Device, and method for treating workpieces

Abstract

The invention relates to a device (1) and a method for treating workpieces, in particular for surface-treating workpieces. The device contains a process chamber (PK1, PK2, PK3), into which a workpiece to be treated can be introduced and which can be filled with a solvent (LM); a closure unit (VE) for opening and closing the process chamber (PK1, PK2, PK3); and a vacuum pump (VP) which can be brought into fluidic connection with the process chamber in order to evacuate the process chamber (PK1, PK2, PK3). A first valve (V1) is arranged in the fluidic connection between the process chamber (PK1, PK2, PK3) and the vacuum pump (VP).

Description

[0001] Device and method for treating workpieces

[0002] The invention relates to a device and a method for treating workpieces, in particular for the surface treatment of workpieces with a delicate or porous structure, including capillary structures, such as the removal of loose particles during the post-treatment of additively manufactured workpieces and / or the passivation of the workpiece surface. Such treatment of workpieces is particularly challenging when the workpieces have blind holes, especially capillary blind holes. The treatment of workpieces specifically involves cleaning or passivating the surfaces of such workpieces.

[0003] Devices and methods for cleaning workpieces are known, for example, from EP1338680A1 or from DE102017126329A1.

[0004] EP1338690A1 describes a method for cleaning a workpiece in which a solvent mixture of isoparaffins is used in a first cleaning stage, followed by deionized water with a surfactant in a second cleaning stage. This is followed by a rinsing step with deionized water and a final drying step. A disadvantage of this method is the use of an organic solvent.

[0005] DE102017126329A1 describes a method for cleaning a workpiece in which the workpiece is exposed to a cleaning fluid in a cleaning chamber. This fluid is initially subjected to overpressure and then underpressure, or initially to underpressure and then overpressure. The alternating overpressure and underpressure is intended to induce cavitation effects in the cleaning fluid, thereby dislodging contaminants adhering to the workpiece by fluid mechanics. Known devices for treating workpieces include a process chamber into which a workpiece to be treated can be placed and which can be at least partially filled with, or is filled with, a treatment fluid (BF). They also include a vacuum pump (VP) which can be connected to the process chamber to evacuate it.

[0006] Other known methods for treating workpieces use an interplay of pressure drops and pressure increases of the treatment fluid in the process chamber. One such method is described in WO2022 / 106886A1.

[0007] When treating the workpiece with treatment fluid and vacuum, the aim is to bring the treatment fluid to the entire surface of the workpiece and to expose the entire surface of the workpiece to pressure fluctuations (alternating build-up and release of the vacuum).

[0008] When evacuating a process chamber containing the workpiece surrounded by treatment fluid, foam, droplets, or splashes of treatment fluid can form during the evacuation of the free volume within the chamber. These droplets or splashes could enter the fluid connection between the vacuum pump and the process chamber. If treatment fluid enters this connection, the vapor pressure of the treatment fluid makes evacuation more difficult, thus slowing down and impairing the process.

[0009] The invention is based on the objective of providing a device and a method for treating a workpiece, in particular for surface treatment of the workpiece, whereby fluid-mechanical effects and / or solvent effects are used in the treatment of the workpiece with simple mechanical means.

[0010] To solve this problem, the invention provides a device according to claims 1 to 35 and a method according to claims 36 to 53 for treating workpieces.

[0011] According to a first aspect, the invention provides a device (1) for treating workpieces, in particular for surface treatment of workpieces, wherein the device comprises: a process chamber (PK1, PK2, PK3) into which a workpiece to be treated can be placed and which can be at least partially filled or is filled with at least a solvent (LM); a closure unit (VE) for opening and closing the process chamber (PK1, PK2, PK3); and a vacuum pump (VP) which can be brought into fluid communication with the process chamber (PK1, PK2, PK3) for evacuating the process chamber; characterized in that a first valve (V1) or a vacuum pump valve is arranged in the fluid connection between the process chamber (PK1, PK2, PK3) and the vacuum pump (VP).

[0012] The process chamber can be filled with at least one solvent.

[0013] The process chamber can also be filled with various treatment fluids.

[0014] For successive treatment steps, the process chamber can be filled with the respective treatment fluid required for each treatment step, and at the end of each treatment step, the respective treatment fluid is removed from the process chamber.

[0015] During a single treatment step, several different treatment fluids can be added simultaneously and as a mixture to the respective process chamber.

[0016] The respective treatment steps can be carried out in the respective process chamber either at atmospheric pressure or under vacuum with an active vacuum pump and the first valve or vacuum pump valve open. Preferably, the device includes

[0017] - a process chamber (PK1, PK2, PK3) into which a workpiece (W) to be treated can be placed and which can be at least partially filled or is filled with a treatment fluid (BF); and

[0018] - a vacuum pump (VP) which can be brought into fluid communication with the process chamber (PK1 , PK2 , PK3) for evacuating the process chamber, characterized in that a branching area (VB) is arranged in the fluid connection between the vacuum pump (VP) and the process chamber (PK1 , PK2 , PK3), into which a first channel section (K1), a second channel section (K2) and a third channel section (K3) open; wherein

[0019] - the first channel section (K1 ) is in fluid connection with the process chamber (PK1 , PK2, PK3) or can be brought into fluid connection and has a first channel constriction (KE1 );

[0020] - the second channel section (K2) can be brought into fluid contact with the vacuum pump (VP); and

[0021] - the third channel section (K3) can be brought into fluid contact with a purge gas source (AT).

[0022] Preferably, a basin-like depression (BS) is provided in the branching area (VB) between the channel constriction (KE1) and the second channel section (K2), the fluid outlet of which is formed by the channel constriction (KE1) or for which the channel constriction (KE1) forms a fluid outlet.

[0023] Thus, treatment fluid BF can accumulate in the basin-like depression BS of the first channel constriction KE1, which, when the process chamber PK1, PK2, PK3 is evacuated through the first channel constriction KE1 into the

[0024] Branching area VB can be reached (as described on page 1, last paragraph and page 2, first paragraph)

[0025] Preferably, a vacuum pump valve (VV2) is arranged in the second channel section (K2), with which the fluid connection between the

[0026] The branching section (VB) and the vacuum pump (VP) can be opened or closed. Thus, the vacuum pump valve can be opened to begin a step of evacuating the process chamber and closed to end that step. During evacuation, in addition to air, vapor from the treatment fluid and treatment fluid not contained by the channel constriction, particularly water vapor or liquid water, can pass through the channel constriction. This can occur due to bursting vapor bubbles, resulting in liquid splashes and / or liquid foam. Due to gravity, a large portion of the transported treatment fluid can collect in the basin-like depression to avoid reaching the vacuum pump.

[0027] Preferably, an atmospheric valve (AV) is arranged in the third channel section, with which the fluid connection between the branching area (VB) and the purge gas source (AT) can be established or interrupted.

[0028] The vacuum pump valve can then be closed to complete the evacuation of the process chamber. The atmospheric valve can now be opened ("breaking the vacuum") to begin the process of rinsing, or returning, or blowing back the treatment fluid collected in the basin-like depression into the process chamber using a purge gas, e.g., atmospheric air and / or an inert gas. The valve can then be closed to complete the rinsing step, i.e., returning the treatment fluid to the process chamber(s).

[0029] Preferably, the channel constriction (KE1) on the side of the branching region (VB) has a widening region (AB) which widens from a region with a minimum flow cross-section to a region with a maximum flow cross-section. This widening can be funnel-shaped. Preferably, the widening region (AB) forms part of the basin-like depression (BS) or forms a transition from the region with a minimum flow cross-section to the basin-like depression (BS).

[0030] This allows for the most complete possible rinsing, recirculation, or blowing of the treatment fluid accumulated in the basin-like depression by means of rinsing gas (atmospheric air and / or inert gas) penetrating the branching area, if necessary even against gravity and towards the area with minimal flow cross-section (fluid outlet).

[0031] Preferably, the widening area (AB) has a funnel-shaped form or is designed in a funnel shape.

[0032] The inner surface of the widening area (AB) can have a) a conical or b) a concave or c) a convex shape.

[0033] The expansion area can have a rotationally symmetrical inner surface formed by a generating element rotating about an axis (geometry axis of the expansion area AB or generating axis of rotation) which is a) rectilinear, b) concavely curved, or c) convexly curved, resulting in a) conical shape, b) tulip shape, or c) chanterelle shape.

[0034] The expansion area can also have a shape that deviates from rotational symmetry.

[0035] Preferably the first channel constriction (KE1 ) is arranged at a funnel outlet area or at the tapered end of the funnel-shaped form, wherein the funnel-shaped form opens into the first channel section (K1 ) with its tapered end.

[0036] Preferably a first vacuum valve (VV1) is arranged at the funnel outlet area or at the tapered end of the funnel-shaped form.

[0037] Preferably, a second channel constriction KE2 is arranged at a funnel inlet area or at a flared end of the funnel-shaped form, wherein the funnel-shaped form opens into the second channel section (K2) at its flared end.

[0038] Preferably a second vacuum valve (W2) is arranged at the funnel inlet area or at the widened end of the funnel-shaped form.

[0039] Preferably an atmosphere valve (AV) is arranged at a funnel inlet area or at a flared end of the funnel-shaped form, wherein the funnel-shaped form opens into the third channel section (K3) at its flared end.

[0040] Preferably, the third channel section (K3) opens into the funnel-shaped chamber of the branching region (VB) along a channel opening direction of the channel section (K3), which is offset with respect to the round or rounded inner shape of the funnel-shaped chamber, in particular with respect to the rotational symmetry axis of the funnel-shaped chamber, and has a tangential component as well as a radial component with respect to the round or rounded inner shape.

[0041] Preferably, in the channel outlet direction, the tangential component is larger than the radial component, with the radial component being particularly zero.

[0042] Preferably, the channel outlet direction of the channel section (K3) is inclined downwards with respect to the funnel-shaped chamber towards the funnel outlet or towards the tapered end of the funnel, or has an axial component with respect to the rounded inner shape, which is directed towards the first channel section (K1).

[0043] When the branching section VB is flushed with air or an inert gas, less turbulence is generated, thus preventing splashing and / or foaming of the treatment fluid BF when emptying the connection section VB. The flushing gas flowing from the flushing gas source AT into the funnel-shaped chamber through the third channel section K3 expands and flows along the inner walls of the funnel-shaped chamber to blow the droplets of condensed treatment fluid adhering to the inner walls towards the funnel outlet or the tapered end of the funnel-shaped chamber.

[0044] Preferably, the second channel section (K2), which can be brought into fluid contact with the vacuum pump (VP), has a further or second channel constriction (KE2).

[0045] The second channel constriction, similar to the first, can capture a further portion of the treatment fluid carried during evacuation, which then flows, due to gravity, into a second basin-like depression associated with this second channel constriction. Through the action of gravity, a portion of the treatment fluid transported during evacuation that does not evaporate can collect in this second basin-like depression, preventing it from reaching the vacuum pump.

[0046] Preferably, a further or second vacuum pump valve (W2) is arranged in the second channel section (K2) between the branching area (VB) and the further or second channel constriction (KE2).

[0047] Preferably, a further or third vacuum pump valve (VV3) is arranged in the second channel section (K2) between the further or second channel constriction (KE2) and the vacuum pump (VP).

[0048] Preferably, at least a part of the inner wall of the branching area (VB) is thermally connected to a coolant.

[0049] Even more treatment fluid can condense on the coolable part of the inner wall.

[0050] According to a second aspect, a vacuum tank (VT) is arranged in the fluid connection between the first valve (V1) and the vacuum pump (VP). Preferably, the vacuum tank volume (VTV) of the vacuum tank (VT) is a multiple of the process chamber volume (PKV) of the process chamber (PK1, PK2, PK3).

[0051] Advantageously, the ratio VTV / PKV of vacuum tank volume (VTV) of the vacuum tank (VT) to process chamber volume (PKV) of the process chamber (PK1 , PK2, PK3) lies within a range of 5 to 200 (5 < VTV / PKV < 200) and preferably within a range of 10 to 200 (10 < VTV / PKV < 200).

[0052] Advantageously, the ratio VTV / FPKV of vacuum tank volume (VTV) of the vacuum tank (VT) to free process chamber volume (FPKV) of the process chamber (PK1, PK2, PK3) above the solvent (LM) is within a range of 10 to 400 (10 < VTV / FPKV < 400) and preferably within a range of 10 to 300 (10 < VTV / FPKV < 300) and most preferably in the range of 10 to 200 (10 < VTV / FPKV < 200).

[0053] Preferably, an ultrasound source (US, US1, US2, US3) can be assigned to a process chamber (PK1, PK2, PK3), or an ultrasound source (US, US1, US2, US3) is assigned to a process chamber (PK1, PK2, PK3) in a processing position.

[0054] Preferably, each process chamber (PK1 , PK2, PK3) is assigned a respective ultrasound source (US1 , US2, US3), wherein preferably each ultrasound source generates a different ultrasound frequency or a different group or combination of ultrasound frequencies.

[0055] Preferably, the process chamber (PK1 , PK2, PK3), into which the workpiece to be treated can be placed, includes a means for moving the placed workpiece relative to the process chamber and relative to the solvent (LM).

[0056] Preferably, the device includes a drying fan (TV) which can be brought into fluid contact with the process chamber (PK1, PK2, PK3) and a treated workpiece contained therein for drying. Preferably, a second valve (V2) is included in the fluid connection containing the drying fan (TV) and the process chamber (PK1, PK2, PK3).

[0057] An atmosphere valve (AV) is arranged, wherein preferably an air filter (LV) is arranged upstream of the drying fan (TV) and preferably a heating unit (HE) for the drying air is arranged downstream of the drying fan (TV).

[0058] Preferably the device contains several process chambers (PK1 , PK2, PK3), in particular at least three process chambers.

[0059] Each of the multiple process chambers can be filled with at least one solvent.

[0060] A process chamber can also be filled with various treatment fluids.

[0061] In this system, each successive treatment step can be carried out in a separate process chamber filled with the specific treatment fluid required for that step. This results in a sequence of process chambers, each containing the treatment fluid necessary for its respective step. The workpiece to be treated is then successively immersed in the respective treatment fluid within the corresponding process chamber and treated using that fluid.

[0062] During a treatment step in a respective process chamber, several different treatment fluids can be filled into the respective process chamber simultaneously and as a mixture.

[0063] The respective treatment steps can be carried out in the respective process chamber either at atmospheric pressure or under vacuum with an active vacuum pump and the first valve or vacuum pump valve open. Preferably, the device includes a positioning unit (PE) to which the several process chambers (PK1, PK2, PK3) are fixed side by side, wherein the positioning unit can position one of the process chambers in a processing position within the device.

[0064] The process chambers can be arranged on a circular arc or on an entire circular line, wherein the process chambers arranged in this way can be rotated by rotation about an axis of rotation passing through the center of the circular arc or circular line.

[0065] The process chambers can alternatively be arranged on a straight line, whereby the process chambers arranged in this way can be translated along the straight line.

[0066] Preferably the device includes a receiving unit (AE) for a workpiece to be treated, wherein the receiving unit (AE) is movable relative to a process chamber (PK1 , PK2, PK3).

[0067] The receiving unit can be a cage or a basket.

[0068] Preferably, the device includes a translation unit (TE) by means of which the receiving unit (AE) can be moved into and out of a process chamber (PK1 , PK2, PK3).

[0069] Preferably, the vacuum tank (VT) is assembled from several vacuum tank components and can be reversibly disassembled, wherein the assembled vacuum tank (VT) has sealing means, at least in contact areas of the vacuum tank wall sections of adjacent vacuum tank components, which are clamped between adjacent vacuum tank components.

[0070] Preferably, the device includes a control unit by means of which at least one of the following elements can be controlled:

[0071] - first valve (V1) or vacuum pump valve (W2)

[0072] - second valve (V2) or atmospheric valve (AV)

[0073] - Closure unit (VE) - Vacuum pump (VP) - Ultrasonic source (US, US1, US2, US3)

[0074] - Drying fan (TV)

[0075] - Positioning unit (PE)

[0076] - Translation unit (TU)

[0077] - Unit of rotation (RE)

[0078] - Heating unit (HE) for drying air

[0079] - Heating unit (HU) for process chamber

[0080] According to a third aspect, the invention provides a method for treating workpieces, in particular for surface treatment of workpieces, and in particular using the device (1) described above, wherein the method comprises the following steps: a) placing a workpiece to be treated into a receiving unit (AE); b) inserting the receiving unit (AE) with the workpiece to be treated into a process chamber (PK1, PK2, PK3); c) filling the process chamber (PK1, PK2, PK3) with at least one solvent (LM) up to a fill level corresponding to a partial filling of the process chamber with solvent (LM); d) hermetically sealing the process chamber (PK1, PK2, PK3) by means of a sealing unit (VE), which is in particular attached to the receiving unit (AE); e) evacuating the process chamber (PK1, PK2, PK3) by means of a vacuum pump (VP);h) Removal of solvent (LM) from the process chamber (PK1, PK2, PK3) and from the treated workpiece; i) Opening of the process chamber (PK1, PK2, PK3) using the closure unit (VE); j) Removal of the receiving unit (AE) with the treated workpiece from the process chamber (PK1, PK2, PK3); k) Removal of the treated workpiece from the receiving unit (AE).

[0081] According to a fourth aspect, the invention provides a method for treating workpieces, in particular for surface treatment of workpieces, and in particular using the device (1) described above, wherein the method comprises the following steps: a) placing a workpiece to be treated into a receiving unit (AE); b) inserting the receiving unit (AE) with the workpiece to be treated into a process chamber (PK1, PK2, PK3); c) filling the process chamber (PK1, PK2, PK3) with at least one solvent (LM) up to a fill level corresponding to a partial filling of the process chamber with solvent (LM); d) hermetically sealing the process chamber (PK1, PK2, PK3) by means of a sealing unit (VE), which is in particular attached to the receiving unit (AE); e*) evacuating a vacuum tank (VT) by means of a vacuum pump (VP);f1) Establishing a first fluid connection between a location above the fill level of the solvent-filled process chamber (PK1, PK2, PK3) and the vacuum tank (VT) by opening a first valve (V1); g1) Blocking the first fluid connection by closing the first valve (V1); f2) Establishing a second fluid connection between a location above the fill level of the solvent-filled process chamber (PK1, PK2, PK3) and the atmosphere by opening a second valve (V2); g2) Blocking the second fluid connection by closing the second valve (V2); h) Removing solvent (LM) from the process chamber (PK1, PK2, PK3) and from the treated workpiece; i) Opening the process chamber (PK1, PK2, PK3) by means of the closure unit (VE); j) Removing the receiving unit (AE) with the treated workpiece from the process chamber (PK1, PK2, PK3); k) Removing the treated workpiece from the receiving unit (RU).;

[0082] Preferably, after opening the first valve (V1 ) in step f1 ), the first valve (V1 ) is closed in step g1 ), before more than 1 / 10, preferably more than 1 / 100, of the volume of the solvent (LM) has passed through the first valve (V1 ).

[0083] This can be achieved by a foam sensor and / or by holding the valve open for a sufficiently short time between steps f1) and g1). Preferably, ultrasound is introduced into the solvent (LM) from an ultrasonic source (US, US1, US2, US3) during at least one of steps c) to h).

[0084] Preferably, before step f1 ) ultrasound is introduced into the solvent (LM) from an ultrasound source (US, US1 , US2, US3).

[0085] The different ultrasound sources can emit ultrasound of different frequencies and / or different amplitudes.

[0086] Thus, in each treatment step with a different treatment fluid, different ultrasound frequencies and / or different ultrasound amplitudes can act on the treatment fluid and the workpiece surface.

[0087] Preferably, during at least one of steps c) to h), the workpiece is moved relative to the process chamber and relative to the solvent (LM).

[0088] Moving the workpiece ensures that the entire surface is adequately exposed to treatment fluid and ultrasound.

[0089] Preferably, the removal of solvent (LM) from the process chamber (PK1 , PK2, PK3) and from the treated workpiece in step h) includes rotating the receiving unit (AE) with the cleaned workpiece, wherein the receiving unit is rotated about a rotational axis by means of a rotation unit (RE).

[0090] Such a centrifugal process removes a large portion of the treatment fluid adhering to the workpiece.

[0091] Preferably, the removal of solvent (LM) from the process chamber (PK1 , PK2, PK3) and from the treated workpiece in step h) includes drying the cleaned workpiece in the process chamber (PK1 , PK2, PK3) by means of a drying fan (TV), wherein a heating unit (HE) for the drying air is preferably arranged between the drying fan and the respective process chamber (PK1 , PK2, PK3).

[0092] Preferably, the sequence of steps e*), f1 ), g1 ), f2), g2) is repeated several times in one of the process chambers (PK1 , PK2, PK3).

[0093] Preferably, step e*) of evacuation continues continuously, while the sequence of steps f1 ), g1), f2), g2) is repeated several times in one of the process chambers (PK1 , PK2, PK3).

[0094] Preferably, the sequence of steps b) to j) is repeated several times and each time in different process chambers (PK1 , PK2, PK3).

[0095] Preferably, after drying and heating the treated workpiece in a process chamber (PK1 , PK2, PK3) steps e*) and f1 ) are carried out again.

[0096] Preferably, the sequence of steps f1), g1), f2) and g2) is repeated several times.

[0097] Preferably, when establishing the first fluid connection by opening the first valve (V1) in step f1), a pressure drop Ap occurs at the location above the fill level of the solvent-filled process chamber (PK1, PK2, PK3) during a time period At, from an initial pressure p1 to a final pressure p2, wherein the initial pressure p1 is between 0.9 bar and 1.1 bar (0.9 bar < p1 < 1.1 bar), the final pressure p2 is between 0.01 bar and 0.3 bar (0.01 bar < p2 < 0.3 bar), and the time period At is in the range of 50 ms to 200 ms (50 ms < At < 200 ms).

[0098] Preferably the solvent (LM) has a temperature in the range of 10°C to 70°C and preferably in the range of 20°C to 50°C.

[0099] Preferably, the treatment includes passivating the surface of the workpiece. Preferably, the treatment includes cleaning the surface of the workpiece.

[0100] Preferably, the treatment includes cleaning the surface of the workpiece and passivating the surface of the workpiece.

[0101] Surface passivation can be carried out after surface cleaning or simultaneously with surface cleaning.

[0102] Surfactants and / or solvents are preferably used for surface cleaning.

[0103] The surfactants reduce the surface tension of water, resulting in better wetting of the surface and better removal of contaminants from the workpiece surface.

[0104] Preferably, organic solvents and / or inorganic solvents are used.

[0105] The organic solvents are used, among other things, to remove grease residues from the workpiece surface.

[0106] An example of an organic solvent is acetone.

[0107] The inorganic solvents are used, among other things, to remove metal particles from the workpiece surface.

[0108] For passivation, for example nitric acid, hydrochloric acid or citric acid are used.

[0109] Acid mixtures containing at least one of these acids can also be used.

[0110] The use of citric acid is particularly preferred for passivation.

[0111] According to a fifth aspect, the invention provides a method for treating workpieces using a device according to one of the preceding paragraphs, the method comprising: a) introducing a workpiece (W) into a process chamber (PK1, PK2, PK3); b) establishing a fluid connection between the branching region (VB) and the vacuum pump (VP) or between the process chamber (PK1, PK2, PK3) and the vacuum pump (VP); c) interrupting the fluid connection between the branching region (VB) or the process chamber (PK1, PK2, PK3) and the vacuum pump (VP); d) establishing a fluid connection between the branching region (VB) and a purge gas source (AT); e) interrupting the fluid connection between the branching region (VB) and the purge gas source (AT).

[0112] Preferably, the sequence of steps b), c), d) and e) is repeated several times.

[0113] The purge gas source (AT) can consist of air, especially atmospheric air. Purging the connection area (VB) with atmospheric air is cost-effective.

[0114] The purge gas source (AT) can comprise an inert gas, in particular nitrogen or argon, preferably pure nitrogen or a nitrogen / argon mixture, preferably with less than 1 vol% oxygen.

[0115] Thus, the connection area (VB) can be purged with such an inert gas.

[0116] Preferably, a first purge gas source contains air and a second purge gas source contains an inert gas, in particular nitrogen or argon.

[0117] Therefore, the connection area (VB) can be flushed with air or with inert gas.

[0118] Preferably, when performing steps d) and e), the first purge gas source is used first, and the second purge gas source is used when performing steps d) and e) last. Thus, the bonding area (VB) is purged with air at the beginning, tolerating the oxygen it contains. In contrast, at the end, i.e., before the workpiece dries, the bonding area (VB) is purged with an inert gas, tolerating no oxygen or only a very small amount.

[0119] Preferably, the method according to steps b), c), d) and e) includes as a further step f) drying the workpiece (W).

[0120] Preferably, step f) is carried out in an inert gas environment.

[0121] This prevents oxidation of the workpiece surface.

[0122] Preferably, the device according to the invention includes at least one ultrasound source by means of which a workpiece contained in a process chamber and a treatment fluid surrounding it can be exposed to ultrasound.

[0123] Preferably, the inventive method includes at least one step in which a workpiece contained in a process chamber and a treatment fluid surrounding it are exposed to ultrasound.

[0124] Further advantages, features and application possibilities of the invention will become apparent from the following description of exemplary embodiments of the device according to the invention, which are not to be understood as limiting, based on the drawing, wherein:

[0125] Fig. 1 shows a first perspective view of a first embodiment of the device according to the invention;

[0126] Fig. 2 shows the perspective view of the first embodiment of the device according to the invention in a partially cut-open state;

[0127] Fig. 3 shows a second perspective view of the first embodiment of the device according to the invention in a partially cut-open state;

[0128] Fig. 4 shows a third perspective view of the first embodiment of the device according to the invention in a partially cut-open state;

[0129] Fig. 5 shows a perspective view of a first assembly of the first embodiment of the device according to the invention as shown in Fig. 2, Fig. 3 and Fig. 4;

[0130] Fig. 6 shows a perspective view of a second assembly of the first embodiment of the device according to the invention, as shown in Fig. 3 and Fig. 4;

[0131] Fig. 7 shows a perspective view of a partially cut-open process chamber of a second embodiment of the device according to the invention;

[0132] Fig. 8 shows a side view of the partially cut-open process chamber of the second embodiment of the device according to the invention;

[0133] Fig. 9 shows a perspective view of a partially cut-open process chamber of a third embodiment of the device according to the invention;

[0134] Fig. 10 shows a side view of the partially cut-open process chamber of the third embodiment of the device according to the invention; Fig. 11 is a schematic view of a fourth embodiment of the device according to the invention;

[0135] Fig. 12 (with W2 and without VV3) is a schematic view of a fifth embodiment of the device according to the invention;

[0136] Fig. 12 (without VV2 and with VV3) is a schematic view of a sixth embodiment of the device according to the invention;

[0137] Fig. 13 is a schematic sectional view of an exemplary embodiment of a channel constriction of the device according to the invention;

[0138] Fig. 14 is a schematic sectional view of a further exemplary embodiment of a channel constriction of the device according to the invention; and

[0139] Fig. 15 shows a particularly preferred embodiment of the device according to the invention.

[0140] Figure 1 shows a first perspective view of a first embodiment of the device 1. A cabinet-like or box-like housing GV of the device is visible. The housing GV has a substantially rectangular base. On its underside, it has four wheels R, each located in the area of ​​a corner of the base of the housing GV. On one side wall (front wall), the housing GV has an operating panel BP, on which process parameters can be set or measured process parameters can be read. On the same side wall (front wall), the housing GV also has two access doors ZT, which provide access to the actual process chambers PK1, PK2, PK3 (see Figure 2) and further process chambers (not shown in Figure 2) in which workpieces (not shown) can be cleaned.

[0141] Figure 2 shows a perspective view of the first embodiment of device 1 in a partially cutaway state (part of the front wall of housing GV removed). Three process chambers, PK1, PK2, and PK3, are visible, attached to a positioning unit PE between a positioning unit upper part PEO and a positioning unit lower part PEU. Three further process chambers within the positioning unit PE are obscured and therefore not shown. The positioning unit PE is rotatable about a vertical axis of rotation, allowing each of the six process chambers to be moved into a processing position. In the state shown in Figure 2, process chamber PK2 is in its processing position.

[0142] Above the positioning unit PE with its six process chambers PK1, PK2, PK3 (and three others) is a receiving unit AE in which a workpiece to be cleaned (not shown) can be positioned. The receiving unit AE is cage-shaped, into which, for example, a basket (not shown) containing one or more workpieces to be cleaned can be inserted. The receiving unit AE is attached to the lower end of a translation unit TE and a rotation unit RE.

[0143] Using the translation unit TE, the receiving unit AE can be lowered into the process chamber PK2 located below, which is in its processing position, along a translation axis, after or before the process chamber PK2 is filled with solvent (LM).

[0144] The RE rotation unit allows the receiving unit AE, lowered into process chamber PK2, to be rotated about a vertical axis of rotation that coincides with the translational axis. This rotation can be used to spin / centrifuge the receiving unit AE in process chamber PK2 to pre-dry workpieces positioned in the receiving unit AE. Figure 2 also shows an assembly 2, which contains a first valve V1 and a second valve V2. Assembly 2 is shown in more detail in Figure 5. The first valve V1 is connected to a vacuum source in the form of a vacuum tank VT (see Figure 3) via a first hose line SL1 (shown with dashed lines). The second valve V2 is connected to the atmosphere via a second hose line SL2 (shown with dashed lines). A heating unit HK is attached to each of the two process chambers PK1 and PK2 for heating the respective process chamber.Preferably, the heating unit HK is a resistive heating film which is embedded in the wall of the respective process chamber.

[0145] An ultrasound source US1 or US2 is installed in the floor of each of the two process chambers PK1 and PK2.

[0146] Figure 3 shows a second perspective view of the first embodiment of the device 1 in a partially cutaway state (part of the front wall and the left side wall of the housing GV removed). As in Figure 2, the receiving unit AE arranged above the process chamber PK2 can be seen. The hose lines SL1 and SL2, shown with dashed lines, are also visible.

[0147] The process chamber PK2 can also be seen, to which the heating unit HK is attached for heating the process chamber.

[0148] Furthermore, it can be seen that an ultrasound source US2 is installed in the floor of process chamber PK2.

[0149] Figure 4 shows a third perspective view of the first embodiment of the device 1 in a partially cutaway state (the entire front wall and the entire right side wall of the housing GV have been removed). The process chambers PK2, PK3, and PK4 are visible. Process chamber PK2 is located below the receiving unit AE in its processing position. Also visible is the sealing unit VE, arranged on the assembly 2, which allows the upper opening of process chamber PK2 to be hermetically sealed in its processing position.

[0150] In the lower part of apparatus 1, a vacuum pump VP is visible, which serves to evacuate the vacuum tank VT. The vacuum pump VP is connected to the vacuum tank VT via its connecting pipe A2", a third hose line SL3 (shown with dashed lines), a vacuum pipe VR, and a fourth hose line SL4 (shown with dashed lines). The vacuum pump VP can be operated continuously to provide a constant vacuum in the vacuum tank VT. When the first valve V1 is open, the vacuum in the vacuum tank VT draws air from the process chamber PK2, thus also creating a vacuum in the process chamber PK2. Since the volume of the vacuum tank VT is much larger than the liquid-free volume of the process chamber PK2 above the solvent (LM) fill level, opening the first valve V1 can generate a sudden pressure drop in the process chamber PK2 and in the solvent (LM) it contains.By alternately opening and closing the first valve V1 and alternately opening and closing the second valve V2, i.e., by repeatedly performing steps f1), g1), f2), g2), while continuously operating the vacuum pump VP, numerous successive pressure drops or pressure surges can be achieved in the process chamber PK2.

[0151] Furthermore, the lower part of device 1 shows a drying fan TV with an upstream air filter LF for the drying air and a downstream heating unit HE for the drying air. The process chamber PK2, in its processing position, is located downstream of the heating unit HE in the drying air line. When the second valve is open, the drying fan TV pushes drying air through the process chamber PK2 and out into the atmosphere via the second hose SL2.

[0152] Each of the two process chambers PK2 and PK4 has a heating unit HK attached for heating the respective process chamber.

[0153] An ultrasound source US2 or US4 is installed in the floor of each of the two process chambers PK2 and PK4.

[0154] Figure 5 shows a perspective view of a first assembly 2 of the first embodiment of the device 1, as shown in Figures 2, 3, and 4. Assembly 2 comprises the first valve V1 and the second valve V2. A connecting pipe AT is located on the first valve V1, to which the first hose line SL1 is connected (see Figures 2, 3, and 4). A connecting pipe A2' is located on the second valve V2, to which the second hose line SL2 is connected (see Figures 2, 3, and 4). Assembly 2 also includes a sealing unit VE, with which the upper opening of the process chamber PK2 can be hermetically sealed. A foam sensor SS is arranged in the resulting channel between the first valve V1 and the process chamber PK2. If opening the first valve V1 causes excessive foaming of the solvent (LM) in the process chamber PK2, for example because its temperature is too high and / or because of, for example,If the liquid level in process chamber PK2 is too high, solvent (LM) could be drawn into vacuum tank VT. This must be prevented so that vapors from the solvent (LM) do not destroy the vacuum created in vacuum tank VT by the vacuum pump VP. If the foam sensor SS detects foam in the channel, this signal can be used by a control unit to immediately close the first valve V1.

[0155] In addition to or as an alternative to the foam sensor SS, the first valve V1 can be controlled to open as quickly as possible ("suddenly") and close as quickly as possible ("suddenly") after a short time in the open position. This also prevents solvent (LM) from being drawn into the vacuum tank VT as foam or vapor.

[0156] Assembly 2 also includes a pressure sensor DS for detecting the pressure in the respective process chamber, which is located below assembly 2 in its processing position (process chamber PK2 in Fig. 2, Fig. 3, Fig. 4). The pressure sensor DS is located on the underside of the closure unit VE and is therefore not visible in Fig. 5.

[0157] Assembly 2 also contains an ultrasonic source US for introducing ultrasound into the respective process chamber, which is located below assembly 2 in its processing position (process chamber PK2 in Fig. 2, Fig. 3, Fig. 4). The ultrasonic source US is located on the underside of the closure unit VE and is therefore not visible in Fig. 5. Thus, in addition to the ultrasonic sources US1, US2, US3, etc., specific to each process chamber PK1, PK2, PK3, etc., the ultrasonic source US represents an additional ultrasonic source.

[0158] The assembly 2 shown in Fig. 5 corresponds approximately to the connection area VB shown in Fig. 15.

[0159] Figure 6 shows a perspective view of a second assembly of the first embodiment of the device 1, as shown in Figures 3 and 4. This second assembly forms the vacuum tank VT. It is connected to the process chamber PK2 via its connecting pipe A1, the first hose line SL1 (see Figures 2, 3, and 4), and the connecting pipe AT of the first valve 1 (see Figure 5). Furthermore, the vacuum tank VT is connected to the vacuum pump VP via its connecting pipe A2, the fourth hose line SL4, the vacuum pipe VR, the third hose line SL3 (see Figure 4), and the connecting pipe A2".

[0160] It can also be seen that the cuboid housing GT of the vacuum tank VT is stabilized by means of a perforated stiffening plate VPT and numerous stiffening supports VST. The stiffening plate VPT extends parallel between two opposing large surfaces of the housing GT. The stiffening plate VPT also extends from one small surface to the other of two opposing pairs of small surfaces (end surfaces) of the housing GT. The stiffening supports VST extend through the holes in the perforated stiffening plate VPT, parallel to the small surfaces (end surfaces) and orthogonal to the two large surfaces.

[0161] Figure 7 shows a perspective view of a partially cut-open process chamber PK of a second embodiment of the device 1. The process chamber PK is partially filled with a solvent LM, e.g., XYZ. The receiving unit AE is immersed in the solvent LM. A basket (not shown), containing one or more workpieces to be cleaned (not shown), can be inserted into the cage-like receiving unit AE. The receiving unit AE is mounted at the lower end of a combined translation / rotation unit TE / RE, by means of which the receiving unit AE, together with the workpieces contained therein, can be moved linearly up and down along a vertical axis and rotated back and forth around this vertical axis.

[0162] A shielding agent, SM, floats on the upper surface of the solvent LM. In this case, SM is in the form of a plate or mat P / M, whose density is lower than that of the solvent LM. The plate or mat P / M is sized to cover a large portion of the upper surface of the solvent LM. The process chamber PK can have any shape. A gap AS and IS exists between the edges of the plate or mat P / M and the inner boundary surfaces of the process chamber PK. This gap prevents the plate or mat P / M from becoming stuck inside the process chamber PK. This allows for easy removal of the plate or mat P / M from the process chamber PK or for its rotation within the process chamber PK before it is filled with solvent LM.

[0163] Preferably, as shown in Fig. 7, the process chamber PK is cylindrical. The plate or mat P / M, which surrounds the translation / rotation unit TE / RE, is therefore annular in shape. Consequently, there is an inner gap IS between the inner edge of the plate or mat P / M and the translation / rotation unit TE / RE, and an outer gap AS between the outer edge of the plate or mat P / M and the inner surface of the cylindrical process chamber PK. The inner gap IS and the outer gap AS each have a width in the range of 1 mm to 7 mm, thus ensuring both sufficient shielding and good mobility of the plate or mat P / M.

[0164] Figure 8 shows a side view of the partially cut-open process chamber PK of the second embodiment of the device 1. The solvent LM in the lower region of the process chamber PK, the receiving unit AE immersed therein, and the shielding agent SM in the form of the plate or mat P / M are visible. Also visible are the inner gap IS between the plate or mat P / M and the translation / rotation unit TE / RE, and the outer gap AS between the plate or mat P / M and the inner surface of the cylindrical process chamber PK. Figure 9 shows a perspective view of a partially cut-open process chamber PK of a third embodiment of the device 1.The third version differs from the second only in that, instead of a floating plate or mat P / M, a multitude of bulk solids SK are provided as a layer or packing of material as a shielding medium SM. The density of the bulk solids SK is lower than the density of the solvent LM, so that the bulk solids SK float on the surface of the solvent LM. Depending on the number and size of the bulk solids SK, several layers of bulk solids SK can accumulate on the surface of the solvent LM. The bulk solids SK are rounded bodies in the form of spheres, pellets, etc.

[0165] The bulk material bodies SK can be in the form of loose bulk material or packing. Alternatively, they can be in the form of a sintered plate or a sintered block made of SK bulk material bodies that are bonded together or melted together.

[0166] Preferably, as shown in Fig. 9, the process chamber PK is cylindrical. The loose fill or sintered block of bulk material SK surrounds the translation / rotation unit TE / RE and therefore has approximately the shape of a ring.

[0167] Figure 10 shows a side view of the partially cut-open process chamber PK of the third embodiment of the device 1. The solvent LM can be seen in the lower region of the process chamber PK, the receiving unit AE immersed therein, and the shielding agent SM in the form of several layers of bulk material SK, which are piled up between the translation / rotation unit TE / RE and the inner surface of the cylindrical process chamber PK.

[0168] Fig. 11 is a schematic view of a fourth embodiment of the device according to the invention.

[0169] The fourth version has only one initial channel narrowing KE1.

[0170] The second vacuum valve W2 is located in a second channel section K2 between the branching area VB and the vacuum pump VP, or between the channel constriction KE1 and the vacuum pump VP. The vacuum pump VP is connected to a vacuum tank (not shown) via a fluid flow system.

[0171] The first vacuum valve W1 shown in channel section K1 is optional and can therefore be omitted.

[0172] Fig. 12 (with W2 and without W3) is a schematic view of a fifth embodiment of the device according to the invention.

[0173] The fifth version has a first channel narrowing KE1 in a first container B1 and a second channel narrowing KE2 in a second container B2.

[0174] The second vacuum valve W2 is located here in the second channel section K2 between the branching area VB and the second channel constriction KE2, or between the first channel constriction KE1 and the second channel constriction KE2. The vacuum pump VP is in fluid communication with a vacuum tank (not shown).

[0175] The third vacuum valve W3 shown in channel section K2 is optional and can therefore be omitted.

[0176] Fig. 12 (without W2 and with W3) is a schematic view of a sixth embodiment of the device according to the invention.

[0177] The sixth version also has a first channel narrowing KE1 and a second channel narrowing KE2.

[0178] The third vacuum valve VV3 is located here in the second channel section K2 between the second channel constriction KE2 and the vacuum pump VP.

[0179] The second vacuum valve VV2 shown in the second channel section K2 is optional and can therefore be omitted. In this case, the first container B1 and the second container B2 form a common container (see Fig. 14) in which the first channel constriction KE1 and the second channel constriction KE2 are arranged side by side. The vacuum pump VP is in fluid communication with a vacuum tank (not shown).

[0180] Fig. 13 shows a schematic sectional view of an exemplary embodiment of the first channel constriction KE1 along a channel axis according to the invention.

[0181] The diagram shows a widening area AB and a basin-like depression BS, in which accumulated treatment fluid BF is shown. The first channel constriction KE1 serves as an overflow for treatment fluid BF in the basin-like depression BS.

[0182] Fig. 14 shows a schematic sectional view of a further exemplary embodiment of a channel narrowing or first channel narrowing KE1 along a channel axis according to the invention.

[0183] The widening area AB and the pelvic depression BS, in which accumulated treatment fluid BF is shown, can again be seen.

[0184] The first channel narrowing KE1 serves as an overflow for the basin-like depression BS.

[0185] A further channel narrowing or second channel narrowing KE2 is arranged offset along the channel axis to the first channel narrowing KE1.

[0186] The second channel constriction KE2 also serves as an overflow for treatment fluid BF to the basin-like depression BS.

[0187] Fig. 15 shows a particularly preferred embodiment of the branching area VB. The first channel section K1, the second channel section K2, and the third channel section K3, all of which flow into the branching area VB, can be seen.

[0188] The branching region VB is a funnel-shaped chamber with a conical outer surface, as shown in Fig. 15. The branching region VB is shown in a state partially filled with treatment fluid BF.

[0189] According to a first alternative, the funnel-shaped chamber can have a concave outer surface, which roughly corresponds to a tulip-like chamber shape. According to a second alternative, the funnel-shaped chamber can have a convex outer surface, which roughly corresponds to a chanterelle-like chamber shape. Regardless of the aforementioned chamber shapes (conical, concave, convex), the round or rounded inner shape, and especially the rotational symmetry, of the funnel-shaped chamber is particularly advantageous.

[0190] The first channel section K1 is in fluid communication with, or can be brought into fluid communication with, the process chambers PK1, PK2, and PK3, for which the first vacuum valve W1 is provided. This fluid connection has a first channel constriction KE1. The first vacuum valve W1 is a slide valve with a spool SW1. This first vacuum valve VV1, or slide valve with spool SW1, can also be omitted from the fluid connection.

[0191] The second channel section K2 is in fluid communication with the vacuum pump VP, or can be brought into fluid communication with it, for which purpose the second vacuum valve W2 is provided. This fluid connection has a second channel constriction KE2. The second vacuum valve W2 is also a spool valve (spool not shown).

[0192] The third channel section K3 is in fluid contact with the atmosphere AT or with a purge gas source (not shown), or can be brought into fluid contact with it, for which purpose the atmosphere valve AV is provided. The atmosphere valve AV is a diaphragm valve with a diaphragm MAV. An inert gas or an inert gas mixture, in particular argon or nitrogen, can be used as the purge gas.

[0193] The third channel section K3, which is intended for purging the branching region VB with air or an inert gas, opens into the funnel-shaped chamber of the branching region VB along a channel outlet direction of the third channel section K3, which is offset with respect to the round or rounded inner shape of the funnel-shaped chamber, in particular with respect to the rotational symmetry axis of the funnel-shaped chamber and has a tangential component as well as a radial component with respect to the rounded inner shape.

[0194] It is particularly advantageous if, in the direction of the channel mouth, the tangential component is larger than the radial component, or if the radial component is even zero.

[0195] Furthermore, it is advantageous if the channel outlet direction of the third channel section K3 is inclined towards the funnel-shaped chamber, specifically downwards, or if it has an axial component directed towards the funnel outlet or the tapered end of the funnel, relative to the rounded inner shape. All of this contributes to minimizing turbulence when rinsing the branching area VB or the widening area AB with air or an inert gas, thus preventing splashing and / or foaming of the treatment fluid BF when emptying the connection area VB.

[0196] Any vapors, especially water vapor, in the branching region VB are cooled during expansion, causing at least partial condensation on the inner wall of the branching region VB. The resulting condensate, especially water, is returned to the process chambers PK1, PK2, and PK3 when the atmosphere valve AV is opened. Thus, only a small amount of liquid enters the vacuum tank (not shown).

[0197] The connection area VB shown in Fig. 15 corresponds approximately to the assembly 2 shown in Fig. 5.

[0198] Reference symbol list

[0199] 1 Device for treating workpieces

[0200] 2 Valve assembly

[0201] GV housing of the device

[0202] BP control panel

[0203] ZT access door

[0204] R wheel

[0205] PK Trial Chamber

[0206] PK1 first trial chamber

[0207] PK2 second trial chamber

[0208] PK3 third trial chamber

[0209] PK4 fourth trial chamber

[0210] LM solvents

[0211] VE closure unit

[0212] VP vacuum pump

[0213] VT vacuum tank

[0214] GT Tank Housing

[0215] VPT tank stiffening plate

[0216] VST tank stiffening support

[0217] A1 Connecting pipe (of the vacuum tank) for process chamber connection

[0218] A2 Connection pipe (of the vacuum tank) for vacuum pump connection

[0219] A1 ' Connecting pipe (of the valve assembly) for vacuum tank connection

[0220] A2' Connecting pipe (of the valve assembly) for exhaust air connection to the atmosphere

[0221] A2" connection pipe (of the vacuum pump) for process chamber connection

[0222] V1 first valve or vacuum pump valve

[0223] (between vacuum tank and process chamber)

[0224] V2 second valve or atmospheric valve

[0225] (between vacuum tank and atmosphere)

[0226] VTV vacuum tank volume

[0227] Private health insurance trial chamber volume

[0228] AE mounting unit for workpiece to be cleaned

[0229] DS pressure sensor for process chamber pressure

[0230] US ultrasound source US1 first ultrasound source (at first process chamber)

[0231] US2 second ultrasound source (at second process chamber)

[0232] US3 third ultrasound source (at third process chamber)

[0233] US4 fourth ultrasound source (at fourth process chamber)

[0234] PE positioning unit

[0235] PEO Positioning Unit Top

[0236] PEU Positioning Unit Lower Part

[0237] LF air filter (for drying air)

[0238] HE heating unit (for drying air)

[0239] HK heating unit (for process chamber)

[0240] TV drying fan

[0241] TE Translation unit (for recording unit)

[0242] RE Rotation Unit (for recording unit)

[0243] SM shielding agent

[0244] P / M board or mat

[0245] SK bulk material body

[0246] IS inner gap

[0247] AS outer gap

[0248] SS foam sensor

[0249] SL1 first hose line

[0250] SL2 second hose line

[0251] SL3 third hose line

[0252] SL4 fourth hose line

[0253] VR vacuum tube

[0254] W workpiece

[0255] BF treatment fluid

[0256] VP vacuum pump

[0257] VB branching area

[0258] K1 first canal section

[0259] K2 second canal section

[0260] K3 third canal section

[0261] W1 first vacuum valve (in version 1 according to Figure 1) or process chamber valve W2 second vacuum valve (in version 2 according to Figure 2) or vacuum pump valve

[0262] W3 third vacuum valve (in version 3 according to Figure 2) or further vacuum pump valve

[0263] KE1 first channel narrowing

[0264] KE2 second channel narrowing

[0265] B1 first container

[0266] B2 second container

[0267] AT Purge gas source (atmosphere and / or inert gas source)

[0268] AV atmospheric valve

[0269] AB expansion area

[0270] BS pelvic depression

[0271] SW1 slider from W1

[0272] MAV membrane of AV

Claims

Claims 1. Device (1) for treating workpieces, in particular for surface treatment of workpieces, wherein the device comprises: a process chamber (PK1, PK2, PK3) into which a workpiece to be treated can be placed and which can be at least partially filled or is filled with at least a solvent (LM); a closure unit (VE) for opening and closing the process chamber (PK1, PK2, PK3); and a vacuum pump (VP) which can be brought into fluid communication with the process chamber (PK1, PK2, PK3) for evacuating the process chamber; characterized in that a first valve (V1) is arranged in the fluid connection between the process chamber (PK1, PK2, PK3) and the vacuum pump (VP).

2. Device according to claim 1, characterized in that a branching area (VB) is arranged in the fluid connection between the vacuum pump (VP) and the process chamber (PK1, PK2, PK3), into which a first channel section (K1), a second channel section (K2) and a third channel section (K3) open; wherein - the first channel section (K1 ) is in fluid connection with the process chamber (PK1 , PK2, PK3) or can be brought into fluid connection and has a first channel constriction (KE1 ); - the second channel section (K2) can be brought into fluid contact with the vacuum pump (VP); and - the third channel section (K3) can be brought into fluid contact with a purge gas source (AT); wherein a basin-like depression (BS) is provided in the branching area (VB) between the channel constriction (KE1) and the second channel section (K2), the fluid outlet of which is formed by the channel constriction (KE1) or for which the channel constriction (KE1) forms a fluid outlet.

3. Device according to claim 2, characterized in that a vacuum pump valve (W2) is arranged in the second channel section (K2), with which the fluid connection between the branching area (VB) and the vacuum pump (VP) can be established or interrupted.

4. Device according to claim 2 or 3, characterized in that an atmospheric valve (AV) is arranged in the third channel section, with which the fluid connection between the branching area (VB) and the purge gas source (AT) can be established or interrupted.

5. Device according to one of claims 2 to 4, characterized in that the channel constriction (KE1 ) on the side of the branching area (VB) has a widening area (AB) which widens from an area with a minimum flow cross-section to an area with a maximum flow cross-section (e.g. funnel-shaped).

6. Device according to claim 5, characterized in that the widening area (AB) forms a part of the basin-like depression (BS) or forms a transition from the area with minimal flow cross-section to the basin-like depression (BS).

7. Device according to claim 6, characterized in that the expansion area (AB) has a funnel-shaped form or is designed in a funnel-like manner.

8. Device according to claim 7, characterized in that the inner surface of the expansion area (AB) has a) conically or b) concavely or c) convexly shaped area.

9. Device according to claim 7 or 8, characterized in that the first channel constriction KE1 is arranged at a funnel outlet area or at the tapered end of the funnel-shaped form, wherein the funnel-shaped form opens into the first channel section (K1) with its tapered end.

10. Device according to claim 9, characterized in that a first vacuum valve (W1 ) is arranged at the funnel outlet area or at the tapered end of the funnel-shaped form.

11. Device according to one of claims 7 to 10, characterized in that a second channel constriction KE2 is arranged at a funnel inlet area or at a flared end of the funnel-shaped form, wherein the funnel-shaped form opens into the second channel section (K2) at its flared end.

12. Device according to claim 11, characterized in that a second vacuum valve (W2) is arranged at the funnel inlet area or at the flared end of the funnel-shaped form.

13. Device according to one of claims 7 to 12, characterized in that an atmosphere valve (AV) is arranged at a funnel inlet area or at a flared end of the funnel-shaped form, wherein the funnel-shaped form opens into the third channel section (K3) at its flared end.

14. Device according to claim 13, characterized in that the third channel section (K3) opens into the funnel-shaped chamber of the branching region VB along a channel outlet direction of the channel section (K3), which is offset with respect to the round or rounded inner shape of the funnel-shaped chamber, in particular with respect to the rotational symmetry axis of the funnel-shaped chamber and has a tangential component as well as a radial component with respect to the round or rounded inner shape.

15. Device according to claim 14, characterized in that, in the channel outlet direction, the tangential component is greater than the radial component, wherein the radial component is in particular zero.

16. Device according to claim 13 or 14, characterized in that the channel outlet direction of the channel section (K3) with respect to the funnel-shaped chamber is directed towards the funnel outlet or towards the tapered end of the funnel. is inclined downwards or has an axial component with respect to the rounded inner shape, which is directed towards the first channel section (K1 ).

17. Device according to one of claims 2 to 16, characterized in that the second channel section (K2), which can be brought into fluid contact with the vacuum pump (VP), has a further or second channel constriction (KE2).

18. Device according to one of claims 3 to 17, characterized in that a further or second vacuum pump valve (W2) arranged in the second channel section (K2) is arranged between the branching area (VB) and the further or second channel constriction (KE2).

19. Device according to one of claims 3 to 18, characterized in that a further or third vacuum pump valve (W3) arranged in the second channel section (K2) is arranged between the further or second channel constriction (KE2) and the vacuum pump (VP).

20. Device according to one of claims 2 to 19, characterized in that at least a partial area of ​​the inner wall of the branching region (VB) is thermally connected to a coolant.

21. Device according to one of claims 1 to 20, characterized in that a vacuum tank (VT) is arranged in the fluid connection between the first valve (V1) and the vacuum pump (VP).

22. Device according to claim 20, characterized in that the vacuum tank volume (VTV) of the vacuum tank (VT) is a multiple of the process chamber volume (PKV) of the process chamber (PK1 , PK2, PK3).

23. Device according to claim 22, characterized in that the ratio VTV / PKV of vacuum tank volume (VTV) of the vacuum tank (VT) to process chamber volume (PKV) of the process chamber (PK1, PK2, PK3) within within a range of 5 to 200 (5 < VTV / PKV < 200) and preferably within a range of 10 to 200 (10 < VTV / PKV < 200).

24. Device according to claim 22 or 23, characterized in that the ratio VTV / FPKV of vacuum tank volume (VTV) of the vacuum tank (VT) to free process chamber volume (FPKV) of the process chamber (PK1 , PK2, PK3) above the solvent (LM) is within a range of 10 to 400 (10 < VTV / FPKV < 400) and preferably within a range of 10 to 300 (10 < VTV / FPKV < 300) and most preferably in the range of 10 to 200 (10 < VTV / FPKV < 200).

25. Device according to one of claims 1 to 24, characterized in that an ultrasound source (US, US1, US2, US3) can be assigned to a process chamber (PK1, PK2, PK3), or that an ultrasound source (US, US1, US2, US3) is assigned to a process chamber (PK1, PK2, PK3) in a processing position.

26. Device according to claim 25, characterized in that a respective process chamber (PK1 , PK2, PK3) is assigned a respective ultrasound source (US1 , US2, US3), wherein preferably each ultrasound source generates a different ultrasound frequency or a different group or combination of ultrasound frequencies.

27. Device according to one of claims 1 to 26, characterized in that the process chamber (PK1 , PK2, PK3), into which the workpiece to be treated can be placed, has a means for moving the placed workpiece relative to the process chamber and relative to the solvent (LM).

28. Device according to one of claims 1 to 27, characterized in that the device has a drying fan (TV) which can be brought into fluid contact with the process chamber (PK1 , PK2, PK3) for drying the process chamber and a treated workpiece contained therein.

29. Device according to claim 28, characterized in that the drying fan (TV) and the process chamber (PK1, PK2, PK3) are contained in the A second valve (V2) is arranged in the fluid connection, wherein preferably an air filter (LV) is arranged upstream of the drying fan (TV) and preferably a heating unit (HE) for the drying air is arranged downstream of the drying fan (TV).

30. Device according to one of claims 1 to 29, characterized in that the device has several process chambers (PK1 , PK2, PK3), in particular at least three process chambers.

31. Device according to claim 30, characterized in that the device has a positioning unit (PE) on which the several process chambers (PK1, PK2, PK3) are fixed side by side, wherein the positioning unit can position one of the process chambers in a processing position within the device (rotation, translation).

32. Device according to any one of claims 1 to 31, characterized in that the device has a receiving unit (AE) for a workpiece to be treated, wherein the receiving unit (AE) is movable relative to a process chamber (PK1, PK2, PK3). (- cage and / or basket) 33. Device according to claim 32, characterized in that the device has a translation unit (TE) by means of which the receiving unit (AE) can be moved into and out of a process chamber (PK1 , PK2, PK3).

34. Device according to one of claims 1 to 33, characterized in that the vacuum tank (VT) is assembled from several vacuum tank components and can be reversibly disassembled, wherein the assembled vacuum tank (VT) has sealing means at least in contact areas of the vacuum tank wall sections of adjacent vacuum tank components, which are clamped between adjacent vacuum tank components.

35. Device according to one of claims 1 to 34, characterized in that the device has a control unit by means of which at least one The following elements can be controlled: - first valve (V1) - second valve (V2) - Closure unit (VE) - Vacuum pump (VP) - Ultrasound source (US, US1, US2, US3) - Drying fan (TV) - Positioning unit (PE) - Translation unit (TU) - Unit of rotation (RE) - Heating unit (HE) for drying air - Heating unit (HU) for process chamber 36. A method for treating workpieces, in particular for surface treatment of workpieces, and in particular using a device (1) according to any one of claims 1 to 35, wherein the method comprises the following steps: a) placing a workpiece to be treated into a receiving unit (AE); b) inserting the receiving unit (AE) with the workpiece to be treated into a process chamber (PK1, PK2, PK3); c) filling the process chamber (PK1, PK2, PK3) with at least one solvent (LM) up to a fill level corresponding to a partial filling of the process chamber with solvent (LM); d) hermetically sealing the process chamber (PK1, PK2, PK3) by means of a sealing unit (VE), which is in particular attached to the receiving unit (AE); e) evacuating the process chamber (PK1, PK2, PK3) by means of a vacuum pump (VP); h) Removal of solvent (LM) from the process chamber (PK1, PK2, PK3) and from the treated workpiece;i) Opening the process chamber (PK1, PK2, PK3) using the closure unit (VE); j) Moving the receiving unit (AE) with the treated workpiece out of the process chamber (PK1, PK2, PK3); k) Removing the treated workpiece from the receiving unit (AE).

37. Method for treating workpieces, in particular for surface treatment of workpieces, and in particular using a device (1) according to any one of claims 21 to 35, wherein the method comprises the following steps: a) placing a workpiece to be treated into a receiving unit (AE); b) inserting the receiving unit (AE) with the workpiece to be treated into a process chamber (PK1, PK2, PK3); c) filling the process chamber (PK1, PK2, PK3) with at least one solvent (LM) up to a fill level corresponding to a partial filling of the process chamber with solvent (LM); d) hermetically sealing the process chamber (PK1, PK2, PK3) by means of a sealing unit (VE), which is in particular attached to the receiving unit (AE); e*) evacuating a vacuum tank (VT) by means of a vacuum pump (VP);f1) Establishing a first fluid connection between a location above the fill level of the solvent-filled (LM) process chamber (PK1, PK2, PK3) and the vacuum tank (VT) by opening a first valve (V1); g1) Blocking the first fluid connection by closing the first valve (V1); f2) Establishing a second fluid connection between a location above the fill level of the solvent-filled (LM) process chamber (PK1, PK2, PK3) and the atmosphere by opening a second valve (V2); g2) Blocking the second fluid connection by closing the second valve (V2); h) Removing solvent (LM) from the process chamber (PK1, PK2, PK3) and from the treated workpiece; i) Opening the process chamber (PK1, PK2, PK3) by means of the closure unit (VE); j) Removal of the receiving unit (RU) with the treated workpiece from the process chamber (PK1, PK2, PK3); k) Removal of the treated workpiece from the receiving unit (RU).

38. Method according to claim 37, characterized in that after opening the first valve (V1 ) in step f1 ), the closing of the first valve (V1 ) in step g1 ) occurs before more than 1 / 10, preferably more than 1 / 100, of the volume of solvent (LM) has passed through the first valve (V1 ). (- by foam sensor and / or by keeping the valve open for a sufficiently short time between step f1 ) and g1 )) 39. Method according to one of claims 36 to 38, characterized in that during at least one of steps c) to h) ultrasound is introduced into the solvent (LM) from an ultrasound source (US, US1 , US2, US3).

40. Method according to one of claims 36 to 39, characterized in that before step f1 ) ultrasound is introduced into the solvent (LM) from an ultrasound source (US, US1 , US2, US3).

41. Method according to one of claims 36 to 40, characterized in that during at least one of steps c) to h) the workpiece introduced is moved relative to the process chamber and relative to the solvent (LM).

42. A method according to any one of claims 36 to 41, characterized in that the removal of solvent (LM) from the process chamber (PK1, PK2, PK3) and from the treated workpiece in step h) comprises rotating the receiving unit (AE) with the cleaned workpiece, wherein the receiving unit is rotated about a rotational axis by means of a rotation unit (RE). (- Centrifugal) 43. Method according to one of claims 36 to 42, characterized in that the removal of solvent (LM) from the process chamber (PK1 , PK2, PK3) and from the treated workpiece in step h) comprises drying the cleaned workpiece in the process chamber (PK1 , PK2, PK3) by means of a drying fan (TV), wherein a heating unit (HE) for the drying air is preferably arranged between the drying fan and the respective process chamber (PK1 , PK2, PK3).

44. Method according to one of claims 37 to 43, characterized in that the sequence of steps e*), f1 ), g1 ), f2), g2) is repeated several times in one of the process chambers (PK1 , PK2, PK3).

45. Method according to one of claims 37 to 44, characterized in that the evacuation step e*) continues continuously while the sequence of steps f1 ), g1 ), f2), g2) is repeated several times in one of the process chambers (PK1 , PK2, PK3).

46. ​​Method according to one of claims 36 to 45, characterized in that the sequence of steps b) to j) is carried out several times and each time in different process chambers (PK1 , PK2, PK3).

47. Method according to one of claims 37 to 46, characterized in that after drying and heating the treated workpiece in a process chamber (PK1 , PK2, PK3) steps e*) and f1 ) are carried out again.

48. Method according to claim 47, characterized in that the sequence of steps f1 ), g1 ), f2) and g2) is repeated several times.

49. Method according to one of claims 37 to 48, characterized in that, when establishing the first fluid connection by opening the first valve (V1) in step f1), a pressure drop Ap occurs at the location above the fill level of the solvent-filled process chamber (PK1, PK2, PK3) during a time period At, from an initial pressure p1 to a final pressure p2, wherein the initial pressure p1 is between 0.9 bar and 1.1 bar (0.9 bar < p1 < 1.1 bar), the final pressure p2 is between 0.01 bar and 0.3 bar (0.01 bar < p2 < 0.3 bar), and the time period At is in the range of 50 ms to 200 ms (50 ms < At < 200 ms).

50. Method according to one of claims 36 to 49, characterized in that the solvent (LM) has a temperature in the range of 10°C to 70°C and preferably in the range of 20°C to 50°C.

51. Method according to one of claims 36 to 50, characterized in that the treatment comprises passivation of the surface of the workpiece.

52. Method according to one of claims 36 to 51, characterized in that the treatment comprises cleaning the surface of the workpiece.

53. Method according to claim 51 or 52, characterized in that the treatment comprises cleaning the surface of the workpiece and passivating the surface of the workpiece.

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