WO1989011777A1

WO1989011777A1 - Machine for treating objects with a treating liquid

Info

Publication number: WO1989011777A1
Application number: PCT/EP1989/000436
Authority: WO
Inventors: Rainer Haas
Original assignee: Hans Höllmüller Maschinenbau GmbH & Co
Priority date: 1988-05-24
Filing date: 1989-04-21
Publication date: 1989-11-30
Also published as: ES2014129A6; DE3817542A1

Abstract

A machine for treating objects (25) with a treating liquid, in particular a machine for etching three-dimensional objects (25), comprises a wheel-shaped transport frame (21) to which the objects (25) are secured and which moves through the machine with a kind of rolling movement past one or a plurality of blast connections (15). The rolling movement can take place with or without slip. In each case, it is composed of a linear movement of essentially constant speed and a superimposed rotational movement about the axis of said transport frame.

Description

Machine for treating objects with a treatment liquid

description

5

The invention relates to a machine for treating objects with a treatment liquid

a) a housing;

b) a transport device which continuously guides the objects through the housing;

c) at least one nozzle assembly, to which the objects are introduced before * and from which the objects are sprayed with treatment liquid.

Known machines of this type, as described, for example, in DE-PS 28 51 510, are preferably used in the production of printed circuit boards for electrical circuits. They are used in particular for development and etching, as well as the various rinsing processes associated therewith. The treated objects are to be understood as essentially "two-dimensional"structures; This means that the thickness of these printed circuit boards is essentially negligible compared to the "flat" dimensions. Printed circuit boards of this type can therefore be guided through a relatively simple roller conveyor essentially in a horizontal position under a nozzle assembly or between two nozzle assemblies. There are no particular problems with the holding of the individual objects and / or with a "shadow formation". “Shadow formation” is understood to mean that, due to the third dimension of the objects to be treated, certain zones on these are no longer reached by the spray pattern which is generated by the nozzle sticks. However, efforts have recently been made to provide three-dimensional structures with conductive patterns in a similar manner, in which this has hitherto only been the case for "flat" printed circuit boards. These three-dimensional structures cannot simply be placed on a roller conveyor system; in addition, the problem of "shadow formation" is grave for them.

The object of the present invention is to design a machine of the type mentioned in the introduction in such a way that it can also be used to treat cre-dimensional objects.

This object is achieved according to the invention in that the transport device comprises a wheel-shaped support frame to which at least one object is fastened and which is passed through the housing in a kind of rolling motion while rotating about its own axis.

In a machine according to the invention, the three-dimensional objects to be treated are therefore no longer placed "freely" on a transport system and passively conveyed through the machine; rather, they are fastened (for example clamped) to a wheel-shaped support frame, which is then guided in a defined manner through the machine and past the nozzle assemblies: in a kind of rolling movement, the support frame receives both a linear movement which passes through the support frame the machine passes through it, as well as a rotary movement about its own axis, by means of which the relative position of the objects attached to the support frame to the nozzle sticks and thus to the spray patterns of the treatment liquid is changed. This type of transport movement thus simultaneously solves both the transport and the shadow problem, which occurs for the first time in the treatment of three-dimensional objects. When the wheel-supporting frame is arranged vertically and rise with its circumferential surface on a base, the weight of the ^'supporting frame is, as the weight of the attached thereto the article from the substrate taken auf¬. A special further storage of the support frame is no longer necessary. The type of transport of such a supporting frame largely corresponds to that of a wheel.

The wheel-shaped support frame can be guided in a slot in its upper region. The slot prevents the support frame from tipping out of its vertical arrangement.

In particular, the wheel-shaped support frame can stand on the shoulders of two parallel longitudinal members, between which a slot remains. The slot creates, as will be explained later, on the one hand space for further devices which are intended to act on the supporting frame; on the other hand, it facilitates the dripping of treatment liquid from the support frame and the treated object into a sump provided in the lower area of the machine.

The rolling movement of the support frame can be essentially slip-free over at least part of the movement path. Then the circumferential speed and the linear movement speed of the support frame essentially match. This type of movement is mainly selected in those areas of the machine in which the objects are not treated.

Preferably. a rotational acceleration device is provided which, at least in the zones in which the nozzle assemblies are active, sets the wheel-shaped support frame at a rotational speed which is greater than in the case of non-slip rolling. With slip-free rolling, the conditions could be such that the support frame within the The area of action of a nozzle assembly does not even cover a complete revolution, so that the risk of shadow formation is not completely eliminated. If the support frame is now set at a higher rotational speed in the treatment zones of the machine than is necessary to achieve the linear movement, it can be ensured that the support frame in the area of each nozzle stock performs the required number of full rotations, one of which Shadow formation no longer occurs with certainty.

The rotary acceleration device can comprise an endless belt which is moved at a speed which is higher than the linear speed of the wheel-shaped support frame and which bears against the lateral surface of the wheel-shaped support frame.

In this case, it is appropriate that the rotary acceleration device is arranged in the slot between the two longitudinal beams.

In principle, it would be conceivable to let the wheel-shaped support frame roll more or less freely through the machine when the corresponding base is inclined. In this way, a separate drive would be unnecessary.

However, this configuration makes it difficult to maintain a constant movement speed even in those areas in which the linear movement of the support frame is opposed by resistances; Difficulties would also arise in the case where one

Rotary acceleration device is to be used. It is therefore generally preferred if a drive device is provided which specifies the linear speed of the wheel-shaped support frame.

The drive device can comprise, for example, an endless belt or an endless chain, on which at regular intervals Spacing drivers for the wheel-shaped support frame are attached. The drivers then move at a speed which corresponds to the desired linear movement of the wheel-shaped support frame.

The wheel-shaped support frames are positively guided when the drivers engage in pairs on a wheel-shaped support frame.

Since the wheel-shaped support frames perform a rolling movement, the drive device is advantageously designed so that the drivers are rollers in order to avoid unnecessary frictional forces.

In known machines of the type mentioned at the outset, which work with essentially two-dimensional objects, the carry-over of treatment liquid into another zone is generally prevented by pairs of nip rollers through which the objects are passed. This arrangement is of course no longer possible with three-dimensional objects. According to the invention, therefore, in order to prevent the spread of treatment liquid as far as possible, each zone in which a nozzle assembly is arranged is delimited on both sides by panels which can be passed through by the wheel-shaped support frame.

In one configuration, the diaphragms are rigid and can be adjusted in the direction of the axis of rotation of the wheel-shaped support frame in such a way that a slot remaining between them can be adapted to the width of the wheel-shaped support frame or the workpiece.

Alternatively, the screens can be elastic curtains, which only open when a wheel-shaped support frame is approached and bent out. An embodiment of the invention is explained below with reference to the drawing; the single figure shows schematically a vertical longitudinal section through a machine for etching three-dimensional circuit boards.

The embodiment shown in the drawing of a machine for etching three-dimensional circuit boards has a modular structure; however, this is not a necessary feature of the present invention. The machine comprises an inlet zone 2, an etching zone 3, a first rinsing zone 4, a second, double rinsing zone 5 and an outlet zone 6 in an erroneous housing 1.

The etching zone 3, the first rinsing zone 4, the second rinsing zone 5 and the outlet zone 6 include sumps 7, 8, 9 and 10 in the respectively assigned lower part of the machine, in which the respective treatment liquid (etchant, water or the like) can collect.

Above the sumps 7 to 10 there are nozzle assemblies 11, 12, 13, 14 in the various zones of the machine, through which the workpieces to be etched pass in a manner to be described, which are pumped by means of pumps (not shown) via lines (also not shown) are supplied with the respective processing liquid and from which the passing workpieces transported to the treatment f ü ^'are sprayed lIQUID. The detailed design of the nozzle assemblies 11 to 14 and the associated supply and circulation systems are not the subject of the present invention, unless explicitly referred to in the following. To this extent, all known configurations of the nozzle assemblies, in particular oscillating nozzle assemblies of all types, can be used; Known designs, in particular fan nozzles, ball joint nozzles or telescopic nozzles, which can also be extended from the nozzle block, can also be used for the nozzles 15 fastened to the nozzle blocks. A special feature of the nozzle assemblies 11 to 14 in the illustrated The th embodiment is its vertical orientation, whereas in the case of the etching machines for "two-dimensional" printed circuit boards which have been in use up to now, a horizontal orientation of the nozzle sticks has been used.

The nozzle assemblies 11 to 14 are each provided twice, ie in each zone 3, 4 and 5 the nozzle assemblies 11, 12, 13, 14 are once behind the drawing plane (this is the nozzle assembly shown in each case) and once in front of the Zei¬ plane, so that the workpiece passing between them can be sprayed from both sides.

In the upper area of the housing 1 of the machine, two longitudinal members 16 are provided, between which a slot 17 remains. The side members run over the entire longitudinal dimension of the machine. Correspondingly, about half the height of the machine, i.e. Below the nozzle blocks 11 to 14 and above the sumps 7 to 10, two parallel longitudinal beams 18 are provided, between which a slot 19 also remains. The longitudinal members 18 are formed on their mutually facing inner sides with a step 20, so that a radför-shaped clamping frame 21 can rest and roll on these steps 20 from above.

The wheel-shaped support frame 21 serves to convey the individual workpieces 25 which are to be etched in the machine through the various zones. For this purpose, it comprises an annular rim 22, the width of which is somewhat smaller than the width of the slot 17 between the two longitudinal beams 16 and somewhat smaller than the width of the slot 19 between the two longitudinal beams 18 in the region above the step 20. In this way, the wheel-shaped support frame 21 can, as already mentioned, with its upper one

Extend circumferential area between the two longitudinal beams 16 and guided with its lower peripheral area on the shoulder Roll 20 of the two longitudinal beams 18.

On the annular rim 22 of the wheel-shaped support frame

21, two parallel rods 23 are fastened, on which in turn two displaceable clamping jaws running transversely thereto

24 are clamped. The workpiece 25 to be treated is held between the clamping jaws 24 on its way through the machine.

The wheel-shaped support frame 21 is conveyed in the longitudinal direction through the various zones 2, 3, 4, 5 and 6 of the machine by a drive device, which bears the overall reference number 26. The drive device 26 comprises an endless chain or a flexible endless belt 27 which extends between two deflection rollers 28, 29, one of which is driven, on the two ends of the machine. On the endless chain 27, roller-shaped carriers 30 are fastened at regular intervals, each of which is assigned in pairs to a wheel-shaped support frame 21. The assignment takes place in such a way that the roller-shaped drivers 30 belonging to a pair in the lower run of the endless chain 27 rest symmetrically on opposite sides of a vertical diameter on the outer circumferential surface of the annular rim 22 of the wheel-shaped support frame 21. If the endless chain 27 thus moves in the direction indicated by arrows in the drawing, that is to say if the lower run of the endless chain 27 moves from left to right in the drawing, the wheel-shaped support frame 21, which is between the two roller-shaped carriers 30 one

Couple lies on this move. The support frame 21 rolls on the steps 20 of the side members 18, also in the sense indicated by an arrow, and moves like a wheel through the entire machine from left to right. The roller-shaped drivers 30 of the drive device 26 are also set in rotation. The rotational movement of the wheel-shaped support frame 21 resulting from the rolling process has the result that the workpiece 25 clamped in it is guided past the various nozzle sticks 11, 12, 13, 14 at the most varied angles to the spray patterns, so that a "shadow formation ", that is, the formation of zones on the workpiece 25 that cannot be reached by the treatment liquid is avoided. This is extremely important for three-dimensional workpieces 25.

In the illustrated embodiment, the wheel-shaped support frame 21 rolls in the inlet zone 2 and in the outlet zone 6 essentially without slip on the steps 20 of the longitudinal beams 18. In principle, this type of forward movement could be maintained over the entire longitudinal dimension of the machine. However, since with this mode of movement within the effective ranges of the nozzle assemblies 11, 12, 13 and 14 only a few, in some cases no complete rotation of the wheel-shaped support frame 21 would take place and the risk of shadows would not yet be completely eliminated, Zones 3, 4 and 5 provided a rotational acceleration device. Overall, this is identified by reference number 31.

The rotational acceleration device 31 is arranged in the slot 19 between the two longitudinal beams 18. It comprises an endless belt 32 which extends between the deflection rollers 33 and 34, one of which is driven. The direction of movement of the endless belt 32 of the Drehbeschleu- ^• nigungseinrichtung 31 is marked in the drawing by arrows. The upper run of the endless belt 32 moves from right to left in the drawing and lies against the outer surface of the annular rim 22 of the wheel-shaped jag frame 21. The movement of the endless belt 32 is converted into a rotary movement of the wheel-shaped support frame 21 by an appropriate design of the frictional relationships The speed of movement of the endless belt 32 is now many times higher than the speed of movement of the endless chain 27, which is part of the drive device 26. The result of this is that the wheel-shaped support frame 21 in the area in which it rests on the endless belt 32 is set to a rotational speed which is several times higher than in order to achieve the linear speed predetermined by the drive device 26. Between the deflection rollers 33 and 34, the wheel-shaped support frame 21 thus rotates so quickly with respect to the steps 20 on the side members 18 that it can perform several full rotations in the area of action of the nozzle assemblies 11, 12, 13 and 14. This ensures that all angles on the workpiece 25, which is conveyed through the machine by the support frame 21, are actually also reached by the treatment liquid in the treatment zones 3, 4 and 5.

Zones 3, 4, 5 of the machine, in which workpieces 25 are sprayed with a treatment liquid, are delimited on both sides by a plurality of screens 35. These diaphragms 36, which can be adjusted in a direction perpendicular to the plane of the drawing, leave a gap in the middle which just allows passage of the wheel-shaped support frame 21 together with the workpiece 25. In this way, carryover of treatment liquid into the neighboring zone is largely avoided.

Instead of rigid, adjustable diaphragms, in certain cases it is also possible to use curtain-like, elastic diaphragms which open automatically when the wheel-shaped support frame 21 approaches and close again behind it.

The machine described is operated using a number of identical wheel-shaped support frames 21 in the following manner: The workpieces 25 to be treated are clamped in a treatment station upstream of the machine between the clamping jaws 24 of the wheel-shaped support frames 21. The support frames 21 "loaded" in this way are placed one after the other in the inlet zone 2 on the shoulders 20 of the side members 18. The upper circumferential area of the supporting frame 21 thus placed is gripped by two roller-shaped carriers 30 of the transport device 26; the wheel-shaped support frame 21 begins to roll, moving longitudinally through the machine. As soon as the respective support frame 21 has reached the area in which the endless belt 32 of the rotary acceleration device 31 runs, an additional rotary movement is superimposed on its pure rolling movement. In the manner of a "spinning wheel", but with the linear speed of the transport device 26, the wheel-shaped support frame 21 then crosses the treatment zones 3, 4 and 5, in which the clamped workpiece 25 from both sides with the corresponding treatment liquids from the Nozzle sticks 11, 12, 13 and 14 is sprayed.

Then the respective support frame 21 is delivered to the outlet zone 20, where in turn a pure rolling movement takes place without slippage. The support frames 21 are removed at the end of the outlet zone with the finished workpieces 25. If necessary, the support frame 21 with the clamped workpiece can be fed to a subsequent machine or the workpiece 25 is removed from the support frame 21.

The arrangement is such that in normal operation a plurality of support frames 21 are simultaneously in different zones on the way through the machine. For reasons of clarity, only one of these support frames 21 is shown in the drawing.

Claims

Claims 05

1. Machine for treating objects with a treatment liquid, with

a) a housing;

10. b) a transport device which continuously guides the objects through the housing;

c) at least one nozzle assembly, on which the objects are brought in and from which the objects are sprayed with treatment liquid,

characterized in that the transport device comprises a wheel-shaped support frame (21) to which at least 20 an object (25) is fastened and which is passed through the housing (1) in a kind of rolling motion while rotating about its own axis.

2. Machine according to claim 1, characterized in that 25 of the wheel-shaped support frame (21) is arranged vertically and with its outer surface on a base (20) stands up.

3. Machine according to claim 2, characterized in that 30 of the wheel-shaped support frame (21) is guided in its upper region in a slot (17).

4. Machine according to claim 2, characterized in that the wheel-shaped support frame (21) on shoulders (20)

35 two parallel longitudinal members (18) stands between which a slot (19) remains. 5. Machine according to one of the preceding claims, characterized in that the rolling movement of the support frame (21) is essentially slip-free at least over part of the movement path.

6. Machine according to one of the preceding claims, da¬ characterized in that a rotational acceleration device (31) is provided, which the wheel-shaped support frame (21) at least in the zones in which the nozzle stock (11, 12, 13, 14) are effective, set at a rotational speed which is greater than in the case of non-slip rolling.

7. Machine according to claim 6, characterized in that the rotary acceleration device (31) is an endless belt

(32), which is moved at a speed that is higher than the linear speed of the wheel-shaped support frame (21), and rests against the outer surface of the wheel-shaped support frame (21).

8. Machine according to claim 6 when referring back to claim 4, characterized in that the rotational acceleration device (31) is arranged in the slot (19) between the two longitudinal beams (18).

9. Machine according to one of the preceding claims, da¬ characterized in that a drive device (26) is provided, which specifies the linear speed of the rad-shaped support frame (21).

10. Machine according to claim 9, characterized in that the drive device (26) is an endless belt or

Endless chain (27) on which at regular intervals. Carriers (30) for the wheel-shaped support frame (21) are fastened.

11. Machine according to claim 10, characterized in that the drivers (30) each engage in pairs on a wheel-shaped support frame (21).

12. Machine according to claim 10 or 11, characterized gekenπzeich- 05 net that the drivers (30) are rollers.

13. Machine according to one of the preceding claims, da¬ characterized in that each zone in which a

Nozzle block (11, 12, 13, 14) is arranged, is delimited on both sides by 10 diaphragms (35) which can be passed through by the wheel-shaped support frame (21).

14. Machine according to claim 13, characterized in that the diaphragms (35) rigid and in the direction of the rotary

15 axis of the wheel-shaped support frame (21) are adjustable so that a slot between them the width of the wheel-shaped support frame (21) or the workpiece (25) is adjustable.

20 15. Machine according to claim 13, characterized in that the panels (35) are elastic curtains.