EP0973001B1 - Process for fastening or removing a load in a heat treatment installation with a bottomless furnace - Google Patents

Abstract

A method for coupling and uncoupling a charge in a heat treatment installation consists of coupling and uncoupling the charge by transmitting a relative translational movement between a treatment station (1) and some means for charging and discharging (20). The installation comprises at least one treatment station (1) incorporating an opening (4) oriented towards the bottom and destined to receive the charge (6). There is a member for charging and discharging the charge allowing, via a support mechanism (8), the charging of the charge (6) onto and the discharging of the charge from an anchoring mechanism (16) arranged in the treatment station (1).

Description

The present invention relates to a method hooking and unhooking of a load in a heat treatment facility, and more particularly in such an installation comprising a oven having an opening facing downwards.

The present invention also relates to a thermal treatment installation allowing the setting in work of this process.

Conventional heat treatment systems have one or more ovens with an opening facing downwards, generally referred to as bell ovens and means for loading and unloading the parts or loads to be treated in and from the oven (s).

Charges are loaded into the ovens generally as follows: the load is placed on a support plate in the form of a rigid grid honeycomb plane placed on an elevator which is movable between two positions respectively low and high. The oven has studs or brackets in its lower part retainers that protrude radially from the inner wall of the oven. These studs give opening the oven an indented outline. Grid has a complementary outline and dimensions slightly smaller than those of the opening from the oven, so that the grid can pass smoothly with the load through the opening. So the grid with the load can be inserted from the bottom, in the oven opening by the elevator while the grid is oriented parallel to this opening. When the grid is brought by the elevator to a level higher than that of the studs, we print a relative movement of the grid with respect to the studs so that the grid can then come to rest on the studs when lowering the elevator.

The load release operation is carried out simply by repeating the above process so reverse.

In some installations, it is the grid itself which is pivoted relative to the studs. Such an installation is disclosed by EP-A- 671 476. In this first case, it is necessary to provide risers equipped with means allowing the rotation of the grid this which increases the cost of making the elevator.

In other installations, it is the internal wall or oven bell which is pivoted relative to the rack. In this second case, it is necessary to provide a complex arrangement allowing the rotation of the bell to very high temperatures. However, at these temperatures, it thermal expansion phenomena occur significant and deformities of the organs under constraints which induce dysfunctions, notably seizures, which makes these installations little reliable.

The main aim of the invention is therefore to remedy the disadvantages of the aforementioned prior art in providing a process and an installation which allow to carry out in a simple and economical way the hanging and unhooking a load in and from an oven, without addition of rotation system on an elevator and without organ movement in a temperature environment high.

To this end, the subject of the invention is a method in accordance with that defined by claim 1. The invention also relates to an installation for the implementation of the above process and in accordance with that described in claim 5.

• les figures 1a à 1c représentent des vues en coupe partielle de l'installation de traitement thermique illustrant les étapes d'accrochage d'une charge dans une station conformément au procédé selon l'invention,
• les figures 2a et 2b représentent des vues en coupe faites selon les lignes II-II des figures 1a et 1b,
• les figures 3a à 3c représentent des vues similaires aux figures 1a à 1c mais illustrant les étapes de décrochage d'une charge, conformément au procédé selon l'invention, et
• la figure 4 montre une vue de dessus d'un plateau-support de charge reposant sur des moyens d'ancrage d'une station partiellement représentée.

Other characteristics and advantages of the invention will appear more clearly on reading the following description of an embodiment of the invention given solely by way of illustration and not limitation, this description being made in conjunction with the drawings in which :

• FIGS. 1a to 1c represent views in partial section of the thermal treatment installation illustrating the steps for hooking a load in a station in accordance with the method according to the invention,
• FIGS. 2a and 2b represent sectional views taken along lines II-II of FIGS. 1a and 1b,
• FIGS. 3a to 3c represent views similar to FIGS. 1a to 1c but illustrating the steps of detaching a load, in accordance with the method according to the invention, and
• Figure 4 shows a top view of a load support plate resting on anchoring means of a partially shown station.

Referring to Figures 1a to 1c and 2a, 2b, we see a heat treatment installation according to the invention designated by the general reference 1.

This installation 1 comprises a bell furnace 2, i.e. an oven open down inside from which can be introduced, via an opening 4, and by vertical displacement, a load 6 formed by a part or a set of parts to be treated arranged on a support plate 8 (Figure 4). The oven 2 includes a sealed enclosure 10 associated with heating means 12, such as for example resistance ramps electric. Opening 4 can be closed with a plug 14 during processing operations.

In the lower part of enclosure 10, at in the vicinity of the opening 4, studs are provided or three retaining brackets 16 (only two of which are visible in Figures 1a-1c and 2a-2c). These studs 16 protrude radially from the inner wall of the enclosure 10. The studs 16 give the opening 4 a indented outline, circular in the example shown (Figure 2b). These studs 16 are intended for support the support plate 8 provided with the load 6, in particular between the processing operation (s) when the oven is open (Figure 1c). Indeed, when the oven 2 is closed by the plug 14, the support plate 8 is preferably raised above the studs 16 by feet of support 18 integral with the plug, in order to avoid creep studs 16 under the weight of the load 6.

According to another embodiment not shown, these studs 16 can be arranged at another level of the inner wall of the enclosure 10.

The installation also includes means conventional load loading and unloading 6 in and from the oven 2, which can be made by a manipulator robot 20. This robot 20 has an arm 22 which can be moved vertically along a column of guidance, not shown, by lifting means comprising for example a transmission system by chain and cogwheels, driven by a gear motor.

In the illustrated embodiment, the plug 14 rests on the arm 22. Furthermore, in this example, the oven 2 is mounted mobile and can be moved in translation in an X-Y direction from a first position called loading / unloading shown in the figure 1a, towards a second so-called anchoring position shown in Figure 1b. For this purpose, the installation includes a guideway formed by two parallel rails 24 on which can move said oven 2 via of rollers 26. The oven 2 can be moved in translation on this path through means M drive formed for example of a gear motor training in a classic way, in response to means of control, a pinion meshing with a rack (not shown). In the example described here, the oven 2 rests on the rails 24, but it is understood that according to a variant not shown, the oven 2 can be suspended from a support structure, such as a gantry, by through pebbles and one or more tracks guides placed above and / or on the sides of the oven 2.

The installation shown here also includes (Figures 2a to 2c) a cooling tank 28 in which the load 6 is intended to be quenched, this tank 28 comprising autonomous transfer means 30 for the unloading of the load 6 from the oven 2 to the tank 28. These autonomous transfer means 30 include also an arm which can be moved vertically along a guide column, not shown, by means lift of the same type as those described in connection with the lifting means 20 of Figures 1a to 1c.

As seen in Figure 4, the support plate 8 has the shape of a rigid flat honeycomb grid 32 having at its periphery notches 34 the number of four in the example shown. Grid 32 shows thus a substantially complementary contour and dimensions slightly smaller than that of opening 4 so that grid 32 can pass during loading and unloading through the opening 4.

An example of the implementation of the method of attachment and detachment of the method according to the invention.

Load hooking operation

During this first step, we position everything first the arm 22 of the manipulator robot 20 in a low position. We have the support plate 8 and the load 6 on the support feet 18 of the plug 14.

Then, the arm 22 is raised by actuating the means elevators, to bring the load into enclosure 10 of the oven 2. It should be noted that, during this operation, the support plate 8 will have been placed on feet 18 in an angular position such that the notches 34 are aligned with the retaining studs or consoles 16.

The load 6 and the support plate 8 are brought to a level higher than that of the studs 16 constituting the anchoring means. In this position, the charge 6 and the support plate 8 are in the position of loading unloading.

As shown in Figures 1b and 2b, we move then the oven 2, typically from a distance of 100 mm, at using the drive means M from its position loading / unloading (Figures 1a and 2a) up to a so-called anchoring position (Figures 1b and 2b) in which the pads 16 are superimposed on the support plate 8 by coming, in this example, to partially position under this support plate. Then, the lifting means 20 can be lowered (figure 1c) and the overlapping parts of the support plate 8 can come to rest on the pads 16. These studs 16 serve as means for anchoring the load 6 and thus support the support plate 8 and said load 6 which are anchored by their own weight in the oven 2.

Load release operation

The operation to unhook the load 6 and the support plate 8 is carried out simply by repeating the above above in reverse.

Note, however, that in the example described, at the place lifting means 20, we will use the means risers 30 arranged in the cooling tank 28 (Figures 3a to 3c).

We therefore raise the support plate 8 to a level higher than that of the studs 16 to release them (figure 3a), the oven 2 is moved in translation relative to the support plate 8 to a position of loading / unloading similar to that described above, and lower the load 6 as well as the support plate 8 using the lifting means 30 for the take out of the oven 2.

In the embodiment which is described here, the oven 2 moves for the quenching operation above the cooling tank 28, this tank 25 being fixed. The loading and unloading positions are therefore offset. In another embodiment not shown, the bin 28 can be mounted mobile and come position under the oven 2, so that the operations of loading and unloading are carried out in the same position. So we qualify here as position of loading / unloading a position in which can carry out the two operations mentioned above or one of these operations.

It goes without saying that other means can be envisaged to anchor the support plate 8 in enclosure 10. One could for example provide suspend the support plate 8 in said enclosure by positioning the load 6 under the support plate 8, binding to this support plate 8 by appropriate means or again by placing it in a receptacle provided under the support plate 8.

In addition, other modifications may be made to the process and installation according to this invention whose embodiments have just been described without departing from the scope of this invention.

So, for example, it's also possible to move the lifting means 20 and 30 in translation relative to in oven 2 which can be fixed, and provide the anchoring described above. Likewise it is possible to carry out a installation in which an oven movement is combined 2 and lifting means.

In addition, the plug 14 can be omitted so that the load rests directly on arm 22.

In the example described, the processing station 2 is formed by an oven, but it will be understood that this station could be formed by any other type of station such as a drip station. The installation can in addition to having several ovens in the upper position and / or drip stations and in the lower position multiple cooling stations or other elements of a conventional heat treatment installation.

Claims (10)

1. Method for coupling and uncoupling a load associated with support means, in a heat treatment installation, this installation including :

   at least a treatment station including an opening oriented downwards for receiving said load,

   loading and unloading means for the load, which, via said support means, allow the load to be loaded onto and unloaded from anchoring means arranged in the station,

   characterised in that it consists in coupling and uncoupling the load by imparting a relative movement of translation between said station and the loading and unloading means.
2. Method according to claim 1, characterised in that the movement of translation is carried out by said station.
3. Method according to claim 1 or 2, characterised in that it consists, for the coupling, in :

   bringing said load, via the loading and unloading means, opposite the opening of said station,

   raising the load in said station to bring the support means to a higher level than that of the anchoring means,

   moving the station in translation with respect to the support means from a so-called loading/unloading position to a so-called anchoring position,

   lowering the load to make the support means co-operate with the anchoring means to couple the load in the station.
4. Method according to claim 1 to 3, characterised in that it consists, for the uncoupling, in:

   raising the support means to a higher level than that of the anchoring means to release them from said anchoring means,

   moving the station in translation with respect to the support means from said anchoring position to the loading/unloading position, and

   lowering the load using the loading and unloading means to bring said load out of said station.
5. Heat treatment installation for implementing the method according to any of the preceding claims, comprising :

   at least one treatment station including an opening oriented downwards for receiving the load,

   means for loading and unloading the load onto and from anchoring means arranged in the station,

   characterised in that it includes drive means for moving the station in translation with respect to the load, and control means arranged to guide the drive means in order to ensure the movement in translation of the station to carry out coupling and uncoupling operations of said load onto and from said anchoring means.
6. Installation according to claim 5, characterised in that it includes at least one guide path for said station arranged to ensure the movement in translation of said station.
7. Installation according to claim 6, characterised in that said path includes two parallel rails on which said station rests via rollers.
8. Installation according to any one of claims 5 to 7, characterised in that said station is formed by a furnace.
9. Installation according to claim 8, characterised in that said furnace includes a chamber wherein studs or consoles forming said anchoring means are arranged.
10. Installation according to claim 8, characterised in that said studs project radially from a lower wall of the chamber.

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