Apparatus and method for controlling the temperature of workpieces

Abstract

An apparatus for controlling the temperature of workpieces, in particular of vehicle bodies, has a temperature-control tunnel, a traction chamber and an intermediate floor which is arranged between the temperature-control tunnel and the traction chamber and which has a connection passage. The apparatus includes a conveying device for conveying the workpieces in the temperature-control tunnel, wherein the conveying device has at least one conveying carriage with a running gear and has a workpiece carrier for holding the workpieces of which the temperature is to be controlled. The running gear is arranged in the traction chamber and is connected by a connecting device, which projects through the connection passage of the intermediate floor, to the workpiece carrier arranged in the temperature-control tunnel. To control the temperature of the traction chamber and thus adequately protect the running gear against heat or cold, the intermediate floor is equipped at least in regions with an active cooling and/or heating means.

Claims

1. An apparatus for controlling the temperature of workpieces, comprising: a) a temperature control tunnel, b) a tunnel tube, c) an intermediate floor, which separates the temperature control tunnel from the tunnel tube and has a connecting passage, and d) a conveying device for conveying the workpieces in the temperature control tunnel, e) wherein the conveying device has at least one trolley having a running gear and a workpiece carrier for receiving the workpieces to be temperature-controlled, wherein the running gear is arranged in the tunnel tube and, with a connecting device which projects through the connecting passage of the intermediate floor, is connected to the workpiece carrier arranged in the temperature control tunnel, and further wherein f) the intermediate floor, at least in some regions, is equipped with an active cooling and/or heating system in order to control a temperature of the tunnel tube, wherein the active cooling and/or heating system comprises a cavity, which is arranged in the intermediate floor and is designed to be flowed through with a cooling or heating medium.

2. The apparatus for controlling the temperature of workpieces, as claimed in claim 1, wherein the active cooling and/or heating system comprises a plurality of cavities, which are arranged in the intermediate floor.

3. The apparatus for controlling the temperature of workpieces, as claimed in claim 2, wherein the plurality of cavities have different flow cross sections.

4. The apparatus for controlling the temperature of workpieces, as claimed in claim 1, wherein the active cooling and/or heating system comprises a Peltier element or a heating element.

5. The apparatus for controlling the temperature of workpieces, as claimed in claim 1, wherein the intermediate floor has a collecting region in which condensate from air of the temperature control tunnel can collect.

6. The apparatus for controlling the temperature of workpieces, as claimed in claim 1, wherein the intermediate floor has an insulating layer.

7. The apparatus for controlling the temperature of workpieces, as claimed in claim 1, wherein the active cooling and/or heating system is designed to control the temperature to differing extent along a direction of conveyance of the conveying device.

8. The apparatus for controlling the temperature of workpieces, as claimed in claim 1, wherein the active cooling and/or heating system is dimensioned such that temperatures of heat-sensitive components of the running gear in the tunnel tube can be limited to a range of maximally 60° C. or minimally 0° C.

9. The apparatus for controlling the temperature of workpieces, as claimed in claim 8, wherein the active cooling and/or heating system is dimensioned such that, at the provided temperatures of the dryer tunnel, the temperatures of heat-sensitive components of the running gear in the tunnel tube can be limited to a range of maximally 40° C. or minimally 20° C.

10. The apparatus for controlling the temperature of workpieces, as claimed in claim 5, wherein the collecting region is a collecting channel.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Illustrative embodiments of the invention are explained in greater detail below with reference to the drawings, in which:

(2) FIG. 1 shows a perspective view of an apparatus according to the invention for controlling the temperature of workpieces, comprising a temperature control tunnel and a tunnel tube which is separated from the temperature control tunnel by an intermediate floor;

(3) FIG. 2 shows a cross section through the apparatus from FIG. 1;

(4) FIG. 3 shows an enlarged detail from the cross section according to FIG. 2, which more closely shows the region of the intermediate floor around a connecting passage;

(5) FIG. 4 shows an enlarged detail, in accordance with FIG. 3, of an alternative illustrative embodiment;

(6) FIG. 5 shows a corresponding detail according to FIG. 3 in accordance with a further illustrative embodiment.

DESCRIPTION OF PREFERRED ILLUSTRATIVE EMBODIMENTS

(7) FIG. 1 shows a temperature control apparatus, denoted by 10, which is here configured as a dryer. The temperature control apparatus 10 has a temperature control tunnel 12, in which a workpiece 14 to be temperature-controlled, here a vehicle body, is arranged.

(8) The workpiece 14 is located on a workpiece carrier 16, which, above an intermediate floor 18, is moved through the temperature control tunnel 12.

(9) To this end, a conveying device 20 comprising a monorail 22, which is arranged beneath the intermediate floor 18 and along which a running gear 24 moves in a tunnel tube 26, is provided.

(10) For this, the running gear 24 is connected to the workpiece carrier 16 via a connecting device 28, which can be seen more closely from FIGS. 2 to 5. The connecting device 28 passes for this purpose through a connecting passage 30 in the intermediate floor 18, wherein as an additional dirt barrier over the connecting passage 30 there is arranged a shutter 31 (cf. FIGS. 3 to 5), the slats of which are pushed aside by the connecting device 28.

(11) In addition, the here shown temperature control apparatus 10, as can be seen from FIG. 2, has lateral supply air ducts 32, which are delimited from the temperature control tunnel 12 by a partition wall 34. The partition wall 34 has outlet openings 36, out of which passes hot air for controlling the temperature of, in the present case in particular for drying, the workpiece 14.

(12) As can be seen from FIG. 2, and in particular from the enlargement details of FIGS. 3 to 5, the intermediate floor 18 has primarily in the inner region, above the tunnel tube of the conveying device 20, a floor portion 38 of roughly wedge-shaped cross section.

(13) According to the invention, it is now provided that the floor portion 38 has at least one cavity 40, in which cooling or heating medium flows. For this, the floor portion 38 is provided with ports (not shown), which allow the cavity 40 to be fed a cooling medium or a heating medium in order, in the here shown example, to flow lengthwise through the floor portion 38 along the direction of conveyance of the conveying device 20.

(14) In this way, in the tunnel tube 26, above all the heat-sensitive parts of the running gear 24, such as a drive wheel or pressure rollers, are protected from excessively high temperatures. In particular, maximum temperatures of 60° C. are not here exceeded.

(15) As can further be seen from FIG. 3, the top side of the floor portion 38 is provided with a slope which, starting from the connecting passage 30, slopes down toward the outside. Moreover, the floor portion 38, in relation to an adjacent portion 42 of the intermediate floor 18, is offset with a stagger, in particular with a stagger of less than 5 cm, in the downward direction. As a result, at the outer end of the floor portion 38 is formed a collecting region 39, in which condensate that, due to the active cooling, condenses out from the air of the temperature control tunnel 12 on the top side of the floor portion 38 can collect.

(16) For the evacuation of the condensate, along the direction of conveyance in the here shown example, drains (not represented) are provided.

(17) FIG. 3 shows an illustrative embodiment in which the floor portion 38 of the intermediate floor 18 is not provided with a slope, but instead bears an insulating layer 44. The insulating layer 44 is here formed of such a material and is dimensioned such that, at the anticipated temperatures which prevail in the temperature control tunnel 12 during the operation of the temperature control apparatus 10 and at the corresponding air humidity values, the dew point of the respective condensate liquid lies inside the floor portion 38 and not on the surface thereof.

(18) Finally, FIG. 5 shows an illustrative embodiment in which the floor portion 38 is designed as a simple supporting plate with the applied insulating layer 44. Furthermore, instead of the cavities 40, Peltier elements 50 are provided, which, electrically actuated, generate a cooling output. The Peltier elements 50 too thereby provide, in the region of the intermediate floor portion 38, an actively cooled structural element as heat shielding from the temperatures of the temperature control tunnel 12. For the design of the floor portion 38, the use of the Peltier elements 50 here allows substantially only the statics of the supporting plate to be taken into account. Cavities and ports for appropriate cooling or heating mediums are not necessary here.

(19) The Peltier elements 50 can also be provided only as supplementary cooling elements in individual regions of the temperature control tunnel 12 in order in this way, for instance, along the direction of conveyance of the temperature control tunnel 12, to provide different cooling and heating outputs, depending on the temperature prevailing in the appropriate region of the temperature control tunnel.