High-pressure cleaning machine

Abstract

Described is a high-pressure washer (100) comprising:-a pump (40) and an electric motor (50) configured to actuate the pump (40), where the pump (40) is connected to an inlet conduit (15) for liquid to be pressurized and to a delivery conduit (20) for liquid pressurized by the pump (40); -a dispensing gun (25) for fluidly connecting the pressurized liquid to the delivery conduit (20), the dispensing gun (25) being actuatable by pressing a trigger (35), the trigger (35) being movable between a first position in which the dispensing gun (25) does not dispense any pressurized liquid and a second position in which the dispensing gun (25) dispenses pressurized liquid; -a signal generator which can be activated by pressing the trigger (35); -an electronic control unit (60) operatively connected to the electric motor (50) and to the signal generator; wherein the electronic control unit (60) is configured to receive, from the signal generator, a signal representative of a change in pressure on the delivery conduit (20) due to actuation of the trigger (35) of the dispensing gun (25), and to activate an additional function (FA) of the high-pressure washer (100) if the electronic control unit detects a predetermined number of signals within a predetermined time interval.

Description

Technical Field

[0001] The present invention relates to high pressure cleaners, ie high pressure cleaning devices for cleaning surfaces by generating pressurized jets of liquid. Background Art

[0002] As is known, a high-pressure cleaning device or pressure washer comprises a high-pressure pump adapted to pump a cleaning fluid, such as water, the delivery conduit of which is connected to a flexible hose connected to a dispensing gun of the pressurized liquid.

[0003] A dispensing spray gun generally comprises an elongated body provided with a handle, to which a dispensing lance for supporting a dispensing nozzle is removably connected at its free end.

[0004] The dispensing spray gun then comprises a trigger which is arranged at the handle and which actuates a spray head suitable for allowing or interrupting the flow of cleaning fluid from the pump to the dispensing nozzle.

[0005] The fluid delivered to the spray gun is pressurized by an electric pump, which is a pump in which at least one electric motor is mechanically connected to the pump for the purpose of supplying mechanical energy to the pump to pressurize the liquid.

[0006] High-pressure cleaning machines of known type comprise manual selection means, for example fixed to a housing containing the pump, adapted to allow actuation of the pump in various modes of use.

[0007] Indeed, one can envision using the eco-mode, which saves water and energy, for cleaning surfaces that are not particularly dirty and / or delicate, or the high-pressure washer mode, for cleaning surfaces such as stone, concrete and brick, surfaces such as metal railings and gates, or for cleaning objects such as work and garden tools and vehicles or others.

[0008] Switching the high-pressure cleaner on and off and changing between different working programs is only possible by using a manual selection device fixed to the housing that accommodates the pump.

[0009] However, it is not always easy or convenient to actuate a switch or manual selector that is placed in position to command various functions of the high pressure washer in all situations where the machine is used.

[0010] The object of the invention is to increase the versatility and ease of use of such a high-pressure cleaning machine within the scope of a simplified, rational and robust construction solution.

[0011] These objects are achieved by the features of the invention set out in the independent claim. The dependent claims outline preferred and / or particularly advantageous aspects of the invention. Summary of the invention

[0012] Specifically, the present invention provides a high-pressure cleaning machine, comprising:

[0013] - a pump and an electric motor configured to actuate the pump, wherein the pump is connected to an inlet duct for the liquid to be pressurized and to a delivery duct for the liquid pressurized by the pump;

[0014] a dispensing gun for fluidly connecting a pressurized liquid to a delivery conduit, the dispensing gun being actuatable by pressing a trigger, the trigger being movable between a first position, in which the dispensing gun does not dispense any pressurized liquid, and a second position, in which the dispensing gun dispenses the pressurized liquid;

[0015] - a signal generator which can be activated by pressing the trigger;

[0016] - an electronic control unit operatively connected to the electric motor and the signal generator;

[0017] Therein, the electronic control unit is configured to receive from the signal generator a signal representing a pressure change on the delivery pipe caused by an actuation of the trigger of the dispensing gun, and to activate an additional function of the high-pressure cleaner if the electronic control unit detects a predetermined number of signals within a predetermined time interval.

[0018] Thanks to this solution, a high-pressure cleaning machine is created which allows the user to intervene in the operation of the high-pressure cleaning machine in a comfortable and intuitive manner, without having to actuate a switch on the machine housing.

[0019] According to an embodiment of the present invention, the signal generator includes a first pressure switch configured to detect a pressure change on the delivery conduit caused by actuation of a trigger of the dispensing gun and to act on the electrical switch according to the pressure change.

[0020] An advantage of this embodiment is that it allows the use of commonly used components to perform functions that intervene in the operation of the high pressure washer.

[0021] One aspect of the present invention provides that an electrical switch of a first pressure switch can be actuated from a first disconnected position to a second position, wherein in the first disconnected position the electrical switch is grounded and in the second position the electrical switch is connected to an electronic control unit to send an electrical signal thereto, the signal being indicative of a trigger depression event of the dispensing gun.

[0022] An advantage of such an embodiment is that the first pressure switch is operable as a transducer to convert a pressure event of the trigger of the dispensing gun into an electrical signal to be sent to the electronic control unit, the electrical signal being representative of the trigger press event.

[0023] According to one embodiment of the invention, the first pressure switch comprises a rod movable against the force of a spring and adapted to actuate the electrical switch from a first position to a second position when a trigger pressing event results in a pressure drop in the delivery conduit.

[0024] According to another embodiment of the present invention, the electronic control unit is configured to start a predetermined time interval at the moment when the first trigger pressing event occurs and start counting the trigger pressing events.

[0025] An advantage of this embodiment is that the counting of trigger press events occurs automatically and immediately with the first trigger press event.

[0026] According to another embodiment of the present invention, the high-pressure cleaning machine provides a second pressure switch arranged on the delivery pipe, wherein the second pressure switch is configured to act on an electric switch, wherein in a first normally closed position the electric switch is connected to a power supply circuit of a motor of the pump, and in a second position the switch is connected to ground.

[0027] An advantage of such an embodiment is that opening of the electrical switch of the second pressure switch causes the pump to stop, thereby providing a full stop safety function.

[0028] According to one embodiment of the invention, the second pressure switch comprises a rod movable against the force of a spring and adapted to actuate the electric switch from the first position to the second position when the delivery pressure of the pump is above a predetermined calibration value. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Further characteristics and advantages of the invention will become more apparent upon reading the following description, provided by way of non-limiting example, with the aid of the accompanying drawings.

[0030] Figure 1 is a schematic diagram of a high pressure cleaning machine according to the present invention.

[0031] Figure 2 It shows Figure 1 A schematic diagram of a first operating mode of the high pressure cleaning machine, and

[0032] Figure 3 It shows Figure 1 Schematic diagram of a second operating mode of the high pressure washer. DETAILED DESCRIPTION

[0033] Specific reference Figure 1 , reference numeral 100 generally indicates a high pressure cleaning machine or a high pressure cleaning device.

[0034] The high pressure washer 100 comprises a box-like housing 10 , for example made of plastic material, to which preferably a handle and / or wheels (not shown) are associated for moving the high pressure washer itself.

[0035] The high-pressure cleaning machine 100 comprises a single inlet pipe 15 for the liquid to be pressurized, such as a single inlet conduit 15 for the liquid to be pressurized, which is suitable for connection to a source of liquid to be pressurized, such as a tank or a water network.

[0036] The inlet duct is at least partially housed within the housing 10 .

[0037] The high pressure washer 100 further comprises a delivery conduit 20 for pressurized liquid, for example a single delivery conduit 20 for pressurized liquid, and a dispensing gun 25, wherein the delivery conduit 20 is fluidly connected to the dispensing gun 25, for example by a flexible hose. The delivery conduit 20 is at least partially accommodated in the housing 10, for example.

[0038] The dispensing gun 25 comprises a body equipped with a handle 37 to which is associated in a removable manner, for example, a dispensing rod 30 equipped with a dispensing nozzle 32 at one of its free ends.

[0039] As an alternative to a wand, any other cleaning tool, such as a rotating brush, may also be associated with the dispensing gun 25 .

[0040] The dispensing gun 25 may include a trigger 35 that is movable between a first position, in which the dispensing gun does not dispense pressurized liquid, and a second position, in which the dispensing gun dispenses pressurized liquid.

[0041] In particular, the trigger 35 is disposed at the handle 37 of the dispensing gun 25 and actuates the valve between a first position in which the valve allows pressurized liquid to flow from the delivery conduit 20 to the dispensing nozzle and a second position in which the valve interrupts the flow of pressurized liquid from the delivery conduit 20 to the dispensing nozzle 32.

[0042] The high-pressure cleaning machine further comprises a pump 40 connected at an inlet to the inlet pipe 15 and at an outlet to the delivery pipe 20 , preferably the pump 40 having a fixed displacement.

[0043] The high pressure washer 100 also includes a motor 50 configured to actuate the pump 40. That is, the second motor 50 is mechanically connected to the second pump 40 to actuate the pump 40, thereby pressurizing the fluid from the inlet pipe 15. Overall, the motor 50 and the pump 40 form an electric pump of the high pressure washer 100.

[0044] The electric motor 50 is adapted to be electrically connected to an electrical energy source, ie to an electrical distribution network and / or to a battery, for example housed within the housing 10 .

[0045] The high pressure washer 100 further comprises an electronic control unit 60 which is operatively connected to the motor 50 , for example by an electrical connection.

[0046] The high pressure washer 100 further includes a signal generator, which is operably connected to the electronic control unit 60 and can be activated by pressing the trigger of the dispensing gun 25. According to the present embodiment, the signal generator includes a first pressure switch 70 disposed on the delivery pipe 20, wherein the pressure switch 70 has a rod 72 that can move against the force of a spring 74, so that the rod 72 can selectively act on an electric switch 75. In other embodiments of the present invention, the signal generator can be implemented with different known components.

[0047] Preferably, the electrical switch 75 is in the form of a normally open switch (NA), wherein in an open position the electrical switch 75 is connected to ground, and in a second (closed) position the electrical switch is connected to the electronic control unit 60 to send an electrical signal thereto.

[0048] Furthermore, the high-pressure cleaning machine 100 comprises a second pressure switch 80 which is also arranged on the delivery line 20 , wherein the second pressure switch 80 has a rod 82 which is movable against the force of a spring 84 so as to be able to selectively act on an electric switch 85 .

[0049] Preferably, the electrical switch 85 of the second pressure switch 80 is in the form of a normally closed switch (NC), wherein in the closed position the electrical switch is connected to the power supply circuit of the motor 50 of the pump 40, and in the second (open) position the switch is connected to ground.

[0050] Specifically, when the delivery pressure of the pump 40 is lower than a predetermined calibration value P th When the pressure exceeds the calibration value P th When the electric switch 85 is automatically disconnected.

[0051] Opening of the electrical switch 85 of the second pressure switch 80 causes the pump 40 to stop, thereby providing a complete stop function, and occurs, for example, when the dispensing gun 25 is closed, thereby increasing the pressure upstream thereof.

[0052] Obviously, the calibration pressure value of the first pressure switch 70 must be lower than or almost equal to the predetermined calibration pressure P of the second pressure switch 80. th value.

[0053] Figure 1 Also shown is a power line 110 which comprises two cables, one L being the power line and the other N being the neutral phase.

[0054] The cables L and N are connected to a manually operated double pole switch 90 from which the power supply cable for the electric motor 50 driving the pump 40 is derived.

[0055] The operation of the high pressure cleaning machine 100 according to the present invention is as follows.

[0056] In the standby state, the double pole switch 90 is open and the dispensing gun 25 does not dispense any fluid.

[0057] In this configuration, the motor 50 is not operational and the pump 40 is not operational.

[0058] Since the dispensing pressure of the pump 40 is equal to zero, the switch 85 of the second pressure switch 80 is in the closed position (NC).

[0059] When the operator desires to initiate high pressure washer operation, the operator actuates the double pole switch 90 to energize the motor 50 .

[0060] In this position, the pump 40 is activated and the delivery pressure reaches a value higher than the calibrated value P th The value of .

[0061] Since the pressure exceeds the calibration value P th , the rod 82 of the second pressure switch 80 is Figure 1 The second pressure switch 80 moves in the direction of arrow G against the spring 84 , the normally closed (NC) switch 85 is opened, and the motor 50 stops.

[0062] When the operator wishes to dispense pressurized water, the operator opens the dispensing gun 25 via the trigger 35 and the pressure of the water (or fluid) upstream of the gun 25 is reduced.

[0063] This causes the rod 82 of the switch 85 of the second pressure switch 80 to be moved along with the Figure 1 Pushing in the direction opposite to the direction of arrow G returns the switch 85 to the normally closed (NC) position and the motor 50 starts.

[0064] When the operator wishes to interrupt the dispensing of pressurized water, the operator simply releases the trigger 35 by closing the dispensing gun 25, causing the pressure upstream of the gun to increase to above the calibrated value P th , and the normally closed switch (NC) 85 of the second pressure switch 80 is opened as in the above-mentioned mode, and the motor 50 stops.

[0065] In addition, according to the embodiments of the present invention, the pressure change occurring in the transport pipeline can be utilized. Figure 2 and Figure 3 As shown, the additional function FA of the high pressure washer 100 is commanded using the first pressure switch 70 and the trigger 35 of the dispensing gun 25 according to the following mode.

[0066] In these operating modes, Figure 2 In the example case, the reference time interval Δt is predetermined and equal to 2 seconds, ie, 20 tenths of a second.

[0067] Furthermore, the intervention condition of the additional function FA of the high-pressure washer 100 is pre-established as a function of the number of times the trigger 35 is pressed within a reference time interval Δt, for example, in the case of three trigger presses within a reference time interval Δt, the intervention of the additional function FA of the high-pressure washer 100 can be activated, and in the mode shown below such trigger press events are detected by the electronic control unit 60. In practice, with each actuation of the trigger, the pressure of the delivery duct sensed by the pressure switch 70 changes, which pressure causes the switch 75 to switch. In practice, the pressure switch 70 and the switch 75 activate the signal generator according to the change in the pressure of the delivery duct 20, as better explained below.

[0068] In other words, if the electronic control unit 60 detects a predetermined number of said signals within a predetermined time interval, that is, if the electronic control unit 60 counts a predetermined number of signals indicating a pressure change on the delivery pipe 20 (signals generated due to actuation of the trigger 35 of the dispensing gun within a predetermined time interval), the electronic control unit 60 is configured to receive a signal indicating a pressure change on the delivery pipe 20 from the signal generator and activate an additional function of the high-pressure cleaning machine.

[0069] As described above, upon activation of the movable trigger 35 of the dispensing gun 25 , the fluid pressurized by the pump is dispensed by the gun 25 through the dispensing wand 30 and the dispensing nozzle 32 , while a pressure drop occurs in the delivery conduit 20 .

[0070] In this case, the first pressure switch 70 also experiences such a pressure drop.

[0071] More specifically, the rod 72 of the first pressure switch 70 moves along the Figure 1 moves in the direction of arrow F and acts on the electrical switch 75, thereby moving it from a first normally open position (NA) connected to ground to a second position connected to the electronic control unit 60 to send an electrical signal to the electronic control unit 60.

[0072] Therefore, at the moment when the pressure of the trigger 35 is generated, the first signal S1 is sent from the electronic control unit 60, and at the same time, the timer is started from the moment t0 corresponding to the event S1, and the reference time interval Δt and the counter count the first event C1 representing the first pressure of the trigger 35. That is, at the moment t0 when the first event occurs, representing the first pressure of the trigger 35 and indicated by the first signal S1, the reference time interval Δt starts and the counter counts the first event, that is, the event C1.

[0073] If Figure 2As shown, at least two other trigger pressing events S2 and S3 occur within the reference time interval Δt, i.e., two trigger pressing events indicated by respective signals S2 and S3, which cause respective increments C2 and C3 of counters, which count the second and third trigger 35 pressing events (in the example provided, the latter occurring still within the reference time interval Δt). Figure 2 The time t x ).

[0074] In this case, the electronic control unit 60 activates additional functions FA of the high-pressure cleaning machine 100, such as a function for increasing or decreasing the pressure of the output jet, or a function for varying the flow rate of the output jet, or other functions implementable in a high-pressure washer.

[0075] On the other hand, if Figure 3 As shown, if at least two other trigger 35 pressing events do not occur within the reference time interval Δt, the additional function of the high pressure cleaning machine 100 is not activated.

[0076] When the reference time interval Δt has elapsed, the timer returns to zero in any case, as does the counter.

[0077] At the moment a new trigger 35 press event occurs, the timer is restarted for the entire duration of the new time interval (always equal to Δt) to check again how many trigger 35 press events have occurred during the new time interval Δt.

[0078] Preferably, the two pressure switches 70, 80 are different and separate. The first pressure switch 80 is used only to open / close the flow of detergent to the spray gun to dispense or not dispense the same detergent to the outside. The second pressure switch 70 is used only to activate an additional function based on the presence of at least two signals indicating a pressure change on the delivery pipe 20, which is caused by actuating the trigger 35 of the dispensing gun within a predetermined time period Δt.

[0079] The invention thus conceived is susceptible of several modifications and variations, all of which are within the scope of the inventive concept.

[0080] Moreover, all the details may be replaced by other technically equivalent elements.

[0081] In practice, the materials used, as well as the accidental shapes and dimensions, may vary according to requirements without thereby departing from the scope of protection of the appended claims.

Claims

1. A high pressure cleaning machine (100), comprising: a pump (40) and an electric motor (50) configured to actuate the pump (40), wherein the pump (40) is connected to an inlet conduit (15) for the liquid to be pressurized and to a delivery conduit (20) for the liquid pressurized by the pump (40); a dispensing gun (25) for fluidly connecting the pressurized liquid to the delivery duct (20), the dispensing gun (25) being actuatable by pressing a trigger (35), the trigger (35) being movable between a first position, in which the dispensing gun (25) does not dispense any pressurized liquid, and a second position, in which the dispensing gun (25) dispenses the pressurized liquid; - a signal generator which can be activated by pressing the trigger (35); - an electronic control unit (60) operatively connected to the electric motor (50) and to said signal generator; The electronic control unit (60) is configured to receive from the signal generator a signal representing a change in pressure on the delivery pipe (20) caused by actuation of the trigger (35) of the dispensing gun (25), and to activate an additional function (FA) of the high-pressure cleaning machine (100) if the electronic control unit detects a predetermined number of said signals within a predetermined time interval (Δt).

2. The high pressure cleaning machine (100) according to claim 1, wherein: The signal generator includes a first pressure switch (70) configured to detect a pressure change on the delivery conduit (20) caused by actuation of the trigger (35) of the dispensing gun (25) and to act on an electrical switch (75) based on the pressure change.

3. The high pressure cleaning machine (100) according to claim 2, wherein: The electrical switch (75) of the first pressure switch (70) is actuatable from a first disconnected position, wherein the electrical switch (75) is connected to ground, to a second position, wherein the electrical switch (75) is connected to the electronic control unit (60) to send an electrical signal to the electronic control unit (60), the signal being indicative of a trigger (35) depression event of the dispensing gun (25).

4. The high pressure cleaning machine (100) according to claim 3, wherein: The first pressure switch (70) includes a rod (72) which is movable against the force of a spring (74) and is adapted to actuate the electrical switch (75) from the first position to the second position when a trigger (35) pressing event causes a pressure drop in the delivery conduit (20).

5. The high pressure cleaning machine (100) according to claim 2, wherein: The high-pressure cleaning machine (100) provides a second pressure switch (80) arranged on the delivery pipe (20), wherein the second pressure switch (80) is configured to act on an electric switch (85), wherein the electric switch (85) is connected to a power supply circuit of the motor (50) of the pump (40) in a first normally closed position, and the switch (85) is grounded in a second position.

6. The high pressure cleaning machine (100) according to claim 5, wherein: The second pressure switch (80) includes a rod (82) that is movable against the force of a spring (84) and is configured to switch on when the delivery pressure of the pump (40) is above a predetermined calibration value (P th ) actuates the electrical switch (85) from the first position to the second position.

7. The high pressure cleaning machine (100) according to claim 1, wherein: The electronic control unit (60) is configured to start the predetermined time interval (Δt) at the moment when the first trigger (35) pressing event occurs and start counting the trigger (35) pressing events.

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