EP2467602A2

EP2467602A2 - Rotary piston pump for metering a coating agent

Info

Publication number: EP2467602A2
Application number: EP10742744A
Authority: EP
Inventors: Frank Herre; Rainer Melcher; Manfred Michelfelder; Steffen Stotzny
Original assignee: Duerr Systems AG
Current assignee: Duerr Systems AG
Priority date: 2009-08-21
Filing date: 2010-08-02
Publication date: 2012-06-27
Anticipated expiration: 2030-08-02
Also published as: EP2467602B1; WO2011020552A3; DE102009038462A8; WO2011020552A2; JP2013502522A; ES2534837T3; US9140247B2; CN102498293B; JP5699148B2; CN102498293A; US20120186518A1; DE102009038462A1; PL2467602T3

Abstract

The invention relates to a rotary piston pump (1) for metering a coating agent in a coating installation, comprising several pump units (6-8), each having one cylinder (32) and one rotary piston (31) which carries out a tumbling action in the cylinder (32).

Description

DESCRIPTION Swashplate pump for dosing a coating agent

The invention relates to a wobble piston pump for metering a coating agent in a coating system. Such a wobble piston pump is known per se from EP 1 348 487 A1. In this case, a substantially cylindrical wobble piston in a cylinder carries out a tumbling movement, which consists of an oscillating stroke movement and a superimposed rotary motion. The rotational movement of the wobble piston in this case serves to open or close an inlet or an opposite outlet in the cylinder, while the oscillating stroke movement fills the coating agent into the cylinder or ejects it out of the cylinder. The wobble piston is in this case driven by a rotating drive shaft via a transfer gear, wherein the transfer gear converts the pure rotational movement of the drive shaft in the tumbling motion.

A disadvantage of this known wobble piston pump is the fact that the flow rate of the wobble piston pump pulsates strongly, which is undesirable when metering coating agents (for example lacquer) in a coating installation. Rather, when used in a coating system for metering paint, it is desirable for the delivery flow to be as constant as possible in accordance with the desired value.

The invention is therefore based on the object to provide a correspondingly improved wobble piston pump. This object is achieved by an inventive wobble piston pump according to the main claim.

The invention comprises the general technical teaching of providing a plurality of pump units in a wobble piston pump, each of which has a cylinder and a wobble piston which, during operation, performs a tumbling movement in the cylinder.

The individual pump units each require - as the conventional wobble piston pump described above - a pulsating Forderstrom the coating agent. In a preferred exemplary embodiment of the wobble piston pump according to the invention, however, the individual pump units are connected on the outlet side to a common pump outlet, so that the blower currents of the individual pump units are superimposed, which leads to a smoothing of the pulsation. In addition, the pump units of the wobble piston pump according to the invention are preferably also connected on the inlet side to a common pump inlet, so that the pump units are filled with the coating agent via the common pump inlet.

On the one hand, the largest possible number of parallel pump units is desirable in this case in order to minimize the pulsations of the Forderstrom as far as possible. On the other hand, complexity and weight of the wobble piston pump increase with the number of pump units connected in parallel. In the preferred exemplary embodiment of the invention, the wobble piston pump therefore has three pump units connected in parallel, which represents a good compromise between the requirement for the lowest possible pulsation of the Forderstrom on the one hand and the demand for the lowest possible weight. However, the invention is not limited to wobble piston pumps with three pump units connected in parallel. Rather, within the scope of the invention, it is also possible to connect a larger or a smaller number of pump units in the wobble piston pump in parallel. For example, the wobble piston pump 2, 4, 5 according to the invention or even 6 pump units connected in parallel. The optimum number of pump units depends on the requirements for the uniformity of the flow rate and on the weight of the wobble piston pump.

In another embodiment of the invention, the tumbling piston pump for the separate promotion of several components (eg parent lacquer and hardener) of the coating composition is suitable. This means that the various components of the coating agent in the wobble pump have no contact with each other to prevent a chemical reaction between the various components. For each component of the coating agent, therefore, preferably at least one pump unit is provided in each case. In each case, a plurality of pump units, which are interconnected on the outlet side and / or inlet side and which jointly convey the respective component, may also be provided for each component of the coating agent. By means of this parallel connection of a plurality of pump units for a specific component, in turn, a smoothing of the delivery flow of the respective component is achieved. For example, the wobble piston pump according to the invention can have a total of six pump units, with three pump units jointly conveying a first component (eg stock paint), while the other three pump units jointly promote a second component (eg hardener). The drive of the wobble piston pump according to the invention is preferably carried out by a common drive shaft which can be driven for example by an electric motor and thus rotates during operation. Between the rotating drive shaft and the individual pump units, a transfer gear is then arranged in each case, which converts the pure rotary motion of the common drive shaft into the combined tumbling movement (rotational and lifting movement) of the wobble pistons. Basically, however, there is also the possibility that the

Drive of the wobble piston pump according to the invention is effected by a linearly oscillating drive element. Again, a transfer gear must be arranged between the drive element and the individual pump units, which then converts the linear oscillating movement of the common drive element in the combined wobble movement.

When driving the wobble piston pump according to the invention by a common drive shaft, the power transmission from the common drive shaft to the various pump units is preferably carried out by a gear transmission.

In a variant of the invention, this gear transmission has a ring gear with an internal toothing and a plurality of planetary gears engaging in the ring gear, each with an external toothing. The common drive shaft in this case drives the ring gear, so that the individual planetary edges rotate with a corresponding ratio, with the individual planetary gears driving one of the pump units in turn.

In contrast, in another variant of the invention, the gear transmission has a central sun gear with external teeth and a plurality of planetary gears engaging in the sun gear each having an external toothing, wherein the common drive shaft drives the central sun gear, so that the planet gears rotate with a corresponding translation. Again, the individual planetary gears of the gear drive then again drive each one of the pump units.

However, the invention is not limited to the above-described variants with regard to the structural design of the gear transmission. Rather, the power distribution from the common drive shaft to the various pump units can also be realized by other types of transmissions. It has already been mentioned in the introduction that the parallel connection of several pump units in the wobble piston pump according to the invention makes it possible to reduce the pulsation of the delivery flow. For this purpose, the individual pump units are preferably driven with a certain phase difference, so that the time course of the flow rates of the individual pump units is correspondingly out of phase. Preferably, the phase difference is equal to 360 ° divided by the number of pump units. For a total of three pump units, the phase difference between the individual pump units is therefore preferably 120 °.

Furthermore, it should be mentioned that the individual wobble pistons preferably consist of a composite of different materials (eg ceramic and steel), which on the one hand enables economic production and on the other hand allows a long service life and, moreover, is associated with a low weight. Preferably, in this case, the piston head (conveying head) of the wobble piston made of ceramic, while the piston skirt (piston skirt) consists of steel. The two materials Rialia of the composite are preferably glued together, pressed or screwed. In technical experiments, it has been found that silicon nitride, zirconium oxide and aluminum oxide are particularly suitable as ceramic materials for the potting flask.

It should generally be mentioned that the individual pump units are preferably made of low-wear materials. For example, the pump units may have material pairings in which both materials are hard. Alternatively, material pairings are possible in which a relatively hard material is paired with a relatively soft material. Furthermore, it is within the scope of the invention, the possibility that the individual pump units are mechanically connected by a separable coupling with a continuous drive shaft. The individual pump units can thus be selectively engaged or disengaged. The pump unit, which is to carry out a conveying operation in each case, is connected to the common drive shaft and driven, while the other pump units are disengaged and therefore not driven. In addition, there is the possibility that the common drive shaft is divided by a plurality of separable couplings into a plurality of drive shaft sections, wherein the individual drive shaft sections each drive at least one of the pump units. Again, the pump units can be selectively engaged or disengaged. At a

Separation of one of the arranged in the drive shaft clutches, however, all pump units are disengaged and thus turned off, the kinematically behind the separated Clutch lie while the kinematically before the separate clutch (motor side) lying pump units work.

It has already been mentioned above that the drive of the wobble piston pump according to the invention is preferably carried out by a rotating drive shaft, wherein the pure rotational movement of the drive shaft is converted by a transmission into the combined tumbling movement of the wobble pistons. This means that the individual wobble pistons perform an oscillating stroke movement and a superimposed rotational movement. The transfer gear in this case controls the piston position of the wobble piston in accordance with a predetermined control curve in dependence on the rotation angle of the drive shaft. For example, the control cam of the transfer gear may be sinusoidal, resulting in a corresponding sinusoidal lifting movement of the wobble piston.

However, there is also the alternative possibility that the control cam has a course that deviates from a sine curve, so that the lifting movement of the wobble piston is not sinusoidal.

In one variant of the invention, the control cam of the reduction gear is lift-free in a region around the dead centers of the piston movement, so that the wobble pistons execute only one rotational movement in the hub-free region in order to close or close the inlet or the outlet to open. The stroke-free region of the piston movement may comprise, for example, a rotational angle range of the planetary gears of at least 5 °, 10 °, 15 °, 20 °, 25 ° or even 30 °. There is even the possibility that the stroke-free rotation angle range up to 60 °. It should also be mentioned that the control cam of the transfer gear defines a delivery phase and a filling phase, wherein the wobble piston pump receives the coating agent in the filling phase and ejects the absorbed coating agent again in the delivery phase. In this case, there is the possibility that the control cam of the transfer gear is shaped so that the delivery phases of the individual pump units connect with each other in time and without any time overlap in order to achieve a pulsation as low as possible flow. In the context of the invention, there is even the possibility that the wobble piston pump outputs a pulsation-free flow. The pulsation of the delivery flow is thus preferably less than 5%, 3% or even less than 2%. Furthermore, it is within the scope of the invention, the possibility that the control cam of the transfer gear is formed so that the lifting movement of the wobble piston in the filling phase is faster than in the delivery phase. Alternatively, there is also the possibility that the control cam of the transfer gear is shaped so that the lifting movement of the wobble piston in the filling phase is slower than in the delivery phase. In a preferred embodiment of the invention, however, the control cam of the transfer gear is designed so that the lifting movement of the wobble piston in the filling phase and / or in the delivery phase with a substantially constant piston speed, which advantageously leads to a correspondingly constant flow rate or filling flow ,

Furthermore, it is possible within the scope of the invention for the control cams of the individual pump units to differ from one another. lent, resulting in correspondingly different piston movements. This may be advantageous, for example, if the wobble piston pump according to the invention promotes various components (eg master lacquer and hardener) of a coating agent which must have a specific mixing ratio. In addition, a different design of the control curves of the individual pump units in a multi-component pump allows the setting of a specific dynamic mixing process in which, for example, first the first component and then the second component is metered more, which can be realized by a corresponding adjustment of the cams.

The mixing ratio of a component A to a component B or a component C can also be adjusted by different piston strokes or different piston diameters.

In the preferred embodiment of the invention, the wobble piston pump has a common coating agent supply line for supplying the coating agent for all pump units. In this coating agent supply line, an inlet-side distributor point is preferably arranged inside the wobble piston pump, from which branch off a plurality of inlet-side branch lines which connect the inlet-side distributor point to the inlet of the individual pump units.

The inlet-side branch lines between the inlet-side distributor point and the pump units preferably have the same length. This is advantageous because the coating agent flowing in via the common coating agent supply line then also reaches the various pump units at the same time. In addition, the inlet-side branch lines between the inlet-side distributor point and the pump units preferably have a kink-free course in order to minimize the flow resistance. Such a kink-free and continuously curved course of the branch lines can be achieved, for example, by a laser sintering technique or by the so-called rapid prototyping, as described, for example, in DE 10 2008 047 118, so that the content of this document in the present description with respect to the Rapid Prototyping is fully attributable.

Preferably, the wobble piston pump has a pump housing, which can be produced by means of rapid prototyping.

The pump housing can then be reworked on the outside and / or inside. For external reworking, for example, offer machining processes. The internal post-processing, on the other hand, can take place, for example, by means of pressure flow laps.

It should also be mentioned that the inlet-side branch lines between the inlet-side distributor point and the pump units preferably have a line path with a minimum flow resistance.

In addition, the inlet-side branch lines preferably connect the inlet-side distributor point to the pump units by the shortest route.

Finally, it should be mentioned that the coating agent supply line and the inlet-side branch lines are preferably dead-space-free, in order to avoid deposits of the coating agent in the lines, color losses in the pump as low as possible and to minimize the rinsing time.

In addition, the wobble piston pump according to the invention preferably has a common coating agent outlet line, which receives and discharges the coating agent conveyed by the individual pump units. In the common coating agent output line, an outlet-side distributor point is preferably arranged within the wobble piston pump, from which a plurality of outlet-side branch lines branch off to the outputs of the individual pump units.

Also, these exhaust-side branch pipes preferably have the above-mentioned characteristics of the intake-side branch pipes (for example, kink-free, dead-space-free, etc.).

It should also be mentioned that the inlet-side distributor point is preferably connected to an inlet-side pressure sensor, which measures the pump admission pressure, wherein the inlet-side pressure sensor can be structurally integrated into the wobble piston pump according to the invention. In addition, the outlet-side distributor point is preferably also connected to an outlet-side pressure sensor, which measures the pump outlet pressure, wherein preferably also the outlet-side pressure sensor is structurally integrated into the wobble piston pump according to the invention.

Furthermore, the wobble piston pump according to the invention preferably also allows flushing, which may be necessary, for example, during a color change. Therefore, the wobble piston pump according to the invention preferably has a flushing medium inlet for supplying a flushing agent and a flushing agent outlet for returning a flushing agent and a Flushing line leading from the flushing agent inlet through the pump units to the flushing agent outlet.

In a variant of the flushing according to the invention, the individual pump units are arranged one behind the other along the flushing agent line. The advantage of such a series passage of the rinsing agent through the individual pump units with respect to a parallel channel guide is the prevention of clogging of the rinsing agent line. In the case of a parallel flushing agent guide through the individual pump units, the flushing agent would always choose the path of the lowest flow resistance, so that individual flow paths could slowly clog up. In another variant of the invention, however, the rinsing agent line branches into a plurality of parallel line branches, which rinse the individual pump units. However, such a parallel routing of the detergent line is - as mentioned above - less preferred.

Preferably, the flushing of the individual pump units is used to flush the piston skirt, which advantageously degrades color leakage along the piston and thus drying of paint behind the piston is prevented, which leads to an improvement in the service life of the wobble piston pump.

The individual pump units preferably each have at least one piston rod seal, which seals the respective wobble piston, wherein the above-mentioned scavenging medium line is preferably guided through the individual piston rod seals. For example, the piston rod seal may have a radially extending flushing bore, through which the flushing agent is passed. The individual piston rod seals preferably have at least two sealing lips which project axially from the piston rod seal and bear against the outer surface of the wobble piston from the outside.

Furthermore, it is within the scope of the invention, the possibility that the conveying direction of the wobble piston pump is reversible to allow a reflow operation (reflow) of the coating system, wherein the coating medium in the course of the reflux operation in the reverse direction flows through the piston tumble pump. For this purpose, however, alternatively, a bypass valve may be provided which bypasses the wobble piston pump. Preferably, this bypass valve is arranged without dead space between the pump inlet and the pump outlet, without the need for additional rinse connections.

In the preferred embodiment of the invention, the wobble piston pump has a line component, in which all fluid lines are arranged, such as the

Branch lines, the detergent line, the bypass line, the coating agent supply line and the coating agent outlet line. The line component therefore has a relatively complex shape and is preferably produced by the rapid prototyping already mentioned in the introduction. Alternatively, however, a casting or machining production of the line component is possible. Preferably, this complex line component is interchangeable, so that the wobble piston pump according to the invention can be repaired in a simple manner by an exchange of the line component.

Finally, it should be mentioned that the invention is not limited to a wobble piston pump as a single component. Rather, the invention also encompasses a coating Anläge or a coating device with such a wobble piston pump for metering a coating means. The coating system according to the invention therefore preferably has an atomizer (eg rotary atomizer, airless device, airmix device, ultrasonic atomizer, etc.) which applies a coating agent (eg wet paint, powder coating) to a component (eg motor vehicle body component). In addition, the coating system according to the invention has the above-described wobble piston pump according to the invention, which is connected on the output side to the atomizer and metered the coating agent as required.

There is the possibility that the wobble piston pump on the inlet side no separate color pressure regulator is connected upstream, since the flow rate is independent of the pump inlet pressure. The waiver of an input-side color pressure regulator advantageously allows a simplification of the structure and thus a cost reduction. The wobble piston pump according to the invention can be arranged in the coating installation according to the invention, for example in a multi-axis coating robot, for example in a robotic arm of the coating robot. However, there is also the alternative possibility that the tumbling piston pump is arranged at a paint removal point or in a color mixing chamber of the coating installation.

Finally, the invention also encompasses the novel use of the aforesaid wobble piston pump according to the invention for conveying a coating composition, in particular lacquer or preservative, such as wax, PVC (polyvinyl chloride) or adhesives in a coating installation. However, the wobble piston pump according to the invention is in principle also suitable for metering other fluids, so that the In the context of the invention, the term used for a coating agent is to be understood in general terms.

Other advantageous developments of the invention are characterized in the subclaims or are explained in more detail below together with the description of the preferred embodiments of the invention with reference to FIGS. Show it:

1 shows a schematic representation of a wobble piston pump according to the invention,

2 shows a perspective view of the wobble piston pump according to FIG. 1, FIG. 3 shows a partially cutaway perspective view of the wobble piston pump according to FIGS. 1 and 2,

Figure 4 is a simplified perspective view of a

Gear transmission in the wobble piston pump according to the figures 1 to 3,

FIG. 5 is another perspective view of the gear transmission of FIG. 4;

FIG. 6 shows a perspective view of a wobble piston of the wobble piston pump according to FIGS. 1 to 5, FIG. 7 shows a cutaway perspective view of the wobble piston pump

Wobble piston according to FIG. 6,

FIG. 8 shows a schematic representation to clarify the coating agent supply to the individual pump units of the wobble piston pump according to the invention,

FIG. 9 shows a schematic perspective view for clarifying the outlet-side cable routing,

FIG. 10 shows a schematic perspective view for clarifying the flushing of the individual pump units of the wobble piston pump according to the invention,

FIG. 11A shows a perspective view of a piston rod seal of the wobble piston pump according to the invention,

11B shows different phases of the movement of a wobble piston in a pump unit of the wobble piston pump according to the invention, FIG.

13 shows the time profile of the flow rate of a wobble piston pump according to the invention with two pump units,

FIG. 14 shows the time profile of the delivery flow in the case of a wobble piston pump according to the invention with three pump units,

Figure 15 is a control cam of a transfer gear for

Conversion of a rotational movement of the drive shaft into a tumbling motion of the wobble piston, FIG. 16 shows a modification of the control cam according to FIG. 15, FIG. 17 shows a further modification of the control cam according to FIG

FIG. 15

FIG. 18 shows a schematic representation of a multicomponent pump according to the invention for the separate delivery of a plurality of components of a coating agent,

19 shows a pump arrangement with a plurality of pumps, which are connected to one another by couplings,

FIG. 20 shows a pump arrangement with a plurality of pumps, which are each connected by a coupling to a common drive shaft,

FIGS. 21A-21D show the time profile of the delivery flow in the case of a pulsation-free wobble piston pump,

FIG. 22 shows a schematic representation of a wobble piston pump according to the invention with three pump units and a dead-space-free bypass valve,

FIG. 23 a schematic representation of a wobble piston pump according to the invention with three pump units during piston flushing,

Figure 24 is a schematic representation of the inlet side of the wobble piston pump according to Figure 1, as well Figure 25 is a schematic representation of the outlet side of the wobble piston pump according to Figure 1. The figures show a wobble piston pump 1 according to the invention, which can be used in a paint shop to meter the paint to be applied as needed.

The wobble piston pump 1 therefore has a paint outlet 2, which is connected to an atomizer 3, wherein the atomizer 3 and the wiring between the paint outlet 2 and the atomizer 3 are shown here only schematically.

In addition, the wobble piston pump 1 has a paint inlet 4, to which a coating agent supply line 5 is connected in order to supply the paint to be metered.

The wobble piston pump 1 has a total of three pump units 6, 7, 8, which each have a cylinder and a guided in the cylinder wobble piston, the structure and operation of the individual pump units 6-8 is largely conventional and later still with reference to the figures 12A -12D is described in detail. The pump units 6-8 are connected in parallel on the inlet side and outlet side, so that the pulsating delivery flows of the individual pump units 6-8 overlap, which leads to a smoothing of the output at the paint outlet 2 flow.

For this purpose, the inlets of the pump units 6-8 are connected via inlet-side branch lines 9-11 to a common inlet-side distributor point 12, which in turn is connected to the paint inlet 4. In the same way, the outlet of the pump units 6-8 is connected via three outlet-side branch lines 13-15 to an outlet-side distributor point 16, which in turn is connected to the paint outlet 2.

In addition, the wobble piston pump 1 has a bypass valve 17, which connects the paint input 4, bypassing the pump units 6-8 directly to the paint outlet 2. The bypass valve 17 is directly between the color input 4 and the

Color output 2 arranged without dead space, which prevents further color losses.

Furthermore, the wobble piston pump 1 according to the invention has an input-side pressure sensor 18.1, which measures the pump inlet pressure at the paint inlet 4. In the same way, an output-side pressure sensor 18.2 is provided, which is connected to the paint outlet 2 and measures the outlet pressure of the wobble piston pump 1.

Finally, the wobble piston pump 1 according to the invention still allows flushing with a flushing agent, which serves to clean the pistons and thereby increases the service life. For this purpose, the wobble piston pump 1 has a Spülmitteleinlass 19 and a Spülmittelauslass 20, wherein a Spülmittelleitung 21 via a flushing valve 22 in series through the pump units 6-8 runs to flush the pump units 6-8, as will be described in detail with reference to Figure 10 ,

Figures 2 and 3 show perspective views of the wobble piston pump 1. It can also be seen that the wobble piston pump 1 driven by a common drive shaft 23 is, with the drive shaft 23 is usually connected to a E- lektromotor.

Figures 4 and 5 show a gear transmission 24, the piston pump 1 in the tumble serves to distribute the torque of the drive shaft 23 to the individual pump units 6-8. For this purpose, the gear transmission 24 has a ring gear 25 and three planet gears 26, 27, 28, wherein the planet gears 26-28 engage with their external teeth in a correspondingly adapted internal toothing of the ring gear 25. The drive shaft 23 is in this case mounted in a bearing 29 and drives the ring gear 25, so that the individual planet gears 26-28 rotate with a corresponding translation. Figure 4 additionally shows a transfer gear 30, which converts the pure rotational movement of the planet gear 26 in a tumbling motion of a wobble piston 31, so that the wobble piston 31 performs a combined rotational and lifting movement in a cylinder 32.

For this purpose, the transfer gear 30 has a control sleeve 33, in which a circumferential control cam is arranged in the form of a groove. In this groove engage control balls 34 which are fixed relative to the planet gear 26 in the circumferential direction, whereby the rotational movement of the planet gear 26 is converted into a combined rotational and lifting movement of the wobble piston 31.

Figures 6 and 7 show the structure of the individual wobble piston 31 from a piston head 35 made of ceramic (eg silicon nitride) and a piston skirt 36 made of hardened steel, wherein the piston head 35 is bonded to the piston skirt 36. In the piston skirt 36 here is a receiving bore 37 for receiving control balls.

Furthermore, it can be seen from FIG. 6 that the piston head 35 has a control groove 38 on its front side in order to release the inlet or outlet of the cylinder 32, as will be described in detail with reference to FIGS. 12A-12D. FIG. 8 shows, in a schematic form, the conduit guides in the wobble piston pump 1 on the inlet side of the pump units 6-8. It can be seen that the branch lines connect 9-11 the inlet-side distribution point 12 by the shortest path and kink-free with the pump units 6-8. Moreover, it can be seen from this illustration that the various branch lines 9-11 between the inlet-side distributor point 12 and the pump units 6-8 have the same channel length, which is important for pulsation-free delivery.

FIG. 9 correspondingly shows the routing in the wobble piston pump according to the invention on the outlet side of the pump units 6-8. It can be seen that the outlet-side branch lines 13-15 between the output-side distribution point 16 and the pump units 6-8 run kink-free and have the same length.

FIG. 10 shows schematically the course of the detergent line 21 in the wobble piston pump 1 according to the invention. It can be seen that the detergent flows between the detergent inlet 19 and the detergent outlet 20 successively through the piston rod seals 39-41, the individual piston rod seals 39-41 respectively in FIG flowed through radial direction. For this purpose, the individual piston rod seals 39-41 each have a radially continuous flushing bore 43, as can be seen from FIGS. IIA and IIA. In addition, it can be seen from these drawings that the piston rod seals 39-41 each have two sealing lips 44, 45, each axially projecting in opposite directions and create from the outside to the lateral surface of the wobble piston 31.

The fundamental mode of operation of the individual pump units 6-8 of the wobble piston pump 1 will now be described below with reference to FIGS. 12A-12D. Thus, the individual pump units 6-8 each have the cylinder 32, in which the wobble piston 31 can perform a wobbling motion, wherein the wobbling movement consists of a combined rotational and lifting movement. At its front end, the wobble piston 31 has the control groove 38 to selectively open an inlet 46 or an outlet 47.

In the following, the filling phase will now be described first with reference to FIG. 12A. This is the wobble piston

31 is rotated so that the control groove 38, the inlet 46 releases, whereas the wobble piston 31 closes the outlet 47 with its lateral surface. The wobble piston 31 is then pulled out axially of the cylinder 32 in the direction of the arrow, whereby the coating agent via the inlet 46 into the cylinder

32 is filled. In this idealized form takes place in the filling phase only a linear lifting movement without an additional rotation of the wobble piston 31st In contrast, FIG. 12B shows the state of the wobble piston 31 at the bottom dead center of the lifting movement. In this state, the wobble piston 31 is rotated about its longitudinal axis so that the inlet 46 is closed, while the inlet 47 is open at the end of the rotational movement, as shown in Figure 12C.

In the delivery phase according to FIG. 12C, the wobble piston 31 is then pushed into the cylinder 32 without a rotational movement, as a result of which the previously accommodated coating agent is forced out of the cylinder 32 via the outlet 47.

Finally, FIG. 12D shows the state at top dead center of the wobble piston 31. In this state, the wobble piston 31 is again rotated in such a way that the inlet 46 is opened, whereas the outlet 47 is closed.

The above-described phases according to FIGS. 12A-12D are then cyclically repeated during operation. FIG. 13 shows the profile of a delivery flow Q as a function of the angle α of the common drive shaft 23 for a wobble piston pump with two pump units connected in parallel. It can be seen that the delivery phases 48 of the individual pump units overlap, resulting in a smoothing of the pulsation.

FIG. 14 shows the same profile of the delivery flow Q for the wobble piston pump 1 according to the invention with the three pump units 6-8. Here, too, superimpose the delivery phases 48 of the individual pump units 6-8, resulting in a correspondingly better smoothing of the flow Q.

Figure 15 shows a possible course of a control cam 49 of the transfer gear 30, the pure rotational movement in the converts desired wobbling motion. It can be seen that the control cam 49 has a region in which the wobble piston 31 in the region of its dead points ausfuhrt no stroke, which corresponds to Figures 12B and 12D.

In addition, it can be seen that the control cam 49 between the dead centers of the wobble piston 31 has an approximately linear region in which the wobble piston 31 thus moves at a constant piston speed, which leads to a constant Forderstrom accordingly.

The goal here is that the sum of all individual demand currents of the pump units is constant in all angular positions. FIG. 16 shows a modification of the control curve according to FIG. 15. A special feature here is that the gradient of the control curve during the filling stroke is relatively steep and relatively flat during the Forderhubs. As a result, the wobble piston 31 moves relatively slowly during the filling stroke relatively quickly and during the Forderhubs relatively slowly.

FIG. 17 shows a modification of the control cam from FIG. 16. In this case, the control curve has a relatively flat gradient during the filling stroke and a relatively large gradient during the Forderhubs. As a result, the wobble piston 31 moves relatively quickly during the Befüllungshubs relatively fast and during the Forderhubs. FIG. 18 shows a multicomponent pump according to the invention

50, which can be used for example in a paint shop, to demand different components of a coating agent separately. For this purpose, the multi-component pump 50 a total of six pump units 51-56, which are each designed as wobble piston pumps. The pump units 51, 55 and 56 serve for metering a first component (eg stock paint) of the coating agent, so that the pump units 51, 55 and 56 are connected in parallel both on the input side and on the output side. This parallel connection in turn has the already mentioned above advantage of smoothing the pulsating flow rates.

The mixing ratio of a component A to a component B can be adjusted by different stroke lengths and different piston diameter.

The other pump units 52, 53, 54, on the other hand, serve for dosing a second component (for example hardener) of the coating agent. These pump units 52-54 are therefore interconnected both on the input side and on the output side and therefore operate in parallel, which advantageously leads to a corresponding smoothing of the pulsation.

Another special feature of the multicomponent pump 50 is the drive through a central sun gear 57.

FIG. 19 shows a pump arrangement with an electric motor 58 and a plurality of pump units 59-62, which are each connected to one another or to the electric motor 58 by separable couplings 63-66. The pump assembly thus has a drive shaft 67 which is divided into a plurality of shaft sections, wherein the individual shaft sections each drive one of the pump units 59-62. FIG. 20 shows a somewhat modified pump arrangement, which partially corresponds to the pump arrangement according to FIG. 19, so that reference is made to the above description to avoid repetition, the same reference numerals being used for corresponding details.

A special feature of this exemplary embodiment is that the drive shaft 67 passes through and the individual pump units 59-62 can each be selectively connected to the drive shaft 67 by the associated coupling 63-66.

FIGS. 21A-21D show the time profile of the delivery flow in a pulse-action-free wobble piston pump with three pump units. FIGS. 21A-21C show the delivery flows Q1-Q3 of the individual pump units, while FIG. 21D shows the total delivery rate Q _{GES of} the wobble piston pump resulting from the superposition of the delivery flows Q1-Q3 of the individual pump units. The flow rates Q1-Q3 of the individual pump units are selected by a suitable design of the respective control curve so that the entire flow rate Q _{GES is} pulsation-free.

Figure 22 shows a schematic representation of a wobble piston pump according to the invention with three pump units 6-8 and a bypass valve 17 between the color input and the color output. The wobble piston pump according to FIG. 22 largely corresponds to the wobble piston pump according to FIG. 1, so that reference is made to the above description to avoid repetition, the same reference numerals being used for corresponding details.

It should be noted that the bypass valve 17 is arranged without dead space between the color input and the color output, without additional connection holes are required. FIG. 23 shows a schematic and simplified illustration of a wobble piston pump according to the invention with three pump units 6-8, this wobble piston pump likewise largely matching the wobble piston pump according to FIG. 1, so that reference is made to the above description to avoid repetition, with corresponding details the same reference numerals are used. In this illustration it is shown how the pistons of the individual pump units 6-8 are flushed via the flushing valve 22 with a flushing agent, wherein the individual pump units 6-8 are flushed serially. The pump units 6-8 are thus arranged one behind the other along the detergent line 21.

Finally, FIGS. 24 and 25 show that the inlet-side branch lines 9-11 have the same length as the outlet-side branch lines 13-14 have the same length. This is advantageous because the coating agent flowing in via the common coating medium feed line 5 then also reaches the various pump units 6-8 simultaneously. The invention is not limited to the preferred embodiments described above. Rather, a variety of variants and modifications is possible, which also make use of the inventive idea and therefore fall within the scope. In this context, it should be mentioned that the appended subclaims contain independently objects worthy of protection and therefore belong to the subject matter of this application, irrespective of the claims referred to. For example, the invention also claims independent of the other features of the invention Protection for the above-described piston rod seal, the flush, the conduit member and the novel wobble piston.

List of reference numbers:

1 wobble piston pump

2 color output

3 atomizers

4 color input

5 coating agent supply line

6-8 pump units

9-11 inlet branch lines

12 inlet side distribution point

13-15 Outlet-end branch lines

16 Outlet-side distribution point

17 bypass valve

18.1 Input side pressure transducer

18.2 Output side pressure sensor

19 detergent inlet

20 rinse aid outlet

21 detergent line

22 detergent valve

23 drive shaft

24 gear transmission

25 ring gear

26-28 planet gears

29 bearings

30 transfer gear

31 wobble piston

32 cylinders

33 control sleeve

34 control balls

35 piston head

36 piston shaft

37 receiving bore

38 tax credit

39-41 piston rod seal line part

flushing

sealing lip

inlet

outlet

delivery phases

cam

Multi-component pump-56 pump units

sun

electric motor

-62 pump unit

-66 couplings

drive shaft

Claims

1. wobble piston pump (1) for metering a coating agent in a coating installation, characterized by a plurality of pump units (6-8) each having a cylinder (32) and each having a wobble piston (31) which, during operation, wobbles in the cylinder (32 ).

2. wobble piston pump (1) according to claim 1,

characterized,

a) that the wobble piston (31) of the pump units (6-8) via a gear transmission (24) are driven by a common drive shaft, and / or

b) that the gear transmission (24) has a ring gear (25) with an internal toothing and a plurality of planetary gears (26-28) engaging in the ring gear (25), each with an external toothing, wherein the ring gear (25) is driven by a common drive shaft, while the wobble piston (31) of the individual pump units (6-8) via the planetary gears (26-28) of the gear transmission (24) are driven, or

c) that the gear transmission has a central sun gear (57) with an external toothing and a plurality of in the sun gear (57) engaging planetary gears each having an external toothing, wherein the common drive shaft drives the sun gear (57), while the wobble piston (31) of the individual pump units (6-8) are driven by the planet gears of the gear transmission.

3. wobble piston pump (1) according to one of the preceding claims, characterized

a) that the individual pump units (6-8) each promote a pulsating flow of the coating agent, and

b) that the pump units (6-8) are connected on the outlet side to a common pump outlet (2), so that the pulsating flow rates of the individual pump units (6-8) overlap, which leads to a smoothing of the pulsation, and / or

c) that the pump units (6-8) are connected on the inlet side to a common pump inlet (4), so that the pump units (6-8) receive the coating agent via the common pump inlet (4).

4. wobble piston pump (1) according to one of claims 1 to 2, characterized

a) that the wobble piston pump (1) is suitable for the separate delivery of several components of the coating composition, and

b) that for each component of the coating agent in each case at least one pump unit (51-56) is provided, or

c) that for each component of the coating agent each have a plurality of pump units (51-56) are provided, which are interconnected on the inlet side and the outlet side and promote the respective component together.

5. wobble piston pump (1) according to one of the preceding claims, characterized

a) that the pump units (6-8) with a certain

Phase difference driven by a common drive shaft, and / or b) that the phase difference is equal to 360 ° divided by the number of pump units (6-8).

6. wobble piston pump (1) according to one of the preceding claims, characterized

a) that the individual wobble pistons (31) each consist of a composite of different materials,

and or

b) that the individual wobble pistons (31) each consist of ceramic and / or steel and / or hard metal, and / or

c) that the individual wobble pistons (31) each have a piston bottom (35) made of ceramic and / or hard metal and a piston skirt (36) made of steel and / or hard metal, and / or

d) that the piston head (35) with the piston skirt (36) glued, pressed or screwed, and / or

e) that the ceramic contains silicon nitride, zirconium oxide or aluminum oxide.

7. wobble piston pump (1) according to one of the preceding claims, characterized

a) that the individual pump units (6-8) is mechanically connected by a separable coupling (63-66) with a continuous drive shaft, or

b) that a common drive shaft by separable

Couplings is divided into several sections, wherein the individual portions of the drive shaft each drive at least one of the pump units (6-8).

8. wobble piston pump (1) according to one of the preceding claims, characterized a) that the individual pump units (6-8) by a respective transfer gear (30) with a common drive shaft (23; 67) are connected, and

b) that the transfer gear (30) converts a rotational movement of the drive shaft (23; 67) into a combined rotational and lifting movement of the respective wobble piston (31), or

c) that the transfer gear (30) converts an oscillating lifting movement of the drive shaft (23; 67) into a combined rotational and lifting movement of the wobble pistons (31).

9. wobble piston pump (1) according to claim 8,

characterized ,

a) that the transfer gear (30) the piston position of the

Wobble piston (31) according to a predetermined

Control cam (49) in response to the rotation angle of the drive shaft controls, and / or

b) that the control cam (49) of the transfer gear from a

Sine curve deviates so that the lifting movement of the tundish piston (31) is not sinusoidal.

10. wobble piston pump (1) according to claim 9,

characterized,

a) that the control cam (49) of the transfer gear in a

Area is free of lift around the dead centers of the piston movement, so that the wobble piston (31) perform only a rotational movement in the stroke-free area, and / or b) that the stroke-free area of the piston movement a

Rotation angle range of the planet gears (26-28) of at least 5 °, 10 °, 15 °, 20 °, 25 °, 30 °, 40 °, 50 ° or 60 °.

11. wobble piston pump (1) according to claim 9 or 10,

characterized, a) that the control cam (49) has a delivery phase and a filling phase, wherein the wobble piston pump (1) receives the coating agent in the filling phase and ejects the absorbed coating agent again in the delivery phase, and

b) that the delivery phases of the individual pump units (6-8) adjoin one another without gaps in time and without time overlap in order to achieve a delivery flow that is as low in pulsation as possible.

12. wobble piston pump (1) according to one of claims 9 to 11, characterized

a) that the lifting movement of the wobble piston (31) in the filling phase is faster than in the delivery phase, o-

b) that the lifting movement of the wobble piston (31) in the filling phase is slower than in the delivery phase.

13. wobble piston pump (1) according to one of claims 9 to 12, characterized

a) that the lifting movement of the wobble piston (31) takes place in the filling phase with a substantially constant piston speed and / or

b) that the lifting movement of the wobble piston (31) takes place in the delivery phase with a substantially constant piston speed, so that the delivery flow in the delivery phase is substantially constant.

14. wobble piston pump (1) according to one of claims 9 to 13 and claim 4, characterized in that the control cams, the piston strokes and / or the piston diameter of the individual pump units (6-8) are different in order to set a certain mixing ratio of the components ,

15. wobble piston pump (1) according to one of the preceding claims, characterized by

a) a common coating agent supply line (5) for

Supply of the coating agent for all pump units (6-8),

b) an inlet-side distribution point (12), which in the

Coating agent supply line (5) is arranged, and c) a plurality of inlet-side branch lines (9-11), which branch in the inlet-side distribution point (12) of the common coating agent supply line (5) and lead to the individual pump units (6-8).

16. wobble piston pump (1) according to claim 15,

characterized in that

a) that the inlet-side branch lines (9-11) between the inlet-side distribution point (12) and the pump units (6-8) have substantially the same length, and / or

b) that the inlet-side branch lines (9-11) between the inlet-side distributor point (12) and the pump units (6-8) are kink-free, and / or

c) that the inlet-side branch lines (9-11) between the inlet-side distributor point (12) and the pump units (6-8) have a line path with a minimum flow resistance, and / or

d) that the inlet-side branch lines (9-11) connect the inlet-side distributor point (12) to the pump units (6-8) by the shortest route, and / or

e) that the coating agent supply line (5) and the inlet-side branch lines (9-11) are free of dead space.

17. wobble piston pump (1) according to one of the preceding claims, characterized by a) a common coating agent output line for receiving the coating agent from all pump units (6-8),

b) an outlet-side distribution point (16), which in the

And c) a plurality of outlet-side branch lines (13-15) branching from the common coating agent exit line in the outlet-side distribution point (16) and leading to the individual pump units (6-8).

18. wobble piston pump (1) according to claim 17,

characterized in that

a) that the outlet-side branch lines (13-15) between the outlet-side distribution point (16) and the pump units (6-8) have substantially the same length, and / or

b) that the outlet-side branch lines (13-15) between the outlet-side distribution point (16) and the pump units (6-8) are kink-free, and / or

c) that the outlet-side branch lines (13-15) between the outlet-side distributor point (16) and the pump units (6-8) have a conduit with a minimum flow resistance, and / or d) that the outlet-side branch lines (13-15) are the outlet side Connect the distribution point (16) to the pump units (6-8) by the shortest route, and / or e) that the coating agent outlet line and the outlet-side branch lines (13-15) are free of dead space.

19. wobble piston pump (1) according to one of claims 15 to 18, characterized a) that the inlet-side distribution point (12) is connected to an inlet-side pressure sensor (18.1), which measures the pump pressure, and / or

b) that the outlet-side distribution point (16) is connected to an outlet-side pressure sensor (18.2), which measures the pump outlet pressure.

20. wobble piston pump (1) according to one of the preceding claims, characterized by

a) a rinsing agent inlet (19) for supplying a rinsing agent,

b) a Spülmittelauslass (20) for returning the detergent, and

c) a rinsing agent line (21), which from the rinsing agent inlet (19) through the pump units (6-8) to the

Rinsing agent outlet (20) leads.

21. wobble piston pump (1) according to claim 20,

characterized,

a) that the detergent line (21) in the tumbling pump (1) is free of branching, and / or

b) that the individual pump units (6-8) one each

Piston rod seal (39-41) which seal the respective wobble piston (31), wherein the Spülmit- telleitung (21) through the individual piston rod seals (39-41) is guided, and / or

c) that the rinsing agent line (21) in each case radially through a radially extending flushing bore (43) in the piston rod seals (39-41) is passed, and / or

d) that the pump units (6-8) along the rinsing agent line (21) are arranged one behind the other, so that the pump units (6-8) are rinsed serially.

22 wobble piston pump (1) according to one of the preceding claims, characterized

a) that the individual pump units (6-8) each have a piston rod seal (39-41), which seal the respective wobble piston (31), and

b) that the piston rod seals (39-41) each have at least two sealing lips (44, 45) which protrude axially from the piston rod seal (39-41) and create from the outside to the lateral surface of the wobble piston (31), and / or

c) that the piston rod seals (39-41) each have a piston ridge trailing rinse.

23. wobble piston pump (1) according to one of the preceding claims, characterized in that the conveying direction of the

Wobble piston pump (1) is reversible to allow a reflow operation of the coating plant, in which the coating agent is guided back through the wobble piston pump (1).

24. wobble piston pump (1) according to any one of the preceding claims, characterized

a) that an integrated bypass valve (17) is provided for bypassing all the pump units (6-8) between the pump inlet (4) and the pump outlet (2) via a bypass line, and / or

b) that the bypass valve (17) dead space between the

Pump inlet (4) and the pump outlet (2) is arranged.

25. wobble piston pump (1) according to one of the preceding claims, characterized

a) that all fluid lines of the wobble piston pump (1) in a single line component (42) of the wobble piston Benpumpe (1) are arranged, in particular the

Branch lines (9-11, 13-15), the rinsing agent line (21), the bypass line, the coating medium (5) and the coating agent output line, and / or

b) that the conduit component (42) is exchangeable,

and or

c) that at least one component of the wobble piston pump (1) is produced by a rapid prototyping method.

26. wobble piston pump (1) according to one of the preceding claims, characterized in that the wobble piston pump (1) promotes a pulsation-free flow (Q _GES ).

27. Coating plant, in particular painting plant for painting motor vehicle body components, with

a) an atomizer (3) for applying a coating agent,

b) a metering pump (1) for metering the coating agent, wherein the metering pump (1) is connected on the output side to the atomizer (3),

characterized ,

c) that the metering pump (1) is a wobble piston pump (1)

according to one of the preceding claims.

28 coating system according to claim 27, characterized in that the wobble piston pump (1) on the inlet side no color pressure regulator is connected upstream.

29. Coating plant according to one of claims 27 to 28, characterized

a) that the wobble piston pump (1) in a multi-axis

Coating robot is arranged, in particular in a robot arm of the coating robot, or b) that the tumbling piston pump (1) is arranged at a paint removal point of the coating system, or c) that the wobble piston pump (1) is arranged in a paint mixing chamber of the coating system.

30. Use of a tumbling piston pump (1) according to any one of claims 1 to 26 for the promotion of a coating agent, in particular paint or preservatives such as wax or PVC, in a coating system or for the promotion of adhesive.

* * * * *