Device for Mounting Battery Cells of a Battery Pack

Abstract

A device which holds rechargeable batteries cells in a battery pack, in particular for a handheld electric tool, with a first holding part and a second holding part which together with the interposed battery cells can be joined and affixed to one another. The invention includes protrusions of the first holding part extending in the assembly direction which are formed with a yieldable outer periphery, so that they can be inserted into and locked in openings formed in the second holding part.

Description

BACKGROUND OF THE INVENTION

The invention is directed to a device for mounting battery cells of a battery pack, in particular for a handheld electric tool, with a first holding part and a second holding part which can be joined and locked onto one another by interposing the rechargeable battery cells.

Such devices are generally known. The first holding part is connected to and locked onto the second holding part by a clip connection. However, with the clip connection, the first holding part and the second holding part can only be secured with respect to one another with a certain spacing, making such devices suitable only for battery cells of a certain geometry, in particular battery cells having a certain height.

In another device, the first holding part is connected with the second holding part by a screw connection which, however, is time-consuming.

BRIEF SUMMARY OF THE INVENTION

It is an object of the invention to provide a device which can be more easily assembled.

This object is attained by the invention with a device wherein protrusions of the first holding part extending in the assembly direction are formed with a yieldable outer periphery, so that they can be inserted into openings of the second holding part and locked therein.

Although the openings have an inside contour which is substantially complementary to the outer contour of the protrusions, the openings are slightly tapered towards the outer contour, so that the protrusions of the first holding part can be lockingly secured in the openings.

Through latching with the protrusions, battery cells of different height can be gripped with the device of the invention. The assembly process is also simplified substantially. A yieldable outside diameter is defined as a diameter which can change, in particular be tapered, perpendicular to the assembly direction,.

In an advantageous embodiment of the device of the invention, the protrusions are formed as pins. The protrusions extend as columns in the assembly direction from the first holding part towards the second holding part. Advantageously, the device is compact and open perpendicular to the assembly direction.

In one exemplary embodiment of the invention, the outer periphery of the protrusions has a slightly tapered, in particular conical contour. The protrusions can then be easily inserted into the openings without requiring exactly alignment.

The tapered outer periphery of the protrusions is preferably inclined by an angle of 0.5° to 3.0° with respect to the assembly direction.

In an advantageous exemplary embodiment of the invention, the protrusions have at least one slot. The at least one slot can extend in the assembly direction and can be contiguous throughout the protrusion, i.e., the slot can divide the protrusion into segments. Alternatively, several slots in form of a cross slot arrangement may be provided. Preferably, the protrusion has a slot that extends in the assembly direction and ends at the free end of the protrusion, as viewed in the assembly direction. The segments of the protrusion formed in this manner can the move towards one another or be pressed against each other. This arrangement realizes a yieldable outer periphery.

In a preferred exemplary embodiment of the device, the first holding part and the protrusions are formed as a single piece or from separate individual components. The protrusions and the first holding part can therefore be produced in a single common injection molding process or can be assembled in a later processing step. Advantageously, the first holding part and the second holding part can be used for different battery cells of significantly different height, wherein the protrusions need only match the height of the actually employed batteries.

In another modification of the aforedescribed device, the first and/or the second holding part include spacer elements which each separate two adjacent battery cells. The spacer elements can be formed as a single piece with the first or the second holding part or can be attached as separate components to the first or second holding part. Advantageously, by separating the adjacent battery cells, the battery cells may be prevented from contacting each other so that even battery cells which are not electrically insulated can be used.

According to yet another exemplary embodiment of the device, the openings of the second holding part have a tapered interior contour and, more particularly, are conically shaped.

According to an advantageous embodiment of the device of the invention, the first holding part and/or the second holding part have frame means, which secure the battery cells and prevent them from moving perpendicular to the assembly direction. For example, the frame means may be formed as one piece with the holding parts; alternatively, the frame means may be separate individual components, which are made of one or several separate individual components and are inserted into the holding parts. The frame means are formed with a geometry that is complementary to the geometry of the battery cell, so that the battery cells are positively locked by the frame means. This prevents the battery cells from wobbling in the holding parts.

In a particularly preferred exemplary embodiment of the device, the frame means are formed as openings or recesses in the first and/or in the second holding part. The frame means is hence an integral component of the first and/or second holding part, resulting in a very compact device with a small parts count.

In a modified embodiment of the aforedescribed invention, the frame means have in the assembly direction an opening extending through the first and/or the second holding part, making a battery cell accessible from the outside. In this way, the battery cells can be contacted or welded to each other, for example by using contact sheets.

Moreover, in another exemplary embodiment of the device, the first and/or the second holding part, including the protrusions, is preferably formed as a plastic injection molded part.

Advantageously, the first and/or the second holding part have a limit stop in the assembly direction. By providing a limit stop, the device can be adapted to battery cells of a defined size, wherein the assembled device has a predefined height.

In yet another exemplary embodiment of the device, the limit stop is formed on the protrusions as a shoulder perpendicular to the assembly direction.

Additional features, details and advantages of the invention are recited in the dependent claims and the drawings and in the following description of a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

The drawing shows in:

FIG. 1 a perspective view of a first holding part of a device according to the invention;

FIG. 2 a perspective view of a second holding part of the device according to the invention; and

FIG. 3 a perspective view of the assembled device according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

The figures illustrate a device 2 for mounting rechargeable battery cells 4 in a battery pack, wherein a first holding part 6 can be connected with a second holding part 8. The first holding part 6 has protrusions which extend in an assembly direction 10 and can be inserted into openings 14 of the second holding part 8, where they can be locked in position.

FIG. 1 shows the first holding part 6 of the device 2 with the protrusions 12 being formed with the first holding part 6 as a single part. The protrusions 12 have a conical outer contour and a slot 16 with an open edge towards the free end. With the open slot 16, the respective protrusion 12 can be pressed together by moving the sections created by the slot 16 towards one another. This produces the yieldable outer periphery. In addition, the protrusions 12 have each a limit stop 20 implemented as a shoulder 18.

In addition to the protrusions 12, spacer elements 22 separating the installed battery cells 4 are arranged on the first holding part 6. The spacer elements 22, like the protrusions 12, have shoulders 18 which can operate as a limit stop.

Spacer elements 22 and protrusions 12 are arranged between frame means 24 of the first mounting part; these space the battery cells 4, which are not illustrated in FIG. 1, apart from one another. The frame means 24 are hereby formed by cavities 26 extending in the assembly direction 10. The frame means 24 are used to secure the battery cells 4 perpendicular to the assembly direction. The first holding part 6 also has a limit stop 29 formed by a wall 28.

FIG. 2 shows the second holding part 8 with openings 14 configured to complement the protrusions 12. Moreover, the second holding part 8 has likewise spacer elements 22 which are configured to contact in an end position the shoulders 18 of the spacer elements 22 of the first mounting part 6. The second mounting part 8 also has frame means 24 formed by indentations 26.

FIG. 2 shows more clearly that the cavities 26 in the first holding part 6 and in the second holding part 8 are formed as a passageway 32 with an axial material edge 30 that prevents the battery cells 4 from sliding out. The battery cells 4 can be accessed and contacted from the outside via this passageway. The passageways 32 are formed in both the first holding part 6 and in the second holding part 8.

FIG. 3 shows the assembled device 2. The battery cells 4 are hereby arranged between the first holding part 6 and the second holding part 8. The first holding part 6 and the second holding part 8 are inserted into one another and contact each other at limit stop 20, thereby preventing further relative movement between the two holding parts in the assembly direction 10. FIG. 3 also illustrates that, after the first holding part 6 and the second holding part 8 have been assembled, the battery cells are contacted by a metal sheet 34, so that they cooperate in a battery pack.

Thus, while there have been shown and described and pointed out fundamental novel features of the invention as applied to a preferred embodiment thereof, it will be understood that various omissions and substitutions and changes in the form and details of the devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. For example, it is expressly intended that all combinations of those elements and/or method steps which perform substantially the same function in substantially the same way to achieve the same results are within the scope of the invention. Substitutions of elements from one described embodiment to another are also fully intended and contemplated. It is also to be understood that the drawings are not necessarily drawn to scale but that they are merely conceptual in nature. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.

Claims

1. A device for securing rechargeable battery cells in a battery pack, comprising:

a first holding part having protrusions extending in an assembly direction and being formed with a yieldable outer periphery, and

a second holding part having openings adapted to mate with the protrusions,

wherein the battery cells are interposed between the first holding part and the second holding part, and the first holding part and the second holding part are joined and affixed to one another by inserting the protrusions into the openings to form the battery pack.

2. The device of claim 1, wherein the protrusions are formed as pins.

3. The device of claim 1, wherein an outer periphery of the protrusions is tapered.

4. The device of claim 3, wherein the tapered outer periphery of the protrusions has a conical contour

5. The device of claim 3, wherein the taper of the protrusions encloses an angle of 0.5° to 3.0° with the assembly direction.

6. The device of claim 1, wherein the protrusions include a slot.

7. The device of claim 1, wherein the first holding part and the protrusions are formed as a single piece.

8. The device of claim 1, wherein the first holding part and the protrusions are formed from separate individual components.

9. The device of claim 1, wherein at least one of the first and second holding parts comprises spacer elements, with the spacer elements separating adjacent battery cells.

10. The device of claim 1, wherein the openings of the second holding part have a tapered inside contour.

11. The device of claim 10, wherein the inside contour of the openings has a conical shape.

12. The device of claim 1, wherein at least one of the first holding part and the second holding part comprises a frame which secures the battery cells against movement perpendicular to the assembly direction.

13. The device of claim 12, wherein the frame comprises openings or recesses in at least one of the first holding part and the second holding part.

14. The device of claim 12, wherein the frame comprises, in the assembly direction, a passageway extending through at least one of the first holding part and the second holding part, with the passageway providing external access to the battery cells.

15. The device of claim 1, wherein at least one of the first holding part and the second holding part is formed as an injection molded plastic part.

16. The device of claim 1, wherein at least one of the first holding part and the second holding part comprises a limit stop in the assembly direction.

17. The device of claim 16, wherein the limit stop is formed as a shoulder disposed on the protrusions perpendicular to the assembly direction.

18. The device of claim 16, wherein the device is configured for installation in a handheld electric tool.