Hand blender with internal motor unit

Abstract

The present invention relates to a hand blender (1) with an internal drive unit (3) consisting of a housing (2) with a top air inlet (2a) and a bottom air outlet (2b), wherein the drive unit (3) comprises a dedicated bottom fan (3a) and a brushless motor (3b) partially surrounded by a separating bridge (3c) which is connected to the separating cover (3e) of the drive unit (3) by means of at least one spacer (3e) allowing air to circulate inside the housing (2) through the air chamber (2d), and above the drive unit (3) there is at least one air heat sink (4) attached to the support plate (5) of the electronic control board (6). [Fig. 1]

Description

Title of the invention: Hand blender with internal motor unit Scope of the invention

[0001] The present invention relates to a hand blender having an internal drive unit and a brushless motor of the type used for mixing and / or grinding food, with an arrangement of elements adapted for working with food. Prior art

[0002] Nowadays, and with reference to the state of the art, hand mixers with an internal motor unit, with or without a cable, used for mixing and / or grinding food are well known.

[0003] For applications of these hand blenders in sectors such as catering, where the quantity of food handled is considerably higher, more powerful hand blenders are required. Compared to the motor unit needed for domestic applications, the motor unit required for catering applications, which demands more power, increases in both size and weight, resulting in very bulky and heavy hand blenders. Over time, there has been a demand for increasingly powerful hand blenders to process larger volumes of food in less time, leading to a difficult relationship between the blender's weight and power for it to be considered a "hand blender."

[0004] Furthermore, in existing models, safety problems have been detected when the shredding element, generally in the form of sharp blades, remains in operation for a short period after the motor stop command, due to the inertia of the blades' rotation. In addition to degradation of the internal components due to the humid environment in which they operate, the control elements do not remain moisture-tight. Summary of the invention

[0005] In view of this state of affairs, the present invention relates to a hand blender having an internal motor unit comprising a housing with a top air inlet and a bottom air outlet in which the motor unit consists of a dedicated bottom fan and a brushless motor partially surrounded by a separation bridge which is connected to the separation cover of the motor unit by at least one spacer allowing the circulation of air inside the housing through the air chamber, and above the motor unit there is at least one air sink attached to the support plate of the electronic control board.

[0006] The use of a brushless motor in hand blenders, i.e., those that do not rely on a base to operate, allows for the generation of higher torque and a higher speed, as it is more powerful than a brushed motor, which considerably reduces the weight of the blender body. However, its use requires more complex, specific electronics for its control, because in addition to controlling the transmitted current as in a traditional brushed motor, it is necessary to control the polarity, which governs the direction of rotation of the shaft.This difference between a traditional motor and a brushless motor necessitates the addition of a dedicated electronic control board, separate from the electronic boards typically found in hand blenders, which are responsible for managing the blender's functions (transmitting commands to activate the blender's controls). This electronic control board allows not only a rapid, gradual stop but also an immediate motor stop by short-circuiting the stator phases and generating a braking force in the opposite direction of rotation. This eliminates the risk of the motor cutting out because the blending elements continue to move despite the stop command.The addition of another element inside the case, which must house all the elements in the smallest possible space to be manageable, and, moreover, the electronic boards being a very sensitive element to an increase in temperature and humidity, generates the need for a different distribution of the elements, which must take into account the gain in space (which induces the grouping of the elements) and the ventilation required (which requires air chambers between the elements), and which is all the greater as the motor is powerful and has a more complex control board for the brushless motor.

[0007] Consequently, in addition to the increased number of components, the brushless motor requires more ventilation (due to the increased power), and the increased number of electronic boards due to the addition of the electronic control board necessitates more cooling and protection against humidity. Proper cooling of the electronic board is ensured by positioning an air heat sink connected to the electronic control board and attached to the support plate located above the motor unit—that is, on the upper part when the hand mixer is in the working or upright position. A single dedicated lower fan draws air from the upper air intake and expels it through the lower air outlet.Thanks to the generation of an airflow contrary to the usual practice of lower air intake and upper outlet, it is possible to work on hot foods that expel steam by absorbing the cooler and less humid air from the upper intake and first cooling, and with less humidity, the element most sensitive to the The temperature of the electronic control board is maintained through the heat sink attached to the support plate on the motor unit. Air then circulates within the housing through the air chamber created by the geometry of the separating cover, thin spacers, and the separation bridge around the motor unit to cool the brushless motor. After passing through the dedicated lower fan, which modifies the airflow direction, the superheated air is expelled through the lower air outlet. This high-velocity expulsion of superheated air also creates a barrier around the lower air outlets, diverting the upward flow of steam away from the food. This creates a less humid space that extends to the upper air intake, located higher up (in the vertical or working position), thus allowing the intake of cooler, less humid air from the upper air intake.This arrangement of elements also allows the electronic components to be placed in the area furthest from heat and humidity and closer to the control elements, which improves cooling, protection against the effects of humidity, and facilitates the connection of the electronic elements.

[0008] An additional advantage is that the brushless motor is firmly anchored by the separation bridge, separation cover, and spacer assembly, which, thanks to its configuration, positions it in the center of the housing without obstructing ventilation. This is achieved through the cantilevered configuration of the separation bridge, which surrounds the dedicated lower fan and partially the motor. The typical movements of hand mixers (horizontal position at rest, vertical position during operation with possible tilting relative to the shaft) require that the components be securely anchored to withstand the work cycle without shifting.Furthermore, its central position in the housing allows, on the one hand, for the center of gravity of the motor unit (the heaviest component of the blender) to be perfectly positioned both horizontally and vertically, and on the other hand, for the creation of an air chamber inside the blender and around the brushless motor, which allows for proper air circulation that produces heat dissipation.

[0009] The solid anchoring of the motor unit, regardless of the position of the hand mixer, and the creation of the air chamber are ensured by the fact that the separation bridge is equipped with at least one transverse support rib, a perimeter support and flow orifices which allow it to be cantilevered from the inner walls of the housing.

[0010] The position of the support ribs against the housing facilitates the transmission of the motor unit's weight when the hand mixer is positioned horizontally (at rest), thus avoiding stress on the anchors. At the same time, the perimeter support helps distribute the motor unit's weight when angular movements are performed during operation. Furthermore, since these support elements are not fixed to the housing, they can be detached for maintenance, repair or replacement of parts.

[0011] Thanks to the interlaced configuration of the support ribs and the creation of flow ports, an uninterrupted air chamber is created, allowing the brushless motor and the electronic control board to be cooled by a single airflow. This continuous air chamber surrounds the brushless motor, through which the ventilation air flows in a unified manner, thus efficiently cooling the brushless motor and enabling the movement of the dedicated lower fan by generating the largest possible air chamber volume around it. This increased air chamber volume also allows for a greater ventilation airflow, resulting in optimal cooling of the electronic control board located above the motor unit.

[0012] The separating bridge has at least one perimeter seat in which the mounting hole is located, which can incorporate the end of the spacer. It is thus possible to incorporate spacers of different sizes, which allows this configuration to be applied to different modules of varying lengths, while always ensuring the same location of the brushless motor and the dedicated lower fan in the center of gravity of the hand blender body.

[0013] Thanks to this configuration of the elements, secure support for the drive unit, which bears the weight of the brushless motor, and the correct working position are guaranteed. The separating cover is connected by means of the spacer element, which absorbs the forces due to the shift in the center of gravity of the brushless motor caused by tilting the hand mixer during operation. Furthermore, by centering the support and the attachment on a single element, the volume of the air chamber is maximized, allowing for greater ventilation and therefore better cooling.

[0014] Furthermore, the motor unit's separating cover has at least one fin and ventilation openings that allow it to cantilever out from the inner walls of the housing. Thanks to the cantilevered support of the fin, the weight of the motor unit can be transferred when the hand mixer is positioned horizontally (at rest), and the motor unit is stabilized when angular movements are made during operation. The configuration of the fin and ventilation openings allows for smooth and efficient circulation of the ventilation airflow all around the brushless motor, thus ensuring optimal motor cooling.

[0015] The fin has an insertion hole that can accommodate the end of the spacer. This modular configuration of the separation bridge and the separation cover allows, thanks to the fact that the spacer element can be supplied in different sizes, the same configuration to be adapted to different sizes of brushless motors and hand blenders and use the same elements for different motors, which allows for the standardization of components for a range of hand blenders of different power (different motor sizes).

[0016] In addition, the support plate has a heat sink fixed on its ventilated surface and an electronic control board on its sealed surface, as well as a perimeter protrusion which can be fixed on the inner walls of the housing.

[0017] Thanks to this configuration, the support plate fits securely into the inner walls of the housing, keeping its components firmly fixed regardless of the hand blender's position, insulated, and sealed. Furthermore, by fitting into the inner walls of the housing, the sealed surface containing the most sensitive electronic components of the electronic control board is isolated from moisture from food vapor. In this way, the ventilated surface is positioned optimally, near the upper air intake, when the heat sink is attached to it. This ensures complete contact between the surface and the cooler, less humid ventilation air (from outside), effectively cooling the electronic board to which it is connected internally.It is also planned that the electronic components housed in the ventilated surface will be coated with a protective resin layer for better protection.

[0018] An additional advantage is that the perimeter projection, due to its increased height, allows a layer of resin to be added up to the edge of the perimeter projection (generally, a small amount is applied in the form of varnish), which makes it possible to completely cover the most moisture-sensitive elements and to protect them further from the humid atmosphere of the working environment. Figures

[0019] In order to better understand the nature of the invention, the accompanying drawings show an industrial embodiment which is merely illustrative and not limiting.

[0020] [Fig.1]

[0021] Fig. 1 shows a longitudinal section along the shaft of the hand mixer (1) showing the arrangement of the components which, from top to bottom, in the vertical or working position, are the electronic control board (6) located at the top with the other electronic components located on the support plate (5) mounted in the housing (2) from which hangs the heat sink (4) facing the upper air inlets (2a) in an air chamber (2d). Below, in descending order, can be seen the separating cover (3e), the spacers (3d), the brushless motor (3b), the separating bridge (3c) and the dedicated lower fan (3a) which make up the motor unit (3), the fan lower dedicated (3a) facing the lower air outlets (2b) and which is crossed by the shaft (7) which extends along its lower part.

[0022] [Fig.2]

[0023] Fig. 2 shows a longitudinal section along the perspective shaft of the hand mixer (1) showing the housing (2) and the inner wall of the housing (2d) and the arrangement of the elements which, from top to bottom, in the vertical or working position, would be the electronic control board (6) located at the top with the other electronic components located on the support plate (5) from which the heat sink (4) is suspended in an air chamber (2d) above the drive unit (3) consisting of the separation cover (3e), the spacers (3d), the brushless motor (3b), the separation bridge (3c) and the dedicated lower fan (3a).

[0024] [Fig.3]

[0025] Fig. 3 presents an exploded view of the hand mixer (1) showing the housing (2) divided into two parts, of which can be seen the inner wall of the housing (2d), the support plate (5) with the electronic control board (6) on its sealed surface (5b), the perimeter projection (5c), the heat sink (4) on its ventilated surface (5a) and the motor unit (3).

[0026] [Fig.4]

[0027] Fig. 4 shows an exploded view of the drive unit (3), showing the separation cover (3e) with the fin (3el) in which the insertion orifice (3el.1) is located, the brushless motor (3b) through which the shaft (7) passes, the spacers (3d), the dedicated lower fan (3a) and the separation bridge (3c) consisting of the support rib (3c1), the perimeter seat (3c2) in which the mounting orifice (3c2.1) can be seen, the perimeter support (3c3) and the flow orifices (3c4).

[0028] [Fig.5]

[0029] Fig. 5 shows a zenithal view of the separation cover (3e) with the fins (3e1) and the ventilation ports (3e2). Detailed description

[0030] With reference to the drawings and references listed above, a preferred embodiment of the object of the invention is illustrated in the accompanying drawings. It is a hand blender (1) with an internal drive unit (3) comprising a housing (2) with a top air inlet (2a) and a bottom air outlet (2b) in which the drive unit (3) consists of a dedicated bottom fan (3a) and a brushless motor (3b) partially surrounded by a separating bridge (3c) which is connected to the separating cover (3e) of the drive unit (3) by at least one spacer (3d) allowing air to flow inside the housing (2) through the air chamber (2d), and above the drive unit (3), there is at least one air heat sink (4) attached to the support plate (5) of the electronic control board (6).

[0031] The use of a brushless motor (3b) in the hand blender (1) allows for the incorporation of a more powerful motor (which generates more torque and allows operation at higher speeds), thus significantly reducing the weight of the hand blender body (1). The brushless motor (3b) requires the addition of a complex electronic control board (6) for motor control, located next to the blender controls, as can be seen in [Fig. 2]. This electronic control board (6) enables the immediate stopping of the motor by generating a force opposite to the direction of rotation at the moment of stopping, so that the residual inertial movement of the shaft is counteracted, thereby eliminating the risk of breakage due to the grinding elements remaining in motion despite the stop command.Adding the electronic control board (6), which is very sensitive to temperature rise and humidity, inside the housing (2) requires repositioning the components without increasing the internal volume of the housing (2) and providing adequate ventilation for all components and protection against humidity for the most sensitive electronic components.

[0032] On the one hand, the brushless motor (3b) requires more ventilation for adequate cooling (due to the increased power it generates) and, on the other hand, the increased size and complexity of the electronic board, with the addition of the electronic control board (6), necessitate more cooling and protection against humidity. To ensure adequate cooling of the electronic control board (6), it is placed on the sealed surface of the support plate (5), which is fixed to the ventilated surface (5a) of the support plate (5), and a heat sink (4) is fixed to the electronic control board (6). The support plate (5) is positioned above the motor unit (3), i.e., at the top when the hand mixer is in the working position or in the vertical position. As shown in [Fig.l], at the opposite end, a single dedicated lower fan (3a) is installed, which draws air from the upper air inlet (2a) and expels it through the lower air outlet (2b).In this way, it is also possible to work on hot foods that expel steam and by absorbing air from the upper inlet (2a) which is cooler and less humid, and first cooling, with less humidity, the most temperature-sensitive element which would be the electronic control board (6) through the air heat sink (4) fixed to the support plate (5) placed on the motor unit (3), continuing the circulation of air inside the case (2) through the air chamber (2d) generated by the geometry of the separation cover (3e), the spacers (3d) and the separation bridge (3c) around the motor unit (3) to cool the brushless motor (3b) and, after passing through the dedicated lower fan (3a), which changes the direction of the airflow, expel the superheated air through the lower air outlet (2b). The high-speed expulsion of superheated air also creates a barrier around the lower air outlets (2b) that diverts the upward flow of food vapor. This arrangement of elements also allows the electronic components to be placed in the area furthest from heat and humidity, separated from the other elements by the support plate (5) and closer to the control elements.

[0033] The typical movements of hand blenders (1) (horizontal position at rest, vertical position during operation with possible tilting relative to the shaft) require that the components be securely anchored to withstand the work cycle without shifting. To this end, the brushless motor (3b), which is the heaviest component, is securely anchored and positioned by means of the separation bridge assembly (3c), the separation cover (3e), and the spacer (3d). Thanks to the geometry of the components, it is positioned in the center of the housing (2), but without obstructing ventilation, thanks to the cantilevered configuration of the separation bridge (3c), which surrounds the dedicated lower fan (3a) and partially the brushless motor (3b).

[0034] The solid anchoring of the drive unit (3) regardless of the position of the hand mixer (1) and the creation of a continuous air chamber (2d) are ensured by the fact that the separating bridge (3c) is intersected by at least one transverse support rib (3c 1) and a perimeter support (3c2) which allow its cantilevered support on the inner walls of the housing, and by the flow ports (3c4), which allow the volume of the air space (2d) to be increased.

[0035] The position of the support ribs (3c1) against the inner wall of the housing (2d) allows the weight of the motor unit (3) to be transmitted when the hand mixer (1) is positioned horizontally (at rest), preventing stress in the anchors. This avoids the development of play that would produce vibrations and thus extends the service life of the hand mixer (1). In turn, the perimeter support (3c3) distributes the weight of the motor unit (3) when angular movements are performed during operation. Furthermore, since these are support elements, they are not attached to the housing (2), which can be detached for maintenance, repair, or replacement of parts.

[0036] Thanks to the interlaced configuration of the support ribs (3c1) and the creation of flow ports (3c4), a continuous and barrier-free air chamber (2d) is created around the brushless motor (3b), through which the ventilation air circulates in a unified manner and can, thanks to a single airflow, efficiently cool the electronic control board (6) and the brushless motor (3b). This increase in the volume of the air chamber (2d) also allows for a greater ventilation airflow, improving the cooling of the electronic control board (6) located on the motor unit (3) (improving heat dissipation by the heat sink (4) connected to the electronic control board (6)).

[0037] The separating bridge (3c) has at least one perimeter seat (3c2) in which the mounting hole (3c2.1) is located, capable of incorporating one end of the spacer (3d). This allows spacers (3d) of different sizes to be incorporated, making it possible to apply the same configuration to different modules of varying lengths, while always ensuring the same location for the brushless motor (3b).

[0038] The brushless motor (3b) is placed on the separating bridge (3c) and partially surrounded by it, which ensures secure support for the brushless motor (3b) and a correct working position. The separating bridge (3c) is connected to the separating cover (3e) by means of four spacer elements (3d), preferably containing the brushless motor (3b) and forming the drive unit (3), thus capable of absorbing and compensating for the forces due to the displacement of the center of gravity of the brushless motor (3b).Furthermore, by centering the support and fixing on a single element (the separation bridge element (3c)), the volume of the air chamber is maximized, which allows for greater ventilation flow and therefore better cooling by being able to separate the drive unit (3) comprising the separation bridge (3c), the separation cover (3e), the spacers (3d), the brushless motor (3b) and the dedicated bottom fan (3a) from the inner walls of the case (2c).

[0039] This independence of the inner walls of the housing (2c) from the separating cover (3e) of the drive unit (3) is possible because the separating cover (3e) has at least one fin (3e 1) which allows it to cantilever over the inner walls of the housing (2c). Thanks to the cantilevered support of the fin (3e 1), this allows for the balanced transmission of the weight of the drive unit (3) when the hand mixer (1) is positioned horizontally (at rest) and the stabilization of the drive unit (3) when angular movements are made during operation. Furthermore, as can be seen in [Fig.5], the separation cover (3e) has several ventilation openings (3e2) which, together with the separation of the inner walls of the housing (2c) generated by the fins (3e1), allow the smooth and efficient circulation of ventilation air around the brushless motor (3b), and thus optimal cooling of the motor, as well as its passage to the lower part of the inside of the housing after cooling of the support plate (5).

[0040] Individually, each fin (3e 1) has an insertion hole (3e 1.1) that can accommodate the end of a spacer (3d) which connects the separating cover (3e) to the separating bridge (3c). This modular configuration of the separating bridge (3c) and the separating cover (3e), thanks to the fact that the spacer element (3d) can be supplied in different sizes, allows the configuration to be adapted to the different sizes of brushless motors (3b) required for different hand blenders (1). This adaptability makes it possible to standardize the components for a range of hand blenders. of different powers (different motor sizes) using the same separation bridge elements (3c) and the same separation cover (3e) for different brushless motors (3b) with modification of the spacer element (3d) adapted to the distance of the brushless motor (3b) which integrates the motor unit (3).

[0041] Fig. 3 shows how the support plate (5), located on the drive unit (3) in the vertical or working position, has on its ventilated surface (5a) a heat sink (4) fixed to the electronic control board (6) located on its sealed surface (5b) and has a perimeter projection (5c) which can be mounted on the inner walls of the housing (2c).

[0042] The support plate (5) snaps securely into the inner walls of the housing (2c) around its entire perimeter, holding the components it contains firmly in place regardless of the position of the hand blender (1). Furthermore, by fitting into the inner walls of the housing (2), the sealed surface (5b) on which the electronic control board (6) (containing electronic components sensitive to moisture from food vapors) is located is isolated from the ventilated surface (5a), so that moisture does not reach the sealed surface (5b). In addition, the ventilated surface (5a), on which the heat sink (4) is positioned, is located in the most suitable position for heat dissipation, near the upper air inlet (2a).By placing the heat sink (4) attached to the ventilated surface (5a), contact is ensured across the entire surface of the heat sink (4) with the cooler, less humid ventilation air (that received from outside through the upper air intake (2a)), effectively cooling the electronic control board (6) to which it is connected internally. Furthermore, this ventilated surface, as well as the components housed on it, will be protected by a layer of resin for added safety.

[0043] The perimeter projection (5c), due to its increased height, allows the addition of a layer of resin up to the edge of the perimeter projection (generally a small amount is applied in the form of varnish), which allows even the most moisture-sensitive elements of the electronic control board (6) located on the sealed surface (5b) of the support plate (5) to be completely covered and protected from the humid atmosphere of the working environment.

[0044] The variations in materials, shape, size and arrangement of the constituent elements, described in a non-limiting manner, do not alter the essential character of the present invention and are sufficient to be reproduced by a person skilled in the art.

[0045] Nomenclature

[0046] The following references are shown in Figures 1 to 5:

[0047] L- Hand mixer.

[0048] 2.- Housing.

[0049] 2a- Upper air inlet

[0050] 2b- Lower air outlet

[0051] 2c- Inner wall of the housing

[0052] 2d- Inner tube

[0053] 3.- Motor unit.

[0054] 3 a- Dedicated lower fan

[0055] 3b- Brushless type brushless motor

[0056] 3c- Separation Bridge

[0057] 3c 1- Supporting rib

[0058] 3c2- Perimeter seat

[0059] 3c2.1 mounting hole

[0060] 3c3- Perimeter support

[0061] 3c4- Drain orifice

[0062] 3d- Spacer

[0063] 3e- Separation cover

[0064] 3rd 1- Fin

[0065] 3el. 1.1 insertion port

[0066] 3e2- Ventilation openings

[0067] 4.- Heat sink

[0068] 5.- Support plate:

[0069] 5a- Ventilated surface

[0070] 5b- Waterproof surface

[0071] 5c-Perimeter projection

[0072] 6.- Electronic control board

[0073] 7.- Tree

Claims

Demands

1. Hand blender (1) with an internal drive unit (3) consisting of a housing (2) with a top air inlet (2a) and a bottom air outlet (2b), characterized in that the drive unit (3) consists of a dedicated bottom fan (3a) and a brushless motor (3b) partially surrounded by a separation bridge (3c) which is connected to the separation cover (3e) of the drive unit (3) by means of at least one spacer (3e) allowing air to circulate inside the housing (2) through the air chamber (2d), and above the drive unit (3) there is at least one air dissipator (4) attached to the support plate (5) of the electronic control board (6).

2. Hand mixer (1) according to claim 1, characterized in that the separating bridge (3c) has flow orifices (3c4) intersected by at least one transverse support rib (3c1) and a perimeter support (3c3) capable of being supported on the inner walls of the housing (2d).

3. Hand mixer (1) according to the preceding claims, characterized in that the separating bridge (3c) has at least one perimeter seat (3c2) in which is located the recessed orifice (3c2.1), capable of incorporating one end of the spacer (3d).

4. Hand blender (1) according to the preceding claims, characterized in that the separating cover (3e) of the motor unit (3) has ventilation openings (3e2) and at least one fin (3e1) which allow it to cantilever over the inner walls of the housing (2c).

5. Hand mixer (1) according to the preceding claims, characterized in that the blade (3el) has an insertion orifice (3el.l) capable of housing one end of the spacer (3d).

6. Hand mixer (1) according to the preceding claims, characterized in that the support plate (5) has on its ventilated surface (5a) a fixed heat sink (4) and on its sealed surface (5b) an electronic control board (6) and is bordered by a perimeter projection (5c) capable of adapting to the inner walls of the housing (2c).

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