SPRAY GUN FOR A HIGH-PRESSURE CLEANING APPLIANCE

Abstract

A spray gun for a high-pressure cleaning appliance is provided, with a gun casing, in which is arranged a valve, which has a through duct which extends from a valve inlet to a valve outlet, and has a closure body which, in a closed position, bears in a fluid-tight manner against a valve seat and which is adapted to be moved, with the aid of a hand lever mechanically coupled to the closure body, into an open position spaced apart from the valve seat, and with an electric apparatus which has an electric display device and at least one battery. The electric apparatus has an electric casing which is sealed against sprayed water and forms a sub-unit adapted to be handled independently, wherein all of the current-carrying components of the spray gun are arranged in the electric casing and are separated galvanically from the remaining components of the spray gun.

Claims

1. A spray gun for a high-pressure cleaning appliance, with a gun casing, in which there is arranged a valve, wherein the valve has a through duct which extends from a valve inlet to a valve outlet, and wherein the valve has a closure body which, in a closed position, bears in a fluid-tight manner against a valve seat and which is adapted to be moved, with the aid of a hand lever mechanically coupled to the closure body, into an open position spaced apart from the valve seat, and with an electric apparatus which has an electric display device and at least one battery, wherein the electric apparatus has an electric casing which is sealed against sprayed water and forms a sub-unit which is adapated be handled independently, wherein all of the current-carrying components of the spray gun are arranged in the electric casing and are separated galvanically from the remaining components of the spray gun.

2. The spray gun according to claim 1, wherein the electric casing is releasably mechanically connectable to the gun casing.

3. The spray gun according to claim 1, wherein the electric apparatus has a standby mode and a usable operating mode, wherein the energy consumption of the electric apparatus in the standby mode is lower than in the usable operating mode, and wherein the usable operating mode is activatable by the user and when the spray gun is not in use the electric apparatus changes automatically into the standby mode at the latest after a predetermined period of time has elapsed.

4. The spray gun according to claim 3, wherein the spray gun has at least one activation member movable by the user for activating the usable operating mode.

5. The spray gun according to claim 4, wherein at least one activation member is arranged outside the electric casing in the gun casing and is movable back and forth between a rest position and an activation position, wherein the usable operating mode is wirelessly activatable by moving the activation member (62) from the rest position into the activation position.

6. The spray gun according to claim 5, wherein the activation member arranged outside the electric casing is wirelessly coupled in its activation position to a switching or sensor element of the electric apparatus and the coupling is interrupted in the rest position of the activation member.

7. The spray gun according to claim 4, wherein the usable operating mode is only active when the at least one activation member is in its activation position.

8. The spray gun according to claim 4, wherein, after a change of the activation member from the activation position into the rest position, the usable operating mode is still active until a predetermined time period has elapsed.

9. The spray gun according to claim 4, wherein the activation member arranged outside the electric casing is coupled to the hand lever.

10. The spray gun according to claim 9, wherein the activation member arranged outside the electric casing is rigidly connected to the hand lever.

11. The spray gun according to claim 4, wherein the activation member arranged outside the electric casing is coupled in the activation position magnetically, inductively, capacitively, optically, piezo-electrically or electromagnetically to a switching or sensor element of the electric apparatus.

12. The spray gun according to claim 11, wherein the activation member arranged outside the electric casing is a permanent magnet and in that the switching element is magnetic field-sensitive.

13. The spray gun according to claim 12, wherein the switching element is configured as a reed switch.

14. The spray gun according to claim 4, wherein at least one activation member is configured as a manually actuatable input element of the electric apparatus.

15. The spray gun according to claim 14, wherein the electric apparatus has at least two manually actuatable input elements which each form an activation member.

16. The spray gun according to claim 3, wherein the standby mode is a rest state in which the electric apparatus does not consume energy.

17. The spray gun according to claim 3, wherein in the standby mode, the transmission of electric energy from the battery to all current consumers of the electric apparatus is interrupted.

18. The spray gun according to claim 1, wherein the spray gun has a pressure detecting device for detecting the fluid pressure prevailing downstream of the valve seat in the through duct, wherein the pressure detecting device is arranged outside the electric casing in the gun casing and is wirelessly coupled to a sensor element of the electric apparatus arranged in the electric casing.

19. The spray gun according to claim 18, wherein the pressure detecting device is magnetically, inductively, capacitively, optically, piezo-electrically or electromagnetically coupled to the sensor element.

20. The spray gun according to claim 18, wherein the sensor element is magnetic field-sensitive and wherein the pressure detecting device has a permanent magnet whose spacing from the sensor element is variable in dependence on the fluid pressure prevailing downstream of the valve seat in the through duct.

21. The spray gun according to claim 20, wherein the permanent magnet is rigidly connected to a push part, which is displaceable against an elastic restoring force in dependence on the fluid pressure in a guide part prevailing downstream of the valve seat in the through duct.

22. The spray gun according to claim 21, wherein the push part is rigidly connected to a measuring member, which is adapted to be acted upon by the fluid pressure prevailing downstream of the valve seat in the through duct.

23. The spray gun according to claim 1, wherein one of a plurality of pressure ranges can be visually displayed on the display device in dependence on the pressure prevailing downstream of the valve seat in the through duct.

24. The spray gun according to claim 1, wherein at least one recommendation, dependent on the pressure of the fluid, for a spray nozzle can be displayed on the display device.

25. The spray gun according to claim 1, wherein the display device has a plurality of visual display elements.

26. The spray gun according to claim 1, wherein the display device has a liquid crystal display.

27. The spray gun according to claim 1, wherein the electric apparatus has a transmitting device for wireless transmission of signals from the electric apparatus to the high-pressure cleaning appliance.

28. The spray gun according to claim 1, wherein the electric apparatus has a receiving device for wireless transmission of signals from the high-pressure cleaning appliance to the electric apparatus.

29. The spray gun according to claim 1, wherein the electric apparatus has a transceiver.

30. The spray gun according to claim 1, wherein on the display device a plurality of cleaning parameter ranges can be visually displayed and a desired cleaning parameter range can be selected by the user, wherein the desired cleaning parameter range can be wirelessly transmitted from the electric apparatus to the high-pressure cleaning appliance.

31. The spray gun according to claim 1, wherein the electric apparatus has at least one input element for inputting and/or selecting a control command.

32. The spray gun according to claim 31, wherein the electric apparatus has a rigid printed circuit board, on which the at least one input element and the electric display device are arranged, wherein the at least one input element is coupled to an operating element which has a user-operable interface, wherein the user interface is inclined to a plane which is defined by the display device.

33. The spray gun according to claim 32, wherein the at least one input element is configured as an input key which is adapted to be acted upon with an actuation force by an associated operating element.

34. The spray gun according to claim 32, wherein the at least one operating element is configured as a force diverting element which is movably mounted on the electric casing.

35. The spray gun according to claim 34, wherein the force diverting element is configured as a tumbler.

36. The spray gun according to claim 32, wherein the spray gun has a handle which is adapted to be gripped by the user, and wherein the at least one user interface is arranged at an end of the handle facing the display device.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0057] FIG. 1 shows a schematic longitudinal sectional view of a first advantageous embodiment of a spray gun according to the invention;

[0058] FIG. 2 shows an enlarged partial sectional view of the spray gun of FIG. 1;

[0059] FIG. 3 shows a perspective view of a pressure detecting member of the spray gun of FIG. 1;

[0060] FIG. 4 shows a schematic block diagram of an electric apparatus of the spray gun of FIG. 1;

[0061] FIG. 5 shows an enlarged partial sectional view of a second advantageous embodiment of a spray gun according to the invention;

[0062] FIG. 6 shows a perspective view of an electric apparatus of the spray gun of FIG. 5 with the electric casing open;

[0063] FIG. 7 shows a simplified block diagram of the electric apparatus of FIG. 6.

DETAILED DESCRIPTION OF THE INVENTION

[0064] In FIGS. 1 to 4, a first advantageous embodiment of a spray gun according to the invention is schematically shown, which is designated overall by the reference symbol 10. The spray gun 10 comprises a gun casing 12 which is formed from a first casing half-shell 14 and a second casing half-shell, not shown in the drawing, and which has a central casing region 16 which is arranged between a front casing region 18 and a rear casing region 20. The front casing region 18 accommodates an outlet conduit 22 which is connected at its free end facing away from the central casing region 16 to a connecting device 24. With the aid of the connecting device 24 there can be connected to the outlet conduit 22 a spray nozzle or a spray lance.

[0065] The central casing region 16 accommodates a valve 26 with a valve casing 28 which has a valve inlet 30 and a valve outlet 32 and a through duct 34 which extends from the valve inlet 30 to the valve outlet 32 and in which a closure body 36 is displaceably held. To the valve outlet 32, the outlet conduit 22 is connected and to the valve inlet 30, a pressure hose can be connected in a manner known per se to a person skilled in the art, which is in flow connection with the pressure outlet of a high-pressure cleaning appliance. Via the pressure hose, the spray gun 10 can be provided with fluid, preferably water, which is put under pressure by the high-pressure cleaning appliance, and via the outlet conduit 22 the fluid can be discharged.

[0066] The rear casing region 20 forms a handle 38 which projects from the central casing region 16 and a guard bow 42 extends from the free end region 40 of the handle to the central casing region 16. The guard bow 42, the central casing region 16 and the handle 34 surround a handle aperture 44, into which the user can reach with his fingers when gripping the handle 38.

[0067] The valve casing 28 forms an arm 46 on which a hand lever 48 is pivotably mounted about a pivot axis 50. The hand lever 48 extends, at the front side of the handle 38 facing the guard bow 42, along as far as the free end region 40 of the handle 38. It can be pivoted by the user about the pivot axis 50 by the user gripping the handle 38 together with the hand lever 42 with his fingers.

[0068] At its end facing away from the handle aperture 44, the hand lever 48 carries an actuating element 52 which bears against a valve tappet 54. The valve tappet 54 is integrally connected to the closure body 36 of the valve 26. By pivoting of the hand lever 48 about the pivot axis 50, the valve tappet 54 can be moved back and forth together with the closure body 36 in the through duct 34 between a closed position shown in the drawing and an open position not shown in the drawing. In the closed position the closure body 36 bears in a fluid-tight manner against a valve seat 56, so that the flow connection between the valve inlet 30 and the valve outlet 32 is interrupted, and in an open position the closure body 36 is spaced from the valve seat 56 and thereby frees the flow connection between the valve inlet 30 and the valve outlet 32.

[0069] The valve tappet 54 is surrounded in the region between the actuating element 52 and an outer side of the valve casing 28 by a first restoring spring 58, which acts upon the hand lever 48 with a spring-elastic restoring force when the valve tappet 54 together with the closure body 36 is moved from its closed position to its open position by pivoting of the hand lever 48.

[0070] At the level of the pivot axis 50 the hand lever 48 is integrally connected to a pivot arm 60 which can be pivoted together with the hand lever 48 about the pivot axis 50 and carries at its free end an activation member in the form of a first permanent magnet 62. The importance of the first permanent magnet 62 will be explained in more detail below.

[0071] At the rear side 64, facing away from the closure body 36, of the arm 46 an accommodating sleeve 66 is formed, into which a guide cylinder 68 dips with an extension 70. By means of clamping pins 72, 74 the extension 70 is releasably held in the accommodating sleeve 66.

[0072] The guide cylinder 68 is configured hollow and is closed at its rear side facing away from the extension 70 by means of a plug 76. At two diametrically opposite longitudinal sides, the guide cylinder 68 has in each case a longitudinal slot, although only one of the longitudinal slots can be seen in the drawing and is designated by the reference symbol 78.

[0073] The guide cylinder 68 accommodates a piston-like push part 80 which is rigidly connected, via a holding arm 82 passing through the longitudinal slot 78 from the inside to the outside, to a holder 84 for a second permanent magnet 86. The second permanent magnet 86 is latched into the holder 84, the holder 84 having for this purpose two opposite, elastically deformable latching elements 88, 90.

[0074] The push part 80 is acted upon by a second restoring spring 92 with a spring-elastic restoring force. The second restoring spring 92 is arranged in the guide cylinder 68 on the side of the push part 80 facing away from the extension 70 and is supported at one end on the push part 80 and at the other end on the plug 76.

[0075] The push part 80 is rigidly connected to a measuring member in the form of a measuring rod 94 which passes through the extension 70 and dips into a measuring duct 96. The measuring duct 96 opens downstream of the valve seat 56 into the through duct 34, so that the front side of the measuring rod 94 facing the through duct 34 is acted upon by the pressure of the fluid prevailing downstream of the valve seat 56 and, together with the push part 80 and the second permanent magnet 86 fixed thereto via the holding arm 82, can be displaced against the spring-elastic restoring force of the second restoring spring 92.

[0076] Within the measuring duct 96 the measuring rod 94 is surrounded in the circumferential direction by a sealing element, preferably a sealing ring, not shown in the drawing to achieve a better overview, which ensures that fluid cannot escape from the valve casing 28 via the measuring duct 96.

[0077] The gun casing 12 forms in the central casing region 16, on the top side facing away from the valve inlet 30, a casing receptacle 98 which accommodates an electric apparatus 100. The electric apparatus 100 has an electric casing 102 which is sealed against sprayed water and is releasably connectable to the gun casing 12. The electric casing 102 for this purpose has a front connecting strap 104 and a rear connecting strap 106, which can be inserted between the casing half-shells of the gun casing 12 and through which can be passed connecting screws which are used for screwing on the two casing half-shells of the gun casing 12.

[0078] The electric casing 102 has a casing lower part 108 and a casing upper part 110 which are fluid-tightly connected to each other. The electric casing 102 forms a battery compartment 112, into which at least one rechargeable battery 114 can be inserted. The battery compartment 112 is arranged in a front casing half 116 of the electric casing 112. In addition, the electric casing 102 has an accommodating area 118 which is arranged in a rear casing half 120 of the electric casing 102. The front casing half 116 faces the front casing region 18 of the gun casing 12, and the rear casing half 120 of the electric casing 102 faces the handle 38 of the gun casing 12.

[0079] In order to allow access to the battery compartment 112, the casing upper part 110 in the front casing half 116 has a casing aperture 122 which can be fluid-tightly closed by a battery compartment cover 124. The battery compartment cover 124 bears fluid-tightly against the casing lower part 108 with the interposition of a sealing ring 126 and can be screwed by means of connecting screws 128 to the casing lower part 108.

[0080] In the region of the rear casing half 120, the casing upper part 110 of the electric casing 102 is of transparent design and forms a viewing window 130 sealed against sprayed water.

[0081] The accommodating region 118 accommodates a rigid printed circuit board 132, on which a multiplicity of current-carrying electric components are held, which are electrically connected via flexible conductor tracks 134 to the battery 114. The current-carrying electric components comprise a microcontroller 136 which is electrically connected to a magnetic field-sensitive sensor, in the illustrated exemplary embodiment to a Hall sensor 138, and to a display device 140. Electric energy can be provided to the microcontroller 136 and the Hall sensor 138 via a voltage transformer 142 and a switching transistor 144 by the battery 114. A control input 146 of the switching transistor 144 is connected via a first ohmic resistor 148 and a reed switch 150 to earth potential, and a second ohmic resistor 152 is connected in parallel with the base-emitter path of the switching transistor 144, via which the control input 146 of the switching transistor 144 is connected to the battery 114.

[0082] With the aid of the reed switch 150 and the switching transistor 144, the energy consumers of the electric apparatus 100 can be selectively disconnected from the battery 114 and connected to the battery 114. When the reed switch 150 is closed, a voltage drops via the two ohmic resistors 148, 152 connected in series. This has the result that the switching transistor 144 closes and thereby frees an electric connection between the voltage transformer 142 and the battery 114, so that the microcontroller 136, the Hall sensor 138 and the display device 140 can be supplied with electric energy. When the reed switch 150 assumes its open switching position, then no more electric current flows via the ohmic resistors 148 and 152 and the switching transistor 144 interrupts the electric connection between the battery 114 and the voltage transformer 142, so that the microcontroller 136, the Hall sensor 138 and the display device 140 cannot be provided with any more electric energy. The electric apparatus 100 thus has a usable operating mode, in which the reed switch 150 is closed and the energy consumers of the electric apparatus 100 are provided with electric energy. Furthermore, the electric apparatus 100 has a standby mode, in which the reed switch 150 is open and the energy consumers of the electric apparatus 100 are not supplied with electric energy. The standby mode forms a rest state in which the electric apparatus 100 consumes no electric energy at all.

[0083] The change from the standby mode into the usable operating mode is effected by closing the reed switch 150. The reed switch 150 is closed with the aid of the first permanent magnet 62, which forms an activation member arranged outside the electric casing 102 and movable back and forth by the user between a rest position and an activation position. In the rest position, the first permanent magnet 62 together with the free end of the pivot arm 60 assumes a position of maximum spacing from the reed switch 150, so that the field strength of the magnetic field provided by the first permanent magnet 62 prevailing at the location of the reed switch 150 is small. The rest position of the first permanent magnet 62 is present when the hand lever 48 rigidly connected to the first permanent magnet 62 undergoes no actuation by the user. When there is no actuation, the hand lever 48 is acted upon by the first restoring spring 58 with a spring-elastic restoring force, under the action of which the hand lever 48 dips into the handle aperture 44 and the first permanent magnet 62 assumes its rest position of maximum spacing from the reed switch 150. When the hand lever 48 is actuated by the user to free the flow path between the valve inlet 30 and the valve outlet 32, the first permanent magnet 62 is pivoted together with the pivot arm 60 into an activation position of maximum approach to the reed switch 150. In the activation position, the field strength of the magnetic field provided by the first permanent magnet 62 at the location of the reed switch 150 is sufficiently large so that the reed switch 150 changes into its closed switching position, and consequently the energy consumers of the electric apparatus 100 are supplied with energy via the switching transistor 144, and thus the usable operating mode of the electric apparatus 100 is activated.

[0084] An actuation of the hand lever 48 for freeing the flow connection between the valve inlet 30 and the valve outlet 32 thus has the result that the usable operating mode of the electric apparatus 100 is activated. The usable operating mode is maintained only as long as an actuation of the hand lever 48 takes place. When the user releases the hand lever 48 again, the electric apparatus 100 changes automatically into its standby mode, in which the electric apparatus 100 consumes no energy at all.

[0085] The display device 140 has, in the first advantageous embodiment of the invention illustrated in FIGS. 1 to 4, four light emitting diodes 154, 156, 158 and 160, which are mounted on the rigid printed circuit board 132. The light emitting diodes 154, 156, 158 and 160 are activated by the microcontroller 136 in dependence on the fluid pressure prevailing downstream of the valve seat 56. For this purpose, the measuring rod 94 forms in combination with the push part 80, the second restoring spring 92, the holding arm 82 and the second permanent magnet 86 and the Hall sensor 138, a pressure detecting device 162, by means of which the fluid pressure prevailing downstream of the valve seat 56 can be detected. In dependence on the fluid pressure mentioned, the second permanent magnet 86 approaches the Hall sensor 138, arranged in the electric casing 102, to a greater or lesser extent. The magnetic field provided by the second permanent magnet 86 can be detected by the Hall sensor 138 and a corresponding sensor signal can be evaluated by the microcontroller 136, which forms an evaluating device. Depending on the fluid pressure an activation of the light emitting diodes 154, 156, 158, 160 can then take place.

[0086] The light emitting diodes 154, 156, 158 and 160 provide the possibility of displaying a total of four different pressure ranges to the user. Depending on which of the pressure ranges the pressure currently prevailing downstream of the valve seat 56 in the through duct 34 comes under, the light emitting diode 154, 156, 158, 160 associated with the corresponding pressure range can be activated.

[0087] The electric apparatus 100 is separated galvanically from the remaining components of the spray gun 10. This facilitates the protection of current-carrying components from fluid, because all current-carrying components can be arranged in the electric casing 102 sealed against sprayed water, and electric contact elements via which the electric components arranged in the electric casing 102 are connected to components arranged outside the electric casing 102 can be omitted. To activate the usable operating mode the electric apparatus 100 is wirelessly and contactlessly connected to the activation member in the form of the first permanent magnet 62 arranged outside the electric casing 102, and for transmitting a signal corresponding to the fluid pressure currently prevailing downstream of the valve seat 56 in the through duct, the electric apparatus 100 is wirelessly and contactlessly connected to the second permanent magnet 86.

[0088] The current consumption of the electric apparatus 100 and therefore also its maintenance requirement is very low, since the electric apparatus 100 is in a current-consuming usable operating mode only when the user actuates the hand lever 48, otherwise the electric apparatus 100 is in a standby mode in which it consumes no energy.

[0089] In FIGS. 5, 6 and 7, a second advantageous embodiment of a spray gun according to the invention is shown schematically and is designated overall by the reference symbol 200. The spray gun 200 is configured largely identically to the spray gun 10 explained with reference to FIGS. 1 to 4. For identical components, therefore, in FIGS. 5, 6 and 7 the same reference symbols are used as in FIGS. 1 to 4 and reference is made to the above explanations with respect to these components to avoid repetition.

[0090] The spray gun 200 has, in the same way as the spray gun 10, an activation member arranged outside an electric casing sealed against sprayed water in the form of a first permanent magnet 62, which on actuation of the hand lever 48 is pivotable from a rest position into an activation position to activate a usable operating mode of an electric apparatus 202. The electric apparatus 202 comprises, like the above-explained electric apparatus 100, an electric casing 204 sealed against sprayed water, in which all the current-carrying components of the spray gun 200 are arranged.

[0091] In contrast to the spray gun 10, the spray gun 200 has no pressure detecting device. Instead, the electric apparatus 202 comprises a combined transmitting and receiving device in the form of a transceiver 206, with the aid of which signals can be wirelessly transmitted bidirectionally, preferably by radio, between the electric apparatus 202 and the high-pressure cleaning appliance, to which the spray gun 200 is connected. This provides the possibility of using a pressure sensor to measure the pressure of the conveyed fluid in the high-pressure cleaning appliance and to transmit a corresponding signal from the high-pressure cleaning appliance to the electric apparatus 202. Control commands can be transmitted from the electric apparatus 202 to the high-pressure cleaning appliance for setting a specific pressure range, which the user can select on a display device 208, preferably on a liquid crystal display. The display device 208 is mounted on a rigid printed circuit board 210 of the electric apparatus 202. On the display device 208 different cleaning parameter ranges can, for example, be displayed graphically to the user, from which the user can select a desired cleaning parameter range, for example, a specific pressure range. Additionally or alternatively, other information can be displayed graphically on the display device 208. In particular, a recommendation for a certain spray nozzle which can be connected when there is a specific pressure of the fluid supplied to the spray gun 200 can be displayed graphically on the display device 208 to the user. If a spray nozzle for discharging a mixture of fluid and a cleaning chemical is connected to the spray gun 200, different mixing ratios of the cleaning chemical can also be displayed on the display device 208, from which the user can select a desired mixing ratio.

[0092] To select a specific cleaning parameter range, the electric apparatus 202 has two input elements in the form of two input keys 212, 214, which are mounted directly on the single rigid printed circuit board 210 of the electric apparatus 202. The input keys 212, 214 are each associated with an operating element in the form of a tumbler 216, 218. The tumblers 216, 218 axe mounted on the electric casing 204 pivotably about a common pivot axis 220. The two tumblers 216, 218 each have a user interface 222, 224 which is inclined to a plane which is defined by the display device 208. This facilitates operation of the electric apparatus for the user, because the display device 208 mounted on the rigid printed circuit board 210 can be inclined at a different angle to the longitudinal axis 226 of the spray gun 200 than the user interfaces 222, 224, by providing the tumblers 216, 218. The longitudinal axis 226 of the spray gun 200 is in this case predetermined by the longitudinal direction of the outlet conduit 22.

[0093] Provision may be made, for example, for the display device 208 together with the rigid printed circuit board 210 to be inclined at a significantly smaller angle to the longitudinal axis 226 than the user interfaces 222, 224. The inclination of the display device 208 to the longitudinal axis 226 may, for example, be 10 to 50°, preferably 30°, and the inclination of the user interfaces 222, 224 to the longitudinal axis 226 may, for example, be 60 to 80°, preferably 70°. This makes it easier for the user to read information displayed on the display device 208, and to operate the input keys 212, 214 by means of the tumblers 216, 218, because the user can view the display device 208 from above on use of the spray gun 200. With one hand he can grip the handle 38 of the spray gun 200, it being possible for him to actuate the hand lever 48 with his fingers and a desired user interface 222 or 224 with his thumb. The user interfaces 222, 224 are arranged for this purpose at the upper end of the handle 38 facing the rear casing half 120 of the electric casing 204. The spray gun 200 can thus be operated by the user with one hand and the user can easily read information on the display device 208.

[0094] The two input keys 212, 214 of the electric apparatus 202 have not only the function of inputting control commands of the electric apparatus 202, but in addition they form activation members which are arranged in the electric casing 204 and with the aid thereof a usable operating mode of the electric apparatus 202 can be activated. This gives the user of the spray gun 200 the option to activate a usable operating mode of the electric apparatus 202 selectively either by actuating the hand lever 48, as has already been explained in detail above with reference to the spray gun 10, or by actuating one of the user interfaces 222, 224 which are each coupled to an input key 212, 214.

[0095] A schematic block diagram of the electric apparatus 202 is shown in FIG. 7. In a corresponding manner to the above-explained electric apparatus 100, the electric apparatus 202 also has a microcontroller 228 and a voltage transformer 230. Via a switching transistor 232, the voltage transformer 230 is connected to the positive pole of a battery 234. A control input 236 of the switching transistor 232 is, via a first ohmic resistor 238 and a Schottky diode 240 series-connected to the first ohmic resistor 238, in electric connection with a reed switch 242 which is connected to an earth potential. Via a second ohmic resistor 244, the control input 236 of the switching transistor 232 is connected to the positive pole of the battery 234. When the first permanent magnet 62 of the spray gun 200 is pivoted by the user by actuating the hand lever 48 from its rest position into its activation position, it approaches the reed switch 242 arranged in the electric casing 204, so that this switch assumes its closed switching position. The closing of the reed switch 242 has the result that, via the two ohmic resistors 238, 244 and the Schottky diode 240, a current can flow, which leads to a corresponding voltage drop, so that the switching transistor 232 switches through and thereby frees the electric connection between the positive pole of the battery 234 and the input of the voltage transformer 230. Via the voltage transformer 230, the microcontroller 228 is supplied with electric energy.

[0096] In contrast to the above-explained electric apparatus 100, the electric apparatus 202 has, in addition to the reed switch 242, a self-locking member in the form of a second switching transistor 246 whose control input 248 is connected to the microcontroller 228. In a corresponding manner to the reed switch 242, the second switching transistor 246 also enables the control input 236 of the first switching transistor 232 to be connected to earth potential, so that the first switching transistor 232 can be switched through not only by closing the reed switch 242 but also by controlling the second switching transistor 246.

[0097] The second switching transistor 246 provides the microcontroller 228 with the possibility of still maintaining the usable operating mode of the electric apparatus 202, after the opening of the reed switch 242, for a predetermined period of time. For this purpose, the microcontroller 228 has a timer 250 which is activated when the reed switch opens 242. For this purpose, the reed switch 242 is connected via a first input line 252 to the microcontroller 228, a second Schottky diode 254 being connected to the first input line 252. The opening of the reed switch 242 can thus be detected by the microcontroller 228. This has the result that the timer 250 is started, so that the electric connection between the battery 234 and the current consumers of the electric apparatus 202 is still maintained for a predetermined period of time, which may amount to several seconds or even several minutes. After the predetermined period of time has elapsed, the second switching transistor 246 closes and this in turn has the result that the first switching transistor 232 interrupts the electric connection between the positive pole of the battery 234 and the input of the voltage transformer 230. The electric apparatus 202 thus automatically assumes its standby mode after the predetermined period of time has elapsed.

[0098] As already mentioned, an activation of the usable operating mode of the electric apparatus 202 can be carried out not only by means of the first permanent magnet 62 but also by actuating the input key 212 or the input key 214. As is apparent from FIG. 7, the input keys 212, 214 enable a connection of the control input 236 of the first switching transistor 232 to earth potential in the same way as the reed switch 242. If, instead of the reed switch 242, one of the input keys 212, 214 is closed, this also results in the first switching transistor 232 freeing the electric connection between the positive pole of the battery 234 and the input of the voltage transformer 230, so that the electric apparatus 202 changes into its usable operating mode. The input key 212 is connected via a second input line 256 to the microcontroller 228, and the input key 214 is connected via a third input line 258 to the microcontroller 228. Via the second input line 256 and the third input line 258, the microcontroller 228 thus receives a signal which indicates to it which input key was actuated. When the input key is released again, this is detected by the microcontroller 228 based on the signal transmitted via the respective input line 256, 258 and then the timer 250 can be activated in the same way as on the opening of the reed switch 242, so that the usable operating mode of the electric apparatus 202 is still maintained for a predetermined period of time.

[0099] The electric apparatus 202 may be preassembled in the same way as the electric apparatus 100, the electric casing 202 is configured sealed against sprayed water and can be mounted during the assembly of the spray gun 200 in a simple manner on the gun casing 12 of the spray gun 200. The electric apparatus 202 also has a very low energy consumption, since the current consumers of the electric apparatus 202 are only supplied with electric energy when a use of the spray gun 200 takes place.