DE10146289A1 - Method for controlling the pressure in a pressurised water cleaning machine has a pressure sensor and microprocessor to switch the electric motor. - Google Patents

Abstract

The pressure pump (6) is driven by an electric motor (7) and delivers pressurised water through a hose (4) to a pistol jet (3). A pressure sensor (DS) is placed in the line at a convenient location and the pressure is compared by a computer control unit (1) to switch the motor on or off.

Description

The invention relates to a method for controlling a High-pressure cleaning device, which has a high-pressure pump that has a Suction line is fed from a liquid supply network. Furthermore, a Pressure sensor provided that an operating pressure within the High-pressure cleaning device records and measured values of a control on the output side which feeds the pump depending on the measured operating pressure off. The measured operating pressure with a preset lower and a preset upper pressure threshold compared, and if the value falls below the lower threshold, the pump the pump is switched on and when the upper threshold is exceeded switched off. The invention also relates to a computer program Program code elements for a control computer for executing the aforementioned control method. The invention further relates to a Control arrangement for the operating pressure in a high-pressure cleaning device with a motor-driven high-pressure pump and with at least one, spray gun directly connected to the pressure outlet of the pump and with at least one pressure sensor, the output of which is connected to an electronic one Control unit is connected, the output side of an actuator for Drive motor of the pump controls. Finally, the invention relates to one Kit for upgrading a high-pressure cleaning device to the named Form arrangement, connecting means, for example in the form of a Slot or slot for one electronic control unit and one Pressure sensor are provided.

EP 0 892 174 A2 describes a high-pressure cleaning device which is used for Control and regulation of the pumping process on a microcomputer Control board can have.

DE 39 02 252 C1 describes a high-pressure cleaning device with one of one Internal combustion engine-driven high-pressure pump described in the Pressure line a pressure sensor is arranged. Between the pressure sensor and the pressure outlet of the pump is a closing valve for a bypass arrangement in Connection with a suction line and a storage vessel inserted. The  Pressure sensor is connected directly to the throttle lever via a Bowden cable Internal combustion engine connected.

JP 07 167 102 A describes a pressure control method for a high pressure pump known about the type mentioned. From a liquid supply or Accumulator are three in connection with a high pressure pump Ejection nozzles fed at the same time. The accumulator serves Pressure fluctuations as a buffer and is at its the nozzles and the High pressure pump distal or opposite end with a pressure sensor provided, the measurement signals detected and evaluated by a controller become. The control operates the pump when the frequency of changes of the pressure does not fall below a certain threshold, and if the measured internal pressure below a threshold between an upper and Lower limit is sufficient. It is therefore dependent on the internal pressure of the battery or Liquid reservoir and the pressure fluctuation frequency High pressure pump actuated to pressure drops when dispensed Suppress liquid jet.

In contrast, the invention is based on the object To develop control methods for a high-pressure cleaning device, which with a minimum number of components and functional components based on Operating pressure of the available liquid supply network one easy operation and operation of the high-pressure cleaning device with high Operational reliability allowed. In particular, the number of necessary mechanical components and thus in mass production Production costs are minimized. At the same time, the control procedure versatile and especially different for a large number executed high-pressure cleaning devices can be applicable.

The solution to this is a control method with the aforementioned Features proposed according to the invention that by means of the pressure sensor Operating pressure constantly directly in the area of a pressure outlet of the pump or is detected directly via a pressure channel emanating from this pressure outlet. One advantage achieved in this way is that the control method is its Control commands for the pump directly based on the actual pressure values  determined at the pump outlet, whereby the high-pressure cleaning device from the Operator immediately about opening and closing the print output of the Control the high pressure pump or set it to the desired conditions. Further advantageous configurations result from the dependent ones Claims.

A special embodiment of the method according to the invention consists in that the lower threshold in the low pressure area of the supply network and the upper threshold in the high pressure area of the pressure outlet of the Pump is placed. By constantly evaluating the operating pressure and on the one hand is compared with the supply network outgoing supply pressure a simple and reliable way to switch on the Win high pressure pump. The same applies to pump operation and Exceeding the upper threshold for switching off. Special mechanical components are for switching the high pressure pump on and off and no longer necessary for pressure control. In practice, have proven to be appropriate values for presetting the lower threshold Pressure range from 0.1 bar to 25 bar and for the upper threshold Proven pressure range from 200 bar to 2500 bar.

The method according to the invention opens up the advantageous possibility of the operating pressure by simply pressing or releasing the Control lever of a high pressure gun, which one manually actuatable nozzle forms at the end of a pressure line of the high pressure pump. This is expediently accomplished in that the operating pressure Actuate one or more spray guns that are connected to the pressure outlet of the Pump are connected until the value falls below the lower threshold is lowered.

The state of the art when using mechanical components associated wear, for example on control valves due to soiled Water, calcifications, etc. is avoided by means of the invention. Due to the minimized number of necessary construction components  Control method easily on high pressure cleaners of different types adapt. In the case of mass production, the production costs are very low expected.

Within the general inventive idea also lies Computer program with program code elements for a control, in particular microcomputer, which is the execution of the control process can serve as soon as the program is loaded into the microcomputer control and is started on it. The computer program is expediently located in one electrically programmable storage device that acts as a program disk for the microcomputer or another programmable controller can be used.

In particular, the operating pressure in the area relevant to operation or can be detected in the direction of the high-pressure spray gun, is based the general inventive idea in a control arrangement for the Operating pressure in a high pressure cleaning device with the above Features proposed according to the invention that the pressure sensor in one Section of the high-pressure cleaning device is arranged, where a pump Operating pressure extends directly from the pressure outlet to the spray gun. So that's the aforementioned training of the process invention, on the operation of Spray gun to control the high pressure washer, especially bill carried. The operating pressure prevailing in the vicinity of the spray gun becomes namely precisely and reliably detected with the entire arrangement. From that starting from can be functionally appropriate by the control device Derive or calculate times at which the pump drive engages or is to be switched off.

A particularly space-saving and mechanically firm attachment of the In one embodiment of the invention, the pressure sensor is the pressure sensor in or to attach to a pressure manifold, especially if it is Pressure manifold in a housing block of a so-called pump head (cf. EP 0 892 174 A2). Alternatively, the pressure sensor can also be switched on or install inside the spray gun or its supply pressure hose.  

The pump drive motor with an electric motor is particularly advantageous realized, since this is directly by switching on and off a Start up or stop the power supply network. Accordingly the actuator with on or off elements in particular in the form of electrically controlled contactors implemented.

In order to be able to adapt conventional high-pressure cleaners of different types as easily as possible to form the arrangement according to the invention, the kit with the features mentioned at the beginning is proposed, which also has the following components:

• - A pressure sensor, both for the low pressure range of the Supply network as well as for the high pressure area of the pressure outlet the high pressure pump is designed (find suitable pressure sensor principles already used in automotive engineering),
• - An electronic assembly carrying the control unit, which is used for coupling the connection means of the high-pressure cleaning device formed and with a Interface to the pressure sensor is provided.

After a special invention training, the kit can still Comprise actuator for actuating a drive motor of the high pressure pump, a corresponding interface to the Control of the actuator is provided. Especially when the drive motor the high pressure pump is realized with an electric motor, is according to one further invention training the use of an electromagnetically actuated Switch, in particular contactors, for switching the drive motor on and off appropriate. With particular advantage, especially to achieve a compact or space-saving design, is the actuator or that for the electric motor contactor provided on the electronics module.

Further details, features, advantages and effects based on the Invention result from the following description more preferred Embodiments of the invention and from the drawings. These show in:  

Fig. 1, a high-pressure cleaning apparatus in perspective view;

Fig. 2 is a partial axial longitudinal sectional view of the pump head with driving means,

Fig. 3 is a block diagram of the high-pressure cleaning device according to the invention,

Fig. 4 is a structural diagram of the control arrangement according to the invention for the high-pressure cleaning device, and

Fig. 5 is a flowchart of the process sequence according to the invention.

For illustration, a cleaning device working with high pressure water is shown in FIG. 1. Various parameters can be set, called up or read on a display 2 from a control switch box 1 , in which a microcomputer can be accommodated to take over the complete control and regulation of the pump process. The cleaning water is sprayed out of the spray gun 3 , which is connected via a flexible pressure hose 4 to the pump head 5 of a high-pressure pump 6 with drive motor 7 . According to the invention, a pressure sensor DS is arranged on the pump head 5 , on the pressure hose 4 (for example via a T-link 51 ) and / or in the region of the spray gun 3 . Furthermore, the control switch box is provided with a connection point or a slot for an electronic module (not shown), which is explained below in particular with reference to FIG. 4.

The structure of a pump head shown in FIG. 2 is explained by means of the list of reference symbols below and is already known to the person skilled in the art, for example, from the above-mentioned patent publication EP 0 892 174 A2. The suction manifold 32 (shown in broken lines) is connected to a liquid source (not shown), in particular a water supply network. Depending on the concern of the pressure difference, triggered by water line pressure from the suction manifold 32 and the suction line 31 within the receiving body 8 on the one hand and the suction valve spring 28 on the other hand, the suction line 31 is opened or closed. A plug-in tube 39 in the receiving body 8 forms the end or pressure outlet 40 of the pump head, which opens into the pressure collection channel for transmission to the spray gun 3 . Water previously sucked in is pressed through the central pressure line 33 onto the pressure valve ball 34 until it detaches from the opposing metallic sealing surfaces 37 at the end of the pressure line 33 against the force of the pressure valve spring 35 . Water under extremely high pressure can reach the pressure collection channel 41 through the pressure outlet 40 . The operating pressure prevailing there is detected according to the invention with a pressure sensor DS which, according to the example shown, is arranged in the pressure collecting duct 41, which is directly connected to the pressure outlet 40 .

The basic principle according to the invention is further illustrated with reference to FIG. 3. From a storage vessel 50 for cleaning liquid, in particular water, the liquid enters the pump 6 via the suction line 31 . From there it is conveyed to the spray gun 3 via a pressure channel, for example designed as the pressure hose 4 shown in FIG. 1. The pressure sensor DS coupled to the pressure channel via the T member 51 detects the operating pressure prevailing between the pump 6 and the spray gun 3 and outputs corresponding measurement signals to a control unit C. This processes the corresponding measured values, in particular after prior digitization, from which actuating signals 52 for a contactor 53 are generated. By actuating it, the electrically implemented drive motor 7 is connected to a three-phase power supply network, for example, and switched on in the process. When the pump 6 is switched on, it is started to generate the operating pressure detected by the pressure sensor DS.

So that as many common high-pressure cleaning devices as possible, preferably with an electric drive, can be upgraded by means of the electronic pressure cut-off (via pressure sensor DS, control C, contactor 53 , motor 7 and pump 6 ), an upgrade kit according to FIG. 4 is provided according to the invention, which consists of the electronics module 54 and the pressure sensor DS. In addition to a power supply unit 55 with an on / off switch 56 for coupling to the power supply network, the electronics module 54 comprises, as a central core, a microcomputer μR with at least one memory module S in a known manner, which in particular contains program code elements for executing the control method according to the invention according to FIG. 5. Furthermore, the electronics module 54 includes a sensor interface SI as an interface to the pressure sensor DS, which is designed so that it measures the sensor interface with sufficient accuracy both in the low pressure range corresponding to the water supply network and in the high pressure range in accordance with the pump output power SI transmitted. There they are digitized in such a way that they can be processed further by the microcomputer µR in accordance with the control algorithm according to FIG. 5. Switch signals 57 are supplied to contactor 53 via an actuator interface AI on electronics module 54 in accordance with the result of the control algorithm. According to the exemplary embodiment according to FIG. 4, this is likewise arranged on the electronic assembly 54 .

Referring to FIG. 5, the controller or the microcomputer uR passes after actuation of the power switch 56 for the power supply unit 55 carries out a self test 57th If it exists, the microcomputer executes a query routine 58 in order to read in and digitize measured values of the pressure sensor DS via the sensor interface SI. The display 2 , which can also be accommodated on the electronics module 54 (according to FIG. 4), is actuated by the microcomputer μR to display the measured operating pressure. In a subsequent comparison routine 59 , it is determined whether the measured operating pressure corresponds to the pressure range of a water network to be connected. If the water network or the corresponding storage vessel 50 (see FIG. 3) is not connected, an error message 60 is output on the display 2 .

When the water supply network is properly connected, a corresponding operating pressure builds up in the low pressure range of the water supply network in the high-pressure cleaning device when the spray gun 3 is closed. This can be 3 bar, for example. According to the algorithm of the control unit shown in FIG. 5, this pressure is assessed as sufficient (cf. comparison routine 59 with program branch 61 ). Accordingly, the message "ready" from the microcomputer .mu.R can be entered on the display 2 before the next call of the sensor query routine 58 .

If the spray gun 3 as shown in Fig. 1 or Fig. 3 is operated, the cleaning fluid injected through the high-pressure nozzle into the open. The pressure in the high-pressure cleaning device, namely in the area between pressure outlet 40 and spray gun 3 with pressure hose 4 and connected pressure sensor DS in between, falls below a preset lower threshold value, which corresponds to the normal operating pressure corresponding to the water supply network when the spray gun 3 is closed. The corresponding pressure drop is determined by the control unit via the further comparison routine 62 regarding the lower threshold value after a previous pressure sensor query 58 . If the lower threshold value is not undershot due to the lack of actuation of the spray gun 3 , the pressure sensor query routine 58 is repeated via the program branch 63 and the associated “no” path. If the lower threshold value is undershot, a motor switch-on driver 64 is called up via a subsequent program branch 63 . As a result, the drive motor 7 is switched on via the controlled contactor 53 , and the pump 6 starts. A pressure of 500 bar, for example, is built up over the diameter of the gun nozzle.

The operating pressure between the pressure outlet 40 and the spray gun 3 raised to 500 bar, for example, by the running pump 6 is determined by a further pressure sensor query routine 58 and output on the display 2 by the microcomputer μR. If the actuating lever of the spray gun 3 is released later, i.e. the closing valve in the spray gun 3 is brought into a closed state, the operating pressure between the pump pressure outlet 40 and the spray gun 3 rises above the value of 500 bar stored as the maximum permissible operating pressure. This is determined in the control algorithm according to FIG. 5 via a further comparison routine 65 regarding the upper threshold value after a previous query 58 of the pressure sensor DS. A corresponding motor switch-off driver 67 is then called up in the microcomputer μR via the immediately following program branch 66 . For this, the actuator interface AI is controlled to actuate the contactor 53 to switch off the drive motor 7 and the pump 6 . If the upper threshold value of 500 bar, for example, is not exceeded because the actuating lever of the spray gun 3 is pressed, the program loop 58 , 65 , 66 is repeated. At the end of the driver routine 67 for switching off the engine, the program loop 58 , 62 , 63 is initiated in order to initiate the operating pressure again with the lower pressure threshold value corresponding to the water supply network. When the spray gun 3 is actuated again, the (not shown) gun outlet valve opens, and the operating pressure drops again below the lower threshold value corresponding to the water supply pressure. This is processed via the program loop 58 , 62 , 63 into a command to call the driver routine 64 for switching on the motor in the microcomputer μR. The high-pressure pump 6 is put into operation again by switching on its drive motor 7 .

LIST OF REFERENCE NUMBERS

1

control switchbox

2

display

3

spray gun

4

tube

5

pump head

6

pump unit

7

driving means

8th

receiving body

9

Cavity or working space

10

Plunger body

11

plunger shaft

12

swash plate

13

motor shaft

14

ramp

15

front end

16

strokes

17

bottom dead center

18

Top Dead Center

19

High pressure seal

20

guide bush

21

22

.

22

a O-sealing ring

23

rifle

24

front end

25

annular shoulder

26

extension

27

suction

28

Saugventilfeder

29

torus

30

Saughubfänger

31

suction

32

Saugsammelkanal

33

pressure line

34

Pressure valve ball

35

Pressure valve spring

36

Druckhubfänger

37

.

37

a sealing surfaces

38

Hubfänger guide sleeve

39

plug pipe

40

pressure outlet

41

Pressure collecting channel

42

base ring

43

feather

50

Storage jar

51

T network
DS pressure sensor
C control unit

52

control signals

53

contactor

54

electronics assembly

55

power adapter

56

On / off switch
µR microcomputer
S memory chip
SI sensor interface
AI actuator interface

57

self-test

58

Sample routine

59

"Target range" comparison routine

60

error message

61

program branch

62

"Lower threshold" comparison routine

63

program branch

64

Turn-on drive

65

Upper threshold comparison routine

66

program branch

67

Switch-driver

Claims (18)

1. A method for controlling a high-pressure cleaning device, with a high-pressure pump ( 6 ), which is fed via a suction line ( 31 ) from a liquid supply network or supply ( 50 ), and with a pressure sensor (DS), the operating pressure within of the high-pressure cleaning device and outputs measured values to a controller ( 1 ) which switches the pump ( 6 ) on and off depending on the measured operating pressure, the controller ( 1 ) comparing the operating pressure with a preset lower and a preset upper pressure threshold value , and when the value falls below the lower threshold value, the pump ( 6 ) is switched on and when the upper threshold value is exceeded, the pump ( 6 ) is switched off, characterized in that by means of the pressure sensor (DS) the operating pressure is constantly in the area of a pressure outlet ( 40 ) of the pump ( 6 ) or directly via a pressure channel ( 4 ) starting from this pressure outlet ( 40 ) is detected. 2. The method according to claim 1, characterized in that the lower threshold value in the low-pressure area of the supply network or supply ( 50 ), and the upper threshold value in the high-pressure area of the pressure outlet ( 40 ) of the pump ( 6 ) is placed. 3. The method according to claim 2, characterized in that the lower Threshold value to a pressure range from 0.1 bar to 25 bar, especially 1 up to 10 bar, preferably to 3 bar, and the upper threshold to one Pressure range from 200 bar to 2500 bar, in particular up to 2000 bar, preferably set to 500 bar. 4. The method according to claim 1, 2 or 3, characterized in that the controller ( 1 ) after applying its power supply ( 55 , 56 ) is first subjected to a self-test ( 57 ). 5. The method according to any one of the preceding claims, characterized in that the operating pressure detected for the first time by the controller ( 1 ) is checked to determine whether it corresponds to that of the supply network or supply ( 50 ), and, if appropriate, the controller ( 1 ) sends a corresponding message outputs an input / output interface ( 2 ) to an operator. 6. The method according to any one of the preceding claims, characterized in that the measured operating pressure on an on / off output interface ( 2 ) is displayed to an operator. 7. The method according to any one of the preceding claims, characterized in that the operating pressure is reduced by actuating one or more spray guns ( 3 ) which are connected to the pressure outlet ( 40 ) of the pump ( 6 ) until the lower threshold value is undershot. 8. Computer program with program code elements for a control computer for executing the control method according to one of the preceding claims, when the program is loaded into the programmable control ( 1 ), preferably by means of a microcomputer (µR), and started thereon. 9. Computer program with program code elements according to claim 8, which in a computer memory (S) loaded on a computer readable Data carriers stored or contained in an electrical carrier signal are. 10. Arrangement for controlling the operating pressure in a high-pressure cleaning device, particularly suitable for carrying out the method according to one of the preceding claims, with a motor-driven high-pressure pump ( 6 ), with at least one spray gun ( 3 ), which with the pressure outlet ( 40 ) Pump ( 6 ) is directly connected, and with at least one pressure sensor (DS), the output of which is connected to a preferably electronic control unit ( 1 , 54 , µR) which has an actuator ( 53 ) on the output side for the drive motor ( 7 ) of the pump ( 6 ) controls, characterized in that the pressure sensor (DS) is arranged in an area or section where a pump operating pressure extends directly from the pressure outlet ( 40 ) to the spray gun ( 3 ). 11. The arrangement according to claim 10, characterized in that the pressure sensor (DS) is mounted in or on a pressure collection channel ( 41 ) or other pressure line which extends from the pressure outlet ( 40 ) to the spray gun ( 3 ). 12. The arrangement according to claim 10, characterized in that the pressure sensor (DS) is attached to or within the spray gun ( 3 ). 13. Arrangement according to one of the preceding claims, characterized in that the drive motor ( 7 ) as an electric motor (M), and the actuator ( 53 ) are realized as a contactor. 14. Kit for upgrading a high-pressure cleaning device to form the arrangement according to one of the preceding claims, wherein the high-pressure cleaning device has a direct connection between the pressure outlet ( 40 ) of the high-pressure pump ( 6 ) and the spray gun ( 3 ) and connection means for an electronic control unit ( 1 ) and has a pressure sensor (DS), characterized by the following components:
Pressure sensor (DS), designed for both the low pressure area of the supply network or supply ( 50 ) and the high pressure area of the pressure outlet ( 40 ) of the pump ( 6 ),
Electronics module ( 54 ) as a control unit for coupling to the connection means, and with an interface (SI) to the pressure sensor (DS). 15. Kit according to claim 14, characterized by an actuator ( 53 ) for actuating a drive motor ( 7 ) of the high-pressure pump ( 6 ), the electronics module ( 54 ) having an interface (AI) for actuating the actuator ( 53 ). 16. Kit according to claim 15, characterized in that the actuator ( 53 ) is implemented as a contactor for an electrically designed drive motor (M) of the pump ( 6 ). 17. Kit according to claim 16, characterized in that the contactor ( 53 ) is arranged on the electronics module ( 54 ). 18. Kit according to one of the preceding claims, characterized in that the electronic assembly ( 54 ) comprises a microcomputer (µR) which is provided with program code elements in a memory module (S) for the microcomputer (µR) for executing a control method for the High-pressure cleaning device, in particular according to one of claims 1 to 6, when the program is started in the microcomputer (µR).