 110 be provided.

In the first secondary chamber 110, which in the direction of arrow C in Figure 2 follows the panel 96, in addition to the opening 94 connecting it to lock rotor 60 also has an opening additional opening 132 formed in the outer wall 12, which connects this secondary chamber with the upper turntable 32. An opening 134 opens into the last secondary chamber 110 connects them to the lower turntable 34. All openings 94, 132 and 134 in the outer wall 12 of the furnace housing 10 and the passages 88 of the sealing ring 80 are dimensioned so that one of the lamellar combs 102 or 114 between the fins 40 of the treatment rotor 30 or between the fins 70 of the lock rotor 60 can be inserted.

The rotary cycle furnace shown in Fig. 1 to 6 works as follows:
The lamella comb 102 of the charger 100 is pivoted out of the casing 96 according to FIG. 2, for example clockwise, and is loaded with a batch of workpieces W. This can be done by placing the workpieces W directly on the lamellar comb 102 or by placing them on a pallet or by placing them on a tray which is then taken over by the lamellar comb 102. Then the lamellar comb 102 is pivoted together with the workpiece batch into its radial normal position and then, with the lock rotor 60 at a standstill, moved radially inward into the lock chamber 64 which is just radially aligned with the lamellar comb 102. In the meantime, the lamella comb 102 assumes a height position which lies somewhat above the upper edges of the lamella 70. As soon as the lamella comb 102 has reached its radially inner position, it is lowered to such an extent that the batch of workpieces is placed on the lamellae 70, and thus on the lock place 74 of the lock chamber 64 in question.

The lamella comb 102 is then pulled back radially outwards, and the lock rotor 60 is moved one step, So in the example shown rotated by 60 °, for example counterclockwise, as indicated in Fig.2 with the arrow C. Meanwhile, the one with the first batch of workpieces moves occupied lock chamber 64 on the first suction port 66 over; this lock chamber 64 is thus evacuated State in the position in which it is with the first Secondary chamber 110 is aligned. The transfer device 112 arranged there fetches the batch of workpieces radially from the lock chamber mentioned 64 out, moving it down to the plane of the upper turntable 32, pushes the workpiece batch in a radial Direction in this turntable and sets it at a minor further downward movement on one of its batch places 36 from. Then the treatment rotor 30 by one Step rotated by 5 °.

This sequence of operations is carried out with successive lock chambers 64 of the lock rotor 60 and with successive Batch places 36 of the upper turntable 32 repeated as long as until it is complete, in the example shown with a total seventy-two batches of workpieces.

As soon as the first placed on the upper turntable 32 Batch of workpiece on one full revolution of the treatment rotor 30 took part and from the two upper heating discs 52 to a specific, for example sufficient for hardening, Temperature has been heated, that will be in the first Secondary chamber 110 arranged conversion device 112 used to this Workpiece batch from its batch location 36 on the upper turntable 32 to take off and in the above, just released Deposit lock chamber 64 so that this heated workpiece batch at the next step of the lock rotor 60 in reaches a position opposite the second secondary chamber 110, 2 in the direction of arrow C in FIG follows. The transfer device 112 arranged there fetches the workpiece batch out of the lock rotor 60 so that they have a nitrogen shower exposed or immersed in an oil bath so that the workpieces W of the batch under consideration are quenched.

The batch of workpieces under consideration is then replaced by the same, in the second auxiliary chamber 110 arranged conversion device 112 again dropped off at the same empty lock place 74, and the Lock rotor 60 is rotated by a further step. The viewed workpiece batch thus reaches the radial area inside the third subchamber 110, from there arranged transfer device 112 taken over in the third secondary chamber 110 further cooled and then back to its previous one Returned to Schleusenplatz 74. After another step of the lock rotor 60, the workpiece batch in question in the fourth sub-chamber 110 further cooled and if necessary then brought back to her previous lock place 74.

In the next step of the lock rotor 60, it now arrives adequately cooled batch of workpieces to the fifth secondary chamber 110. The lock chamber 64 moves on the way there, which contains this batch of workpieces, on the second suction port 67 over and is thereby removed from the coolant contained in it, e.g. Nitrogen, or free from oil vapors. The material batch considered is then by means of the in the fifth subchamber 110 arranged transfer device 112 from its lock chamber 64 brought out and on a batch space 38 of the lower turntable 34 discontinued. This sequence of processes is repeated as often as until the lower turntable 34 is also complete with workpiece batches is busy.

On the lower turntable 34, the one under consideration and each one following workpiece batch again at a full revolution of the Treatment rotor 30 part heated to a tempering temperature to become. Then each individual batch of workpieces from the transfer device 112 picked up in the fifth secondary chamber 110 and on the vertically above the lower batch space it has previously occupied 38 lock space ready and just vacated 74 discontinued. Finally, the one considered and each one following workpiece batch at a last step of the lock rotor 60 parts, which, bypassing the third suction port 68, gets back into the working area of the charger 100, picked up by this and out of the panel 96 after is brought outside.

The rotary cycle oven according to Fig. 7 to 9 differs from in Fig. 1 to 6 embodiment shown in that Treatment rotor 30 and the lock rotor 60 radially outside are stored; their bearings 26 and 62 are on the outer wall 12 the furnace housing 10 is arranged. The space radially inside the two rotors 30 and 60 is used to house the fairing 96 with the charger 100 and the five secondary chambers 110 each one of the transfer devices 112 used. The charger 100 and the Conversion devices 112 are according to FIGS. 7 to 9 compared to FIG. 1 up to 6 arranged in reverse; the lamellar combs 102 and 114 are So with the free ends of their slats directed radially outwards. The sealing ring 80 seals against a cylindrical one Inner wall 136 of the furnace housing 10, and in this are the Openings 94, 132 and 134 are arranged. The lock chambers 64 are open radially inwards according to Fig. 7 to 9. Accordingly lock positions 74 and batch positions 36 and 38 radially from the inside to the outside with one workpiece batch each loaded and emptied in the reverse direction.

The cladding 96 forms a feed channel 138, which is above of the cover 18 of the furnace housing 10 extends radially outwards. In the feed channel 138 there is a rotating body 140 by means of a Motors 142 gradually by 180 ° around a vertical Rotation axis D rotatably arranged. The rotating body 140 has two Lamella arrangements 144 diametrically opposite one another in which the lamella comb 102 of the charger 100 radially can be inserted. The charger 100 works with the rotating body 140 for depositing and removing workpiece batches in the same Way together as with the lock rotor 60. The mode of operation of the rotary cycle furnace shown in Fig. 7 to 9 is otherwise analogously the same as described with reference to FIGS. 1 to 6 has been.

In the rotary cycle oven shown in Fig. 10 to 14, this has Furnace housing 10 in addition to the upper intermediate floor 16 lower shelf 17. The upper turntable 32 of the treatment rotor 30 is between the two intermediate floors 16 and 17 arranged in an evacuable part of the furnace space, and the lower turntable 34 is between the underbody 14 and the lower shelf 17 in a normally not evacuated but with atmospheric air or with an inert one Gas like nitrogen-filled part of the furnace chamber 20 is arranged. The two turntables 32 and 34 are sealed against one another, thermally insulated from each other and heatable independently of each other. Each of the two motors 50 drives two pinions 51 according to FIG. each with a ring gear on the top or bottom Turntable 32 or 34 is in constant engagement.

Instead of one of two through the lower one, as shown Intermediate floor 17 separate parts of the furnace space 20, the two turntables 32 and 34 each be a double disc arrangement, which against the Oven housing 10 is sealed and each one delimited Forms part of the furnace chamber 20. In this case it is sufficient if the treatment rotor 30, as in those shown in Fig.1 to 9 Embodiments, only a common ring gear for has both turntables 32 and 34 and the motors 50 accordingly only drive one pinion 51 each.

The lock rotor 60 also has the one shown in FIGS. 10 to 14 Embodiment six lock chambers 64, the arranged at angular intervals of 60 °, however, in contrast to the previous exemplary embodiments are open radially outwards and radially inwards. Rings around the lock rotor 60 is a stationary one on the furnace housing 10 radially outer sealing surface 76 in the form of an inner cone, which has its smallest diameter below. Concentric there is also a stationary one on the furnace housing 10 radially inner sealing surface 76 'in the form of an outer cone, which has its largest diameter below. The lock rotor 60 also has a conical radially outer sealing surface 78, which has its largest diameter at the bottom, and a conical one radially inner sealing surface 78 ', the smallest diameter has down. A corresponding is between the sealing surfaces 76 and 78 conical outer sealing ring 80 arranged in the Profile has the shape of a wedge tapering downwards. Between the sealing surfaces 76 'and 78' is a sealing ring 80 corresponding, but smaller in diameter inner Sealing ring 80 'arranged. Each of the sealing rings 80 and 80 'is attached to the central axis A parallel key 160 or 160 ', which in a corresponding Recess 84 or 84 'of the cover 18 engages, prevented from rotating and is guided by means of pressure gas in the cover 18, e.g. Nitrogen, loaded piston 162 or 162 'axially biased downwards.

For loading and emptying and for evacuating the lock chambers 64 are four outer in the outer seal ring 80 radial passages 88 formed, which are at angular intervals of 60 ° offset from each other in the upper half according to Fig.10 of the outer sealing ring 80 are arranged and always when the lock rotor 60 is stationary, with one of the lock chambers 64 are cursed. The inner sealing ring 80 'has two inner radial passages diametrically opposite each other 88 ', which are aligned with one of the outer passages 88. In addition, the sealing rings 80 and 80 'have their in accordance Fig.10 lower area a larger number of closely consecutive Slots 146 and 146 'for introducing and discharging a Coolant into and out of the lock chambers 64.

The outer wall 12 of the furnace housing 10 has the level of the lock rotor 60 four outer ones offset by 60 ° each radial openings 94, each with one of the passages 88 of the outer sealing ring 80 are aligned. The inner wall 136 of the furnace housing 10 has two inner radial at the level of the lock rotor 60 Openings 94 'arranged diametrically opposite one another and with one of the passages 88 'of the inner sealing ring 80 'aligned. Around two of the outer openings 94 is on the outer wall 12 of the furnace housing 10 radially from the outside ago a panel 96 is attached, which is at the level of the lock rotor 60 through a slot 98 to the outside of the furnace housing 10 is open. Inside the panels 96 one charger 100 each for inserting and removing workpiece batches arranged in or out of the lock chambers 64.

The other two, diametrically opposite, openings 94 in the outer wall 12 of the furnace housing 10 each open an outer secondary chamber 110, which is hermetically sealed to the outside and contains an external converter 112. The Inner wall 136 of the furnace housing 10 encloses two inner secondary chambers 110 ', separated by a vertical partition 148 are separated and one of two diametrically opposite each other contained opposite conversion devices 112 '.

Each of the four conversion devices 112 and 112 'has one Lamellar comb 114 or 114 'on which the lamellar combs 102 of the Chargers 100 corresponds, but in contrast to them constantly arranged radially, but along a vertical column 116 or 116 'is adjustable between height positions, the those of the upper and lower turntable 32 and 34 and the Lock chambers 64 correspond. The columns 116 and 116 'are attached to a carriage 118 or 118 ', which by means of a motor 120 or 120 'radially towards the central axis of rotation A. and adjustable from it. Each of the motors 120 and 120 ' drives a mother making a reciprocating motion a hollow attached to the associated slide 118 or 118 ' Spindle 122 or 122 'generated. Another is for lifting movements Motor 124 and 124 'provided the coaxially to the Motor 120 or 120 'is flanged and a shaft 126 or 126 'drives. The shaft 126 and 126 'extends through the associated hollow spindle 122 or 122 'and drives in turn a vertical spindle 128 or 128 ', with the associated lamella comb 114 or 114 'in threaded engagement stands to raise and lower it.

In the outer secondary chamber arranged on the left according to FIGS. 10 and 11 110 opens out in addition to that connecting it to the lock rotor 60 upper outer opening 94 also in the outer wall 12 formed central outer opening 132 through which this outer secondary chamber 110 accessible from the upper turntable 32 is. Aligned with this central outer opening 132 a central inner opening formed in the inner wall 136 132 'through which the upper turntable 32 from the inner sub-chamber 110 'is accessible from. 10 and 11 outer subchamber 110 arranged on the right opens into a lower one outer opening 134 through which the lower turntable 34 is accessible is. With this lower outer opening 134 is aligned lower inner opening 134 'formed in inner wall 136 through which the lower turntable 34 from the inner sub-chamber 110 'is accessible from. All openings 94, 94 ', 132, 132', 134 and 134 'of the furnace housing 10 and the passages 88 and 88 'of the sealing rings 80 and 80' are dimensioned so that they are radial one of the lamella combs 102 and 114 passes through them or 114 'between the fins 40 of the treatment rotor 30 or can be inserted between the fins 70 of the lock rotor 60 is.

The outer secondary chamber arranged on the left according to FIGS. 10 and 11 110 and the associated inner secondary chamber 110 'are constantly on with the upper turntable 32 in connection and are just like the associated part of the furnace chamber 20 is constantly evacuated during operation. The right outer subchamber 110 and the associated one inner secondary chamber 110 ', however, are in constant communication with the lower turntable 34 and the part surrounding it of the furnace chamber 20 and therefore contain the one prevailing there Atmosphere, e.g. are called nitrogen, with which the workpieces Tempering temperature can be brought.

The transfer device 112 in the left outer according to FIGS. 10 and 11 Sub-chamber 110 is equipped with a heating plate 150 which is arranged at a distance above the lamella comb 114 and heated the workpieces lying on it from above, e.g. electro-inductive or by heat radiation.

In the third exemplary embodiment illustrated in FIGS. 10 to 14 A rotary indexing oven is different from the first and second embodiment for quenching the workpieces W a device with coolant supply channels 152 and 152 'is provided, which extend along the outer wall 12 or inner wall 136 of the furnace housing 10 over a very wide angular range of extend about 160 ° in the circumferential direction so that they are continuous with two, sometimes even three, successive lock chambers 64 have connection and this with coolant, e.g. cold nitrogen, supply. The coolant is through coolant discharge channels 154 and 154 'derived after having the flows through them in related lock chambers 64 Has. The slots 146 and 146 'extend from these channels or open into it, extend through the furnace wall 12 or 136 and the sealing ring 80 and 80 'and allow the simultaneous flow through all lock chambers 64, covering the area between the coolant supply channels 152, 152 ' and the coolant discharge channels 154 arranged therebetween, 154 'go through.

The lock place 74 of each lock chamber 64 is according to FIG. 13 and 14 enclosed by an interchangeable sleeve 156 which extends radially to the central axis A, radially inside and is open on the outside, consists of perforated sheet metal and the associated slats 70 wears. The environment of the sleeve 156 is in each case on the Coolant supply channels 152, 152 ', and the interior of the sleeve 156 connected to the coolant discharge channels 154, 154 'as long as the lock chamber 64 concerned the angular range described through these channels.

The rotary cycle furnace shown in Fig. 10 to 14 works as follows:

The lamella comb 102 of the left according to FIGS. 10 and 12 Charger 100 is pivoted out of the associated panel 96 and loaded with a batch of workpieces W; then the lamellar comb 102 is pivoted into its normal radial position and radially inward into that lock chamber 64 retracted, just aligned radially on this lamella comb 102 is. Then the batch of workpieces is in the lock place 74 of the lock chamber 64 in question and the said lamella comb 102 is retracted radially outward.

The lock rotor 60 is then moved one step, in example shown by 60 °, in the direction of arrow C in Fig. 10 rotated. This moves with the first batch of workpieces occupied lock chamber 64 past suction port 66, which is arranged on the outer wall 12 of the furnace housing 10 and on a suction pump is connected. The said lock chamber 64 thus reaches the position in the evacuated state, in which they with the left outer secondary chamber according to Fig.10 and 11 110 and simultaneously with the left inner secondary chamber 110 'has connection. The transfer device arranged in the latter 112 'fetches the workpiece batch radially out of the lock chamber mentioned 64 out, moving it down to the plane of the upper turntable 32, pushes the workpiece batch radially outside in this turntable and sets it at a minor further downward movement on one of its batch places 36 from. Then the treatment rotor 30 by one Step rotated by 5 °.

This sequence of operations is carried out with successive lock chambers 64 of the lock rotor 60 and with successive Batch places 36 of the upper turntable 32 repeated as long as until it is complete, in the example shown with a total seventy-two batches of workpieces.

As soon as the first placed on the upper turntable 32 Batch of workpiece on one full revolution of the treatment rotor 30 has participated and in doing so on a specific, for example temperature necessary for hardening has been heated, the transfer device 112 is arranged on the left in accordance with FIGS. 10 and 11 outer subchamber 110 used to hold this batch of workpiece from their batch location 36 on the upper turntable 32 to lift them off by means of the heating plate 150 to hardening temperature and hold them in the lock chamber 64 above to drop off at Schleusenplatz 74. This lock chamber 64 has become free by the fact that the one working at the same time Transfer device 112 'in the left inner secondary chamber 110' untreated workpiece batch from this lock chamber to has just brought vacant batch number 36.

The heated workpiece batch arrives at the next step of the Lock rotor 60 in the effective range of the coolant supply channels 152, 152 ', so that the workpieces W of this batch be put off, taking because of the long while almost three steps of the lock rotor 60 the coolant to a relatively low temperature, e.g. can be cooled to 5 ° C.

In the fourth step of the lock rotor 60, it now arrives sufficiently cooled workpiece batch in a position between 10 and 11 the right outer secondary chamber 110th and the right inner subchamber 110 '. There is the considered Batch of material from in the right inner side chamber 110 'arranged inner conversion device 112' from their Lock chamber 64 removed and in a batch space 38 of the lower turntable 34. This sequence of operations will repeated until the lower turntable 34 is also complete, in the example shown with seventy-two workpiece batches, is busy.

As soon as the first placed on the lower turntable 34 Workpiece batch again at a full revolution of the treatment rotor 30 has participated and in doing so focuses on a specific for example, the temperature necessary for tempering has been heated is this batch of workpieces from the transfer device 112 in the 10 and 11, right outer chamber 110 picked up from their batch location 38 at the lower turntable 34 and on the lock space above, just vacated 74 discontinued.

This lock chamber 64 with its lock place 74 is thereby released that the simultaneously operating transfer device 112 'in the right inner secondary chamber 110' a quenched Workpiece batch from this lock place to the one just released Lot 38 has brought.

Finally, take the one considered and the first one loading the furnace Workpiece batch in a sixth step of the lock rotor 60 parts, whereby they, past the suction port 68, in the working area of the charger arranged on the right in accordance with FIG. 1 100 arrives, picked up by this and from the associated Cover 96 is pivoted outwards.

This completes the furnace filling with batches of workpieces - In the example shown, this takes about 22 minutes - and it starts at intervals of only 9 seconds each a workpiece batch in the finished heat-treated state Leaving furnace while continuing at the same intervals One batch of untreated workpiece is fed to the furnace becomes. The whereabouts of the workpiece batches on the two Turntables of the treatment rotor last in the example shown 10.8 minutes each. Before converting and / or repairs the The procedure is the reverse of that of filling the oven of emptying from the workpiece batches, it would be shown in the Example also take about 22 minutes.

The rotary cycle oven according to the invention almost enables one continuous, fully automatic and in the production line fully integrable and linkable heat treatment process as well a product-related increase in quality and quantity.

Claims (12)

1. A revolving transfer furnace for treating workpieces (W), comprising

   a furnace body (10) enclosing a furnace chamber (20) adapted for an atmosphere which differs from the ambient air to be established inside said chamber,

   a treatment rotor (30) arranged in the furnace body (10) so as to be driven in rotation about a central axis (A) and comprising a number of batch locations (36) to each take up a batch of workpieces,

   side chambers (110) connected to the furnace body (10) and designed each for receiving a batch of workpieces from the treatment rotor (30) or for delivering one to the same,

   at least two lock chambers (64) disposed angularly offset relative to each other with respect to the central axis (A) and being opened alternately to the surroundings of the furnace body (10) and to a side chamber (110) so as to each receive and deliver a batch of workpieces, and

   transfer apparatus (112) for transferring a batch of workpieces each between a respective one of the aforementioned chambers (64, 110) and the treatment rotor (30),

   characterized in that

   the lock chambers (64) are located in a lock rotor (60) which likewise is arranged in the furnace body (10) and adapted to be driven in rotation about the central axis (A) such that at least one lock chamber (64) each is periodically opened towards one of the side chambers (110), and

   at least one of the transfer apparatus (112) is designed to transfer one batch of workpieces each between the lock rotor (60) and the treatment rotor (30).
2. The revolving transfer furnace as claimed in claim 1,
   characterized in that

   the number of batch locations (36) of the treatment rotor (30) located in a common plane is an integer multiple of the number of lock chambers (64) of the lock rotor (60), and

   both rotors (30, 60) are adapted to be driven stepwise in rotation such that the angular dimension of each step of the lock rotor (60) is the same size multiple of each step of the treatment rotor (30).
3. The revolving transfer furnace as claimed in claim 1 or 2, characterized in that the treatment rotor (30) comprises at least two turntables (32, 34) which are axially offset with respect to each other, thermally insulated from each other, and adapted to be heated differently.
4. The revolving transfer furnace as claimed in one of claims 1 to 3, characterized in that at least one coolant channel (152, 154; 152', 154') is arranged at the furnace body (10) so as to extend through an arc corresponding to at least one step of the lock rotor (60) and is separated from adjacent side chambers (110; 110') and communicates throughout its arc length with at least one of the lock chambers (64).
5. The revolving transfer furnace as claimed in one of claims 1 to 4, characterized in that

   the furnace body (10) comprises at least one annular, stationary sealing surface (76; 76') and the lock rotor (60) comprises a co-rotating sealing surface (78; 78'), and that

   a sealing ring (80; 80') which is fixed against rotation is disposed between those two sealing surfaces (76, 78; 76', 78') and formed with suitable passages (88), being the same in number and arrangement as the lock chambers (64), to permit a batch of workpieces each to pass.
6. The revolving transfer furnace as claimed in one of claims 1 to 5, characterized in that

   the central axis (A) is disposed vertically,

   each batch location (36) comprises a plurality of fins (40) which are disposed substantially radially with respect to the central axis (A) but parallel to one another and essentially on edge,

   each lock chamber (64) includes a lock location (74) formed by fins (70) which are arranged accordingly,

   the transfer apparatus (112) each comprise a radially displaceable fin comb (114) which fits between the fins (40, 70) of the batch and lock locations (36, 74), and

   the fin comb (114) of each transfer apparatus (112) is adapted to be raised and lowered between positions in height corresponding to those of the rotors (30, 60).
7. The revolving transfer furnace as claimed in one of claims 1 to 6, characterized in that

   at least one side chamber (110) is disposed opposite another side chamber (110') such that one and the same lock chamber (64) as well as one and the same batch location (36) each are simultaneously accessible from these two side chambers (110, 110'), and

   these two side chambers (110, 110') contain one each of two transfer apparatus (112, 112') which are controllable such that one of them will transfer a batch of workpieces from the lock rotor (60) to the treatment rotor (30) while the other one, at the same time, translates a batch of workpieces from the treatment rotor (30) to the lock rotor (60).
8. The revolving transfer furnace as claimed in claim 7,
   characterized in that

   both rotors (30, 60) are annular, and

   at least one inner side chamber (110') is disposed radially within the two rotors (30, 60).
9. The revolving transfer furnace as claimed in claim 8, in combination with claim 3, characterized in that

   the inner side chamber (110') includes two inner transfer apparatus (112') which face diametrically away from each other,

   an outer transfer apparatus (112) each, located in a side chamber (110) each, is associated with a respective one of the two inner transfer apparatus (112') in radially opposed relationship,

   one of the inner transfer apparatus (112') and the respective radially opposed outer transfer apparatus (112) are provided for transferring batches of workpieces between the lock rotor (60) and one of the turntables (32), and

   the other inner transfer apparatus (112') and the respective radially opposed outer transfer apparatus (112) are provided for transferring batches of workpieces between the lock rotor (60) and the other turntable (34).
10. The revolving transfer furnace as claimed in claim 9,
    characterized in that the two turntables (32, 34) are sealed with respect to each other so that a different atmosphere can be maintained at the batch locations (36) of the first turntable (32) from that at the batch locations (38) of the second turntable (34).
11. The revolving transfer furnace as claimed in claim 9 or 10, characterized in that at least the side chamber (110) provided for transferring the workpieces (W) from the first turntable (32) to the lock rotor (60) comprises a heater by means of which a substantial drop in temperature of the workpieces (W) as early as during transferring can be prevented.
12. The revolving transfer furnace as claimed in claim 11,
    characterized in that the transfer apparatus (112) in the heatable side chamber (110) comprises a heater plate (150).

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