Drive unit with electric motor that can be operated by battery packs from different manufacturers

Abstract

Various manufacturers of battery-powered tools each offer their own battery packs, which differ in their design and connections. In particular, the DC voltage connections of some known battery packs are reversed, while the voltage supplied is the same. The present invention provides for equipping a drive unit with an interchangeable adapter unit suitable for different battery packs from various manufacturers. This is achieved by a rotatable intermediate element that ensures the correct polarity of the battery pack is always transmitted to the electric motor, regardless of its orientation relative to the drive.

Description

[0001] The present invention relates to a drive unit with a drive housing in which an electric motor, in particular for operating a container pump, is accommodated, wherein the drive housing is associated with an adapter unit for the detachable accommodation of a battery pack, the adapter unit has electrically conductive contact elements for contacting mating contact elements of the battery pack and the contact elements are electrically connected to supply terminals of an electric motor accommodated in the drive housing.

[0002] It is common practice to equip drive units for operating container pumps with electric motors, which are then supplied with the necessary power via a power cable. However, it has also become increasingly common to equip these electric motors with battery packs, enabling wireless operation. Firstly, this eliminates the need for a cumbersome cable that could trip over or be an obstacle for the user. More importantly, it means the pump no longer needs to be located near a power outlet, allowing containers to be emptied in virtually any location using battery-powered pumps.

[0003] In this context, it has become common practice for many machine tools to operate with easily interchangeable battery packs. These are inserted into a suitable adapter unit, locked into place, and connected to a terminal that links the necessary contacts of the battery pack to the electric motor—at least the two DC poles. Due to the widespread availability of such battery packs for machine tools, they are now offered by numerous manufacturers and provide comparable voltages. However, these manufacturers are keen to encourage their customers to purchase only their own brand of machine tools.This works by having the manufacturer's own battery packs with external shapes and connectors that do not work with the adapter units of other manufacturers, either because the locking mechanisms are not compatible in their shape, because the size and shape of the battery packs differ, or because the connectors are reversed, meaning the positive terminal is sometimes on the left and sometimes on the right.

[0004] In this context, the following documents are known from the prior art: DE 11 2013 006 567 T5, DE 41 00 463 A1 and DE 10 2021 104 825 A1.

[0005] Against this background, the present invention aims to create a drive unit which has an electric motor and which can be operated using battery packs from different manufacturers by simply replacing an adapter unit.

[0006] This problem is solved by a drive unit according to the features of independent claim 1. Meaningful embodiments of such a drive unit can be found in the subsequent dependent claims.

[0007] The provision includes a drive unit with a drive housing in which an electric motor, in particular for operating a container pump, is accommodated, wherein the drive housing is assigned an adapter unit for the detachable accommodation of a battery pack, the adapter unit has electrically conductive contact elements for contacting mating contact elements of the battery pack and the contact elements are electrically connected to supply terminals of an electric motor accommodated in the drive housing.According to the invention, this is characterized in that the adapter unit is detachably connected to the drive housing and is connected by an intermediate element and has electrically connected contact plungers for contacting contact surfaces of the intermediate element that are insulated from each other and connected to the supply terminals of the electric motor via wire lines, wherein the intermediate element can be received in a first position and a second position rotated by 180° between the adapter unit and the drive housing such that when changing from the first position to the second position, the assignment of the contact plungers to the contact surfaces changes.

[0008] In this context, it should be noted that the adapter unit can be selected to fit any battery pack manufacturer. In other words, an adapter unit designed for one manufacturer's battery packs can be used. However, if the drive unit is to be adapted for battery packs from a different manufacturer, the adapter unit is replaced so that the other manufacturer's battery packs can be connected to the electric motor via this adapter unit. Selecting the appropriate adapter unit ensures that the locking mechanism and the overall shape are compatible with the desired battery pack. However, this does not necessarily guarantee correct polarity.

[0009] The invention provides that the intermediate element is brought into electrically conductive contact with the adapter unit, so that the contact elements of the adapter unit press against contact surfaces of the intermediate element via contact pins, thus establishing a connection. The intermediate element can be, in particular, plate- or disc-shaped and its contact surfaces are connected to the supply terminals of the electric motor. The contact surfaces of the intermediate element can, for example, be marked with the polarity, so that it is only necessary to rotate the intermediate element so that its polarity matches the corresponding marking on the adapter unit. In this way, incorrect connection of the battery pack and electric motor can be avoided, even when using different battery packs from different manufacturers.

[0010] In a first embodiment, the contact surfaces of the intermediate element can be designed as sheet metal inserts placed on the intermediate element. These inserts form angled, terminal plug-in elements that pass through openings in the intermediate element and are connected to the wire leads beyond these openings. This allows for simple contact between the contact pins of the adapter unit and these contact surfaces. The intermediate element seals the interior of the drive housing at the top and provides an interface for the adapter unit. Since the only requirement is to insert the bent sheet metal inserts into an otherwise pre-fabricated plastic part, manufacturing the intermediate element in this way is cost-effective and straightforward.The plug-in elements on the side facing the electric motor can easily be connected with connecting wires, especially when conventional forms of cable connections are used.

[0011] In a further embodiment, the contact surfaces can be recessed in the intermediate element, so that the surfaces of the contact surfaces and the intermediate element are flush. This prevents the contact pins from catching on the edges of the contact surfaces, especially when the adapter unit is placed on top of the drive housing and they rub against the intermediate plate.

[0012] Preferably, the adapter unit or intermediate element may further be provided with raised elements and the respective counterpart with recesses, wherein contact between contact pins and contact surfaces only occurs in a position where the raised elements engage in the recesses, and the raised elements and the recesses are positioned such that a polarity of the battery pack specified by the adapter unit is correctly transmitted from the intermediate element to the supply terminals of the electric motor. As the adapter unit approaches the intermediate element, the raised elements will contact the surface of the respective counterpart; that is, if the raised elements are arranged on the intermediate element, they will contact the surface of the adapter unit, and if they are arranged on the adapter unit, they will contact the surface of the intermediate element.Only when the raised elements and the recesses, which can be designed as cavities, through-holes, notches, or the like, interact is a functional connection between the adapter unit and the intermediate element established. The raised elements are arranged so that the polarity of the battery pack interacting with the selected adapter unit only matches the polarity specified by the electric motor's supply connections when the intermediate element is inserted in the correct position—either first or second—in its receptacle. Therefore, depending on the selected adapter unit, the intermediate element must be positioned in either the first or second position for the mechanical assembly of the adapter unit with the drive housing to be successful.

[0013] However, the use of raised elements and recesses is not the only option. Alternatively, and with some advantage, the adapter unit can be designed to have first raised elements and the intermediate element to have second raised elements. The first raised elements interact with corresponding second raised elements, with contact between contact pins and contact surfaces only occurring in a position where the first raised elements are adjacent to the second raised elements. The first and second raised elements are positioned such that the polarity of the battery pack, as specified by the adapter unit, is correctly transmitted from the intermediate element to the supply terminals of the electric motor.If the position of the intermediate element is incorrectly chosen, extension elements will meet here, so assembly is not possible if there is no correct assignment of the position of the intermediate element to the selected adapter unit.

[0014] Preferably, the drive housing may have a tubular connection area for linking to the adapter unit, wherein the tubular connection area interacts with the adapter unit via a screw thread. In such a case, it is ensured that the adapter unit is positioned directly above the drive housing and approaches it in a plane parallel to the surface when tightened.

[0015] Regarding the mounting of the intermediate element, essentially two options are provided for its behavior. Firstly, the drive housing can be designed to have a receptacle for the intermediate element, in which the intermediate element is mounted in a rotationally fixed manner. With a rotationally fixed mounting, its position, i.e., first or second position, must be pre-selected. The intermediate element can have features in its design, such as flattened areas or notches, that engage with corresponding counter-forms in the receptacle and prevent rotation of the intermediate element.

[0016] Alternatively, the drive housing can be designed with a circular receptacle for the intermediate element, and the intermediate element can be mounted in the receptacle without rotation. In this case, it is advantageous if the adapter unit, during rotation (e.g., when tightening), engages the intermediate element and its position is determined by this engagement. This prevents assembly errors, as the raised elements designed for engagement work together to ensure that the engagement is sufficient to align the polarity with the battery pack being used.

[0017] Specifically, the adapter unit can be designed with first raised elements and the intermediate element with second raised elements, the first raised elements interacting with the second raised elements via lateral flanks. Through mutual rotation, the flanks engage with each other, and the rotating part carries the stationary part along as soon as the flanks meet. The position of the flanks and the raised elements is chosen such that, at the moment of contact, the flanks are correctly polarized on the contact surfaces of the contact pins.

[0018] To enable the adapter unit to be fixed to the drive housing, the drive housing may be provided with screw receptacles that correspond to screw holes in the intermediate element and the adapter unit in an operating position of the adapter unit. Since the screws are ultimately driven at least partially through the adapter unit and the intermediate element into the drive housing, they are mutually locked in the achieved position, preventing any change without loosening the screws.

[0019] Finally, it can be provided that the contact pins of the adapter unit are spring-mounted against the contact surfaces of the intermediate element via compression springs. Even with slight inaccuracies, this ensures that the contact pins are pressed firmly against the contact surfaces, thus guaranteeing the reliable function of the drive at all times.

[0020] The invention described above will be explained in more detail below using an exemplary embodiment.

[0021] They show Fig. 1 a drive unit with an adapter unit and an intermediate element, as well as a battery pack in a perspective exploded view, Fig. 2 the intermediate element in two representations in top view from above and below, Fig. 3 the adapter unit in two views, top view from above and below, Fig. 4 the adapter unit mounted on the intermediate element in a frontal cross-sectional view, as well as Fig. 5 the drive unit with an adapter unit and an intermediate element, as well as a battery pack in perspective exploded views in different positions of the intermediate element.

[0022] Fig. Figure 1 shows an exploded view of a drive unit 1, illustrating various components and their arrangement. The drive unit 1 comprises a drive housing 2, an adapter unit 5, an intermediate element 11, and can be equipped with a battery pack 20, also shown in the drawing.

[0023] The drive housing 2 is equipped with a tubular connection area 3, which serves for connection to the adapter unit 5. The tubular connection area 3 has a screw thread that interacts with the adapter unit 5 to ensure a secure mechanical connection. The drive housing 2 also includes screw receptacles 4 that correspond to screw holes 10 of the adapter unit 5 and screw holes 17 of the intermediate element 11 to enable stable mounting in the operating position.

[0024] The adapter unit 5 is designed for the detachable mounting of the battery pack 20 and contains electrically conductive contact elements 6, which serve to connect to mating contact elements 21 of the battery pack 20. For such contact, the battery pack 20 is typically inserted into the adapter unit 5 via an open end face, shown here at the rear of the image, and locked into place. In the locked position, the mating contact elements 21 (not visible here), which may be pairs of spring elements pressing against each other, engage with the contact elements, forcing the spring elements apart and thus establishing electrical contact. The contact elements 6 are connected to contact pins 7 on the underside of the adapter unit 5, which are used to connect the contact surfaces 12 of the intermediate element 11. The contact pins 7 are resiliently mounted on compression springs 8 to ensure a reliable electrical connection.

[0025] The intermediate element 11 is arranged between the adapter unit 5 and the drive housing 2 and can be received in a receptacle 22 in a first position and a second position rotated by 180°. The intermediate element 11 has contact surfaces 12, which are designed as sheet metal inserts and form end-ended, angled plug-in elements 13 that engage in Fig. 2 and Fig. 4 can be seen. These plug-in elements 13 are passed through openings 14 in the intermediate element 11 and connected beyond the openings 14 to wire leads that lead to the supply terminals of the electric motor. The contact surfaces 12 are received in recesses of the intermediate element 11, so that the surfaces of the contact surfaces 12 and the intermediate element 11 are flush with each other.

[0026] The intermediate element 11 is mounted in the receptacle 22 in the connection area 3 of the drive housing 2 in a rotationally fixed manner, ensuring stable positioning and a reliable electrical connection. If a different adapter unit 5 is used, which is designed for a different battery pack 20, it may be necessary to reverse the polarity with respect to the electric motor. For this purpose, the intermediate element can be rotated in the receptacle 22 and inserted in the opposite direction, while the wiring to the supply terminals of the electric motor remains unchanged. This allows different battery packs from various manufacturers to be used with the same drive unit simply by attaching a different adapter unit 5 to the drive housing 2.

[0027] Fig. Figure 2 shows a detailed representation of the intermediate element 11, which is installed in the drive unit 1 according to Fig. 1 is used. The intermediate element 11 is shown in two views, the left view showing a top side facing the adapter unit 5 and the right view showing a rear side of the intermediate element 11 facing the electric motor. In the top view, the contact surfaces 12, which are designed as sheet metal inserts, are clearly visible. These contact surfaces 12 are placed on the intermediate element 11 and terminate in angled plug-in elements 13, which are guided through openings 14 in the intermediate element 11. The contact surfaces 12 are received in recesses of the intermediate element 11, so that the surfaces of the contact surfaces 12 and the intermediate element 11 are flush. This ensures uniform and reliable contact with the contact pins 7 of the adapter unit 5, even in the event of rotation. The second raised elements 15 are described in the description. Fig. 4 and Fig. 5 explained in more detail. They serve to ensure the correct positioning of the intermediate element 11 between the adapter unit 5 and the drive housing 2.

[0028] The lower view of the intermediate element 11 shows the angled plug-in elements 13, which are guided through the openings 14. These plug-in elements 13 are connected beyond the openings 14 by wire leads, which establish the electrical connection to the supply terminals of the electric motor.

[0029] The screw holes 17 are visible from both the front and rear views of the intermediate element 11. These holes 17 correspond to the screw receptacles 4 of the drive housing 2 and enable a firm and secure fastening of the intermediate element 11 in the receptacle 22 of the drive housing 2. The correct positioning and fastening of the intermediate element 11 is crucial for a reliable electrical connection and the safe operation of the drive unit.

[0030] Fig. Figure 3 shows the adapter unit 5 according to Fig. 1, which is designed for the detachable mounting of a battery pack 20, is shown first in a view from below, facing the intermediate element, and then in a view from above, facing the battery pack 20. The adapter unit 5 is equipped with electrically conductive contact elements 6, which serve to contact mating contact elements of the battery pack 20. On the opposite side, they are connected to contact prongs 7, which ultimately establish contact via the intermediate element 11 with the supply terminals of an electric motor housed in the drive housing 2. The adapter unit 5 has several screw holes 10, which can be used for fastening to a drive housing or an intermediate element.

[0031] Fig. Figure 4 illustrates the adapter unit 5 and the underlying intermediate element in a side view, showing the arrangement of the contact elements 6 and their connection to the contact prongs 7. The contact prongs 7 are resiliently mounted against the contact surfaces 12 of the intermediate element 11, with compression springs 8 being used to cushion the contact prongs 7. The contact surfaces 12 of the intermediate element 11 are designed as sheet metal inserts that are placed in recesses on the intermediate element 11. These sheet metal inserts form end-ended, angled plug-in elements 13, which are passed through openings 14 in the intermediate element 11 and connected to wire leads beyond the openings 14.

[0032] The adapter unit 5 is equipped with first riser elements 9, which interact with corresponding second riser elements 15 of the intermediate element 11. These riser elements 9 and 15 are positioned such that contact between the contact pins 7 and the contact surfaces 12 only occurs in a specific position. This ensures that the polarity of the battery pack 20 specified by the adapter unit 5 is correctly transmitted to the supply terminals of the electric motor.

[0033] The intermediate element 11 can be inserted between the adapter unit 5 and the drive housing in a first position and a second position rotated by 180°. When switching from the first to the second position, the assignment of the contact pins 7 to the contact surfaces 12 changes, allowing for flexible adjustment of the electrical connection. However, this is only possible if an adapter unit 5 is also used that has the first raised element 9 on the opposite side, because if the intermediate element 11 were rotated, its second raised elements 15 would collide with the first raised elements 9 of the adapter unit 5, making assembly impossible. This is also desirable, as the battery pack 20 for use with the adapter unit 5 has the polarity shown and not a reversed polarity.

[0034] The adapter unit 5 and the intermediate element 11 are therefore designed to ensure a secure and reliable electrical connection between a battery pack and an electric motor, while simultaneously allowing for easy assembly and disassembly. The use of compression springs 8 to support the contact pins 7 ensures a uniform contact force and thus a stable electrical connection.

[0035] Fig. Figure 5 shows a drive unit in a representation according to Fig. 5 with a battery pack, wherein from one representation to the next the intermediate element 11, the adapter unit 5 and the battery pack 20 are shown in different positions, wherein, in contrast to the previous figures, the intermediate element 11 is mounted in its receptacle 22 without rotation.

[0036] The movement sequence begins on the left side. Adapter unit 5 is placed onto intermediate element 11 and then rotated to the left. The illustration is chosen to maintain the distances between the components, but this is only for clarity. Naturally, the components, especially the respective riser elements 9 and 15, should engage with each other.

[0037] After the adapter unit 5 is placed onto the intermediate element 11, rotation begins. The flanks of the first raised elements 9 quickly collide with the flanks of the second raised elements 15 of the intermediate element 11, thus driving the intermediate element 11 along in its rotation. When the adapter unit 5 reaches the position shown on the far right, only a screw fastening is required to fix the adapter unit 5 to the drive housing 2 of the drive unit 1. The rotation of the intermediate element 11 ensures that the voltage transmission from the contact elements 6 of the adapter unit 5 always matches the polarity of the electric motor.

[0038] The above description thus describes a drive unit which has an electric motor and which can be operated using battery packs from different manufacturers by simply replacing an adapter unit. REFERENCE MARK LIST 1 drive unit 2 drive housings 3 Connection area 4 screw mount 5 adapter units 6 contact element 7 contact stamps 8 compression spring 9 first increase element 10 screw through 11 Intermediate element 12 Contact area 13 Plug-in element 14 Passage 15 second increase element 17 screw through 18 first position 19 second position 20 battery pack 21 Counter contact element 22nd recording

Claims

Drive unit with a drive housing (2) in which an electric motor, in particular for operating a container pump, is housed, wherein the drive housing (2) is associated with an adapter unit (5) for the detachable mounting of a battery pack (20), the adapter unit (5) has electrically conductive contact elements (6) for contacting mating contact elements (21) of the battery pack (20) and the contact elements (6) are electrically connected to supply terminals of an electric motor housed in the drive housing (2), characterized in that the adapter unit (5) is detachably connected to the drive housing (2) by means of an intermediate element (11) and has electrically connected contact plungers (7) with the contact elements (6) for the respective contacting of contact surfaces (12) of the intermediate element (11) that are insulated from each other and connected to the supply terminals of the electric motor via wire leads,wherein the intermediate element (11) can be received in a first position (18) and a second position (19) rotated by 180° between the adapter unit (5) and the drive housing (2) such that a specific contact plunger (7) in the first position (18) contacts a first of the contact surfaces (12), while the same contact plunger (7) in the second position (19) contacts a second contact surface (12) different from the first contact surface (12), thereby reversing the polarity of the voltage transmitted to the electric motor. Drive unit according to claim 1, characterized in that the contact surfaces (12) of the intermediate element (11) are designed as sheet metal inserts which are placed on the intermediate element (11) and form terminal, angled plug-in elements (13) which are passed through openings (14) of the intermediate element (11) and are connected to the wire lines beyond the openings (14). drive unit according to claim 2, characterized in that the contact surfaces (12) are received in recesses of the intermediate element (11), so that surfaces of contact surfaces (12) and intermediate element (11) merge flush into one another. Drive unit according to one of the preceding claims, characterized in that the adapter unit (5) or the intermediate element (11) has raised elements and the respective counterpart has recesses, wherein contact between contact plungers (7) and contact surfaces (12) only takes place in a position in which the raised elements engage in the recesses and the raised elements and the recesses are positioned such that a polarity of the battery pack (20) specified by the adapter unit (5) is correctly transmitted from the intermediate element (11) to the supply terminals of the electric motor. Drive unit according to one of claims 1 to 3, characterized in that the adapter unit (5) has first riser elements (9) and the intermediate element (11) has second riser elements (15), wherein the first riser elements (9) interact with corresponding second riser elements (15), wherein contact between contact plungers (7) and contact surfaces (12) only takes place in a position in which the first riser elements (9) are located next to the second riser elements (15), and the first riser elements (9) and the second riser elements (15) are positioned such that a polarity of the battery pack (20) specified by the adapter unit (5) is correctly transmitted from the intermediate element (11) to the supply terminals of the electric motor. Drive unit according to one of the preceding claims, characterized in that the drive housing (2) has a tubular connection area (3) for connection with the adapter unit (5), wherein the tubular connection area (3) interacts with the adapter unit (5) via a screw thread. Drive unit according to one of the preceding claims, characterized in that the drive housing (2) has a receptacle (22) for the intermediate element (11), wherein the intermediate element (11) is mounted in the receptacle (22) in a rotationally fixed manner. Drive unit according to one of claims 1 to 6, characterized in that the drive housing (2) has a circular receptacle (22) for the intermediate element (11) and the intermediate element (11) is mounted in the receptacle (22) in a rotationally free manner. Drive unit according to claim 8, characterized in that the adapter unit (5) has first raising elements (9) and the intermediate element (11) has second raising elements (15), wherein the first raising elements (9) interact with the second raising elements (15) by mutual rotation via lateral flanks, wherein the rotating part takes the stationary part with it as soon as the flanks meet and the position of the flanks and the raising elements (9, 15) is selected such that at the moment of the flanks meeting the contact plungers (7) are in correct polarity on the contact surfaces. Drive unit according to one of the preceding claims, characterized in that the drive housing (2) has screw receptacles (4) which correspond to screw passages (10, 17) of the intermediate element (11) and the adapter unit (5) in an operating position of the adapter unit (5). Drive unit according to one of the preceding claims, characterized in that the contact plungers (7) of the adapter unit (5) are resiliently mounted against the contact surfaces (12) of the intermediate element (11) via compression springs (8).

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