DE4323832C2 - Procedure for cleaning vehicle brakes - Google Patents

Description

State of the art

The invention is based on a method for cleaning of vehicle brakes, as well as a cleaning device for Execution of the procedure according to the genus of the claim 1, of claim 3.

For brake and clutch repairs of motor vehicles respirable fine dust and suspended matter arise can lead to serious damage to health. The Cleaning such vehicle brakes or clutches therefore problematic. On the one hand, it must be prevented that the person cleaning the fine dust and Suspended substances, which in some cases still contain asbestos inhales, or that such dusts and substances in the Workshop and third parties. on the other hand must be sufficient, especially hydromechanical Effect to be given to the required To achieve cleaning effect. By the well-known Pressure washers, such as those for the Engine cleaning will be used achieved hydromechanical effect, but it will easily flying brake dusts or suspended matter in the Blown away space, so especially atomized. in this connection are also asbestos-free friction linings Fabrics, especially steel and metal fibers  Heavy metals, as well as carbon black, graphite, phenols and Softeners.

The company Schickert in 7012 Fellbach has one Vehicle brake cleaning device according to the Genus of claim 3 developed, in which the Hot water with temperatures of approx. 95 ° above that cleaning product is sprayed. Crucial here is that this spraying is done under low pressure, namely at a pressure of approx. 6.5 bar. This forms a high temperature low pressure water veil that descends over the product like a shielding bell and binds the loose dust as well as the finest suspended particles. The high ones are decisive for good cleaning Temperatures, decisive for the binding of dust and Particle is the low pressure. By combining high Temperature and low pressure, creates a water mist that descends relatively quickly. The high temperature causes the cleaned part to dry quickly. Around limiting this low pressure works this known cleaning device with a Overpressure protection or a maximum pressure limiter.

In a known cleaning device (DE-OS 35 20 170), with the liquid under high pressure over a Spray gun can be hosed down for cleaning switched a device to a lower pressure to be cleaned with a chemical to apply offset cleaning liquid. It however, this is not a cleaning device for vehicle brakes, for which the Pressure must be limited, but sufficient must be in order to generate the desired hot water mist, but rather a high-pressure device in itself, which is for dispensing certain liquids switchable to lower pressure is.  

DE 32 16 577 A1 describes a high-pressure cleaning device described, in which in the pressure line Pressure gauge is provided. To control the Operating function from the spray gun too relieved by different degrees of closing the same the individual components of the High pressure cleaning device controlled, for example the Burner or the high pressure pump switched on and off or the chemical line is opened and closed.

DE 35 30 954 A1 describes a high-pressure cleaning device known, either with hot water or steam can be operated. To increase security is additionally provided a safety valve as well possibly a steam valve.

Advantages of the invention

The inventive method and the inventive Cleaning device with the characteristic features of the In contrast, claim 1 and claim 3 indicate the Advantage on that to maintain the pressure or Water mist required control is preserved, but beyond that by the continuous flow control of the hot water or a constant of the control devices Water mist can be achieved, especially when over the spray gun of the water mist on or off becomes. Especially at low pressures like the one at inventive method and the inventive Facility are present, changes in the Liquid flow immediately as a change in the Consistency of the water mist, resulting in a Dissolution of the shielding bell and therefore no longer Detection of loose dust or suspended particles.  

The use of flow monitors is true High-pressure cleaning devices known (DE-OS 36 30 362), being when the flow of fluid is interrupted for example after closing the spray gun Pump is turned off. For high pressure cleaning devices the pump generate a correspondingly high pressure what if the water flow is interrupted to a high one Power loss leads because of the high pump Pressure pumped water quantity via a pressure maintaining valve must flow out. In the invention, however, the Flow control a continuity of the amount of water control while doing the additional required Pressure control must prevent overpressure.

With another high pressure cleaning device (DE-PS 41 22 527) a bypass line is provided on the pump with a closing valve, which is at a certain pressure opens and there is also a volume flow sensor in the Pressure line available through which the opening force of the closing valve can be reduced. Although it is here also a control depending on pressures and Flow volume is concerned with the control and the elements used to solve the problems of a Pressure washer with the high pressure given problems of opening and closing Overpressure, which leads to pressure jumps, the one Pose security risk. The invention Problems of a largely constant low pressure very high temperatures are not given here.

So it is basically known that a Overpressure protection in a cleaning device with a the pressure sensor in the pressure line works, which with a switch in the circuit of the Electric motor arranged device interacts with it however, this is not known in the context of a  Low pressure cleaning device with the above Problems. A decisive advantage in the invention especially for a low pressure device for cleaning Vehicle brakes is the combination of Overpressure protection with flow control. Without one such a facility is also the desired one Shielding bell made of water mist only with considerable Guaranteed additional effort.

According to an advantageous embodiment of the invention works the device for liquid flow dependent Control of the cleaning device with one in the circuit of Electric motor arranged flow-dependent switch. According to an advantageous embodiment, the circuit the electric motor a pressure-dependent switch and a flow-dependent switch in parallel connected.  

Further advantages and advantageous configurations of the Invention are the following description, the Drawing and the claims can be removed.

drawing

An embodiment of the inventions is in the Drawing shown and described in more detail below.

Show it:

FIG. 1 is a functional diagram of a cleaning apparatus;

Fig. 2 is an electrical circuit diagram of the cleaning device and

Fig. 3 shows a reprocessing plant for dirty water.

Description of the embodiment

According to the functional diagram shown in FIG. 1 of a cleaning device for cleaning vehicle brakes, which is designed as a low-pressure device, water is drawn in from a water tank 1 via a suction line 2 to a pump 3 and fed via a pressure line 4 to a spray gun 5 which has a spray nozzle 6 and can be controlled via a valve 7 . A minimum water level in the water tank 1 is checked by a low water protection device 8 . The pump 3 is driven by an electric motor 9 , which is controlled by an electrical control unit 11 , the circuit diagram of which is shown in FIG. 2.

If necessary, a cleaning additive, which is present in a container 12, can be added to the water. The container 12 is connected to the suction line 2 via a metering line 13 . A metering valve 14 is arranged in the metering line 13 . A heater 15 is provided in the pressure line 4 for heating the water to approximately 95 ° C. The radiator 15 has heating elements 16 which are switched on or off or regulated by the control device 11 . The maximum temperature is additionally limited by a safety thermostat 17 . The basic temperature is regulated by a thermostat 18 , which is also connected to the electrical control unit 11 .

The water pressure prevailing in the pressure line 4 is measured via a pressure transmitter 19 , which also serves as a pressure relief valve and actuates a switch 21 for the electrical control device 11 . The hot water pressure is made visible downstream of the radiator 15 via a manometer 22 . The working pressure of the water in this cleaning device is set to a low pressure of maximum 7 bar.

In the pressure line 4 there is also a transmitter 23 for measuring the flow of the water, which actuates a flow switch 24 in an electrical line connected to the control unit 11 , which serves to supply power to the pump motor 9 .

With this cleaning device, when the valve 7 of the spray gun 5 is opened and via the nozzle 6, a 95 ° hot low-pressure water mist is generated, which detects the material to be cleaned in a bell-like manner. The low pressure required for this is controlled by the pressure transmitter 19 with switch 21 , while the continuous flow of water can be controlled via the transmitter 23 .

In the circuit diagram shown in FIG. 2, the individual parts are provided with the same reference numbers as in the functional diagram in FIG. 1.

At the point of the three-phase supply for the instantaneous water heater with the heating elements 16 marked with A in the circuit diagram, a 220 volt against 0 volt path is removed. This is inserted into electronics 25 . A transformer converts 220 volts into 15 volts. This voltage is applied to a low level sensor 26 and a floor sensor 27 of the water tank 1 . When the water level is too low, the circuit is closed and the signal is sent to the electronics 25 that there is enough water. This signal activates a relay, which removes the voltage from the low water lamp 28 so that it goes out. It forwards the 220 AC voltage across the marked B point after the point C marked with the electronic 25th There it is placed over the closed pressure switch 21 on the auxiliary relay spool 29 in the point marked D, which ensures that the switch 31 is closed. After turning on the main switch 32 , the current can now flow to the pump motor 9 . This starts up and builds up a pressure greater than 2 bar. The pressure switch 21 opens above 2 bar and the motor stops because switch 30 also opens again. When the pointed gun 5 is opened, a flow arises which actuates a flow switch 24 . If there is a flow, the flow switch 24 and the switch 30 close. As long as the spray gun 5 is open and there is a flow, the current can flow to the pump motor 9 . If the spray gun is closed, the flow stops, flow switch 24 and switch 30 open and the motor stops. The reopening of the spray gun 5 causes a drop in pressure in the system. At 2 bar, the pressure switch 21 and the switch 30 close, so that current can flow to the pump motor 9 again. Pressure and flow builds up to 6.5 bar. If the pressure switch 21 opens above 2 bar, with the spray gun 5 open, the current can flow to the pump motor via the closed flow switch 24 and maintain operation. If there is a lack of water in the electronics 25, the line from B to C is interrupted and the circuit described above comes to a standstill. In contrast, the line from B to E is closed and the low water lamp 28 indicates the low water level. Only after the water tank 1 has been refilled does the lamp go out, the line from B to E is interrupted and the line from B to C closed again, so that the brake washer is ready for operation again.

If the heating is switched on at the main switch 32 , a contactor coil 33 is switched on and off at 95 ° C +/- 4 ° C via the thermostat 18 whose sensor is located in the heated water outlet and thus regulates the temperature in the water heater by switching it on and off each of the 4.5 kW heating elements 16 . If the thermostat 18 is defective, the heater could overheat. A temperature sensor diametrically attached to the thermostat sensor records the temperature and passes it to the safety thermostat 17 . This opens at 110 ° C and locks. It can be switched on again by manual unlocking after the defect has been remedied and heating operation can be restored.

In the reprocessing plant shown in FIG. 3 of the dirty water enriched with dust, heavy metal and floating particles, a truncated pyramid-shaped trough 34 is provided, in which the dirty water is collected. This trough is arranged on a frame 36 provided with rollers 35 , whereby the trough 34 can be pushed directly under the brakes of a jacked-up vehicle. On the one end side of the tub, a filter 37 and a driven by an electric motor 38 circulation pump 39 is mounted on the rack 36 by the sucked dirty water, filtered and purified, and supplied for reuse to the cleaning apparatus of Fig. 1 and Fig. 2 is , The intake manifold 40 of this circulation pump 39 is arranged so far above the bottom of the tub 34 that a sump for the dirt particles can form below the inlet of the intake manifold 40 . The dirt particles floating further up in the water are filtered out via the filter 37 , while the amounts of dirt accumulating in the sump have to be removed from time to time. In order to prevent the circulation pump 39 from running dry, a level sensor working with high-resistance means is arranged in the area of the intake port, by means of which the electric motor 38 is switched off when the water level in the area of the intake port 40 falls below the level required for intake.

The hot water sprayed off during cleaning is fed as dirty water to the reprocessing device, collected there in the tub 34 and, after sludge separation and filtering, fed to the cleaning device for reuse. Both the sludge and the filtered material can be filled into special containers and disposed of as special waste. Usually, the dirty water accumulated when cleaning vehicle brakes is drained and disposed of as far as possible via an oil separator. Here it is unavoidable that in particular heavy metal particles get into the wastewater, which has extremely negative ecological consequences and violates the strict laws regarding the hydrocarbon and pollutant content in wastewater. Moreover, the frequent emptying of the separator is associated with high costs. It is known to collect the cleaning water of a motor vehicle's laundry and to filter it for reuse in a cleaning device (EP-OS 0 363 751), but this is not the dangerous dirt of vehicle brakes, but rather the device is a type Replacement for an oil separator.

The reprocessing plant has the advantage that the coarser and heavier dirt particles are collected in the sump of the container. The finer dirt particles contained in the dirty water are largely removed via a VA filter sieve 37 with swirl protection standing about 10 mm above ground and via a microfilter with 15 micron. A pump 39 ensures that the water is drained from the tub 34 . The largely dry dirt remaining on the bottom of the container can be mechanically removed and disposed of. The filter cartridge saturated after 500-1500 l filtering is also disposed of. The hydrocarbon and heavy metal content of the wastewater is reduced by a factor of 100 in this way. A DEKRA environmental protection comparison analysis shows that the treated water meets the requirements of the Indirect Discharge Ordinance (IndVO) Baden-Württemberg and can be reused as process water. In particular, the cleaned water can be reused for brake cleaning. In such a system, an oil separator can also be dispensed with if necessary, because used oils are scarcely present in the area of a vehicle brake and therefore there are hardly any oils in the dirty water after brake cleaning. Of course, the filtered dirty water can also be drained into the sewage system after the dirty water has been cleaned in accordance with the invention.

The filter has a pre-filter fabric and a Check valve as a backflow preventer. As Filter cartridge designed filter cartridge can then be Contamination can be exchanged because of such fine parts are hardly removable from the filter candle.

The level sensor can be operated with electrical means (high resistance) work. The measuring point is immediately above the Drain connection. This will, above all, also avoided that when the lower filling level is reached Dirt pan with a filling significantly above the Tank sump the pump is turned off to a Avoid running dry. From time to time the can Dirt collected in the container sump can be removed.

Claims (5)

1. Method for cleaning vehicle brakes by hot water provided with cleaning additives and by means of a cleaning device provided with a spray gun
at which the water is heated to approx. 95 ° C,
at which the working pressure is set to a maximum of 7 bar and
where the continuity of the water volume is checked by a flow sensor. 2. The method according to claim 1, characterized in that hosed down for cleaning and cleaning polluted water as dirty water one Reprocessing plant is fed and there after Sludge separation and filtering for the cleaning device Is reused. 3. Cleaning device for performing the method according to claim 1 or 2,
with a water tank ( 1 ) and with a container ( 12 ) for the cleaning additives, which can be added to the water if necessary,
with a pump ( 3 ) which draws in the water and pumps it into a pressure line ( 4 ) and drives it by an electric motor ( 9 ),
with at least one heating element ( 16 ) controlled by a thermostat ( 18 ) in the pressure line ( 4 ),
with a spray gun ( 5 ) which can in particular be operated manually ( 7 ) at the end of the pressure line ( 4 ) and
with a flow-dependent switch ( 24 ) provided in the circuit of the electric motor and detecting the water flow in the pressure line. 4. Cleaning device according to claim 3, characterized in that for controlling the device a pressure in the pressure line detecting sensor ( 19 ) is provided which actuates a switch ( 21 ) in the circuit of the electric motor, the switch opening above about 2 bar and is connected in parallel with the flow-dependent switch ( 24 ). 5. Cleaning device according to claim 3 or 4, characterized characterized that a water supply control is available is.