System for locking a battery pack attached to a power tool

Abstract

The invention relates to a system (10) for locking a battery pack (20) attached to a power tool, comprising at least one battery pack (20) and at least one battery pack receptacle (40) formed on a housing (16) of the power tool, wherein the system (10) is configured to lock the battery pack (20), which is inserted translationally into the battery pack receptacle (40) in a sliding motion, in its inserted position on the power tool, wherein the battery pack (20) has at least one movable locking element (52) attached to the battery pack (20), which is configured to be moved from a locked position to a released position by actuating an actuating element (54) attached to the battery pack (20), wherein the actuating element (54) is configured to be actuated in a direction transverse to the direction (E) of the insertion motion.According to a first aspect of the invention, the system (10) is configured for locking and unlocking the battery pack (20) on one side. According to a second aspect of the invention, the system (10) has at least one further actuating element which is configured on the housing of the power tool for unlocking the battery pack on the machine side.

Description

The invention relates to a system for locking a battery pack attached to a power tool, having the features of the preamble according to claim 1. It is known from the prior art to slide battery packs into a battery pack holder of a power tool and to lock them in the inserted position on the power tool. Common locking devices for securing cordless power tools, such as handheld drills, hammer drills, and the like, with a battery pack for their power supply, typically feature several latches or locking elements. Each latch is movably mounted within the power tool's housing against spring force and engages a corresponding detent in the battery pack when the battery pack is inserted into a guide on the power tool to connect it. To release the connection, the power tool housing is equipped with corresponding release mechanisms, usually in the form of a push button located near the guide. These are manually operated to disengage the latch from its detent. Another well-known alternative for locking devices, which enables so-called one-handed operation of the battery pack, involves integrating the latches and the springs acting on the latches, along with two release buttons for unlocking the battery pack, into the battery pack itself. This allows the power tool to be held with one hand while the other hand grasps the battery pack, disengages the two latches from the recesses in the power tool housing by pressing the release buttons with a finger or thumb, and then pulls the battery pack out of the power tool's guide. The publication EP 1 481 769 A1 describes an example of such a locking mechanism. Furthermore, such a locking mechanism is also disclosed in the publication DE 10 2020 125 435 A1. This document further describes a solution with a holding device for arrangement on a battery pack of a machine tool, in particular a hand-held machine tool, with at least one receptacle for holding a tool, accessory, or consumable for the machine tool. Some known solutions also provide for a single release button on the battery pack, which, when manually pressed by the user, allows the battery pack to be detached from the power tool housing. Such a solution is known, for example, from German patent applications DE 10 2022 213 707 A1 and DE 10 2023 201 148 A1. The publication DE 10 2022 213 707 A1 discloses a battery pack for connecting to a hand-held power tool along a connection direction, with at least one locking element that can be brought into a locking engagement with the hand-held power tool, and with at least one actuating element, in particular designed separately from the locking element, for actuating the locking element, which is mounted to be linearly movable along an actuating direction. German patent application DE 10 2023 201 148 A1 discloses an electrical device, in particular a hand-held power tool, with a housing and a battery pack interface to which a battery pack can be locked via a locking element associated with the battery pack. The housing also features an operating element for directly actuating the locking element of the battery pack to unlock it. In addition to the two aforementioned alternatives, a combination of the two mechanisms is also known from the prior art, in which locking elements in the form of movable latches attached to the power tool are provided, which engage in detent recesses of the battery pack when locked. Furthermore, release devices for manually disengaging the locking elements from the corresponding detent recesses, which are attached to the battery pack, are provided. Reference is made in this regard to publication DE 10 2004 043 821 A1. German patent application DE 10 2004 043 821 A1 defines handheld electric power tools as power tools. However, for the purposes of the present application, this definition should also include other power tools, such as lawnmowers, vacuum cleaners, and the like. For a particularly compact design and additional protection of the battery pack(s) connected to the power tool, it may also be advantageous to provide a receiving slot on the power tool housing into which the battery pack(s) can be fully or almost fully inserted. Both the known solution of one-handed operation, in which the two release buttons are arranged on opposite sides of the battery pack, and the solution known from publication DE 10 2004 043 821 A1, require that sufficient space be provided on opposite sides of the battery pack in the inserted state to allow the release buttons or release mechanisms to be reached with the finger. DE 10 2023 202 870 A1 represents further state of the art. Depending on the installation situation, this can lead to an otherwise unnecessary increase in installation space, such as when battery packs are fully or almost fully inserted into a battery compartment on the housing. In particular, when the power tool is designed as a vacuum cleaner, lawnmower, or similar device, the dimensions (lateral installation space) of a designated compartment for one or more battery packs are also determined by the requirement that the release buttons or release mechanisms on the installed battery pack(s) must be freely accessible from both sides in order to operate them. In contrast, it may be desirable to provide a space-saving solution that also allows for secure locking of the battery pack. The invention proposes a system with the features of claim 1. Accordingly, a system for locking a battery pack attached to a power tool is provided, comprising at least one battery pack and at least one battery pack receptacle formed on a housing of the power tool, wherein the system is configured to lock the battery pack, which is inserted translationally into the battery pack receptacle in a sliding motion, in its inserted position on the power tool. The battery pack further comprises at least one movable locking element attached to the battery pack, which is configured to be moved from a locked position to a released position by actuating an actuating element attached to the battery pack, wherein the actuating element is configured to be actuated in a direction transverse to the direction of the insertion motion. According to the invention, the direction of actuation can therefore be, for example, perpendicular to the insertion direction, as in the solutions known from the prior art, wherein the actuating element(s) can be arranged on opposite side surfaces of the battery pack. According to the invention, the system is designed for one-sided locking and unlocking of the battery pack. Thus, unlike in the prior art, a two-sided locking mechanism symmetrical with respect to the insertion direction is not provided, but rather a one-sided asymmetrical locking mechanism. The battery holder can have one or two guide rails in a known manner, which engage in one or two corresponding guide grooves with complementary cross-sections. The battery pack is inserted into the battery holder by inserting the guide rail(s) into the corresponding guide groove(s). The locking system serves to prevent the battery pack from unintentionally coming loose from its fully inserted position. Although redundant locking mechanisms can be provided by the known two-sided symmetrical locking mechanisms, it is possible to save the space required for the unlocking mechanism on one side by eliminating one of the locks. At the same time, practical experience has shown that a single-sided lock is sufficient for the required securing of the battery pack. The locking element of the system, which is mounted on the battery pack so that it is relatively movable, can be spring-loaded towards its locking position, for example by means of an elastic spring element. To move it into its unlocked position, it must therefore be moved against the elastic preload by means of the actuating element arranged on the battery pack. This can be achieved, for example, by a mechanism as described in EP 1 481 769 A1. The actuating elements can be operated independently of one another, and the locking elements can also be designed to move independently of one another. In a specific embodiment, the actuating elements can be operated in a translational direction of movement that is essentially perpendicular to the direction of the insertion movement. Furthermore, the translational directions of movement of the actuating elements can run parallel to an insertion plane of the battery pack. Furthermore, according to the invention, the battery pack has at least one first side surface and at least one second side surface opposite the first side surface, which extend substantially parallel to the direction of the insertion movement, wherein the actuating element for the at least one movable locking element is attached at least on the first side surface. In principle, it would be conceivable to provide a locking mechanism with a locking element and actuator on only one side of a battery pack to achieve one-sided locking. However, it is essential for users today to be able to connect a single battery pack to different power tools. Since the space savings achieved by one-sided locking only apply to solutions where the battery pack is inserted into the battery holder at least up to the level of the actuator(s), a solution is preferred in which the battery pack has a double-sided locking mechanism with locking elements and associated actuators on both the first and second sides of the battery pack.In this way, the same battery pack can also be used advantageously in such power tools where the operating elements are freely accessible in the inserted position of the battery pack and a double-sided locking mechanism is preferable to a single-sided locking mechanism. Furthermore, according to the invention, the battery pack receptacle has a locking structure on one side of the battery pack receptacle associated with the first side surface of the battery pack for locking and unlocking the battery pack on one side, which is able to interact positively with the at least one movable locking element in such a way that when the locking element is in its locking position, the battery pack is secured against a release movement opposite to the insertion movement, and that when the locking element is moved into its release position, the battery pack can be released from the battery pack receptacle in the release movement opposite to the insertion movement. For the use of a battery pack with locking mechanisms on both sides, the battery receptacle is provided that, for locking and unlocking the battery pack on one side of the battery receptacle associated with the second side surface of the battery pack, it has a support structure designed to enable a translational insertion and removal movement of the battery pack into and out of the battery receptacle, regardless of whether the battery pack has another locking element on the second side surface. The system structure is designed such that, in the event of an additional locking element on the second side surface of the battery pack, this element cannot be brought into positive engagement with the system structure, but at most comes into contact with it. The system structure can be designed such that the locking element, which in its locked position extends from a second side surface of the battery pack towards the system structure, is held in its engaged release position by contact with the system structure, or such that the locking element, which in its locked position extends from a second side surface of the battery pack towards the system structure, only comes into contact with the system structure in its disengaged locking position. Regardless of the design, in both cases the locking element does not achieve a positive fit with the system structure, particularly since the latter does not have a rear gripping structure for the locking element, so that the locking element, in its disengaged locking position, cannot fulfill a safety function against an extraction movement of the battery pack from the battery pack receptacle. According to an alternative or additional embodiment of the invention, the battery holder may have a mechanical and / or electrical interface module that can be adapted to the battery pack to be received. Many manufacturers today rely on development concepts that, through a high number of identical parts, enable the production of higher volumes and lower manufacturing costs. In particular, solutions can also be provided that can be adapted to different locking concepts of a battery pack on a power tool with only minor modifications. The battery compartment can be fully or partially integrated into the power tool housing. The mechanical and / or electrical interface for a battery pack can be adapted to the specific battery pack by using an interchangeable interface module. For example, the battery holder can have a mounting slot into which a first-type mechanical interface module can be inserted by the manufacturer, enabling locking and unlocking of the battery pack from both sides on the machine side. If the same power tool is to be equipped with battery packs that feature locking on the battery pack side—i.e., battery packs with locking and actuating elements integrated into the battery pack—a corresponding second-type mechanical interface module can be inserted by the manufacturer. If the battery packs differ only or also with regard to their electrical interface, appropriate adaptation can be achieved by using an interchangeable electrical / mechanical or purely electrical interface module. Furthermore, it may be provided that the system has at least one additional actuating element which is designed on the housing of the power tool for machine-side unlocking of the battery pack. In this solution, the locking mechanism on the battery pack can be actuated via an additional actuating element integrated into the power tool housing. This actuating element serves to release the positive locking mechanism formed by the locking element located on one side of the battery pack, which secures the inserted battery pack in the battery pack holder. For example, a battery pack (with a two-sided locking mechanism, as is already well known from the prior art) can be locked on both sides in the battery pack holder on the power tool after insertion and unlocked on one side via the battery-side actuating element (attached to the battery pack), while the second side can be unlocked via the machine-side actuating element. In this way, a space-saving solution with redundant locking on both sides of the battery pack can be provided. This solution can of course also be used in the case of a one-sided locking of the battery pack, where, to unlock a single positive-locking locking element of the battery pack, the actuating element of the battery pack is not directly actuated by a user, but rather the actuating element on the housing of the machine (machine-side actuating element). In this context, the term "housing" of the power tool is not limited to components that hold or enclose the components of the power tool, but can also include an attachment housing, a flange or the like for holding, for example, a battery pack that is provided for on the power tool. Furthermore, it may be provided that the battery pack receptacle has a locking structure which is able to interact positively with the at least one movable locking element of the battery pack in such a way that, when the locking element is in its locking position, the battery pack is secured against a release movement opposite to the insertion movement, wherein the locking structure of the battery pack receptacle is movably designed on the battery pack receptacle and is configured to be moved into an unlocked position and out of the positive interaction with the at least one movable locking element of the battery pack by actuating the further actuating element. In this conceivable solution, a positive locking mechanism between a locking element of the battery pack and a locking structure of the battery pack holder is achieved by movably mounting the locking structure on the battery pack holder and allowing it to be disengaged from the battery pack's locking element by manually actuating the additional (machine-side) actuating element. This allows the positive locking mechanism between the battery pack's locking element and the battery pack holder's locking structure to be released without having to actuate the battery pack's corresponding actuating element. Therefore, it is not necessary to provide access to the battery pack's actuating element through a free space between the side of the battery pack and, for example, the inner wall of a (shaft-shaped) battery pack holder.In this way, a space-saving implementation can be achieved. An alternative solution provides that the battery pack receptacle not only has a locking structure that is able to interact positively with the at least one movable locking element of the battery pack in such a way that, when the locking element is in its locking position, the battery pack is secured against a release movement opposite to the insertion movement, but also has a release structure that is movable relative to the battery pack receptacle, wherein the release structure is in contact with the at least one movable locking element in an insertion position of the battery pack and, when the further actuating element is actuated, is able to move it into its release position. In this solution, the machine-side actuating element not only actuates and thus moves a movable locking structure on the battery pack mount, but also actuates a release structure. This release structure is arranged within the battery pack mount in such a way that, when actuated, it is able to move the battery-side locking element into its release position, thereby disengaging the positive locking mechanism. As a further alternative, it is also conceivable that the additional actuating element could interact with the battery-side actuating element to cause the locking element of the battery pack to move into its unlocked position. In this way, actuation of the additional (machine-side) actuating element could indirectly actuate the battery-side actuating element. It should also be noted that terms such as "comprehensive," "exhibit," or "with" do not exclude other characteristics or steps. Furthermore, terms like "a" or "that," which indicate a singular set of steps or characteristics, do not exclude a plurality of characteristics or steps, and vice versa. Further features and advantages of the invention will become apparent from the following description of an exemplary embodiment of the invention and from the dependent claims. The invention is described in more detail below with reference to the accompanying figures. The figures show several features of the invention in combination with one another. Of course, a person skilled in the art can also consider these features separately and, if necessary, combine them into further meaningful sub-combinations without having to make an inventive step. The figures show schematically: Fig. 1 an isometric view of a system according to the invention for locking a battery pack attached to a power tool, comprising two battery packs and two battery pack receptacles arranged side by side; Fig. 2 an isometric view of the system according to the invention according to Fig. 1 in a view tilted by 90 degrees; Figs. 3a-c an isometric view of the system according to the invention according to Fig. 1 with a battery pack detached from it (Fig. 3a), the battery pack in an isometric view (Fig. 3b) and the system according to Fig. 1 without battery packs attached to it (Fig. 3c); and Figs. 4a-c an alternative installation situation of a system according to the invention for locking a battery pack attached to a power tool in a top view (comparable to the view of Fig. 2), a side view (Fig. 4b) and in a sectional view along section line AA of Fig. 4b. The figures show a variant of the invention according to the first aspect of the invention in a highly simplified representation. The system 10 according to the invention for locking a battery pack attached to a power tool comprises, in the embodiment shown in Figs. 1 to 3b, two battery packs 20 and two battery pack receptacles 40 arranged side by side. Figures 1 to 3b show two side walls 12, 14, each laterally delimiting a battery pack receptacle 40. These could, for example, be housing side walls of a housing 16 of the power tool. They could be side walls of a mounting compartment for the battery packs or other walls or flanges provided by the housing design that laterally delimit the installation space next to the battery pack receptacles 40. A larger gap S is provided between the two battery packs 20, which is intended to allow the user to reach the actuating elements 54 of the two battery packs 20 accessible through this gap S with their fingers. However, the actuating elements 54 of the two battery packs 20 facing the side walls 12, 14 are not accessible due to the installation space shown. Figure 2 shows that the battery pack mounts 40 have an interface module 42. This module can be used to modify the interface mechanically and / or electrically. The interface modules are selected by the manufacturer to enable the power tool to be used with a specific type of battery pack, for example, with a first interface module that can be used for mechanical and electrical connection with a battery pack that has a locking mechanism 50. Thus, the same housing 16 of a power tool can be manufactured for different markets or manufacturers, which has a positive effect on production volumes and manufacturing costs. In the embodiment shown in Fig. 3a, the interface module 42 comprises a receiving bay 44 (open upwards in Fig. 1 and Fig. 3a) with two lateral guide rails 46a, 46b (relative to an insertion direction E of the battery pack 20). Each of the guide rails 46a, 46b initially serves, in the usual manner, to engage a corresponding guide groove 26 on the battery pack 20, which opens forwards in the insertion direction E. In this way, a battery pack 20 is inserted translationally into the receiving bay 44 in the direction E and secured against dislodging movement transverse to the insertion direction E by the rear engagement of the guide rails 46a, 46b and the guide groove 26. The receiving bay 44, by means of its end stop 48, defines a fully inserted position of the battery pack 20 in the battery pack receptacle 40. From this position, the battery pack 20 can only be released by a translational release movement in the opposite direction to E. To secure the battery pack 20 against an unwanted release movement, it is locked in the fully inserted position in the battery pack receptacle 40 by means of the system 10 according to the invention. Each of the guide grooves 26 has an inner groove surface 28 which is assigned to the system according to the invention for locking a first or second side surface 28a, 28b of the battery pack 20. For a locking function, the battery pack 20 shown has a locking mechanism 50 on each of the two inner surfaces of the lateral guide grooves 26, comprising a locking element 52 which is movable relative to the inner surface 28 of the respective groove. In a locked position, this element projects from the inner surface 28 of the groove and forms a stop; in the unlocked position, the locking element 52 can be retracted so that it no longer projects significantly from the corresponding inner surface 28 of the groove. The locking element 52 can be pre-tensioned in the direction of the locking position by means of an elastic spring element (not shown) of the locking mechanism 50 in a known manner. To move the locking element 52 into its release position, a user can press the respective actuating element 54 of the locking mechanism 50 on the side of the battery pack 20, thereby pulling the locking element 52 inwards against the spring tension in a known manner until it is (almost) flush with the inner surface 28 of the associated guide groove 26. The battery pack receptacle 40 shown on the right in Fig. 3a (analogously on the left in Fig. 4c) can be seen to have a locking structure 60 on one side. In the inserted position of the battery pack 20, this structure is able to engage positively with the locking element 52 to provide the desired security against unwanted removal or loosening in the opposite direction E. When inserting the battery pack 20 in direction E into the battery pack receptacle 20, the user can manually press and hold the corresponding actuating element 54. Alternatively, the locking element 52 can also be ramped (with a leading edge) on its leading edge in the insertion direction E. In this way, during the insertion movement in direction E, the locking element 52 can also be automatically moved into its release position in contact with the locking structure 60. In the inserted position, the locking element 52 then snaps into its locking position due to the spring preload and engages the locking structure 60 in a positive-locking manner. Instead of a ramp (lead-in slope) on the front edge of the locking element 52 in the insertion direction E, a ramp (lead-in slope) can of course also be formed on the upper edge of the locking structure 60 in Fig. 3a, such that the locking element 52 adjacent to it can be automatically moved into its release position as the insertion increases. The battery pack receptacle 40 shown on the right in Fig. 3a further reveals that it has a contact structure 62 on the opposite side. In the inserted position of the battery pack 20, this contact structure cannot engage positively with the locking element 52 to provide the desired security against unwanted removal or release movement in the opposite direction E. Instead, in the illustrated embodiment, the associated locking element 52 is in its locked position and can only come into contact with the contact structure 62 laterally, with this contact structure fulfilling no (significant) securing function (see also Fig. 4c). As an alternative to the embodiment shown, the system structure could also be designed such that the locking element 52 is held in contact with it in its unlocked position and in a position between the locked and unlocked positions. In this case, an existing frictional force in the contact area of ​​the locking element 52 on the system structure 62 would provide a frictional connection (and thus partially fulfill the locking function), however, the user could release the battery pack again without actuating the associated actuating element, which is why, in this embodiment, at least no locking function would be fulfilled. Finally, as can be seen in Fig. 3c, the locking structures 60 of the adjacent battery receptacles 40 are each arranged on the side facing the gap S and the contact structures are each arranged on the side facing the housing side 12, 14. Because each of the battery pack receptacles 40 has a locking structure 60 only on one side, namely the side facing the gap S, while the support structure 62 prevents locking on the other side, a one-sided locking of each battery pack 20 in the corresponding battery pack receptacle is achieved. This can also be released one-sidedly by the user manually actuating the actuating element 54 on the side facing the gap S. Figures 4a to 4c show an alternative installation situation in which only one battery pack 20 is included. In this solution, the right actuating element 54 of the battery pack 20 is freely accessible, while the other actuating element 54 (left in Figures 4a and 4c), facing the housing wall 14, is not accessible through the housing wall 14. Here, too, a one-sided locking mechanism is achieved on the freely accessible side of the battery pack 20 (right in Figures 4a and 4c), while the left locking element 52, facing the housing wall 14, cannot form a locking positive connection due to the lack of a locking structure (instead, a contact structure 62 is provided).

Claims

System (10) for locking a battery pack (20) attached to a power tool, comprising at least one battery pack (20) and at least one battery pack receptacle (40) formed on a housing (16) of the power tool, wherein the system (10) is configured to lock the battery pack (20), which is inserted translationally into the battery pack receptacle (40) in a sliding motion, in its inserted position on the power tool, wherein the battery pack (20) has at least one movable locking element (52) attached to the battery pack (20), which is configured to be moved from a locked position to a released position by actuating an actuating element (54) attached to the battery pack (20), wherein the actuating element (54) is configured to be actuated in a direction transverse to the direction (E) of the insertion motion.wherein the battery pack (20) has at least one first side surface (28a) and at least one second side surface (28b) opposite the first side surface (28a), which extend substantially parallel to the direction (E) of the insertion movement, wherein the actuating element (54) for the at least one movable locking element (52) is provided at least on the first side surface (28a), characterized in that the system (10) is designed for one-sided locking and unlocking of the battery pack (20), that the battery pack receptacle (40) has a locking structure (60) on one side of the battery pack receptacle associated with the first side surface (28a) of the battery pack (20) for one-sided locking and unlocking of the battery pack (20), which is able to interact positively with the at least one movable locking element (52) such that when the locking element (52) is in its locking position,the battery pack is secured against a release movement opposite to the insertion movement, and that when the locking element (52) is moved into its release position, the battery pack (20) can be released from the battery pack receptacle (40) in a release movement opposite to the insertion movement, and that the battery receptacle (40) has a contact structure (62) on one side of the battery receptacle (40) associated with the second side surface (28b) of the battery pack (20) for one-sided locking and unlocking of the battery pack (20), which is designed to enable a translational insertion and release movement of the battery pack (20) into and out of the battery receptacle, regardless of whether the battery pack (20) has a further locking element (52) on the second side surface. System (10) according to claim 1, characterized in that the battery holder (40) has a mechanical and / or electrical interface module (42) adaptable to the battery pack to be received. System (10) according to claim 1 or 2, characterized in that the system (10) has at least one further actuating element which is formed on the housing (16) of the power tool for a machine-side unlocking of the battery pack (20). System (10) according to claim 3, characterized in that the battery pack receptacle (40) for machine-side unlocking of the battery pack (20) has a locking structure which is able to interact positively with the at least one movable locking element in such a way that when the locking element (52) is in its locking position, the battery pack (20) is secured against a release movement opposite to the insertion movement, and that the locking structure of the battery pack receptacle (40) is movably designed on the battery pack receptacle (40) and is configured to be moved into an unlocked position and out of the positive interaction with the at least one movable locking element (52) of the battery pack (20) by actuating the further actuating element. System according to claim 3, characterized in that the battery pack receptacle (40) for machine-side unlocking of the battery pack (20) has a locking structure which is able to interact positively with the at least one movable locking element (52) such that when the locking element (52) is in its locking position, the battery pack is secured against a release movement opposite to the insertion movement; and that the battery pack receptacle (40) further has a release structure which is movably formed on the battery pack receptacle (40) relative to the battery pack receptacle (40), wherein the release structure is in contact with the at least one movable locking element (52) in an insertion position of the battery pack (20) and is able to move the latter into its release position when the further actuating element is actuated.

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