EP3991861A1 - High-pressure cleaning device - Google Patents

Abstract

The invention relates to a high-pressure cleaning device with a high-pressure pump (16), comprising a suction chamber (50), at least one pump chamber (52) downstream of this, in which liquid is pressurized, and a pressure chamber (56) downstream of the pump chamber (52), wherein the high-pressure cleaning device (10) has an operating unit (24) on which or to which a discharge unit (36, 41) in the form of a low-pressure cleaning agent nozzle (37, 42) is arranged or connected and which is connected via a high-pressure line (22) to the Pressure chamber (56) can be brought into flow connection, and an admixing device (80) via which a cleaning chemical can be admixed to the liquid in the pressure chamber (56). In order to further develop such a high-pressure cleaning device so that it is more user-friendly, the invention proposes that the high-pressure cleaning device (10) have a detection unit (136) with which it can be detected that a liquid pressure on the pressure side of the pump chamber (52) falls below a threshold pressure, a A control unit (76) coupled to the detection unit (136), a notification unit (34) coupled to the control unit (76), on which a notification can be provided to an operator that the high-pressure cleaning device (10) is in a cleaning agent mode, and an input unit (28), via which the operator can specify a mixing ratio of the cleaning chemical with the liquid.

Description

The invention relates to a high-pressure cleaning device with a high-pressure pump, comprising a suction chamber, at least one pump chamber downstream of this, in which liquid is pressurized, and a pressure chamber downstream of the pump chamber, with the high-pressure cleaning device having an operating unit on or to which a discharge unit in Is arranged or connected in the form of a low-pressure cleaning agent nozzle and which can be flow-connected to the pressure chamber via a high-pressure line, and an admixing device via which a cleaning chemical can be admixed to the liquid in the pressure chamber.

In such a high-pressure cleaning device, the liquid that is pressurized in the pump chamber is mixed with the cleaning chemical in the pressure chamber and a mixture of liquid and cleaning chemical is provided. As a result, the cleaning effect of the high-pressure cleaning device can be increased. The mixture is conveyed to the operating unit via the high-pressure line and discharged via the discharge unit in the form of the low-pressure cleaning agent nozzle. Such a discharge unit can be used with the high-pressure cleaning device instead of a discharge unit that can be used as an alternative in the form of a high-pressure nozzle. The high-pressure nozzle has a comparatively small opening cross-section, and liquid emerges under high pressure with a comparatively low volume flow. In contrast, the low-pressure cleaning agent nozzle has a comparatively large opening cross section, and the mixture of liquid and the cleaning chemical emerges with a comparatively high volume flow and low pressure.

The object of the present invention is to further develop a generic high-pressure cleaning device that is more user-friendly.

This object is achieved according to the invention in a high-pressure cleaning device of the type mentioned at the outset in that the high-pressure cleaning device has a detection unit with which it can be detected that a fluid pressure on the pressure side of the pump chamber falls below a threshold pressure, a control unit coupled to the detection unit, an information unit coupled to the control unit, at which an indication can be provided to an operator that the high-pressure cleaning device is in a detergent mode, and an input unit via which the operator can specify a mixing ratio of the cleaning chemicals with the liquid.

The present invention incorporates the idea that when the operating unit is actuated during operation of the high-pressure cleaning device using the low-pressure cleaning agent nozzle on the pressure side of the pump chamber, there is a rather low liquid pressure compared to using a high-pressure nozzle. The fact that the pressure falls below a threshold value can be detected with the detection unit and a relevant signal can be provided to the control unit. The control unit evaluates the signal and can conclude that the low-pressure detergent nozzle is used as the discharge unit. The control unit assumes that it is in a detergent mode. This is signaled to the operator via the notification unit. In this way, the operator is informed in a user-friendly manner that the high-pressure cleaning device is in the detergent mode. Using the input unit coupled to the control unit, the operator can specify the mixing ratio of the cleaning chemical with the liquid in a user-friendly manner and thereby influence the cleaning effect.

“On the pressure side of the pump chamber” is understood here in particular to mean that the fluid pressure can be detected on or in a chamber or a fluid line which is/are arranged downstream of a pressure valve separating the pump chamber from the pressure chamber. This can in particular also be understood to mean a liquid line connected to the pressure chamber or opening into it.

It is favorable if the fluid pressure in the high-pressure pump can be detected with the detection unit.

The fact that the pressure falls below a threshold value on or in the pressure chamber can preferably be detected with the detection unit. For example, the detection unit is arranged for this purpose on the pressure chamber or on a liquid line opening into it.

It is favorable if the mixing ratio can be predetermined in stages. For example, a plurality of mixing ratios is provided, which the operator can increment or decrement step by step using input elements.

Alternatively or additionally, it can be provided that the mixing ratio can be specified continuously.

The notification unit can be configured in a variety of ways. For example, it is an optical or acoustic notification unit.

In a preferred embodiment it is favorable if the indication unit is or comprises a display unit. The display unit can have an optical image display, which symbolizes the user taking the detergent mode. For example, an icon of the low-pressure detergent nozzle is displayed. The specification of the mixing ratio can also be shown on the display unit.

The input unit and the display unit preferably form an integrated input/display unit or are designed as such, for example as a touchscreen.

Information relating to the mixing ratio can preferably be made available on the notification unit. In particular, as already mentioned, this can preferably be displayed on a display unit. If the mixing ratio can be adjusted in stages, For example, the display unit can show which level of mixing ratio is selected by the operator.

It is favorable if the input unit and/or the notification unit are arranged on the operating unit or are encompassed by it. As a result, the operator can be informed in a user-friendly manner on the operating unit about entering the detergent mode and/or specify the mixing ratio on the operating unit in a user-friendly manner.

It has proven to be advantageous if information can be transmitted wirelessly from the input unit to the control unit and/or from the control unit to the notification unit.

In an advantageous implementation of the high-pressure cleaning device according to the invention, it is favorable if a volume flow of the liquid conveyed with the high-pressure pump can be controlled via the input unit. By controlling the volume flow of the liquid, the mixing ratio can be influenced and also controlled. For example, it can be provided that in the cleaning agent mode the liquid in the pressure chamber is admixed with a constant or essentially constant amount of cleaning chemical, even with different volume flows. Due to the different volume flow of the pressurized liquid, this affects the mixing ratio of the liquid with the cleaning chemical.

It is favorable if the high-pressure pump comprises a return line, via which the pressure chamber is in flow connection with the suction chamber, and a valve unit, with which a free cross-sectional area of the return line can be changed, a drive unit assigned to the valve unit and coupled to the control unit, with the volume flow is controllable by depending on the predetermined mixing ratio, the free cross-sectional area of the return line is variable. In practice, this proves to be a reliable and constructively simple way of making the volume flow of the liquid conveyed with the high-pressure pump dependent on the operator's specification to control. Depending on the signal from the input unit, the control unit can activate the drive unit so that the valve unit increases or decreases the free cross-sectional area of the return line. This increases or decreases the volume flow of the liquid from the pressure chamber into the suction chamber. This reduces or increases the amount of liquid delivered by the high-pressure pump. Corresponding to the above statements, the mixing ratio can be increased or decreased when adding a cleaning chemical.

If the mixing ratio is preset in stages, it is provided in particular that the valve unit can be adjusted in stages via the drive unit. This can in particular be understood to mean that a valve body of the valve unit can assume different, discrete relative positions relative to a valve seat of the valve unit, the free cross-sectional area being of different size depending on the relative position.

Alternatively or additionally, it can be provided that the volume flow of the pumped liquid can be controlled by controlling a drive motor of the high-pressure pump. Here, for example, a phase control is used to increase or decrease the volume flow by increasing or decreasing the motor power.

In the case of a high-pressure pump in the form of an axial piston pump, the drive motor can have an adjustable swash plate, by adjusting which the stroke of the axial piston can be changed, as an alternative or in addition to controlling the volume flow. Increasing the angle of inclination of the swash plate can increase the stroke and increase the flow rate, while decreasing the angle of inclination of the swash plate can decrease the stroke and decrease the flow rate.

It is advantageous if the admixing device has a receptacle for a container with the cleaning chemicals, one arranged in the pressure chamber Injector and a supply line from the receptacle to the injector. The injector is designed in such a way that the pressure in the pressure chamber when the cleaning agent mode is adopted is of such an amount that the injector draws in the cleaning chemical from the container via the feed line. The aspirated chemical is mixed with the pressurized liquid in the injector. The mixture can be discharged via the low-pressure cleaning agent nozzle.

The return line and/or the feed line can also be referred to as a return channel or as a feed channel.

The injector is in particular a Venturi injector.

As explained above, the volume flow of the liquid delivered by the high-pressure pump is preferably controlled as a function of the operator's specification on the input unit. The amount of cleaning chemical that can be mixed in via the injector can even be kept constant or essentially constant in the cleaning agent mode, and a change in the volume flow changes the mixing ratio.

The high-pressure cleaning device, in particular the high-pressure pump, preferably has a metering valve as an alternative or in addition to the return line and the valve unit, with which the metering of the cleaning chemical and thus the mixing ratio with the liquid can be influenced. The dosing valve is, for example, coupled to the control unit and/or can be actuated on the input unit depending on the specification of the operator. The dosing valve is preferably connected to the supply line mentioned above.

In an advantageous implementation of the high-pressure cleaning device, it proves to be favorable if the detection unit can detect whether the liquid pressure in the supply line falls below the threshold pressure. When using the low-pressure detergent nozzle, the liquid pressure is at The pressure chamber has a relatively low value when the operating unit is actuated (in particular, the pressure is lower than the ambient pressure of the atmosphere (approximately less than 1 bar)). The injector, in particular the Venturi injector, can suck in the cleaning chemicals via the supply line. In practice, the detection of the pressure in the supply line at the pressure chamber has proven to be reliable in order to ensure that the low-pressure cleaning agent nozzle is provided as the discharge unit.

It is favorable if the detection unit includes a pressure sensor. The pressure sensor can be used to measure the pressure on or in the pressure chamber over such a large pressure range that the pressure can be reliably detected when a low-pressure detergent nozzle is connected on the one hand and a high-pressure nozzle is connected on the other, which will be discussed below.

In another advantageous embodiment, it can be provided that the detection unit includes a pressure switch, for example a membrane switch. If it is only to be detected whether the liquid pressure at or in the pressure chamber falls below or exceeds the threshold pressure, a pressure switch can be used in a structurally simple configuration.

Provision can be made for the high-pressure cleaning device to assume a non-regulation mode in the detergent mode, in which the liquid pressure is not regulated.

It is favorable if the high-pressure cleaning device has a further discharge unit in the form of a high-pressure nozzle, which can be connected to or arranged on the operating unit instead of the low-pressure cleaning agent nozzle, and if the detection unit can detect that the liquid pressure on the pressure side of the pump chamber exceeds a threshold pressure, wherein an indication can be provided on the indication unit that the high-pressure cleaning device is in high-pressure mode. Sets the operator the high-pressure nozzle instead of the low-pressure cleaning agent nozzle, it can be determined via the detection unit when the operating unit is actuated that the liquid pressure on the pressure side of the pump chamber, in particular on or in the pressure chamber, exceeds a threshold pressure, preferably the threshold pressure mentioned at the outset. The control unit interprets this as entering a high pressure mode. The operator is informed in a user-friendly manner on the notification unit that he is in high-pressure mode. For example, a symbol of a high-pressure nozzle is displayed on a notification unit designed as a display unit.

The operator can specify a liquid pressure for the control unit, preferably via the input unit, with the liquid pressure being controllable by the control unit. The operator can influence the liquid pressure in a user-friendly manner via the input unit. Specifications can be evaluated by the control unit and implemented to control the liquid pressure.

In particular, the liquid pressure can be predetermined in stages. For example, a plurality of pressure stages of the high-pressure pump is provided, which the operator can specify via the input unit. The pressure levels can be incremented or decremented using buttons, for example.

Alternatively or in addition, it can be provided that the liquid pressure can be predetermined continuously.

It proves to be advantageous if the liquid pressure can be controlled as a function of the predetermined liquid pressure by changing the free cross-sectional area of the aforementioned return line. Depending on the specified liquid pressure, the control unit can control the drive unit in such a way that the valve unit releases the return line to different extents. This increases or decreases the volume flow from the pressure chamber to the suction chamber. The pump pressure at the outlet of the high-pressure pump can thereby be reduced or increased in the high-pressure mode.

Alternatively or in addition, it is possible to control the liquid pressure by controlling the motor unit (for example a phase angle control) and/or by changing the inclination of the swash plate in an axial piston pump.

It proves to be particularly advantageous if the high-pressure cleaning device adopts a control mode in the high-pressure mode in which the liquid pressure is controlled. To this end, it is particularly advantageous if the detection unit includes a pressure sensor with which the fluid pressure on the pressure side of the pump chamber can be determined even when the high-pressure mode is adopted. Control takes place in particular by changing the free cross-sectional area of the aforementioned return line, in that the control unit controls the drive unit of the valve unit depending on the signal from the pressure sensor and regulates the liquid pressure to the liquid pressure specified by the operator via the input unit.

The fluid pressure that can be detected with the detection unit, specifically the pressure sensor, can be, for example, the pump pressure of the fluid as it is present at a pump outlet of the high-pressure pump. The liquid pressure can also be a pressure coupled to the pump pressure, so that a known relationship between the liquid pressure and the pump pressure can be used to determine the latter by measuring the liquid pressure.

The pump outlet is arranged, for example, on the pressure chamber or is in flow connection with it.

The notification unit is preferably a display unit on which information associated with the predetermined fluid pressure can be displayed to the operator. For example, if the fluid pressure is specified in stages, the pressure level specified by the operator is shown on the display unit. Alternatively or additionally it can be provided that on the display unit an absolute value of the liquid pressure or a pump pressure is displayed at the outlet of the high-pressure pump.

The display unit is preferably the same display unit on which information regarding the mixing ratio of the cleaning chemical with the pressurized liquid is displayed when the detergent mode is entered. The display unit can display different image content depending on whether the detergent mode or the high-pressure mode is present.

It is favorable if the input unit comprises input elements with which the mixing ratio can be specified when the detergent mode is present and with which the liquid pressure can be specified when the high-pressure mode is present. As a result, the same input elements can be used for specifying the liquid pressure in the high-pressure mode on the one hand and for specifying the mixing ratio of liquid and cleaning chemical on the other. Separate input elements are not required. The high-pressure cleaning device thus proves to be more user-friendly.

Figur 1:

eine perspektivische Darstellung eines erfindungsgemäßen Hochdruckreinigungsgerätes, umfassend eine Hochdruckpumpe;

Figur 2:

eine Anzeigeeinheit und eine Eingabeeinheit einer Bedieneinheit des Hochdruckreinigungsgerätes aus Figur 1;

Figur 3:

die Anzeigeeinheit und die Eingabeeinheit, wenn das Hochdruckreinigungsgerät einen Hochdruckmodus einnimmt, sechs unterschiedliche Druckstufen symbolisierend;

Figur 4:

die Anzeigeeinheit und die Eingabeeinheit, wenn das Hochdruckreinigungsgerät einen Reinigungsmittelmodus einnimmt, drei unterschiedliche Dosierungen einer Reinigungschemikalie symbolisierend;

Figur 5:

eine Draufsicht auf die Hochdruckpumpe des Hochdruckreinigungsgerätes aus Figur 1;

Figur 6:

eine Seitenansicht der Hochdruckpumpe;

Figur 7:

eine Schnittansicht (teilweise) längs der Linie 7-7 in Figur 5;

Figur 8:

eine Schnittansicht (teilweise) längs der Linie 8-8 in Figur 6;

Figur 9:

eine Schnittansicht (teilweise) längs der Linie 9-9 in Figur 5, wobei eine Ventileinheit der Hochdruckpumpe eine Schließstellung einnimmt;

Figur 10:

eine Darstellung entsprechend Figur 9, wobei die Ventileinheit eine Offenstellung einnimmt und ferner eine Antriebseinrichtung dargestellt ist, die der Ventileinheit zugeordnet ist;

Figur 11:

eine vergrößerte Darstellung von Detail A in Figur 9 und

Figur 12:

eine vergrößerte Darstellung von Detail B in Figur 10.

The following description of preferred embodiments of the invention, in conjunction with the drawing, serves to explain the invention in more detail. Show it:

Figure 1:

a perspective view of a high-pressure cleaning device according to the invention, comprising a high-pressure pump;

Figure 2:

a display unit and an input unit of a control unit of the high-pressure cleaning device figure 1 ;

Figure 3:

the display unit and the input unit, when the high-pressure cleaning device assumes a high-pressure mode, symbolizing six different pressure levels;

Figure 4:

the display unit and the input unit, when the high-pressure cleaning device assumes a cleaning agent mode, symbolizing three different dosages of a cleaning chemical;

Figure 5:

a plan view of the high-pressure pump of the high-pressure cleaning device figure 1 ;

Figure 6:

a side view of the high-pressure pump;

Figure 7:

a sectional view (partial) along the line 7-7 in figure 5 ;

Figure 8:

a sectional view (partial) along line 8-8 in figure 6 ;

Figure 9:

a sectional view (partial) along the line 9-9 in figure 5 , wherein a valve unit of the high-pressure pump assumes a closed position;

Figure 10:

a representation accordingly figure 9 wherein the valve unit occupies an open position and further a drive device is shown, which is associated with the valve unit;

Figure 11:

an enlarged view of detail A in figure 9 and

Figure 12:

an enlarged view of detail B in figure 10 .

figure 1 shows a perspective view of an advantageous embodiment of a high-pressure cleaning device according to the invention, which is given the reference number 10 . The high-pressure cleaning device 10 includes a motor pump unit 12 , shown only schematically, which includes a drive motor 14 and a high-pressure pump 16 . For example, the high-pressure pump 16 is flanged to the drive motor 14 .

The high-pressure pump 16 has a pump inlet 18 to which a feed line for liquid to be pressurized, in particular water, can be connected. Furthermore, the high-pressure pump 16 has a pump outlet 20 to which a high-pressure line 22, in this case a high-pressure hose, for pressurized liquid can be connected.

A control unit 24 of the high-pressure cleaning device 10, designed as a high-pressure pistol 26, is connected to the high-pressure line 22.

An input unit 28 is arranged on the high-pressure gun 26 and includes input elements for actuation by an operator. In particular, the input elements have a "+" button 30 and a "-" button 32 . The high-pressure gun 26 also has a display unit 34 . The display unit 34 is adjacent to the input unit 28, for example. The input unit 28 and the display unit 34 could also be integrated into one another and designed as a touch screen, for example. The display unit 34 includes an optical image display and forms an information unit of the high-pressure cleaning device 10. Information can be displayed visually on the display unit 34.

The high-pressure cleaning device 10 has a discharge unit 36 in the form of a low-pressure cleaning agent nozzle 37 . The high-pressure cleaning device 10 also includes a discharge unit 38 in the form of a high-pressure nozzle 39. Alternatively or additionally, the high-pressure cleaning device 10 can also have a discharge device 40, which includes a plurality of discharge units. In particular, a discharge unit 41 is provided, configured as a low-pressure detergent nozzle 42, and a discharge unit 43, configured as a high-pressure nozzle 44.

Optionally, the operator can connect the dispensing unit 36, the dispensing unit 38 or the dispensing device 40 to the high-pressure gun 26 and bring it into fluid communication with it. With the discharge device 40, the operator can optionally use the low-pressure cleaning agent nozzle 42 or select the high pressure nozzle 44 and thereby place it in fluid communication with the high pressure line 22 .

Depending on which discharge unit is connected or selected, a different cross-section is provided on the outlet side through which the pressurized liquid emerges. At the high-pressure nozzles 39 and 44, cleaning liquid emerges under high pressure with a small cross-sectional area and a rather low volume flow. In contrast, the low-pressure cleaning agent nozzles 37 and 42 have a significantly larger opening cross section, and liquid emerges with a high volume flow and under rather low pressure.

By selecting a high-pressure nozzle 39 or 44 on the one hand or a low-pressure cleaning agent nozzle 37 or 42 on the other hand, the operator influences the pressure at the outlet of the respective nozzle during operation of the high-pressure cleaning device 10 with the operating unit 24 actuated. This also influences the pressure in the high-pressure line 22 and on the outlet side of the high-pressure pump 16.

As in particular from the Figures 5 to 7 shows, the high-pressure pump 16 is designed as a piston pump and in particular as an axial piston pump. The high-pressure pump 16 includes a base body 46 in which a plurality of axial pistons (an axial piston 48 shown) are mounted so as to be linearly displaceable. The drive motor 14 includes a swash plate, not shown in the drawing, whose rotation moves the axial pistons 48 .

The high-pressure pump 16 has a suction chamber 50 which is flow-connected to the pump inlet 18 or forms this. The suction chamber 50 opens into a pump chamber 52, between which a suction valve 54 is connected. Liquid that is sucked in can enter the pump chamber 52 and is pressurized therein by the axial pistons 48 .

The pump chamber 52 opens into a pressure chamber 56, with a pressure valve 58 being connected between these.

The pressure space 56 is divided into a first space 60 and a second space 62 . Liquid flowing out of the pump space 52 enters the first space 60 . Between the space areas 60, 62, a check valve 64 is used. During operation of the high-pressure pump 16, the check valve 64 can assume an open position, and liquid flows through the chambers 60 and 62 to the pump outlet 20. The pump outlet 20 is formed by the pressure chamber 56 on the outlet side or is in flow communication with it.

An advantageous embodiment of the high-pressure pump, like the high-pressure pump 16, includes a so-called overflow with an overflow valve arranged therein. In this regard, on figure 7 referred.

A control line 66 opens into the pressure chamber 56 at the second space area 62. The control line 66 can also be referred to as a control channel.

Liquid in the pressure chamber 56 can thereby apply pressure to the overflow valve 68 of an overflow valve 70 . If the high-pressure pistol 26 is no longer actuated while the high-pressure cleaning device 10 is in operation, this leads to a pressure surge via the high-pressure line 22 into the pressure chamber 56. In a manner known per se, the pressure surge via the control line 66 leads to the overflow valve 68 being acted upon leads to the overflow valve 68 opening and a valve tappet 72 of the overflow 70 being displaced.

The valve tappet 72 can actuate a switching element, not shown in the drawing, for example a microswitch. The switching element is connected to a control unit 76 of the high-pressure pump 16 via a signal line 74 . Alternatively, the switching element can be operatively connected directly to the drive motor 14 . In the presence of a switching signal, the Control unit 76 switches off the drive motor 14 via a control line 78 (or the switching element), so that the drive of the high-pressure pump 16 is deactivated when the high-pressure gun 26 is not actuated. If the high-pressure gun 26 is actuated again, the drive motor 14 is activated again.

The high-pressure cleaning device 10 comprises an admixing device 80 in order to admix a cleaning chemical to the pressurized liquid. The addition of cleaning chemicals is intended for operation with the low-pressure cleaning agent nozzles 37 and 42. The admixing device 80 on the high-pressure cleaning device 10 includes a receptacle 82 for a container 84 in which the cleaning chemical is stored. The receptacle 82 is in flow connection with the pressure chamber 56 via a supply line 86 which is partially enclosed by the base body 46 . The control line 66 preferably forms a section of the feed line 86. A check valve 88 is connected in the feed line 86, for example near the overflow 70. FIG.

The feed line 86 can also be referred to as a feed channel.

The admixing device 80 also includes an injector 90, which is designed here as a Venturi injector. The injector 90 is arranged in the pressure chamber 56, in particular in the second spatial area 62. The feed line 86 opens in the second spatial area 62 into the suction side of the injector 90.

At low pressure on the outlet side due to the large cross section of the low-pressure cleaning agent nozzles 37 and 42, the liquid pressure in the supply line 86 drops so far due to the suction effect of the injector 90 that the check valve 88 opens. In particular, the pressure in the feed line 86 is below the ambient pressure of the atmosphere (approximately less than 1 bar). The cleaning chemical can flow into the injector 90 via the supply line 86 due to the suction effect of the injector 90 and is admixed with the liquid. The mixture of liquid and cleaning chemical flows to the low-pressure cleaning agent nozzle 37, 42 and can be discharged through this.

On the other hand, if the high-pressure nozzle 39 or 44 is connected to the high-pressure gun 26, the pressure in the high-pressure line 22 and thus in the pressure chamber 56 is so high that the suction effect of the injector 90 is eliminated. The pressure in the supply line 86 is also high, the check valve 88 remains closed and no cleaning chemical is drawn in.

By connecting or selecting a low-pressure cleaning agent nozzle 37, 42, the high-pressure cleaning device 10, and in particular the high-pressure pump 16, can be switched to a cleaning agent mode. Conversely, if the high-pressure nozzle 39 or 44 is connected or selected, the high-pressure cleaning device 10 and in particular the high-pressure pump 16 assumes a high-pressure mode.

As in particular from the Figures 7 to 12 As can be seen, the high-pressure pump 16 includes a return line 92 . The pressure chamber 56 is flow-connected to the suction chamber 50 via the return line 92 . The return line 92 has a first section formed in the base body 46, which opens into the pressure chamber 56 and in particular its first spatial region 60 ( figure 8 ). A second section 96 which forms a valve chamber 98 adjoins the first section 94 . A third section 100 adjoins the valve chamber 98 and opens into the suction chamber 50 ( figure 7 ). The second and third sections 96, 100 are also formed in the base body 46.

The return line 92 can also be referred to as a return channel.

The high-pressure pump 16 includes a valve unit 102 via which the free cross-sectional area of the return line 92 can be changed. The valve unit 102 comprises a valve body receiving part 104, which is inserted into the valve chamber 98, and a valve body 106. The valve body 106 is designed as a valve pin 108.

The valve body receiving part 104 forms a valve seat 110 for the valve pin 108. The valve pin 108 can be in a closed position ( figures 9 and 11 ) on the valve seat 110 with a valve body sealing portion 112 sealingly or substantially sealingly. The return line 92 is closed.

An elastic element in the form of a helical spring 104 acts on the valve pin 108 with a force directed towards its closed position.

The high-pressure pump 16 includes a drive unit 116 which is assigned to the valve unit 102 . In the present case, the drive unit 116 is designed in particular as an electric drive unit and is electrically connected to the control unit 76 via a control line 118 . The control unit 76 can control the drive unit 116 in order to move the valve pin 108 from the closed position into at least one open position and vice versa. In particular, the valve pin 108 can be displaced in the return line 92 and relative to the valve body receiving part 104 . The valve pin 108 is moved from the closed position into the at least one open position against the closing force of the helical spring 114.

The drive unit 116 is shown in the drawing (in Figs figures 5 and 10 ) only shown schematically. For example, the drive unit 116 includes a spindle drive. The spindle drive can move a tappet 120 linearly, which is coupled to the valve pin 108 and, for example, is firmly connected to it. The tappet 120 is arranged on the side of the valve pin 108 facing away from the helical spring 114 .

The drive unit 116 can have a retaining projection 146 which engages in the base body 46 . The valve unit 102 can be held in the valve chamber 98 via the holding projection 146 . For example, the retaining projection 146 is inserted into the valve body 46 with a force fit and/or a form fit. The valve unit 102 can be supported on the retaining projection 146 against the pressure in the return line 92 acting on it.

A sealing element 148 can preferably be supported via the holding projection 146 . The sealing element 148 seals between the valve chamber 98 and the retaining projection 146. For example, the sealing element 148 is designed as an O-ring surrounding the valve pin 108.

The valve body sealing section 112 is formed, for example, on an annular collar 122 on which the coil spring 114 is supported on the opposite side.

Starting from the valve body sealing section 112, the valve pin 108 initially comprises a first, cylindrical section 124 and then a second, conical section 126. The cylindrical section 124 is dimensioned such that the valve pin 108 is arranged in the valve body receiving part 104 with some play. If the valve pin 108 lifts off the valve seat 110, liquid can flow through the return line 92.

The conical section 126 is designed to taper conically, in particular the valve pin 108 is doubly conically tapered. The taper increases with increasing distance from the valve body sealing section 112 . In the present case, this can be understood in particular to mean that the change in the diameter and thus in the cross section of the valve pin 108 increases per adjustment path or length section of the valve pin 108 . In the opposite direction to the direction for transferring the valve pin 108 from the closed position into the at least one open position, the valve pin 108 therefore has a taper which increases with increasing distance from the valve body sealing section 112 .

In particular, this makes it possible, in the at least one open position, to make the change in the free cross-sectional area of return line 92 on valve seat 110 per adjustment path of valve pin 108 relative to valve seat 110 dependent on the position of valve pin 108 relative to valve seat 110. In particular, the free cross-sectional area changes the increasing taper of the valve pin 108 with increasing distance of the valve body sealing portion 112 from the valve seat 110 to.

A further cylindrical section 128 of the valve pin 108, the diameter of which is smaller than that of the cylindrical section 124, adjoins the conical section 126 at a greater distance from the valve body sealing section 112. The sealing element 148 surrounds the cylindrical section 124.

At the valve pin 108 the liquid flows through the return line 92 axially past the valve seat 110 (in the longitudinal direction of the valve pin 108) and then downstream of the valve seat 110 radially away from the valve pin 108. The return line 92 is therefore aligned radially downstream of the valve seat 110 with respect to the longitudinal direction of the valve pin 108 . For this purpose, a passage 130 into the third section 100 is formed in the valve body receiving part 104 .

A pressure valve 132 is provided in the return line 92 downstream of the valve unit 102 . The pressure valve 132 is designed as a valve ring 134, in particular as an O-ring. The valve ring 134 surrounds the valve body receiving part 104 and can close the passage 130 and thus the return line 92 in a sealing or substantially sealing manner. If the pressure in the return line 92 exceeds a threshold pressure, the pressure valve 132 opens. If the pressure is below a threshold pressure, the return line 92 is closed.

The purpose of the pressure valve 132 is that when the high-pressure pump 16 is started up, suction operation (liquid is sucked in at the pump inlet 18 which is not connected to a pressure line) can be carried out, even if the valve pin 108 is in an open position. In this case, the pressure valve 132 prevents air from being sucked in via the return line 92 .

The high-pressure pump 16 also includes a detection unit 136. The detection unit 136 can be used to detect when a fluid pressure on the pressure side of the pump chamber 52 falls below a threshold pressure. In addition, the detection unit 136 can be used to detect when a threshold pressure is exceeded.

Preferably, falling below or exceeding a threshold pressure in the high-pressure pump 16 and preferably on or in the pressure chamber 56 can be detected, in particular in a liquid line connected to or opening into this. In an advantageous embodiment of the high-pressure pump, the detection unit 136 includes a pressure sensor 138 or is designed as such, with which the liquid pressure can be measured.

The pressure sensor 138 is arranged on the high-pressure pump 116 in such a way that a liquid pressure in the feed line 86 which opens into the pressure chamber 56 can be detected. The pressure in the supply line 86 is related to the pump pressure of the high-pressure pump 16 which is present at the pump outlet 20 . By detecting the fluid pressure in the supply line 86 at the pressure chamber 56, the pump pressure can also be inferred.

The pressure sensor 138 is connected, for example, to a measuring line 140 which is an extension of the control line 66 . The pressure sensor 138 is connected to the control unit via a signal line 142 in order to provide it with a signal corresponding to the liquid pressure. The measuring line 140 can also be referred to as a measuring channel.

The functioning of the high-pressure cleaning device 10 and the high-pressure pump 16 is explained below.

As mentioned, a high-pressure mode is provided on the one hand and a detergent mode on the other. In the high-pressure mode, the fluid pressure that can be detected by the pressure sensor 108 in the pressure chamber 56 is regulated. In detergent mode the valve unit 102 is activated in order to control the volume flow of the liquid to be dispensed and thus to control the dosing of the cleaning chemical.

If a high-pressure nozzle 39 or 44 is connected or selected, a high pressure prevails in the pressure chamber 56 and thus also in the feed line 86 when the operating unit 24 is actuated. The operator uses the "+" 30 and "-" 32 keys to specify a pressure level. Each pressure step corresponds to a pump pressure at the pump outlet 20 and thus to a fluid pressure in the supply line 86 related to this.

figure 3 shows, by way of example, the display unit 34 in the high-pressure mode in various pressure stages which decrease from top to bottom. A total of six different pressure levels are provided, which the operator can select using buttons 30 and 32 . Pressing the "+" button 30 increases the pressure and pressing the "-" button 32 decreases the pressure.

The specification of the operator is wirelessly transmitted from the input unit 28 to the control unit 76 coupled to it. The control unit 76 actuates the drive unit 116. Depending on the specification by the operator, the liquid pressure, which is detected by the pressure sensor 138, is regulated by actuating the drive unit 116. The high-pressure cleaning device 10 and in particular the high-pressure pump 16 assumes a control mode.

The controller 76 may determine that the high pressure mode has been entered by the pressure sensor 138 detecting a fluid pressure in the supply line 86 that is above a threshold pressure. When the high-pressure mode is assumed, a symbol 143 of a high-pressure nozzle, for example, is displayed on the display unit 34 . Also displayed is information that is associated with the specification by the operator. These are representations of the pressure levels symbolized by black lines or bars.

Information for changing the display unit 34 can be transmitted wirelessly from the control unit 76 to the display unit 34 coupled to it.

At the highest pressure level (above in figure 3 ) the return line 92 is closed, for example, and the valve body sealing section 112 is in sealing contact with the valve seat 110 ( figures 9 and 11 ). By reducing the pressure level, the position of the valve unit 112 is changed in that the valve pin 118 is transferred to an open position. This increases the free cross-sectional area of the return line 92, liquid flows from the pressure chamber 56 to the suction chamber 50, and the pump pressure at the pump outlet 20 is reduced. This is detected via the pressure in the feed line 86 . The pressure in the feed line 86 is regulated by controlling the drive unit 116 .

The same applies to a further reduction in the pressure levels, with the valve pin 108 being transferred to an open position, depending on the pressure level, in which the free cross-sectional area of the return line 92 increases further, the volume flow through the return line 92 is increased and the pump pressure at the pump outlet 20 is reduced. The liquid pressure is regulated in the respective pressure stage.

If the valve pin 108 is moved into an open position, the pressure valve 132 opens so that a flow through the return line 92 is released.

In the control mode, the valve pin 108 is not pushed by the drive unit 116 by the entire possible adjustment path to implement the lowest pressure level. The valve pin 108 is displaced, for example, only to the extent of the conical section 126 following the cylindrical section 124 to the extent that the conicity of the section 126 does not change. This corresponds to the range of constant tapering of the conical section 126 and a change in the free cross-sectional area of the return line 92 per adjustment path, which is constant.

If a low-pressure cleaning agent nozzle 37 or 42 is connected or selected, the large opening cross-section leads to a pressure drop in the supply line 86 when the control unit 24 is actuated. The control unit 76 analyzes the signal from the pressure sensor 138 and can determine that the detergent nozzle 37 or 42 is being used. The control unit 76 switches to a detergent mode. An indication of this is transmitted wirelessly to the display unit 34 . In particular, an icon 144 for a low pressure detergent nozzle is shown.

The display unit 34 changes the image display from that in figure 3 shown high-pressure mode in the in figure 4 detergent mode shown.

In the detergent mode, the high-pressure cleaning device 10 and in particular the high-pressure pump 16 assumes a non-regulating mode. The fluid pressure sensed by pressure sensor 138 is no longer regulated.

Instead, the operator controls the position of the valve unit 102 using the "+" 30 and "-" 32 keys. This has the particular consequence that the free cross-sectional area of the return line 92 and the volume flow through it are controlled by the operator.

In the non-regulation mode, the valve unit 102 opens and the volume flow at the pump outlet 20 changes due to the increasing volume flow through the return line 92. Since the cleaning chemical is sucked into the injector 90 via the supply line 86 at the same time, the mixing ratio between the liquid and the cleaning chemical changes.

The operator can use the buttons 30 and 32 to gradually change the mixing ratio. A total of three different mixing ratios can be set in stages, figure 4 shows in this regard the respective image display of the Display unit 34. Different mixing ratios are symbolized, for example, by a different number of lines or bars. up in figure 4 the situation of maximum dosing of the cleaning chemical is shown, ie a high mixing ratio of the cleaning chemical with the liquid (high proportion of the cleaning chemical). The mixing ratio of the cleaning chemical decreases downwards.

In the Figures 3 and 4 it can also be seen that the image display of the display unit 34 is at least partially "inverted" in the high-pressure mode and in the detergent mode. While in the high-pressure mode the pressure levels are symbolized by bars with spaces between them, in the detergent mode bars displayed in these spaces symbolize the mixing ratio of the cleaning chemical with the liquid.

The user specification on the keys 30 and 32 is implemented by the control unit 76 to control the drive unit 116 . The drive unit 116 moves the valve pin 108 to such an extent that the free cross-sectional area of the return line 92 is changed depending on the selected dosage of cleaning chemicals (mixing ratio).

In the Figures 3 and 4 it can also be seen that the representation on the display unit 34 for the pressure stage on the one hand ( 3 ) and the mixing ratio on the other hand ( 4 ) reflects opposite positions of the valve assembly 102 and associated free cross-sectional areas of the return line 92. In the high-pressure mode, the valve unit 102 is at high pressure stage (above in 3 ) closed, at low pressure level (below in 3 ) opened. In detergent mode, on the other hand, at high levels of detergent chemical (above in 4 ) more open than required at low levels of detergent chemical (below in 4 ) the case is.

In particular, the valve pin 108 is moved in the detergent mode so far that the change in the free cross-sectional area over the increasing Rejuvenation of the conical section 126 takes place. The free cross-sectional area therefore changes to a greater extent per adjustment path of the valve body 106 than is the case per adjustment path in the high-pressure mode.

If a high-pressure nozzle 39 or 44 is connected or selected again, when the operating unit 24 is actuated, the pressure sensor 138 again detects that the pressure in the supply line 86 again exceeds the first-mentioned threshold pressure. The high-pressure cleaning device 10 switches to the high-pressure mode already explained.

The threshold pressures above which the high-pressure mode and below which the detergent mode is detected can preferably be identical.

The geometry of the valve pin 108, which in particular has a double-conical section 126, makes it possible to reliably ensure the different setting of the pressure stages and the regulation of the fluid pressure in the high-pressure mode. In the cleaning agent mode, the geometry of the volume flow of the liquid through the return line 92 and thus the mixing ratio of the cleaning chemical with the liquid can be reliably adjusted. Therefore, the division of the "control band" for the high pressure mode and the "control band" of the valve pin 108 allows reliable operation of the high pressure pump 16 in both the modulating and non-modulating modes.

The high-pressure cleaning device 10 and the high-pressure pump 16 make it possible, depending on the respectively selected or connected discharge unit, to switch to regulating the liquid pressure or controlling the dosage (mixing ratio) of the cleaning chemical. The input unit 28 for selecting the pressure stage or for selecting the mixing ratio is identical. Depending on the operating mode, the display unit 34 shows the pressure levels or the levels for the mixing ratio. The high-pressure cleaning device 10 is therefore also characterized by a particularly user-friendly and intuitive operation.

Alternatively or in addition to the return line 86 and the valve unit 102 and the drive unit 116, it can be provided that the high-pressure pump has a valve 150 via which the metering of the cleaning chemical and thus the mixing ratio with the liquid can be influenced. Such a metering valve 150 is connected, for example, in the feed line 86 . figure 7 shows an example of the arrangement of the metering valve 150, preferably upstream of the check valve 88 in the direction of flow of the cleaning chemical.

The metering valve 150 may be manually operable or adjustable. It is also conceivable for metering valve 150 to be actuated by control unit 76 as a function of the operator's specification on input unit 28.

In the high-pressure cleaning device 10, the liquid pressure is preferably only regulated in the high-pressure mode when the drive motor 14 is in operation. This can be determined by the control unit 76, for example. This can prevent unnecessary pressure regulation from taking place when the drive motor 14 is switched off and the fluid pressure detected by the pressure sensor 138 changes as a result.

Correspondingly, the operating mode is switched between the high-pressure mode and the cleaning agent mode and vice versa, preferably only when the drive motor 14 is in operation, as is the operating mode-dependent content of the display unit 34.

1. 1. Hochdruckreinigungsgerät mit einer Hochdruckpumpe (16), umfassend einen Saugraum (50), mindestens einen diesem nachgelagerten Pumpraum (52), in dem Flüssigkeit unter Druck gesetzt wird, und einen dem Pumpraum (52) nachgelagerten Druckraum (56), wobei das Hochdruckreinigungsgerät (10) eine Bedieneinheit (24) aufweist, an der bzw. an die eine Austragseinheit (36, 41) in Gestalt einer Niederdruck-Reinigungsmitteldüse (37, 42) angeordnet oder angeschlossen ist und die über eine Hochdruckleitung (22) mit dem Druckraum (56) in Strömungsverbindung bringbar ist, sowie eine Beimischeinrichtung (80), über die der Flüssigkeit im Druckraum (56) eine Reinigungschemikalie beimischbar ist, dadurch gekennzeichnet, dass das Hochdruckreinigungsgerät (10) eine Erfassungseinheit (136) aufweist, mit der erfassbar ist, dass ein Flüssigkeitsdruck druckseitig des Pumpraumes (52) einen Schwellenwertdruck unterschreitet, eine mit der Erfassungseinheit (136) gekoppelte Steuereinheit (76), eine mit der Steuereinheit (76) gekoppelte Hinweiseinheit (34), an der ein Hinweis für eine Bedienperson bereitstellbar ist, dass das Hochdruckreinigungsgerät (10) einen Reinigungsmittelmodus einnimmt, sowie eine Eingabeeinheit (28), über die von der Bedienperson ein Mischverhältnis der Reinigungschemikalie mit der Flüssigkeit vorgebbar ist.
2. 2. Hochdruckreinigungsgerät nach Satz 1, dadurch gekennzeichnet, dass mit der Erfassungseinheit (136) das Unterschreiten eines Schwellenwertdruckes am oder im Druckraum (56) erfassbar ist.
3. 3. Hochdruckreinigungsgerät nach Satz 1 oder 2, dadurch gekennzeichnet, dass das Mischverhältnis stufenweise und/oder kontinuierlich vorgebbar ist.
4. 4. Hochdruckreinigungsgerät nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass die Hinweiseinheit eine Anzeigeeinheit (34) ist oder umfasst.
5. 5. Hochdruckreinigungsgerät nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass die Eingabeeinheit (28) und die Anzeigeeinheit (34) eine integrierte Eingabe-/Anzeigeeinheit bilden oder als solche ausgestaltet sind.
6. 6. Hochdruckreinigungsgerät nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass an der Hinweiseinheit eine Information betreffend das Mischverhältnis bereitstellbar ist, insbesondere dass dies an einer Anzeigeeinheit (34) darstellbar ist.
7. 7. Hochdruckreinigungsgerät nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass die Eingabeeinheit (28) und/oder die Hinweiseinheit an der Bedieneinheit (24) angeordnet oder von dieser umfasst sind.
8. 8. Hochdruckreinigungsgerät nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass Informationen von der Eingabeeinheit (28) an die Steuereinheit (76) und/oder von der Steuereinheit (76) an die Hinweiseinheit (34) kabellos übertragbar sind.
9. 9. Hochdruckreinigungsgerät nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass über die Eingabeeinheit (28) ein Volumenstrom der mit der Hochdruckpumpe (16) geförderten Flüssigkeit steuerbar ist.
10. 10. Hochdruckreinigungsgerät nach Satz 9, dadurch gekennzeichnet, dass die Hochdruckpumpe (16) eine Rückführleitung (92) umfasst, über die der Druckraum (56) mit dem Saugraum (50) in Strömungsverbindung steht, und eine Ventileinheit (102), mit der eine freie Querschnittsfläche der Rückführleitung (92) veränderbar ist, eine der Ventileinheit (102) zugeordnete und mit der Steuereinheit (76) gekoppelte Antriebseinheit (116), wobei der Volumenstrom steuerbar ist, indem abhängig vom vorgegebenen Mischverhältnis die freie Querschnittsfläche der Rückführleitung (92) veränderbar ist.
11. 11. Hochdruckreinigungsgerät nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass die Beimischeinrichtung (80) eine Aufnahme (82) für einen Behälter (84) mit der Reinigungschemikalie aufweist, einen im Druckraum (56) angeordneten Injektor (90) und eine Zuführleitung (86) von der Aufnahme zum Injektor (90).
12. 12. Hochdruckreinigungsgerät nach Satz 11, dadurch gekennzeichnet, dass mit der Erfassungseinheit (136) erfassbar ist, ob der Flüssigkeitsdruck in der Zuführleitung (86) den Schwellenwertdruck unterschreitet.
13. 13. Hochdruckreinigungsgerät nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass die Erfassungseinheit (13) einen Drucksensor (138) oder einen Druckschalter umfasst.
14. 14. Hochdruckreinigungsgerät nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass das Hochdruckreinigungsgerät (10) im Reinigungsmittelmodus einen Nichtregelungsmodus einnimmt, in dem keine Regelung des Flüssigkeitsdruckes erfolgt.
15. 15. Hochdruckreinigungsgerät nach einem der voranstehenden Sätze, dadurch gekennzeichnet, dass das Hochdruckreinigungsgerät (10) eine weitere Austragseinheit (38, 43) in Gestalt einer Hochdruckdüse (39, 44) aufweist, die anstelle der Niederdruck-Reinigungsmitteldüse (37, 42) an die Bedieneinheit (24) anschließbar oder an dieser anordenbar ist, und dass mit der Erfassungseinheit (136) erfassbar ist, dass der Flüssigkeitsdruck druckseitig des Pumpraumes (52) einen Schwellenwertdruck überschreitet, wobei an der Hinweiseinheit ein Hinweis bereitstellbar ist, dass das Hochdruckreinigungsgerät (10) einen Hochdruckmodus einnimmt.
16. 16. Hochdruckreinigungsgerät nach Satz 15, dadurch gekennzeichnet, dass der Steuereinheit (76) von der Bedienperson über die Eingabeeinheit (28) ein Flüssigkeitsdruck vorgebbar ist, wobei der Flüssigkeitsdruck von der Steuereinheit (76) steuerbar ist.
17. 17. Hochdruckreinigungsgerät nach Satz 16, dadurch gekennzeichnet, dass der Flüssigkeitsdruck stufenweise und/oder kontinuierlich vorgebbar ist.
18. 18. Hochdruckreinigungsgerät nach Satz 16 oder 17 in Verbindung mit Satz 10, dadurch gekennzeichnet, dass der Flüssigkeitsdruck abhängig vom vorgegebenen Flüssigkeitsdruck unter Veränderung der freien Querschnittsfläche der Rückführleitung (92) steuerbar ist.
19. 19. Hochdruckreinigungsgerät nach einem der Sätze 16 bis 18, dadurch gekennzeichnet, dass das Hochdruckreinigungsgerät (10) im Hochdruckmodus einen Regelungsmodus einnimmt, in dem eine Regelung des Flüssigkeitsdruckes erfolgt.
20. 20. Hochdruckreinigungsgerät nach einem der Sätze 16 bis 19, dadurch gekennzeichnet, dass die Hinweiseinheit eine Anzeigeeinheit (34) ist, an der der Bedienperson eine dem vorgegebenen Flüssigkeitsdruck zugeordnete Information anzeigbar ist.
21. 21. Hochdruckreinigungsgerät nach einem der Sätze 15 bis 20, dadurch gekennzeichnet, dass die Eingabeeinheit (28) Eingabeelemente (30, 32) umfasst, mit denen bei Vorliegen des Reinigungsmittelmodus das Mischverhältnis vorgebbar und bei Vorliegen des Hochdruckmodus der Flüssigkeitsdruck vorgebbar ist.

The above description includes in particular the disclosure of the embodiments of a high-pressure cleaning device according to the invention, which are defined using the following sentences:

1. 1. High-pressure cleaning device with a high-pressure pump (16), comprising a suction space (50), at least one pump space (52) downstream of this, in which liquid is pressurized, and a pressure space (56) downstream of the pump space (52), the high-pressure cleaning device (10) has an operating unit (24) on which or to which a discharge unit (36, 41) in the form of a low-pressure cleaning agent nozzle (37, 42) is arranged or connected and which is connected to the pressure chamber ( 56). a fluid pressure on the pressure side of the pump chamber (52) falls below a threshold pressure, a control unit (76) coupled to the detection unit (136), a control unit to the control Unit (76) coupled notification unit (34), on which a notification can be provided to an operator that the high-pressure cleaning device (10) is in cleaning agent mode, and an input unit (28), via which the operator can specify a mixing ratio of the cleaning chemicals with the liquid is.
2. 2. High-pressure cleaning device according to sentence 1, characterized in that the falling below a threshold pressure at or in the pressure chamber (56) can be detected with the detection unit (136).
3. 3. High-pressure cleaning device according to sentence 1 or 2, characterized in that the mixing ratio can be predetermined in stages and/or continuously.
4. 4. High-pressure cleaning device according to one of the preceding sentences, characterized in that the information unit is or comprises a display unit (34).
5. 5. High-pressure cleaning device according to one of the preceding sentences, characterized in that the input unit (28) and the display unit (34) form an integrated input/display unit or are designed as such.
6. 6. High-pressure cleaning device according to one of the preceding sentences, characterized in that information relating to the mixing ratio can be provided on the notification unit, in particular that this can be displayed on a display unit (34).
7. 7. High-pressure cleaning device according to one of the preceding sentences, characterized in that the input unit (28) and/or the notification unit are arranged on the operating unit (24) or are encompassed by it.
8. 8. High-pressure cleaning device according to one of the preceding sentences, characterized in that information can be transmitted wirelessly from the input unit (28) to the control unit (76) and/or from the control unit (76) to the notification unit (34).
9. 9. High-pressure cleaning device according to one of the preceding sentences, characterized in that via the input unit (28) a volume flow of the high-pressure pump (16) funded liquid can be controlled.
10. 10. High-pressure cleaning device according to sentence 9, characterized in that the high-pressure pump (16) comprises a return line (92) via which the pressure chamber (56) is in flow communication with the suction chamber (50), and a valve unit (102) with which one free cross-sectional area of the return line (92) can be changed, a drive unit (116) assigned to the valve unit (102) and coupled to the control unit (76), the volume flow being controllable by depending on the specified Mixing ratio, the free cross-sectional area of the return line (92) is variable.
11. 11. High-pressure cleaning device according to one of the preceding sentences, characterized in that the admixing device (80) has a receptacle (82) for a container (84) with the cleaning chemical, an injector (90) arranged in the pressure chamber (56) and a feed line (86 ) from the receptacle to the injector (90).
12. 12. High-pressure cleaning device according to sentence 11, characterized in that the detection unit (136) can be detected as to whether the liquid pressure in the supply line (86) falls below the threshold pressure.
13. 13. High-pressure cleaning device according to one of the preceding sentences, characterized in that the detection unit (13) comprises a pressure sensor (138) or a pressure switch.
14. 14. High-pressure cleaning device according to one of the preceding sentences, characterized in that the high-pressure cleaning device (10) assumes a non-regulation mode in the detergent mode, in which there is no regulation of the liquid pressure.
15. 15. High-pressure cleaning device according to one of the preceding sentences, characterized in that the high-pressure cleaning device (10) has a further discharge unit (38, 43) in the form of a high-pressure nozzle (39, 44) which, instead of the low-pressure cleaning agent nozzle (37, 42), is attached to the Operating unit (24) can be connected or arranged on it, and that the detection unit (136) can detect that the liquid pressure on the pressure side of the pump chamber (52) exceeds a threshold pressure, with a message being able to be provided on the notification unit that the high-pressure cleaning device (10) assumes a high-pressure mode.
16. 16. High-pressure cleaning device according to sentence 15, characterized in that the control unit (76) can be predetermined by the operator via the input unit (28) a fluid pressure, the fluid pressure being controllable by the control unit (76).
17. 17. High-pressure cleaning device according to sentence 16, characterized in that the liquid pressure can be predetermined in stages and/or continuously.
18. 18. High-pressure cleaning device according to clause 16 or 17 in conjunction with clause 10, characterized in that the liquid pressure can be controlled as a function of the predetermined liquid pressure by changing the free cross-sectional area of the return line (92).
19. 19. High-pressure cleaning device according to one of sentences 16 to 18, characterized in that the high-pressure cleaning device (10) assumes a control mode in the high-pressure mode in which the liquid pressure is controlled.
20. 20. High-pressure cleaning device according to one of sentences 16 to 19, characterized in that the notification unit is a display unit (34) on which the operator can display information associated with the predetermined liquid pressure.
21. 21. High-pressure cleaning device according to one of sentences 15 to 20, characterized in that the input unit (28) comprises input elements (30, 32) with which the mixing ratio can be specified when the detergent mode is present and the liquid pressure can be specified when the high-pressure mode is present.

Claims (15)

High-pressure cleaning device with a high-pressure pump (16), comprising a suction space (50), at least one pump space (52) downstream of this, in which liquid is pressurized, and a pressure space (56) downstream of the pump space (52), the high-pressure cleaning device (10 ) has an operating unit (24) on which or to which a discharge unit (36, 41) in the form of a low-pressure cleaning agent nozzle (37, 42) is arranged or connected and which is connected to the pressure chamber (56) via a high-pressure line (22) can be brought into flow connection, and an admixing device (80) via which a cleaning chemical can be admixed to the liquid in the pressure chamber (56), characterized in that the high-pressure cleaning device (10) has a detection unit (136), which in particular has a pressure sensor (138) or comprises a pressure switch and with which it can be detected that a liquid pressure on the pressure side of the pump chamber (52) falls below a threshold pressure, one with which A control unit (76) coupled to the detection unit (136), a notification unit (34) coupled to the control unit (76), on which a notification can be provided to an operator that the high-pressure cleaning device (10) is in a cleaning agent mode, and an input unit (28), via which the operator can specify a mixing ratio of the cleaning chemical with the liquid. High-pressure cleaning device according to Claim 1, characterized in that the fact that the pressure falls below a threshold value at or in the pressure chamber (56) can be detected by the detection unit (136). High-pressure cleaning device according to Claim 1 or 2, characterized in that the mixing ratio can be predetermined in stages and/or continuously. High-pressure cleaning device according to one of the preceding claims, characterized in that the notification unit is or includes a display unit (34) and/or that the input unit (28) and the display unit (34) form an integrated input/display unit or are designed as such. High-pressure cleaning device according to one of the preceding claims, characterized in that information relating to the mixing ratio can be provided on the notification unit, in particular that this can be displayed on a display unit (34). High-pressure cleaning device according to one of the preceding claims, characterized in that at least one of the following applies: - the input unit (28) and/or the indication unit are arranged on the operating unit (24) or are comprised by this; - Information can be wirelessly transmitted from the input unit (28) to the control unit (76) and/or from the control unit (76) to the notification unit (34). High-pressure cleaning device according to one of the preceding claims, characterized in that the input unit (28) can be used to control a volume flow of the liquid delivered by the high-pressure pump (16), preferably in that the high-pressure pump (16) comprises a return line (92) via which the pressure chamber ( 56) is flow-connected to the suction chamber (50), and a valve unit (102) with which a free cross-sectional area of the return line (92) can be changed, a drive unit (116 ), the volume flow being controllable in that the free cross-sectional area of the return line (92) can be changed depending on the predetermined mixing ratio. High-pressure cleaning device according to one of the preceding claims, characterized in that the admixing device (80) has a receptacle (82) for a container (84) with the cleaning chemical, an injector (90) arranged in the pressure chamber (56) and a feed line (86) from the receptacle for the injector (90), preferably that the detection unit (136) can be used to detect whether the liquid pressure in the supply line (86) falls below the threshold pressure. High-pressure cleaning device according to one of the preceding claims, characterized in that the high-pressure cleaning device (10) assumes a non-regulation mode in the detergent mode, in which there is no regulation of the liquid pressure. High-pressure cleaning device according to one of the preceding claims, characterized in that the high-pressure cleaning device (10) has a further discharge unit (38, 43) in the form of a high-pressure nozzle (39, 44) which, instead of the low-pressure cleaning agent nozzle (37, 42), is connected to the operating unit ( 24) can be connected or arranged thereon, and that the detection unit (136) can detect that the liquid pressure on the pressure side of the pump chamber (52) exceeds a threshold pressure, with an indication being able to be provided on the notification unit that the high-pressure cleaning device (10) is in a high-pressure mode occupies, preferably that the control unit (76) can be specified by the operator via the input unit (28) a fluid pressure, wherein the fluid pressure can be controlled by the control unit (76). High-pressure cleaning device according to Claim 10, characterized in that the liquid pressure can be predetermined in stages and/or continuously. High-pressure cleaning device according to Claim 10 or 11 in conjunction with Claim 7, characterized in that the liquid pressure is dependent can be controlled by the predetermined liquid pressure while changing the free cross-sectional area of the return line (92). High-pressure cleaning device according to one of Claims 10 to 12, characterized in that in the high-pressure mode the high-pressure cleaning device (10) assumes a control mode in which the liquid pressure is controlled. High-pressure cleaning device according to one of Claims 10 to 13, characterized in that the notification unit is a display unit (34) on which information associated with the predetermined liquid pressure can be displayed to the operator. High-pressure cleaning device according to one of Claims 10 to 14, characterized in that the input unit (28) comprises input elements (30, 32) with which the mixing ratio can be specified when the detergent mode is present and the liquid pressure can be specified when the high-pressure mode is present.

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