Handheld device for the application of an abrasive material to a surface

Abstract

The present invention pertains to a handheld device for the application of an abrasive material to a surface, in particular for sandblasting. The invention also pertains to the use of a handheld device for the application of an abrasive material to a surface. The invention also pertains to a method for applying an abrasive material, in particular sand blasting, with a handheld device for the application of an abrasive material to a surface.

Description

[0001] “Handheld device for the application of an abrasive material to a surface”

[0002] FIELD OF THE INVENTION

[0003] The present invention pertains to a handheld device for the application of an abrasive material to a surface, in particular for sandblasting. The invention also pertains to the use of a handheld device for the application of an abrasive material to a surface. The invention also pertains to a method for applying an abrasive material, in particular sand blasting, with a handheld device for the application of an abrasive material to a surface.

[0004] BACKGROUND OF THE INVENTION

[0005] Abrasive treatment of surfaces by application of abrasive material, particularly sand or other grains, is often referred to as sandblasting. By this treatment, existing layers of a surface are either partly or completely removed by the impact of the applied particles.

[0006] The application of the particles is commonly achieved by either blasting or throwing the particles onto the intended surface. Especially for handheld devices, blasting is inferior to throwing due to the required compressor, which imposes a heavy weight. Such heavy weight leads to eventual exhaustion of the user. In addition, such equipment often has a pipe or hose to guide the abrasive to the nozzle. Such a pipe or hose constitutes a tripping hazard.

[0007] From WO 2020 / 038605, a handheld device for the application of an abrasive material to a surface, particularly a sandblasting device, is known. This device comprises a rotary blasting wheel which accelerates abrasive particles to be applied onto a surface. It also comprises a recipient containing the particles. Said recipient comprises an actuator, acting upon a movable piston, causing the particles to move towards the rotary blasting device. However, depending on the orientation of the device with respect to Earth’s field of gravity, the particle flow from the recipient to the rotary blasting device might be disturbed. This prevents the use of the device in certain orientations, such as an overhead use.

[0008] SUMMARY OF THE INVENTION

[0009] Given this background, the problem to be solved by the invention is to provide a device for the application of an abrasive material onto a surface with an improved user- friendliness and a better utility in hard-to-reach positions.

[0010] This problem is solved by the device according to claim 1 , the use according to claim 14 and the method according to claim 15. Preferred embodiments are given in the subordinate claims and the description following hereafter.

[0011] The basic concept of the device according to the invention is to have a storage device for holding the particles, which is positioned above the particle accelerator device in relation to the Earth's gravity field, regardless of the orientation of the particle blasting device. This enables the user to use the device in all possible positions and orientations, including overhead applications.

[0012] According to a first aspect of the invention the problem is solved by a portable, handheld device for the application of an abrasive material to a surface, in particular for sand blasting, wherein the device comprises at least one rotary impeller for accelerating the abrasive material, the impeller being held within a protective impeller housing comprising an inlet channel and an exit opening, wherein the device further comprises a container module for storing and providing the abrasive material, the container module comprising a container with at least one opening and a connecting element for fluidly connecting the at least one opening to the protective impeller housing, wherein the container is, in particular tiltably and / or pivotably, moveable with respect to the impeller.

[0013] When the container is moveable with respect to the impeller, it can be positioned in such a way that the abrasive material flows to the impeller by gravitational force during its entire path from the container to the impeller, as such granting a better utility regardless of the orientation of the device. A tiltable moveability can be achieved with particular low effort, while a pivotable moveability offers the highest level of freedom and hence a high utility of the device. A tiltable movement can be a rotary movement around a rotational axis, i.e. the trajectories of points of the moving body in question that are along a line parallel to said axis are also parallel to each other. A special form of a tiltable movement according to this definition is a spinning motion, where the rotational axis can be essentially equal to the main axis of a body, wherein the main axis can be the axis along the longest extension of the body. In contrast, a pivotable movement denotes a movement of a body wherein the trajectories of all points belonging to said body can rotate around the same point, also known as pivot point.

[0014] The device according to the invention is designed for the application of an abrasive material to a surface. In particular, the device can be designed for sandblasting. Sandblasting can be the operation of forcibly propelling a stream of abrasive material against a surface under high pressure or velocity to smooth a rough surface, roughen a smooth surface, shape a surface and / or remove surface contaminants, such as paint or rust. The abrasive material can be of any kind, size, and mechanical properties. In particular, the abrasive material can be of natural or artificial origin, and of organic and inorganic material.

[0015] The device according to the invention comprises an impeller. The impeller can be a rotor used to increase the kinetic energy of matter by acceleration of the matter or by increasing its pressure. In one embodiment of this invention, the impeller can comprise a rotary drive shaft and at least one fin, preferably several fins, for receiving and accelerating the particles. Having several fins for receiving and accelerating the particles can enable a more homogenous distribution of the load and also a more homogenous particle stream to be applied onto the surface to be treated.

[0016] During use of the blasting device, the impeller can preferably rotate at a speed range between 3,000 and 30,000 rotations per minute. This can allow for a particularly efficient application of the particles on the surface. However, the impeller can also rotate at lower or higher rotational speeds. The device can comprise a speed regulator for adjusting the rotational speed of the impeller. In a preferred embodiment, it can be that the speed regulator can adjust the speed in different, distinct steps.

[0017] The housing can surround the impeller at least partially and can be intended to guide the particles in the required direction for application and to prevent particles leaving the impeller from harming the user or other subjects or objects unintendedly. The housing can hereby be of any material, particularly of a metal or plastic material. The housing can surround the impeller to one or more sides, particularly to one, two, three, four, five or all six sides. In one particular embodiment, parts of the housing can also be attached to the impeller. The housing can comprise several openings. According to the invention, the housing comprises at least one inlet channel and one exit opening, wherein the inlet channel can allow particles to enter the housing and thus the impeller and the exit opening can allow accelerated particles to leave the housing and be directed against the surface to be treated.

[0018] The housing can also serve as a protective guard for the end user’s safety by preventing access to the impeller. In such an embodiment, the exit opening can be of a sufficiently narrow size to prevent access by the fingers or other extremities of the end user.

[0019] The inlet channel can be a channel in is literal meaning. However, it can also be a channel of any size and length, and in particular can be a mere hole in the wall of the protective housing. The inlet channel can be any device or means that can provide a guiding for the particles entering the housing to the impeller in order to be accelerated.

[0020] The term “container module” can refer to the container itself and the connecting element. The connecting element can be any device that is used to connect the container fluidly to the remainder of the device for the application of an abrasive material to a surface.

[0021] The container can be of any shape and condition that is feasible for storing the abrasive material. In a preferred embodiment, the container can be waterproof for keeping the abrasive material dry in order to prevent clumping. In one embodiment, the container can have a generally circular cross-section. In one embodiment, the container can be made of plastic or metal.

[0022] The connecting element according to the invention is for fluidly connecting the at least one opening of the container to the protective impeller housing. In one embodiment, the connecting element can fluidly connect the container to the inlet channel of the impeller housing. In one embodiment, the connecting element can form at least a part of the inlet channel. In another embodiment, it can be that the inlet channel is not part of the connecting element. In one embodiment, the connecting element can be connected to the inlet channel by any means that is known to the person skilled in the art and that can provide a fluid connection.

[0023] In one embodiment, the movement of the container with respect to the impeller can be realized by the connecting element, wherein in particular the connecting element can comprise a pivot element to realize the movement of the container with respect to the impeller, wherein preferably the pivot element can be a bearing.

[0024] Using the connecting element to realize the movement of the container can be a particular efficient solution, as it can represent a dual-use of the connecting element both for the fluidly and mechanical connection between the container and the impeller. For example, it also can ensure that the container, while being moveable, can be still fixed in its distance to the remainder of the blasting device and does not need any additional support.

[0025] If the connecting element can comprise a pivot element, the moveability of the container can be particularly simple because the pivot element can fix the container and can only provide the degrees of freedom that can be required. The design of the pivot element as a bearing can constitute a cost-efficient solution and the ability to use standardized components. This can be any kind of bearing, for example, but not limited to, plain bearings, ball bearings or roller bearings.

[0026] A pivot element can be any element that guides one object in a pivotable and / or tiltable movement with respect to another object.

[0027] In one embodiment, the movement of the container with respect to the impeller can be realized by the connecting element, wherein in particular the connecting element can comprise a rotational element to realize the movement of the container with respect to the impeller, wherein preferably the rotational element can be a bearing. A rotational element can be configured to rotate the container around the rotational axis of the impeller or around an axis parallel to the rotational axis of the impeller.

[0028] In one embodiment, it can be that the connecting element is a semi-rigid or flexible tube. The semi-rigid or flexible tube can for example be a gooseneck.

[0029] In an embodiment, the connection element, can be a semi-rigid or flexible tube, a pivot element and / or a rotational element.

[0030] In an embodiment, the connecting element can comprise a first pivot element, wherein the first pivot element can be configured to enable a tilting motion of the container around a first tilt axis, wherein preferably the first pivot element can be a spherical, axial and / or radial bearing.

[0031] This can provide the advantage of a particularly easy mean for making the container moveable with respect to the impeller.

[0032] A pivot element can be any element that connects two or more objects and enables a pivotable or tiltable movement of these objects with respect to each other.

[0033] A bearing can be a machine element that constrains relative motion to only the desired motion, and can reduce friction between moving parts. A spherical bearing can enable a spherical rotation and can be a ball or socket joint. An axial bearing can be a bearing that supports axial forces, while a radial bearing can be a bearing that supports radial loads. In an embodiment, the device can comprise a second pivot element, in particular a second bearing, wherein in particular the second pivot element can be configured to enable a tilting motion of the container around a second tilt axis, wherein in particular the second tilt axis can be essentially perpendicular to the first tilt axis, wherein preferably the second pivot element can be an axial bearing.

[0034] Hereby, movement can be enabled in several directions and / or around several rotational axes.

[0035] In further embodiments, the connecting element can also comprise three or more pivot elements.

[0036] In one embodiment, the container can be fixable in at least one position, in particular steplessly.

[0037] This can allow a convenient use of the blasting device, while ensuring the concept of the invention of a container that is located above the impeller during use.

[0038] A stepless fixation can mean that the container can be fixed in any position to which it can be moved. In one embodiment, it can be that the container can be fixed to at least one position and can be moveable, in particular pivotable and / or rotatable.

[0039] In one embodiment, the container can be fixable by means of a lever, a switch or another manipulation means, preferably that the container can be fixable by frictional force.

[0040] This can ensure a convenient and user-friendly fixation of the container, especially when the orientation of the blasting device changes during use, leading to a high frequency of changing the orientation of the container.

[0041] However, any other manipulation means to trigger the fixation by a user can be disclosed in this invention as well. In a further embodiment, the fixation can be triggered by a controlling device and as such not by immediate interaction with a user.

[0042] The fixation of the container can be by any type of force. For example, in one embodiment the container can comprise recesses and the manipulation means can comprise a corresponding bolt which locks the container when the recess and the bolt can interlock.

[0043] It can also be that the lever, switch or other manipulation means of one embodiment of the present invention can be configured to exert a force onto a frictional element in such a way that the frictional element can get into frictional contact with at least some part of the container, the connecting element or any other part of the blasting device in such a way that a movement of the container can be blocked by friction. Herein, the frictional force can or cannot be created by a part of the lever, switch or other manipulation means. In yet another embodiment, the fixation can be further realized by a force other than frictional force.

[0044] In one embodiment, the container could be fastened to and unfastened from the connecting element in a non-destructive way, preferably by a Bayonet connector.

[0045] This can allow the user to readily change the container when it is empty or to adapt the abrasive material to the current task, as such enhancing the user-friendliness. A Bayonet-Connector can be a particularly efficient solution, as it can allow a fastening or unfastening of the container with very little effort.

[0046] A non-destructive way can be any way that does not alter the individual parts of the blasting device, in particular, the container or the connecting element.

[0047] However, other types of connectors are also thinkable, such as, but not limited to, clip connections, screws or other form-fitting or force-fitting connections.

[0048] In one embodiment, the device, in particular the connecting element, can comprise an information obtaining element that can be configured to obtain an information, particularly electronically and / or mechanically, wherein said information can be carried by the device, in particular by the attached container, wherein preferably the obtained information can be at least partially referring to the characteristics of the container and / or the content thereof.

[0049] This can bring about the advantage of an enhanced user-friendliness and also of an improved security for the user, as it can reduce misuse by the user.

[0050] When the information obtaining element can be comprised by the connecting element, information referring to the container can be particularly easy obtained. When the information can be carried by the container, information referring to the container can be particularly efficiently acquired and stored.

[0051] Information obtained in such a way can be used to adapt a control system of the blasting device according to the contents of the container, particularly of the type or particle size of the abrasive material or the filling level of the container.

[0052] The information can comprise the type of abrasive material contained in the container, the volume of the material, a container identification information, or other means for identifying the container type and preventing the application of a non-fitting container or other harm done by misuse. The information obtaining element can, in one embodiment, be an electronic device, in particular, it can be a data chip. In one embodiment, the information can be carried by an information carrying element. The information carrying element can, in one embodiment, be an electronic device, in particular, it can be a data chip. It can be that the information carrying element can be fixed to the container. However, it can also be that the information carrying element is detachable from the container. In particular, it can be that the information carrying element is fixed or detachably attached to any part of the sand blasting device.

[0053] In one embodiment, the connecting element can comprise a means for removing at least a part of a sealing of the container, such that a sealing of the opening of the container can be partly, particularly entirely, removed upon the first attachment of the container.

[0054] This way, it can be that the user is not required to remove such a sealing of the container itself, which can increase the user-friendliness and can also ensure that the user cannot forget to remove the sealing or cannot remove it incorrectly. It can also allow a more efficient use of the blasting device because the attachment of a new container can be performed without prior removal of the sealing.

[0055] “Upon the first attachment of the container” herein can mean that the means for removing the sealing removes the sealing, at least partially, of a container when this specific container can be brought into connection with the connecting element for the first time.

[0056] The sealing can be for preventing the content, particularly the abrasive material, from leaving the container. The sealing can also be for preventing unsought matter, such as humidity, dust or other contaminations from entering the container and harming the abrasive material. However, for example the existence of such a means to break the sealing cannot be tied to the container comprising a sealing. It is also thinkable that the connecting element can comprise a means for breaking or otherwise opening the sealing when used with a container that does not comprise a sealing.

[0057] In one embodiment, the container can comprise an air inlet to allow an air flow into the container during use.

[0058] Such an air inlet can allow air from the surrounding atmosphere to enter the container and to replace the volume that was previously taken by the abrasive material when said abrasive material can leave the container upon use of the blasting device. The air inlet can be of any type that can allow air to enter the container. The air inlet can be a simple hole, but it can also comprise a valve, a membrane or similar. The air inlet can also comprise means to prevent other matter, such as dust or dirt, from entering the container. That way, the abrasive material can be prevented from contamination. The concept of the present invention is that the container is moveable with respect to the impeller, so that the container can always be located above the impeller and gravity can ensure the material flow of the abrasive material to the impeller. However, in one embodiment, the container can also comprise a pushing element for pushing the abrasive material to the inlet channel. This pushing element can assert a pressure on the abrasive material, so that it can flow towards the inlet channel and to the impeller. In a further embodiment, the pushing element can be driven by a spring. The spring can be of any type, in particular, the spring is a coil spring or a gas spring.

[0059] In one embodiment, the container can comprise a further opening for filling abrasive material into the container, preferably in that the further opening can be covered by a lid, further preferably that the lid can be friction-locked to the container, particularly that the lid can be connected to the container by a hinge.

[0060] This can enable an easy refill of the container during prolonged use, without the need to change the container when it is empty.

[0061] A lid can be any device that can cover the opening and can prevent abrasive material from leaving the container through the particular opening that can be covered by said lid. A hinge can be any means for connecting two objects together while pertaining at least one degree of movement between said objects. A hinge can comprise a bearing, preferably a radial bearing.

[0062] In one embodiment, the device can comprise a mass flow control means to control the mass flow of abrasive material from the container to the impeller via the inlet channel, wherein in particular the mass flow can be controlled by an adjustment of the crosssection of the inlet channel, wherein in particular the mass flow control means can comprise a rotary knob.

[0063] Such a mass flow control means, particularly a rotary knob, can allow for an easy adjustment of the removal rate and hence also of the amount of roughness induced to the processed surface.

[0064] The mass flow control means can be of any type that is suitable to control and / or adjust the mass flow of abrasive material through the inlet channel. For example, the adjustment of the inlet channel does not necessarily require changing the cross-section of the entire inlet channel. It can be sufficient to change the cross-section and at least one point of the inlet channel. A rotary knob can be used to adjust the mass flow, in particular by adjusting the cross-section, of abrasive material from the container to the impeller via the inlet channel. The cross-section can be the section of the inlet channel with the smallest diameter. For example, the cross-section can be the minimal cross-section of the whole inlet channel.

[0065] In one embodiment, the impeller can comprise an impeller core and at least one fin for accelerating the abrasive material, wherein the at least one fin can be formed separately from the impeller core, wherein in particular the impeller core and the at least one fin can be made of different materials.

[0066] This way, the components of the impeller can be designed to each suit best its specific task, i.e. the core can be designed to bear large mechanical loads, while the at least fin can be designed to withstand the wear induced by the abrasive material for a longer time. It can also allow for an easy replacement of the at least one fin when an excessive amount of wear has accumulated.

[0067] The at least one fin can be of a straight shape, but also feature a curved form. It is also possible that the at least one fin has a tubular shape. The at least one fin can be attached, in particular detachably, to the impeller core. In one particular embodiment, the impeller core and the at least one fin can be made of different materials. For instance, the core can be made of a particularly tough material, while the at least one fin can be made of a material with high wear resistance or with a low density. The at least one fin can be a vane and / or a blade.

[0068] In one embodiment, the impeller can be fastened detachably within the impeller housing, wherein in particular the impeller housing can be openable for the assembly and disassembly of the impeller.

[0069] This can allow an easy replacement of a worn impeller without discarding the entire blasting device.

[0070] The opening and closing of the impeller housing can be of any kind. In some embodiments, the impeller housing can be made of two parts that can be separated or the impeller housing can comprise a lid. In another embodiment, the impeller housing can be configured to be removeable as a whole, as such revealing the impeller for ready removal.

[0071] In one embodiment, the impeller can be mechanically connected to, and driven by, a power drive, particularly an electric engine, and the power drive can be fed by an energy storage device, particularly an accumulator.

[0072] This can allow for an easy use of the blasting device without it being connected to a wirebound energy supply. The power drive can be of any type, but in one embodiment, the power drive can be an electrical power drive, for instance an electrical engine, particularly an AC motor or a DC motor. The energy storage system can also be of any type, but preferably provides the type of energy the power drive can require. In one embodiment, the power drive can be a DC motor and the energy storage device can be an electric battery. In one embodiment, the energy storage device can be a compressed air tank and the power drive can be a respective air engine.

[0073] In one embodiment, the energy storage device can be detachably mounted to the device.

[0074] This can allow the energy storage to be charged with energy once the energy stored in the energy storage device can be depleted. For example, the energy storage can be detached by a user and applied to a charging device. It is also possible that the blasting device can comprise more than one energy storage device, so that a second energy storage device can be attached while the first energy storage device can be charged with energy.

[0075] In one embodiment, the blasting device can comprise a motor control means, wherein the motor control means can be configured to control the motor. In a further preferred embodiment, the motor control means can be configured to control the motor in such a way that the impeller can be prevented from moving before the container can be detached.

[0076] This can have the advantage of an increased security of the device, as it can prevent injuries, particularly hand injuries, of a userwho detaches the container while the impeller is still moving.

[0077] In one embodiment, the mass flow control means and the motor control means can be configured to be coupled in such a way that the mass flow is interrupted before the motor stops.

[0078] This can bring about the advantage that no abrasive material is left in the inlet channel or within the impeller housing when the blasting device is stopped. In doing so, the impeller can be restarted without any abrasive material inside the impeller. Thus, no abrasive material can block the impeller, so that the restart of the impeller can be smooth and efficient.

[0079] In one embodiment, the blasting device can comprise a handle for the user to hold the device. This can allow for a particularly easy use of the blasting device.

[0080] The invention also relates to the use of a device for applying an abrasive material onto a surface, in particular for sand blasting, wherein the center of gravity of the abrasive material within the container can be located above the inlet channel with respect to the earth’s center of gravity during use.

[0081] This can ensure that the abrasive material flows from the container to the impeller via the inlet channel predominantly by gravitational force.

[0082] The center of gravity of the abrasive material can refer to the abrasive material that can be held within the container. It can as such be the center of gravity of the combined and weighted mass of all particles of the abrasive material located within the container.

[0083] The invention also relates to a method for applying an abrasive material, in particular sand blasting, with a device for applying an abrasive material onto a surface.

[0084] Other objects, features, advantages and aspects of the present invention will become apparent to those skilled in the art from the following description and appended claims. It should be understood, however, that the following description, appended claims, and specific examples, which indicate preferred embodiments of the application, are given by way of illustration only. Various changes and modifications within the spirit and scope of the disclosed invention will become readily apparent to those skilled in the art from reading the following.

[0085] DEFINITIONS

[0086] As used herein, the following expressions are generally intended to preferably have the meanings as set forth below, except to the extent that the context in which they are used indicates otherwise.

[0087] The expression "comprise", as used herein, besides its literal meaning also includes and specifically refers to the expressions "consist essentially of" and "consist of'. Thus, the expression "comprise" refers to embodiments wherein the subject-matter which "comprises" specifically listed elements does not comprise further elements as well as embodiments wherein the subject-matter which "comprises" specifically listed elements may and / or indeed does encompass further elements. Likewise, the expression "have" is to be understood as the expression "comprise", also including and specifically referring to the expressions "consist essentially of' and "consist of'. The term "consist essentially of", where possible, in particular refers to embodiments wherein the subject-matter comprises 20% or less, in particular 15% or less, 10% or less or especially 5% or less further elements in addition to the specifically listed elements of which the subject-matter consists essentially of. FIGURES

[0088] Figure 1 shows an exemplary blasting device in a sectional view.

[0089] Figure 2 shows a detail of the connecting element.

[0090] Figure 3 shows a detail of the impeller.

[0091] Figure 4 shows an exemplary blasting device.

[0092] Figure 5 shows an exemplary blasting device.

[0093] Figure 6 shows an exemplary blasting device.

[0094] DETAILED DESCRIPTION OF THE INVENTION

[0095] Figure 1 shows an exemplary blasting device 1 in a sectional view.

[0096] The portable, handheld device 1 for the application of an abrasive material 3 to a surface 24, in particular for sand blasting according to the invention comprises at least one rotary impeller 2 for accelerating the abrasive material 3. The impeller 2 is held within a protective impeller housing 4 comprising an inlet channel 5 and an exit opening 6. The device 1 further comprises a container module 7 for storing and providing the abrasive material 1 . The container module 7 comprises a container 8 with at least one opening 9 and a connecting element 10 for fluidly connecting the at least one opening 9 to the protective impeller housing 4. The container 8 is moveable with respect to the impeller 2. The container 8 may have several degrees of freedom. In particular, the container 8 may be tiltably and / or pivotably moveable with respect to the impeller 2.

[0097] In one example, during use the abrasive material 3 flows from the container 8 through the opening 9 and the inlet channel 5 into the chamber formed by the housing 4 and onto the impeller 2. The impeller 2 is set into a rotating motion so that the abrasive material 3 can be captured and accelerated by the fins 20 of the impeller 2. The accelerated particles of abrasive material 3 then exit the housing 4 through the exit opening 6 in a particle stream. This stream of particles can be directed by a user to a surface 24 to be machined.

[0098] The movement of the container 8 with respect to the impeller 2 is realized by the connecting element 10. The connecting element 10 comprises a pivot element 11 to realize the movement of the container 8 with respect to the impeller 2. The pivot element 11 is a bearing.

[0099] The connecting element 10 comprises a first pivot element 11 , wherein the first pivot element 11 is configured to enable a tilting motion of the container 8 around a first tilt axis, wherein the first pivot element 11 is a spherical, axial and / or radial bearing.

[0100] In an embodiment not shown in the Figures, the device comprises a second pivot element, in particular a second bearing. The second bearing is here configured to enable a tilting motion of the container around a second tilt axis . The second tilt axis is essentially perpendicular to the first tilt axis. In a further embodiment not shown in the figures, the second pivot element is an axial bearing.

[0101] The connecting element 10 in one example shown in Figure 2 comprises two arms 10a, 10b that are connected to the container 8 by a connecting means. The connecting means may comprise or consist of a pivot element 11 , particularly by a bearing 12, to allow a movement of the container 8 relative to the impeller 2. The bearing 12 is preferably a plain bearing.

[0102] The container 8 is fixable in at least one position. Here, it is steplessly fixable.

[0103] The container 8 is fixable by means of a lever 13, a switch 13 or another manipulation means 13. Here, the container 8 is fixable by frictional force.

[0104] The container 8 can be fastened to and unfastened from the connecting element 10 in a non-destructive way. For this purpose, the connecting element 10 and the container 8 each comprise corresponding parts for a Bayonet connection.

[0105] The connecting element 10 comprises an information obtaining element 14 to obtain an information, particularly electronically and / or mechanically, that is carried by the attached container 8. The obtained information is at least partially referring to the characteristics of the container 8 and / or the content thereof.

[0106] The at least one opening 9 can be closed by a sealing (not shown). To allow a flow of abrasive material 3 out of the container 8 to the impeller 2 via the inlet channel 5, the connecting element 10 comprises a means 15 for removing at least a part of a sealing of the container, such that a sealing of the opening 9 of the container 8 is partly or entirely removed upon the first attachment of the container 8.

[0107] The container 8 comprises an air inlet 16 to allow an air flow into the container 8 during use. In an embodiment shown in Figure 4, the container 8 comprises a further opening 27 for filling abrasive material 3 into the container 8. The further opening is here covered by a lid 28. The lid 28 is here friction-locked to the container 8. In an embodiment not shown in the Figures, the lid 28 is connected to the container by a hinge.

[0108] The blasting device 1 comprises a mass flow control means 17 to control the mass flow of abrasive material 3 from the container 8 to the impeller 2 via the inlet channel 5. The mass flow is controlled by an adjustment of the cross-section of the inlet channel 5. The mass flow control means 17 comprises a rotary knob 18.

[0109] The impeller 2 comprises an impeller core 19 and at least one fin 20 for accelerating the abrasive material 3. In one example shown in Figure 3, the impeller 2 comprises four fins 20 . The at least one fin 20 is formed separately from the impeller core 19. The impeller core 19 and the at least one fin 20 are made of different materials.

[0110] The impeller 2 is fastened detachably within the impeller housing 4. The impeller housing 2 is openable for the assembly and disassembly of the impeller 2.

[0111] The impeller 2 is mechanically connected to and driven by a power drive 21 . The power drive is an electric engine. The power drive 21 is fed by an energy storage device 22. Here, the energy storage device is an accumulator.

[0112] The energy storage device 22 is detachably mounted to the device 1 .

[0113] For reasons of durability and electrical safety, the electrical engine 21 is held within a separate housing to isolate it from the abrasive material 3 within the impeller housing 2. This motor housing is mechanically connected to the housing 2.

[0114] A handle 23 is disposed upon the motor and impeller housing 2, enabling a safe grip of the device 1 , and the necessary control required to aim the released abrasive material at the surface 24 to be treated.

[0115] A trigger 25 to safely switch the device on and off is disposed within at least one of the handles 23.

[0116] A safety lock lever 26 is disposed adjacent to the trigger 25 to prevent accidental operation of the device 1 . The lock lever 26 is activated to move an additional mechanical or electrical switch to allow the electrical engine 21 to drive the impeller 2. The lock lever 26 also activates a mechanical flow control device. The mechanical flow control device allows a flow of abrasive material 3 through the inlet channel 5. The mass flow control means 17 restricts the operational range of the mechanical flow control device and as such limits the cross section of the inlet channel 5 when the mechanical flow control device is ’’open”. Therefore, once the lock lever 26 is activated and the desired flow rate is set by use of the mass flow control means 17, no further action is required for the end user to release the abrasive material 3 into the impeller 2 but to operate the trigger 25.

[0117] The device 1 is used for applying abrasive material 3 onto a surface. Due to the moveability of the container 8 relative to the impeller 2, the center of gravity of the abrasive material 3 is located above the inlet channel 5 with respect to earth’s center of gravity during use.

[0118] A method for applying an abrasive material 3, in particular sand blasting, according to the invention uses a blasting device shown in the above description or as defined by the corresponding claims.

[0119] Figure 5 shows an exemplary blasting device 1.

[0120] The portable, handheld device 1 for the application of an abrasive material 3 to a surface 24, in particular for sand blasting according to the invention comprises at least one rotary impeller 2 for accelerating the abrasive material 3. The impeller 2 is held within a protective impeller housing 4 comprising an inlet channel 5 and an exit opening 6. The device 1 further comprises a container module 7 for storing and providing the abrasive material 1 . The container module 7 comprises a container 8 with at least one opening 9 and a connecting element 10 for fluidly connecting the at least one opening 9 to the protective impeller housing 4. The container 8 is moveable with respect to the impeller 2. The container 8 may have several degrees of freedom. In particular, the container 8 may be tiltably and / or pivotably moveable with respect to the impeller 2.

[0121] The movement of the container 8 with respect to the impeller 2 is realized by the connecting element 10. The connecting element 10 is a semi-rigid or flexible tube. The semi-rigid or flexible tube is a gooseneck.

[0122] Figure 6 shows an exemplary blasting device 1.

[0123] The portable, handheld device 1 for the application of an abrasive material 3 to a surface 24, in particular for sand blasting according to the invention comprises at least one rotary impeller 2 for accelerating the abrasive material 3. The impeller 2 is held within a protective impeller housing 4 comprising an inlet channel 5 and an exit opening 6. The device 1 further comprises a container module 7 for storing and providing the abrasive material 1 . The container module 7 comprises a container 8 with at least one opening 9 and a connecting element 10 for fluidly connecting the at least one opening 9 to the protective impeller housing 4. The container 8 is moveable with respect to the impeller 2. The container 8 may have several degrees of freedom. In particular, the container 8 may be tiltably and / or pivotably moveable with respect to the impeller 2. The movement of the container 8 with respect to the impeller 2 is realized by the connecting element 10, wherein the connecting element 10 comprises a rotational element to realize the movement of the container 8 with respect to the impeller 2. The rotational element is a bearing. The rotational element is configured to rotate the container 8 around the rotational axis of the impeller 2 or around an axis parallel to the rotational axis of the impeller 2.

Claims

CLAIMS1 . A portable, handheld device for the application of an abrasive material to a surface, in particular for sand blasting,- wherein the device (1) comprises at least one rotary impeller (2) for accelerating the abrasive material (3), the impeller (2) being held within a protective impeller housing (4) comprising an inlet channel (5) and an exit opening (6),- wherein the device (1) further comprises a container module (7) for storing and providing the abrasive material (1), the container module (7) comprising a container (8) with at least one opening (9), and a connecting element (10) for fluidly connecting the at least one opening (9) to the protective impeller housing (4), characterized in that the container (8) is, in particular tiltably and / or pivotably, moveable with respect to the impeller (2).

2. Device according to claim 1 , characterized in that the movement of the container (8) with respect to the impeller (2) is realized by the connecting element (10), wherein in particular the connecting element (10) comprises a pivot element (11) to realize the movement of the container (8) with respect to the impeller (2), wherein preferably the pivot element (11) is a bearing.

3. Device according to one of claims 1 or 2, characterized in that the container (8) is fixable in at least one position, in particular steplessly.

4. Device according to claim 3, characterized in that the container (8) is fixable by means of a lever (13), a switch (13) or another manipulation means (13), preferably that the container (8) is fixable by frictional force.

5. Device according to one of claims 1 to 4, characterized in that the container (8) can be fastened to and unfastened from the connecting element (10) in a non-destructive way, preferably by a Bayonet connector.

6. Device according to one of claims 1 to 5, characterized in that the device, in particular the connecting element (10), comprises an information obtaining element (14) configured to obtain an information, particularly electronically and / or mechanically, wherein said information is carried by the device, in particular by the attached container (8), wherein preferably the obtained information is at least partially referring to the characteristics of the container (8) and / or the content thereof.

7. Device according to one of claims 5 or 6, characterized in that the connecting element (10) comprises a means (15) for removing at least a part of a sealing of the container, such that a sealing of the opening (9) of the container (8) is partly, particularly entirely, removed upon the first attachment of the container (8).

8. Device according to one of claims 1 to 7, characterized in that the container (8) comprises an air inlet (16) to allow an air flow into the container (8) during use.

9. Device according to one of claims 1 to 8, characterized in that the device (1) comprises a mass flow control means (17) to control the mass flow of abrasive material (3) from the container (8) to the impeller (2) via the inlet channel (5), wherein in particular the mass flow is controlled by an adjustment of the cross-section of the inlet channel (5), wherein in particular the mass flow control means (17) comprises a rotary knob (18).

10. Device according to one of claims 1 to 9, characterized in that the impeller (2) comprises an impeller core (19) and at least one fin (20) for accelerating the abrasive material (3), wherein the at least one fin (20) is formed separately from the impeller core (19), wherein in particular the impeller core (19) and the at least one fin (20) are made of different materials.

11. Device according to one of claims 1 to 10, characterized in that the impeller (2) is fastened detachably within the impeller housing (4), wherein in particular the impeller housing (4) is openable for the assembly and disassembly of the impeller (2).

12. Device according to one of claims 1 to 11 , characterized in that the impeller (2) is mechanically connected to, and driven by, a power drive (21), particularly an electric engine, and that the power drive (21) is fed by an energy storage device (22), particularly an accumulator.

13. Device according to claim 12, characterized in that the energy storage device (22) is detachably mounted to the device (1).

14. Use of a device (1) according to one of claims 1 to 13 for applying an abrasive material (3) onto a surface (24), in particular for sand blasting, characterized in that the center of gravity of the abrasive material within the container is located above the inlet channel with respect to the earth’s center of gravity during use.

15. Method for applying an abrasive material, in particular sand blasting, with a device according to one of claims 1 to 13.

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