EP0193147A2 - Press for extracting water from textiles - Google Patents

Abstract

In a machine frame (30), the dewatering press (20) has a press base (42) with drainage openings (43), a circular-cylindrical filling frame (45) with open ends on both sides and a plunger (60). The filling frame (45) and the plunger (60) are guided on common guides (48, 49) so as to be vertically displaceable and height-adjustable by means of a lifting device (50; 63). The plunger (60) has a rigid piston body (67) and a cup membrane (68) enveloping it from below. In the idle state, the outside diameter of the plunger (60) is smaller than the inside width of the filler frame (45). During the pressing operation, the plunger (60) plunges into the filling frame (45). When a pressure fluid is filled on the inside of the pot membrane (68), it lies on the circumference of the filling frame (45) and expands on the end face to the laundry cake (23) located underneath and presses it out. After pressing, the pot membrane (68) is relieved, pulling back in the radial direction from the filler frame (45), and then first the filler frame (45) and then also the plunger (60), so that the laundry cake (23) is exposed .

Description

Textiles that come freshly washed out of an automatically working and automatically unloading washing machine still contain a considerable amount of water from the last washing or rinsing process. This must be removed beforehand before the textiles can go to further processing stations, e.g. Dryers and / or deficiency stations can be forwarded. Dewatering presses are mostly used to dewater these textiles.

A known dewatering press (DE-PS 28 52 923) has a press table with a perforated plate and a collecting basket or filling frame in the form of a circular cylinder which is open on both sides. This filler frame is guided on a vertically aligned guide and is moved to different height positions by means of a lifting device. The filler frame has the same floor plan with a clear width that is slightly larger than the outer dimensions of the press table. The filler frame can therefore be placed over the press table and lowered relative to it until its upper edge is approximately at the same height as the top of the press table. The filler frame is provided with an outwardly projecting collar on its upper edge, the upper end surface of which is turned away from the filler frame is frustoconical, with an obtuse cone angle. On the underside, the collar has a flat end face as a contact surface with which the feed frame in its lowered position is supported on a support plate which surrounds the press table in a ring. The dewatering press also has a plunger which is also guided on a vertical guide in the line of alignment of the filler frame and can be moved to different height positions by means of a suitable lifting device. This plunger has a rigid piston body in the form of a bell open at the bottom, the opening of which is closed by a rubber-elastic membrane. The rim of the bell has the same projection as the collar of the filler frame and is frustoconical in the same way

The edge of the membrane lies against this edge of the bell and is connected there to the piston body by means of a metal clamping ring.

For draining textiles, the loading frame is brought into a height position in which its upper edge is so far above the press table that its lower edge just barely extends below the upper edge of the press table. When the plunger is raised, the wet textiles are introduced into the filling frame via a slide, so to speak washed in. The free water between the textiles runs through the drain openings in the press table and through the annular gap between the press table and the filling frame. The plunger is lowered with its lacquer edge onto the collar of the filler frame

Since this dewatering press works just as automatically as the upstream washing machine, it can easily happen that during this lowering movement, textile parts that were left on the relatively weakly inclined collar of the filler frame afterwards, subsequently between the metal collar of the filler frame and the metal clamping ring on the plunger trapped and at least wrinkled if not damaged.

After placing the rim of the bell on the collar of the filler frame, both parts are further lowered together relative to the press table until the collar sits on the support plate. In this height position, the upper edge of the filler frame is approximately at the level of the upper edge of the press sleeve. During this lowering movement, the textiles are held back by the press table. The membrane rests on the laundry cake and is first expanded into the interior of the bell-shaped piston body. A pressure fluid is pressed into the space between the membrane and the bell bottom, whereby the membrane compresses the laundry cake on the press table and the water largely from the laundry cake presses out, which then runs through the drain openings in the press table.

After the pressing process, the plunger is raised. So that the pressed laundry cake can be pushed sideways away from the press table, the loading frame must also be raised beforehand. However, since the laundry cake was not only compressed in height by the pressing process, but was also expanded towards the outside, the laundry cake lies against the inner wall of the filling frame with a considerable spreading force. The laundry cake is often lifted when the loading frame is lifted. It can then only be removed from the filling frame with great difficulty. Since the dewatering press is part of a fully automatic car wash, this behavior of the laundry cake means that the automatic workflow is very often disrupted. The operating personnel must then intervene by hand to restart the workflow.

Another known dewatering press has a press base that is perforated. A filling frame in the form of a circular cylinder section which is open on both sides is arranged above this pressing floor, which is guided displaceably on a vertically aligned guide and which can be lowered onto the pressing floor by means of a lifting device and adjusted to different height positions. In the line of alignment of the filler frame, a plunger is adjustable in height by means of a piston drive with a vertical movement path. The plunger has a rigid piston plate, on the underside of which a press pad or press cushion is arranged, which has a circular-cylindrical edge part and a bottom part. The pressure pad is filled with a water pressure that is normally depressurized, the volume of which remains unchanged

At the start of the pressing process, the pressure pad is only partially immersed in the filling frame of this dewatering press. Due to the fact that the press cushion lies against the laundry cake, the internal pressure in the press cushion increases. As a result, the section of the edge part of the pressure pad that is still outside the filling frame is radially expanded. In the case of a laundry cake with a very different filling height, it may also happen that the pressure pad is pushed up on one side, so that the radial expansion is increased at this point. As a result of this one-sided warping of the press cushion, it can even happen that individual textile parts are pressed out on the raised side.

During the further downward movement of the press piston and the press cushion, the widened edge part of the press cushion, which is therefore seated on the edge of the filling frame, must be overcome by overcoming considerable frictional forces be radially compressed and at the same time pressed axially into the filler frame. Even if the edge part has completely entered the filler frame, this frictional force is retained when the plunger continues to descend, because ^* the internal pressure of the press cushion continues to act radially on the edge part.

With the frequently occurring uneven filling height of the material to be pressed, only the part with the larger filling height is correctly pressed out. The areas of the laundry cake with an initially lower filling height, on the other hand, are squeezed only inadequately.

In this press, the piston plate above the press cushion must be adapted to the inside width of the filler frame with a very close fit, so that when the press cushion is immersed in the filler frame, an annular gap does not remain between the latter and the edge of the piston plate, into which the edge part of the press cushion passes the high internal pressure could be pressed, which would be detrimental to the pressure pad, in particular its edge part. This close fit between the piston plate and the filler frame on the other hand has the major disadvantage that those items of laundry that accidentally remained on the edge of the filler frame or those at. Pressing process were pushed away to the edge area, are clamped between the metal piston plate and the metal filler frame and can even be sheared off.

The invention has for its object to provide a dewatering press for textiles with which a trouble-free automatic operation is possible with a good and as uniform a dewatering result as possible and with the greatest possible protection of the textiles.

This object is achieved with a dewatering press with the features specified in claim 1.

Characterized in that the piston with its membrane in the radial direction has a certain undersize compared to the filler frame, the piston can be inserted into the filler frame without the occurrence of frictional forces until it has reached the height position corresponding to its pressing position, in which it is subsequently held. Characterized in that the piston is also surrounded on its circumferential surface by the membrane, ie by its collar part, which has the same elastic compliance as the bottom part, this outer skin of the piston can radially when a pressure medium is applied to the space between it and the piston body stretch until it comes to rest on the filling frame. From this operating state on, the press space between the press base, the filling frame and the piston is sealed off from the outside and above, so that the water squeezed out of the textiles can only escape downward through the outlet openings of the press base. Characterized in that the membrane is freely movable outside of its attachment bead relative to the piston body, it can move away from the piston body towards the textiles lying below it when subjected to an overpressure on its inside and press it against the press base with uniform contact pressure everywhere. As a result of this free expansion possibility, the membrane can fill the entire cavity of the filler frame even when only a few textiles are present. This also applies to an uneven filling of the filling frame with a very different filling height of the textiles. Even then, the squeeze result is largely independent of the filling quantity and the filling height at every point on the floor. Characterized in that the collar part of the membrane has a clear width _' which is slightly larger than the diameter of the circumferential surface of the piston body and in that the end face of the piston body is at least partially hollow with respect to a reference plane adjacent to it, when in the space between the membrane and a negative pressure is generated to the piston body in relation to the ambient pressure, the bottom part of the membrane is drawn into the cavity of the end face of the piston body and at the same time the collar part of the membrane is reduced in its outer diameter and placed on the peripheral surface of the piston body. At the same time, the collar part of the membrane is lifted inwards from the inner surface of the wall of the filler frame. This in turn allows the filler frame to be raised relative to the piston which is still held in its pressed position without any frictional forces occurring between the piston and the filler frame. During this lifting of the filling frame, the laundry cake is held back by the piston if it should ever rest against the inner wall of the filling frame as a result of the pressing process. When the plunger has also subsequently been raised, the laundry cake is freely accessible on the press base and can then easily be conveyed further by means of a slide.

If any textile parts are left on the edge of the filler frame and partially hang into the interior of the filler frame, as a result of which they can get between the circumferential wall of the piston and the filler frame, then when the piston is immersed in the filler frame, these parts become at most between the metal one Filling frame and the rubber-elastic collar part of the membrane pressed together during the subsequent pressing process and drained. Because of the flexibility of the outer skin of the piston, these textile parts do not suffer any damage.

The undersize between the peripheral wall of the piston body and the inside width of the collar part of the membrane makes it easier to pull the membrane open, in particular to slip the fastening bead over the peripheral surface of the piston body. In addition, the fastening bead can thereby have a greater radial extension, which benefits a greater radial elasticity of the collar part of the membrane, which in turn improves the sealing effect of the collar part towards the top.

In one embodiment of the drainage press according to claim 2 it is achieved that when the inside of the membrane is subjected to an overpressure in which its collar part is pressed outwards, the wedge-shaped cross-sectional shape of the fastening bead, the sealing effect between the fastening bead and the adjacent parts of the Piston, body is improved. As a result, the elastic cross-sectional reductions in the fastening bead are compensated for without any leakages and thus pressure losses of the pressure medium being feared.

In one embodiment of the dewatering press according to claim 3 it is achieved that the lifting device for the plunger is relieved of the considerable reaction forces that occur during the pressing process between the membrane supported on the press base on the one hand and the piston body on the other. These reaction forces are transmitted directly from the locking device to the machine frame. This allows the lifting device with a significantly lower pressure Pressure medium are operated. For all these reasons, the lifting device as well as the parts interacting with it can be built considerably lighter and therefore also considerably cheaper.

A design of the dewatering press according to claim 4 creates a digital pressure regeneration for certain pressure levels of the working medium in the cavity on the inside of the membrane. With their help, the baling pressure can be set to the maximum value that is tolerable for different textiles and can be maintained very reliably. By means of the vibrator, the comparison circuit is connected to the pressure sensor on the one hand and the selection device on the other hand at regular small intervals and the actual pressure measured by the pressure sensor is compared with the set pressure set on the selection device and when the set pressure is exceeded the actual pressure is changed to the desired pressure value by at Bypass of the existing solenoid valves that valve or that group of several valves is opened briefly, the throttle point alone or together causes the pressure drop required to bring the pressure in the connecting line and in the interior of the membrane to the set pressure and keep it there.

In an embodiment of the dewatering press according to claim 5, the squeezed laundry cake can be gently pushed out of the area of the press, taking up the least possible space, and moved to a conveyor system for further conveyance to subsequent treatment stations. The shifting speed and the shifting force can be adjusted very easily to the requirements of the laundry cake and the individual laundry items via the working pressure of the .works above the pneumatic piston drives.

• Fig. ₁ Einen Vertikalschnitt der Entwässerungspresse in Längsrichtung, in einem ersten Betriebszustand der Teile;
• Fig. 2 einen Vertikalschnitt der Entwässerungspresse in Querrichtung, im ersten Betriebszustand der Teile;
• Fig. 3 einen Vertikalschnitt wie Fig. 1 in einem zweiten Betriebszustand;
• Fig. 4 einen Vertikalschnitt wie Fig. 2 im zweiten Betriebszustand;
• Fig. 5 einen Vertikalschnitt wie Fig. 2 in einem dritten Betriebszustand;
• Fig. 6 einen Vertikalschnitt wie Fig. 2 in einem vierten Betriebszustand;
• Fig. 7 einen Vertikalschnitt wie Fig. 2 in einem fünften Betriebszustand;
• Fig. 8 einen Vertikalschnitt wie Fig. ₁ im fünften Betriebszustand;
• Fig. 9 einen Vertikalschnitt wie Fig. 1 in einem sechsten Betriebszustand;
• Fig. ₁0 einen Vertikalschnitt wie Fig. 1 in einem siebten Betriebszustand;
• Fig. 11 einen ausschnittweise dargestellten Querschnitt einiger Teile der Entwässerungspresse im Ruhezustand;
• Fig. 12 einen Querschnitt wie Fig. 11 in einem ersten Betriebszustand:
• Fig. 13 einen Querschnitt wie Fig. 11 in einem zweiten Betriebszustand.
• Fig. 14 ein ausschnittweise dargestellter Vertikalschnitt der Entwässerungspresse mit Einzelheiten einer Druckregelung und eines Schiebers;
• Fig. 15 einen Horizontalschnitt der Entwässerungspresse nach Fig. 14;
• Fig. 16 eine teilweise geschnittene dargestellte Draufsicht eines Teils der Druckregelung der Entwässerungspresse;
• Fig. 17 eine teilweise geschnittene dargestellte Stirnansicht des Teils der Druckregelung nach Fig. 16.

The invention is explained in more detail below on the basis of an exemplary embodiment shown in the drawing, in which:

• _{1 shows} a vertical section of the dewatering press in the longitudinal direction, in a first operating state of the parts;
• 2 shows a vertical section of the dewatering press in the transverse direction, in the first operating state of the parts;
• 3 shows a vertical section like FIG. 1 in a second operating state;
• 4 shows a vertical section like FIG. 2 in the second operating state;
• 5 shows a vertical section like FIG. 2 in a third operating state;
• 6 shows a vertical section like FIG. 2 in a fourth operating state;
• 7 shows a vertical section like FIG. 2 in a fifth operating state;
• 8 shows a vertical section like FIG. ₁ in the fifth operating state;
• 9 shows a vertical section like FIG. 1 in a sixth operating state;
• Fig. ₁ is a vertical section 0 as shown in Fig 1 in a seventh operation state.
• 11 shows a cross-section, shown in detail, of some parts of the dewatering press in the idle state;
• 12 shows a cross section like FIG. 11 in a first operating state:
• 13 shows a cross section like FIG. 11 in a second operating state.
• Fig. 14 is a fragmentary vertical section of the dewatering press with details of a pressure control and a slide;
• 15 shows a horizontal section of the dewatering press according to FIG. 14;
• 16 is a partially sectioned top view of part of the pressure control of the dewatering press;
• FIG. 17 shows a partially sectioned end view of the part of the pressure control according to FIG. 16.

1 and 2, an automatically operating dewatering press 20 can be seen, which is set up following a fully automatic washing machine 21 (only FIG. 1). The laundry is removed from the washing machine 21 from its outlet nozzle 22 in the form of an initially very loose laundry cake 23 issued, and to a certain extent washed out, and guided via a guide trough 24 to the dewatering press 20. In the guide trough 24, the actual trough part 25 is closed by a funnel part 26, the walls of which, however, are largely circular-cylindrical. The laundry cake 23 is later, after dewatering by the dewatering press, pushed by means of a slide 27 onto a conveyor belt 28 adjoining the dewatering press 20 (FIG. 10) and conveyed by this to further processing stations such as washer dryers, lack machines and the like.

The dewatering press 20 has a machine frame 30 which is composed of four disk-shaped yoke frames 31 ... 34. Each of these yoke frames is composed of a foot 35, two side walls 36 and 37 and a yoke 38 which are firmly combined to form the closed yoke frame - (Fig. 2). The yoke frames are inseparably joined together in the area of their foot by means of three continuous foot bridges 39 and in the area of their yokes by three groups of four yoke bars 41 each to form machine frame 30, namely welded together

On the feet 35 of the four yoke frames 31 ... 34 rests a press base 42, which is provided with numerous drain openings 43, through which the water emerging from the laundry cake 23 can get into the collecting container 44 arranged below the press base 42. This collecting container 44 also surrounds the feet 35 of the yoke frame 31 .... 3 ₄ .

A circular cylindrical filler frame 45 is arranged in the interior of the machine frame 30. It is open on both ends and has a smooth inner wall of a certain clear width. It is connected in the space between the two middle yoke frames 32 and 33, each with a guide arm 46 or 47, by means of which it is guided on a guide column ₄ 8 or ₄ 9 in the vertical direction

A lifting device 50 with two piston drives 51 and 52 is provided for the height adjustment of the filling frame 45. Your working cylinders 53 and 54 are detachably attached to the adjacent yoke frames 32 and 33. Your piston rod 55 and 56 is connected to the guide arm 46 and 47 of the filler frame 45. By means of this lifting device 50, the loading frame 45 can be lowered onto the press base 41 (FIGS. 1 ... 6) or raised to a certain height position (FIGS. 7 ... 10).

In the interior of the machine frame 30, a plunger 60 is arranged on a carrier plate 57 by means of a plurality of spacers 58. The carrier plate 57 is guided by means of two guide arms 61 and 62 on the same guide columns 48 and 49, on which the filling frame 45 is also guided by means of the guide arms 46 and 47. So that the plunger is slidably guided in the line of alignment of the feed frame 45. A separate lifting device 63 is provided for the plunger 60, which is designed as a pneumatically operating piston drive 64. Its working cylinder sits on the yokes 38 of the two middle yoke frames 32 and 33 and on the two yoke webs 61 in the middle and is detachably connected to these parts. The piston rod 66 is connected to the carrier plate 57.

The plunger 60 is constructed in several parts. It has a rigid piston body 67 made of metal, a rubber-elastic cup membrane 68 and a rigid clamping ring 69 made of metal. In Fig. 11, in which the pot membrane 68 is shown in a de-energized state, as it arises in the manufacturing mold, the parts of the plunger 60 can be clearly seen in their geometric shape and in their mutual association.

The pot membrane 68 is made of a highly elastic material, for. B. made of an alkali-resistant synthetic rubber. It has a flat bottom part 61 and a circular-cylindrical collar part 72, which connect seamlessly to one another, the cross-sectional profile at the transition point 73 being rounded in an arc. The bottom part 71 and the collar part 72, like the transition point 73, have an at least approximately uniform wall thickness. A radially inwardly directed fastening bead 75 is formed on the free edge 54 of the collar part 72, with which the pot membrane 68 is clamped on the piston body 67 by means of the clamping ring 69 and at the same time is fastened in a fluid-tight manner. The attachment bead 75 has a symmetrical trapezoidal or dovetail cross-sectional shape, the height of which increases from the outer edge to the inner edge.

In the de-energized state (FIG. 11), the collar part 72 of the pot membrane 68 has an outside diameter that is a certain amount "u" smaller than the inside width of the filler frame 45. The piston body 67 has a peripheral surface 76, the axial height of which is smaller by the dimension “v” than the clear height of the collar part 72 between the base part 71 and the fastening bead 75. The peripheral surface 76 of the piston body 67 is a conical surface. Its largest diameter, even at the transition point of the collar part 72 to the fastening bead 75, is at most equal to the clear width of the collar part 72, which is measured in the same cross-sectional plane. It is expediently even a little smaller so that the fastening bead 75 can be put over it more easily. From this point, the undersize of the outer diameter of the circumferential surface 76 increases steadily compared to the inside width of the collar part 72 up to a maximum value "w" in the region of the rounded piston edge 77.

The end face 78 of the piston body 67 is hollow compared to a reference plane 79, which abuts the circumferential piston edge 77, in such a way that from the rounded piston edge 77 to the center line 80 its distance from this reference plane 79 increases continuously to a maximum value , the center line 80 of the surface normal of the end face 78 being aligned parallel to the center line 80.

The piston body 67 is provided with at least one axial through hole 81, the mouth 82 of which is located in the end face 78. On the outside of the piston body 67, a connecting line 83 (FIG. 1) (not shown in FIG. 1) of a filling and emptying device 84 is connected to the through hole 81. This includes, among other things, a feed pump 85 with a large delivery volume for filling and emptying the space between the piston body 67 and the cup membrane 68 of the plunger 60 and a pressure pump 86 for generating a high overpressure in this space of the plunger 60. The suction line 87 of both pumps is connected to the collecting tank 4 ₄ for the drain water, which is thus initially used for the operation of the dewatering press. before the waa. sh and rinsing in the washing machine 21 is fed again.

On the piston body 67 on the side facing away from the end face 78 there is a support surface 88 (FIG. 12) which is matched to the cross-sectional shape of the tension-free fastening bead 75. On the clamping ring 69 there is also a support surface 89 on the side facing the fastening bead 75, which is matched to the cross-sectional shape of the fastening bead. On the clamping ring 69 adjoins this support surface 89 in the radial direction towards the outside, a support edge 91 which is matched to the cross-sectional shape of the edge 7 ₄ of the collar part 72 in order to support the collar part 72 in the axial direction. The outer diameter of the support edge 9 ₁ is a certain amount "x" smaller than the inside width of the filler frame 45. This undersize "x" is expediently chosen to be somewhat larger than the undersize "u" of the tension-free collar part 72 relative to the filler frame 45, and thus textile parts , which happen to get into the annular gap between the filler frame 45 and the plunger 60, are not squeezed between the metal filler frame 45 and the metal clamping ring 69.

A locking device 92 is provided for the plunger 60, which locks it in its operating position (FIGS. 5 and 6) with respect to the machine frame 30, so that its lifting device 63 is relieved of the axial pressing forces. To the locking device 92 include two bolts 93 and 94 which are guided on the top of the carrier plate 57 in the radial direction and which are coupled to a piston drive 95 in such a way that the working cylinder 96 with a bolt 94 and the piston rod 97 with the other bolt 93 are connected. As further parts of the locking device 92 are on the machine frame 30, namely on the two cheek parts 36 and 37, a shoulder 98 and 99, respectively, which are matched to the bolts 93 and 94 so that the bolts in the operating position of the plunger 60 93 and 94 can be pushed by their piston drive 95 under paragraphs 98 and 99 (Fig. 5 and 6). As a result, the reaction forces of the plunger 60 can then be supported directly on the machine frame 30 via the carrier plate 57 and the latches 93 and 94.

The operation of the dewatering press is explained below.

When the feed frame 45 is lowered and the plunger 60 is raised (FIGS. 1 and 2), the washing machine 21 transfers a batch of laundry via the guide channel 24 into the feed frame ₄ 5. Since the laundry is still mixed with a lot of water from the last rinse, it is virtually washed into the filler frame 45. The frictional forces within such a laundry cake 23 vary in size depending on the type of textiles. In the case of textiles made of plastic fibers, the internal friction is relatively low, which is why such a laundry cake is distributed relatively evenly in the filling frame 45. In the case of textiles made of cotton or with a high proportion of cotton, the internal friction in the laundry cake is relatively large. In such textiles there is therefore always a tendency for the laundry cake 23 to pile up on the wall of the filling frame 45 opposite the guide trough 24 (FIG. 3). Since the textiles are generally washed out of the running movement of the drum of the washing machine 21 with a certain twist onto the guide trough 24 and from there into the filling frame 45, the laundry cake 23 in the filling frame 54 is generally also piled up on one side transversely to its direction of insertion ( Fig. 4). In the case of very lubricious textiles, this difference in height usually compensates somewhat. In the case of less slippery textiles, the laundry cake 23 remains in the filling frame 45 in this double-sided arrangement.

During the washing in and during the first period of storage of the laundry cake 23 in the filling frame 45, a large part of the water carried is already running through the drain openings in the press base 42 into the collecting container 44 (FIG. 4). By means of the lifting device 63, the carrier plate 57 is lowered on the guide columns 48 and 49 into the operating position or pressing position. The plunger 60 is immersed in the filler frame ₄₅ to a certain depth (Fig.

5). Insofar as the laundry cake 23 previously protruded further, it is compressed to this immersion depth on the end face 78 of the piston body 67. As a result, a further part of the water is pressed out of the press cake 23 When the plunger 60 is immersed in the filler frame ₄ 5, there is a sufficiently wide annular gap between these two parts which prevents such textile parts from being pinched or even squeezed between these two parts. that got stuck on the edge of the filling frame 45 or that were pushed up slightly during the plunging movement of the plunger 60 between the latter and the filling frame, as is indicated in FIG. 5 on the right-hand side

When the carrier plate 57 with the plunger 60 has reached the operating position or the press position (FIG. 5), the two bolts 93 and 94 are moved radially outward into their bolt position by means of the transverse piston drive 95, in which they are placed under the shoulders 98 and 99 on the machine frame 30 grab (Fig. 6) and thus lock the support plate 50 with the plunger 60 in the vertical direction. From the two pumps 85 and 86 working in parallel, water is pressed as pressure medium into the space between the piston body 67 and the cup membrane 68 via the connecting line 83.As a result, the collar part 72 of the cup membrane 68, starting from the fastening bead 75, lies against the inner wall of the filler frame 45 seals the annular gap between the plunger 60 and the filling frame ₄ 5 upwards (Fig. 13). To the extent that the fastening bead 75 is pulled outward and stretched radially, the wedge shape or dovetail shape of its cross section resembles this elastic deformation without. With the increasing filling process of the interior of the pot membrane 68, its bottom part 71 is pressed increasingly downwards against the laundry cake 23, whereby, of course, the support on those parts of the laundry cake 23 that were closest to the unexpanded membrane takes place first. During this expansion movement of the pot membrane 68, all parts of the laundry cake 23 are finally reached as the filling process progresses (FIG. 6).

When the filling process is largely completed, the feed pump 85 is switched off and the pressure pump 86 continues to work alone. This then only conveys a smaller amount of pressure medium with a pressure of approx. 40 bar. Under this very high pressure, which acts in full on the laundry cake 23 due to the high elasticity of the pot membrane 68, the remaining water in the laundry cake is largely pressed out of it, whereby it runs through the outlet openings in the pressing base 42 into the collecting container 44.

When the laundry cake 23 has been squeezed out sufficiently, the pressure pump 86 is switched off and the feed pump 85 is switched on with the feed direction reversed to empty the cavity of the piston. As the pressure medium is conveyed out of the cavity of the piston, the pot membrane 68 contracts more and more. Her collar part 72 withdraws from the filler frame 45 so that an annular gap is again free between the plunger 60 and the filler frame 45. The bottom part 71 of the pot membrane is then still in contact with the pressed laundry cake 23, namely on the parts which protrude the highest, and increasingly withdraws more from the laundry cake 23 as the emptying process progresses.

As soon as the collar part 72 of the pot membrane has withdrawn sufficiently far from the filler frame 45, the filler frame _{45 is} raised to its highest height position by means of the piston drives ₅₁ and 52 on the guide columns 48 and 49 (FIG. 7), in which it is just below the carrier plate 57 stands or at most bears against this. During this lifting movement of the feed frame 45, the plunger 60 remains in its operating position.

It serves as a hold-down device, which prevents the laundry cake 23 from being raised with the filling frame 45 if, depending on the original arrangement of the textile parts of the laundry cake 23 and depending on their mechanical behavior when pressed, some parts of the laundry cake 23 are more or less diametrically adjusted are pressed on the outside so that they lie relatively close to the filling frame 45 and as a result there is a certain adhesive force between the laundry cake 23 and the filling frame 45. From this sequence of movements of the filling frame 45 relative to the plunger 60, it becomes clear why the plunger 60 cannot be arranged directly on the guide plate 57, but must be arranged by means of the spacer 58 by this stroke of the filling frame 45.

At the latest when the filler frame 45 is fully raised, the function of the plunger 60 as a hold-down is not necessary. The space between the pot membrane 68 and the piston body 67 is not only completely emptied of the pressure medium. but even generated a negative pressure in the cavity by the feed pump 8. Due to the pressure difference, the cup membrane 68 is pressed against the outside of the piston body 67, as can be seen from FIG. 12.

• Aus Fig. 14 und 15 sind einige Einzelheiten des Schiebers 27 und seines Antriebes ersichtlich. Der Schieber 27 hat die Form einer Leiste mit trapezförmigem Seitenriß, dessen Parallelseiten parallel zum Pressenboden 40 ausgerichtet sind. Die dem Wäschekuchen 23 zugekehrte Wandfläche ist gegenüber der Lotrechten in Aufwärtsrichtung nach hinten leicht geneigt.

At the latest after the end of the lifting movement of the filling frame 45, the locking device 92 of the plunger 60 is released, the two bolts 93 and 94 being retracted from the locking position into their release position by means of the piston drive 95 (FIG. 7). By means of the lifting device 63, the carrier plate 57 with the plunger 60 is raised into its rest position or starting position (FIG. 9). The pressed laundry cake 23 is now exposed on the press base 42. It can now be pushed away from the press base 42 to the conveyor belt 28 by means of the slide 27 (FIG. 10) and can then be conveyed from there to the further processing stations:

• 14 and 15 show some details of the slide 27 and its drive. The slide 27 has the shape of a strip with a trapezoidal side tear, the parallel sides of which are aligned parallel to the press base 40. The wall surface facing the laundry cake 23 is slightly inclined rearwards in relation to the vertical in the upward direction.

Two pneumatic piston drives 101 and 102 are provided to drive the slide 27 and are arranged on the press base 42 within the yoke frames 31... 34 of the machine frame. They lie outside the installation area of the filler frame 45 indicated by a chain line in FIG. 15 and are aligned parallel to the direction of displacement of the slide 27.

The two piston drives 101 and 102 have no piston rod. Instead, the piston is connected to a piston bracket 103 or 10 ₄ , which protrudes laterally from the cylinder in the radial direction through a longitudinal slot (not shown) of the cylinder of the piston drive. This longitudinal slot is sealed by means of two sealing tapes. A coupling member 105 or 106 is expediently coupled to the piston bracket 103 and 104 in a manner which, if possible, transmits only those forces which are aligned parallel to the longitudinal axis of the piston drives 101 and 102, and the forces oriented transversely thereto, in particular perpendicular to the Press floor 28 aligned forces, avoided if possible. The coupling members 105 and 106 are firmly connected to the slide 27.

The two piston drives ₁ 0 ₁ and 102 are dimensioned so long that, on the one hand, they do not protrude beyond the base frame, on the one hand, that on the other hand the slide 27 in its rest position shown in dash-dotted lines in FIG. 15 and designated 27 'is sufficiently far outside the installation area of the filler frame 45 stands and that in its most displaced position, which was shown in FIG. 15 on the right, its front side extends as far as possible to the conveyor belt 28.

As soon as the laundry cake 23 is pushed down from the press base 42 and the slide 27 has returned to its starting position, the loading frame ₄ 5 is lowered again onto the press base 42 by means of the lifting device 50 with the two piston drives 51 and 52. The starting position of the parts according to FIGS. 1 and 2 is then given again, in which laundry can again be transferred from the washing machine 2 ₁ into the dewatering press 20.

In FIG. 14, a pressure control for the working pressure of the working medium is indicated, which is pressed into the space between the membrane 68 and the piston body 67 via the connecting line 83 (FIGS. 6 to 8 and FIG. 13). The pressure control 107 includes a pressure sensor 108 which is inserted into the connecting line 83 to the intermediate space of the membrane 68, which in this case has the function of the pressure line. A bypass 109 branches off from the connecting line 83 upstream of the pressure sensor 108 and opens into the reservoir 44 of the two pumps 85 and 86 or at least into the suction line of the pressure pump 86. The pressure control 107 also includes a control (not shown in detail) with a selection device for different pressure levels, with a vibrator and with a comparator circuit. As a further part of the pressure control, three solenoid valves 111 ... 113 are present in the bypass 109 (FIGS. 16 and 17). The three solenoid valves 111 ... 113 are connected in parallel to each other. Their from Fig. 16 to the solenoid valve ₁ 1 apparent inlet port 114 is connected to a common manifold body 115 which is connected to the connection line 83. The outlet opening ₁₁ 6 is connected to a common body ₁ 17 for all solenoid valves. The connection between each of the solenoid valves 111 ... 113 and the distributor body 115 is made via a banjo bolt 118, 119 or 120, which are inserted through a pair of aligned through holes in the collector body and screwed into the corresponding thread on the valve body of the solenoid valve . In the same way, the solenoid valves 111 ... 113 are each connected to the collecting body 117 by means of a hollow screw 121 or 122 or 123, which in turn is connected to the drain line from the bypass 109 to the reservoir 44.

. A throttle point 124 is arranged in front of the inlet opening 114 of each of the solenoid valves. This is formed by a throttle bore 125, with the cavity of the collector body connecting the inner cavity of the hollow screw 118 ₁ 15 °. This throttle bore ₁ 25 in the hollow screw 118 has a certain passage cross section. The throttle bore 126 in the hollow screw 119 has a different, namely a slightly larger passage cross section. The throttle bore 127 in the banjo bolt 120 also has a different, namely a slightly larger passage cross section than the other two throttle bores 125 and 126. The cross bore 128 is in the banjo bolts 121 ... 123 on the outlet side of the solenoid valves of the same size. Their passage cross section is at least equal to the largest passage cross section of the banjo bolts on the inlet side of the solenoid valves or even somewhat larger.

When the laundry press is operating, the pressure pump 86 driven by its drive motor at a constant speed delivers a maximum operating pressure of the working medium of, for example, 40 bar. If this highest operating pressure is too high for one or the other type of textile because it could become wrinkled and / or tissue breakage could occur, a lower pressure level is set on the selection device depending on the sensitivity of the textiles. The vibrator switches the signal output of the selection device and the signal output of the pressure sensor 108 to the comparator circuit at regular, very short time intervals, which generates an actuation signal for the solenoid valves 111 ... 113 from the two input signals. Depending on the level of the pressure level set on the selection circuit and the actual pressure in the connecting line 83, one or more of the solenoid valves is opened for a short period of time by the pressure control, so that a very specific pressure drop is generated at its throttle point, through which the pressure in the Connection line 83 is lowered to the desired pressure value and is kept at this pressure value. If the diameters of the throttle bores 125 ... 127 in the banjo bolts 118 ... 120 are stepped with 1.5 mm, 2.5 mm and 2.8 mm, for example, by switching on the solenoid valves in following numerical selection: 1, 2, 3, 1 + 2, 1 + 3, 2 + 3, and 1 + 2 + 3 following pressure levels with the pressure values 36 bar, 31 bar, 28 bar, 26 bar, 24 bar, 21 bar and 18 bar can be reached and maintained relatively accurately.

Instead of this digital pressure control, the pressure control of the medium can also be carried out with an analog pressure control valve. However, since intermediate values always have to be set carefully, experience has shown that this pressure control is somewhat more susceptible to faults.

Claims (5)

1. dewatering press for textiles, -with a press bottom with drain openings with a circular cylindrical filler frame which is open on both ends, which is guided displaceably on vertically aligned guides and which can be lowered onto the press base by means of a lifting device and raised to different height positions, -with a press piston, which has a circular, rigid piston body and a pot-shaped elastic body which is attached to it along an edge region and is filled with a liquid, which is displaceably guided in the alignment line of the filler frame by means of a vertically oriented guide and which can be moved to different height positions by means of a lifting device , characterized by the features: the elastic body is designed as a pot membrane (68), the flat base part (71) and the circular cylindrical collar part (72) of which are connected to one another without a transition, an inwardly directed fastening bead (75) is formed on the open edge (74) of the collar part (72), - On the side of the fastening bead (75) facing away from the bottom part (71) of the membrane (68) there is a clamping ring (69) which, in the axial direction, lies outside of its bearing surface (89) for the fastening bead (75) with the piston body (67) connected is, -The collar part (72) of the membrane (68) has an outer diameter when de-energized, which is a certain amount (u) smaller than the inside width of the filler frame (45), -on the piston body (67), the peripheral surface (76) between the front bearing surface (88) for the fastening bead (75) of the membrane (68) and its free end face - (78) is a certain amount (v) lower than the clear axial Distance between the bottom part (71) and the fastening bead (75) of the membrane (68), - the outer diameter of the peripheral surface (76) of the piston body (67) is a certain amount (w) smaller than the clear width measured in the same plane the collar part (72) of the membrane (68), the free end face (78) of the piston body (67) is at least partially hollow with respect to a reference plane (79) lying against it, -The space between the membrane (68) and the piston body (67) is connected to a filling and emptying device (84) with a feed pump (85) and a pressure pump (86). 2. Dewatering press according to claim 1, characterized by the features: the cross-sectional shape of the fastening bead (75) of the membrane (68) has a height increasing from the outer edge to the inner edge, preferably in the manner of a one-sided or double-sided dovetail, on the piston body (67) and on the clamping ring (69), the bearing surface (88, 89) for the fastening bead (75) are matched to its cross-sectional shape in the stress-free state, a support edge (91) for the edge (74) of the membrane (68) is preferably arranged, in particular integrally formed, on the clamping ring (69) and projects in the radial direction beyond the contact surface (89) for the fastening bead (75), the outside diameter of which however, is a certain amount (x) smaller than the inside width of the filler frame ( ₄₅ ). 3. Dewatering press according to claim 1 or 2. characterized by the feature: - There is a locking device (92), the parts (93, 94) of which are partly on the plunger (60) or a part (57) connected to it and partly on the machine frame (30) or a part connected to it - (36, 37 ) are arranged, by means of which the plunger (60) can be locked in its operating or pressing position. 4. Dewatering press according to one of claims 1 to 3, characterized by the features: a pressure sensor (108) is installed in the connecting line (83) between the pressure pump - (86) and the space between the diaphragm (68) and the piston body (67), which generates control signals dependent on the pressure in the connecting line 83, a bypass (109) is connected to the connecting line (83) and opens into the storage container ( ₄₄ ) in front of the pressure pump (86) or into its suction line, a number of solenoid valves (111 ... 113) are arranged in the bypass (109), their inlet opening (114) parallel to one another, preferably via a common distributor body (115), to the connecting line (83) and their outlet opening (116) parallel to one another , preferably via a common collecting body ( ₁₁ 7), is connected to the storage container (44) or the suction line, -In front of the inlet opening (114) of each solenoid valve - (111 ... 113) is a throttle point (124), preferably in the form of a throttle bore (125) in a hollow screw - (118 ... 120) or in the form of a the inlet orifice (114) inserted, which has a specific passage cross section that differs from the passage cross section of the other throttle points, There is a control with a selection device for different pressure levels, with a vibrator and with a comparator circuit, which contains both the control signals of the pressure sensor ( ₁ 08) and the setting signals the selection device processed to actuation signals for the solenoid valves (111 ... 113). 5. Dewatering press according to one of claims 1 to 4, with a slide which is displaceably guided on the press base from one side of the installation area of the feed frame to at least the opposite side and is coupled to a drive, characterized by the feature: the slide 27 each coupled with a rodless pneumatic piston drive ( ₁ 0 ₁ ; 102), which is arranged on both sides of the installation area of the filler frame (45) and aligned parallel to the displacement path of the slide (27).

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