Energy source device and outdoor walking vehicle

Abstract

The utility model discloses an energy source device and an outdoor walking vehicle, and the energy source device comprises a battery cavity; the battery cavity is provided with at least one accommodating area, and each accommodating area can accommodate a battery pack of a first specification size or a battery pack of a second specification size; wherein the bottom surface of the accommodating area is provided with a first bias element and a second bias element, when the accommodating area receives the first battery pack, the first bias element and the second bias element abut against the bottom surface of the first battery pack, and when the accommodating area receives the second battery pack, the first bias element and the second bias element abut against the bottom surface of the second battery pack. The bottom surface of the second battery pack abuts against the first bias element and does not abut against the second bias element. By the adoption of the technical scheme, thrust can be applied to the battery packs of various sizes and specifications, so that the battery packs of different sizes and specifications can be taken out conveniently.

Description

Technical Field

[0001] The present application relates to the field of outdoor gardening tools, and in particular to an energy source device and an outdoor walking vehicle. Background Art

[0002] With the advancement of battery technology, battery packs are increasingly being used in power tools. For example, electric riding lawn mowers have a battery compartment that receives a battery pack to power the vehicle. The battery pack can also be removed from the riding mower's compartment and installed in other garden tools, such as handheld mowers, pruners, garden blowers, and chainsaws. However, existing battery compartment mounting structures can only accommodate battery packs of the same specification and type, failing to accommodate battery packs of varying sizes. Summary of the Invention

[0003] The purpose of the present application is to provide a structure that can realize the installation of battery packs of different specifications and sizes in the same compartment, and in particular, a battery cavity structure that can adapt to battery packs of different specifications and sizes.

[0004] In order to achieve the above objectives, this application adopts the following technical solutions:

[0005] An energy source device includes a battery cavity for accommodating a battery pack, the battery cavity including at least one accommodating area, each accommodating area being capable of selectively receiving a first battery pack or a second battery pack; the bottom surface of the accommodating area having a first biasing element and a second biasing element, and when the accommodating area receives the first battery pack, the bottom surface of the first battery pack abuts against the first biasing element and the second biasing element; when the accommodating area receives the second battery pack, the bottom surface of the second battery pack abuts against the first biasing element but not the second biasing element.

[0006] Specifically, the size specification of the first battery pack is larger than the size specification of the second battery pack, and each accommodating area can receive one first battery pack or two second battery packs; wherein, the first battery pack and the second battery pack have the same nominal voltage but different electrical energy capacities.

[0007] Furthermore, a locking element is provided near the accommodating area, and the locking element locks with the surface of the first battery pack or the second battery pack to retain the first battery pack or the second battery pack within the accommodating area. Preferably, a locking element is provided at each end of the accommodating area, and the locking elements are provided on the inner wall of the battery cavity. When the accommodating area receives the first battery pack, the first battery pack is fixed in the battery cavity by the locking elements at both ends. When the accommodating area receives the second battery pack, the second battery pack is locked in the battery cavity by one of the locking elements. The first biasing element is provided near the locking element.

[0008] Furthermore, a first electrical connector and a second electrical connector are provided near the accommodating area. The first battery pack is provided with an electrical connection terminal on each side along its length, and the second battery pack is provided with an electrical connection terminal. When the accommodating area receives the first battery pack, the electrical connection terminals on both sides of the first battery pack are electrically connected to the first and second electrical connectors of the accommodating area, respectively. When the accommodating area receives the second battery pack, the electrical connection terminal of the second battery pack is electrically connected to one of the electrical connectors of the accommodating area. The first and second electrical connectors are symmetrical about the first center plane, and the second biasing element is provided near the first center plane. This ensures that the first battery pack is evenly stressed during its upward bounce, preventing the first battery pack from tilting during the bounce.

[0009] Preferably, when the accommodating area receives the second battery pack, the first biasing element is located at the center of the bottom surface of the second battery pack; the second biasing element is located on the first center plane, and when the accommodating area receives the first battery pack, the first center plane passes through the center of gravity of the first battery pack.

[0010] Furthermore, the battery cavity includes an opening for installing / removing the battery pack. When the battery pack is located in the battery cavity and the locking element is released from locking the battery pack, the battery pack pops out toward the opening under the push of the first biasing element and / or the second biasing element.

[0011] Furthermore, the first battery pack includes a plurality of first battery cells, which are arranged along a first direction, and electrode sheets are provided on both sides of the first battery cells, and the positive and negative poles of the first battery cells are respectively welded to the electrode sheets on both sides; the second battery pack includes a plurality of second battery cells, which are arranged along a second direction, and electrode sheets are provided on both sides of the second battery cells, and the positive and negative poles of the second battery cells are respectively welded to the electrode sheets on both sides; wherein, the arrangement direction of the first battery cells in the first battery pack is perpendicular to the ejection direction of the first battery pack, and the arrangement direction of the second battery cells in the second battery pack is perpendicular to the ejection direction of the second battery pack, thereby avoiding the positive / negative poles of the battery cells from impacting the electrode sheets during the ejection process of the battery pack and affecting the service life of the battery cells due to the flow of electrolyte inside the battery cells.

[0012] Furthermore, the first biasing element and the second biasing element are evenly distributed on the bottom surface of the accommodating area. Specifically, the first biasing element and the second biasing element are symmetrically distributed along the bottom edge of the accommodating area. In particular, when the accommodating area receives the first battery pack, the first biasing element and the second biasing element are supported at the edges of the first battery pack. Preferably, the bottom surface of the first battery pack is a quadrilateral, and the first biasing element and the second biasing element are located at the edges of the bottom surface of the first battery pack. The area S1 of the area enclosed by the line connecting the first biasing element and the second biasing element is greater than or equal to 1 / 2 of the area of ​​the bottom surface of the first battery pack.

[0013] Furthermore, the weight of the first battery pack is greater than or equal to 10 kg, and the weight of the second battery pack is greater than or equal to 2 kg. When the first battery pack or the second battery pack is placed in the accommodating area, the thrust provided by each biasing element is not less than 20 N.

[0014] Optionally, the first biasing element and the second biasing element have the same structure, and each biasing element includes an action element abutting against the battery pack and an elastic element applying a thrust to the action element.

[0015] Optionally, the acting element includes a rotating shaft end and an ejection end. Under the action of the thrust of the elastic element, the acting element can rotate around the rotating shaft end, and the ejection end of the acting element abuts against the battery pack.

[0016] Optionally, the energy source device can be installed on the frame of the riding lawn mower to serve as a power source for the riding lawn mower to provide a source of electricity for the riding lawn mower.

[0017] Optionally, the energy source device is a charger that can charge battery packs of different specifications, such as charging a first battery pack and a second battery pack.

[0018] Optionally, the energy source device is an energy storage power supply, and the surface of the energy source device has an AC output port and / or a DC output port. The energy source device converts the electrical energy of the first battery pack and / or the second battery pack and outputs it as a power source for external electrical devices.

[0019] Furthermore, the first battery pack and / or the second battery pack can be removed from the energy source device and installed on other cordless power tools to serve as power sources for the cordless power tools.

[0020] The energy source device provided by the present invention can adapt to the installation of battery packs of various sizes and specifications, thereby improving the selectivity of the battery packs, while also being able to conveniently and stably remove battery packs of different sizes and specifications. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without any creative effort based on these drawings.

[0022] Figure 1 A schematic diagram of a riding mower with an energy source device in an embodiment of the present application;

[0023] Figure 2 A schematic diagram of an energy source device in an embodiment of the present application;

[0024] Figure 3 A schematic diagram of an energy source device in an embodiment of the present application;

[0025] Figure 4 A schematic diagram of an energy source device in an embodiment of the present application;

[0026] Figure 5 A schematic diagram of an energy source device in an embodiment of the present application when a battery pack is not installed

[0027] Figure 6 A schematic diagram of an energy source device in an embodiment of the present application;

[0028] Figure 7 A schematic diagram of an energy source device in an embodiment of the present application when a battery pack is not installed

[0029] Figure 8 A schematic diagram of a battery cavity of an energy source device in an embodiment of the present application;

[0030] Figure 9 A schematic diagram of a battery cavity of an energy source device in an embodiment of the present application;

[0031] Figure 10 A schematic diagram of a first battery pack in an embodiment of the present application;

[0032] Figure 11 A schematic diagram of a second battery pack in an embodiment of the present application;

[0033] Figure 12 A schematic diagram of the arrangement of a first biasing element and a second biasing element in a containing area in an embodiment of the present application;

[0034] Figure 13 A schematic diagram of a biasing element in an embodiment of the present application;

[0035] Explanation of reference signs:

[0036] Energy source device-100; battery cavity-10; first biasing element-11; second biasing element-12; first battery pack-21; second battery pack-22; electrical connection terminal-201; sliding groove-202; acting element-101; pivot end-1011; ejection end-1012; elastic element-1013; fixing seat-1014; battery cavity cover-102; locking structure-103; unlocking button-1031; locking element-1032; electrical connector-104; sliding rail-105; outdoor walking vehicle-1000; walking wheel-1001; mowing mechanism-1002; vehicle frame-1003; first containing area-301; second containing area-302; third containing area-303; first central plane 300. DETAILED DESCRIPTION

[0037] For the purpose of promoting an understanding of the application, the application will be described in greater detail below with reference to the drawings. The preferred embodiments of the application are illustrated in the drawings. However, the application can be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and fully convey the scope of the application to those skilled in the art.

[0038] It should be noted that unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terms "above", "below", "left", "right", "vertical", "horizontal", and similar terms are used for explanation only and are not intended to limit the application. The term "and / or" includes any and all combinations of one or more of the associated listed items.

[0039] The specific structure of the energy source device 100 and the preferred embodiment of the outdoor walking vehicle 1000 comprising the energy source device 100 will be described below with reference to the accompanying drawings.

[0040] Example 1:

[0041] Reference Figure 1The present disclosure provides an outdoor walking vehicle 1000, which is specifically a riding lawn mower that can walk outdoors and mow grass. It is understandable that the outdoor walking vehicle 1000 can also be other vehicles that only walk outdoors, such as multi-purpose vehicles, beach cars, farmer's cars, golf carts, etc. The outdoor walking vehicle 1000 can also be a vehicle that can realize another function in addition to the walking function, such as a snowplow. A snowplow can not only walk outdoors but also realize the function of clearing snow. It can also be an agricultural machinery vehicle, such as a harvester, a sprayer, etc. In fact, as long as the outdoor walking vehicle 1000 adopts the essential content of the technical solution introduced below in this utility model, it falls within the scope of protection of this application.

[0042] like Figure 1 As shown, the outdoor walking vehicle 1000 includes a frame 1003; a seat, which is arranged on the frame 1003; a mowing mechanism 1002, which includes a mowing element and a mowing motor driving the mowing element; a walking mechanism, which includes a walking wheel 1001 and a walking motor for driving the walking wheel 1001; an energy source device 100, which is installed on the frame 1003 and is used to provide electrical energy to the riding lawn mower; Figure 2-5 As shown, the energy source device 100 includes: a battery cavity 10 capable of accommodating battery packs of different sizes, such as Figure 5 As shown, the battery chamber 10 includes a first accommodating area 301, a second accommodating area 302, and a third accommodating area 303. Each accommodating area can selectively receive at least one first battery pack 21 or two second battery packs 22. The battery chamber 10 also includes an opening for installing / removing the battery packs, which can be closed by a battery chamber cover 102. The first battery pack 21 and the second battery pack 22 are battery packs of different sizes, with the first battery pack 21 being a large-sized battery pack and the second battery pack 22 being a small-sized battery pack. For some professional users or professional gardening teams, during work, they not only need a riding lawn mower to mow lawns, but also use a pruner to trim branches, an edger to trim roadside weeds, and a blower to blow fallen leaves. The ability of a riding lawn mower to carry battery packs of different sizes facilitates interchangeability with battery packs on other cordless electric garden tools during outdoor work, expanding the battery pack's use scenarios. In some situations where battery life is required, a larger capacity battery pack can be replaced to meet the needs of longer working time.

[0043] like Figure 6-9As shown, the bottom surface of the accommodating area is provided with a first biasing element 11 and a second biasing element 12. The inner wall of the battery cavity 10 near the accommodating area is provided with a locking structure 103. This locking structure 103 locks the first battery pack 21 or the second battery pack 22 within the accommodating area of ​​the battery cavity 10. Once the locking structure 103 is released, the battery pack can be ejected toward the opening under the action of the first biasing element 11 and / or the second biasing element 12, allowing the user to remove the battery pack from the battery cavity 10. Furthermore, the abutment of the first biasing element 11 and the second biasing element 12 against the bottom surface of the first and / or second battery pack helps to reduce vibrations caused by the battery pack during operation of the riding lawn mower. Due to the different sizes of the first and second battery packs 21 and 22, improper placement of the biasing elements can cause the first and second battery packs 21 and 22 to tilt during ejection, preventing them from ejecting, thus hindering battery pack removal. Conventional biasing element placement within the battery compartment cannot accommodate the ejection of battery packs of varying sizes.

[0044] like Figure 2-5 As shown, battery packs of different sizes can be accommodated in the first accommodating area 301, the second accommodating area 302, and the third accommodating area 303. When the accommodating area receives the first battery pack 21, the bottom surface of the first battery pack 21 abuts the first biasing element 11 and the second biasing element 12. When the accommodating area receives the second battery pack 22, the bottom surface of the second battery pack 22 abuts the first biasing element 11 but not the second biasing element 12. Because the volume and weight of the first battery pack 21 are greater than those of the second battery pack 22, using only the first biasing element 11 will cause the first battery pack 21 to tilt during the upward rebound process or make it impossible to remove the first battery pack 21 due to insufficient elastic force. If both the first biasing element 11 and the second biasing element 12 are used when receiving the first battery pack 21 and the second battery pack 22, the lighter second battery pack 22 will need to overcome a greater elastic force during insertion, making installation of the second battery pack 22 more difficult. Among them, "first" and "second" are only used to distinguish different bias element arrangements. The structures of the first bias element 11 and the second bias element 12 can be the same or different, which does not affect the implementation of the solution of the present application.

[0045] like Figure 7-9As shown, a battery pack locking structure 103 is provided on the inner wall of the battery cavity 10 adjacent to the accommodating area. The locking structure 103 includes a locking element 1032 and an unlocking button 1031. The locking element 1032 is a locking tongue protruding from the inner wall of the battery cavity 10. The first battery pack 21 and the second battery pack 22 have a slot on their surfaces. The locking element 1032 locks with the slot on the surface of the first battery pack 21 or the second battery pack 22 to retain the first battery pack 21 or the second battery pack 22 within the accommodating area. By toggling the unlocking button 1031, the locking element 1032 moves to release the lock on the first battery pack 21 or the second battery pack 22. The first biasing element 11 is provided adjacent to the locking element 1032.

[0046] The battery cavity 10 is further provided with a first electrical connector 104 and a second electrical connector 104 adjacent to the receiving area. The first electrical connector 104 and the second electrical connector 104 can be selectively connected to the electrical connection terminal 201 on the first battery pack 21 or the second battery pack 22 to provide power to the riding lawn mower. Figure 10 、 Figure 11 As shown, the first battery pack 21 is in a cubic shape, with electrical connection terminals 201 and slide slots 202 provided on both sides thereof, and each second battery pack 22 has one electrical connection terminal 201 and one slide slot 202; Figure 7 As shown, when the accommodating area receives the first battery pack 21, the electrical connection terminals 201 on both sides of the first battery pack 21 remain connected to the first electrical connector 104 and the second electrical connector 104 respectively; when the accommodating area receives two second battery packs 22, the first electrical connector 104 of the accommodating area is connected to the electrical connection terminal 201 of one of the second battery packs 22, and the second electrical connector 104 of the accommodating area is connected to the electrical connection terminal 201 of the other second battery pack 22; the slide groove 202 on the battery pack cooperates with the slide rail 105 in the battery cavity 10 to smoothly install the battery pack in the battery cavity 10. Among them, the "first" and "second" in the first battery pack 21 and the second battery pack 22 are used to distinguish battery packs of different sizes; as shown Figure 8-9 、 Figure 12 As shown, the accommodating area has a first center plane 300, the first electrical connector 104 and the second electrical connector 104 are symmetrical about the first center plane 300, and the second biasing element 12 is arranged close to the first center plane 300; preferably, the second biasing element 12 is arranged on the first center plane 300, so that the first battery pack 21 can be popped out in a direction perpendicular to the bottom surface of the battery cavity 10, thereby facilitating the disassembly of the first battery pack 21 and avoiding tilting during the pop-up process to cause the battery pack to be disassembled unsmoothly.

[0047] In this embodiment, the first battery pack 21 includes a plurality of first battery cells, each of which has connecting plates on both sides, and the battery cells and the connecting plates are connected by laser welding. When the first battery pack 21 is placed in the accommodation area of ​​the battery cavity 10, the arrangement direction of the first battery cells in the first battery pack 21 is perpendicular to the ejection direction of the first battery pack 21. During the ejection process of the battery pack, the electrolyte in the battery cell will collide with the positive or negative terminal inside the battery cell due to inertia, and the battery cell and the electrode sheet will also impact due to inertia, which can easily lead to instability in the battery cell and detachment of the welding point between the battery cell and the electrolyte sheet. The battery cell arrangement direction of the present application solution can prevent this situation.

[0048] like Figure 12 As shown, the first biasing element 11 and the second biasing element 12 are evenly distributed on the bottom surface of the accommodating area. In this embodiment, two first biasing elements 11 are symmetrically arranged along the length direction of the bottom surface of the accommodating area, and two second biasing elements 12 are symmetrically arranged along the width direction of the bottom surface of the accommodating area. When the accommodating area receives the second battery pack 22, the first biasing element 11 is approximately in contact with the center of the bottom surface of the second battery pack 22. When the accommodating area receives the first battery pack 21, the first biasing element 11 and the second biasing element 12 are adjacent to the bottom edge of the first battery pack 21. The four biasing elements are used to push the first battery pack 21 upward, ensuring the upward thrust of the first battery pack 21 while preventing the first battery pack 21 from tilting during the rebound process and causing an uneven rebound. Preferably, the area S1 enclosed by the first biasing element 11 and the second biasing element 12 is greater than or equal to 1 / 2 of the bottom surface area of ​​the accommodating area. When the accommodating area receives the first battery pack 21, the first battery pack 21 substantially fills the accommodating area. In this embodiment, the weight of the first battery pack 21 is approximately 15 kg, the weight of the second battery pack 22 is approximately 3.5 kg, and the elastic force provided by each biasing element is approximately 35 N.

[0049] The first biasing element 11 and the second biasing element 12 are formed as follows Figure 13 In the structure shown, the biasing element includes: an active element 101 that directly abuts the battery pack, an elastic element 1013 that applies thrust to the active element 101, and a fixing seat 1014 that limits the position of the active element 101 and the elastic element 1013. The active element 101 includes a rotating shaft end 1011 and an ejection end 1012. The ejection end 1012 can rotate about the rotating shaft end 1011 under the action of the elastic element 1013. The ejection end 1012 of the active element 101 abuts the battery pack, and the elastic element 1013 is disposed between the active element 101 and the fixing seat 1014. This modular biasing element can be directly installed at the bottom of the battery chamber 10 of the energy source device 100, simplifying installation.

[0050] Example 2:

[0051] like Figure 7-9 As shown, the energy source device 100 in this embodiment is a portable energy storage power supply, which has the function of charging the first battery pack 21 and / or the second battery pack 22, and / or the function of converting the electrical energy of the first battery pack 21 and / or the second battery pack 22 and outputting it. The surface of the energy source device 100 has an AC output port and / or a DC output port (not shown). The energy source device 100 converts the electrical energy of the battery pack into AC power or DC power with a voltage different from the battery pack and outputs it from the output port to power an external AC power device or DC power device. Figure 7 As shown, in this embodiment, the energy source device 100 can accommodate one first battery pack 21 or two second battery packs 22. The energy source device 100 includes a battery cavity 10 capable of accommodating the first battery pack 21 or the second battery pack 22. The battery cavity 10 includes a accommodating area, and the bottom of the accommodating area has a biasing element. The setting of the biasing element is basically the same as the setting of the first biasing element 11 and the second biasing element 12 in Example 1.

[0052] The above is only a preferred specific implementation method of the present application, but the scope of protection of the present application is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes based on the technical solution and application concept of the present application within the technical scope disclosed in the present application, and they should be covered by the scope of protection of the present application.

Claims

1. An energy source device, comprising a battery cavity for accommodating a battery pack, characterized in that: The battery cavity includes at least one accommodating area, at least one of which can selectively receive the first battery pack or the second battery pack; wherein, The bottom surface of the accommodating area is provided with a first biasing element and a second biasing element. When the accommodating area receives a first battery pack, the bottom surface of the first battery pack abuts against the first biasing element and the second biasing element; when the accommodating area receives a second battery pack, the bottom surface of the second battery pack abuts against the first biasing element but not against the second biasing element.

2. The energy source device according to claim 1, characterized in that: The volume of the first battery pack is greater than that of the second battery pack, and the accommodating area can receive one first battery pack or multiple second battery packs.

3. The energy source device according to claim 1, characterized in that: A locking element is provided near the accommodating area, and the locking element is locked with the surface of the first battery pack or the second battery pack to keep the first battery pack or the second battery pack within the accommodating area; wherein the first biasing element is provided near the locking element.

4. The energy source device according to claim 1, characterized in that: A first electrical connector and a second electrical connector are arranged near the accommodating area, and the first electrical connector and the second electrical connector can be selectively connected to the electrical connection terminals of the first battery pack or the second battery pack; wherein, the first electrical connector and the second electrical connector are symmetrical about the first center plane, and the second biasing element is arranged close to the first center plane.

5. The energy source device according to claim 4, characterized in that: The second biasing element is located on the first center plane.

6. The energy source device according to claim 3, characterized in that: The battery cavity includes an opening for installing / removing the battery pack. When the battery pack is located in the battery cavity and the locking element is released from locking the battery pack, the battery pack pops out toward the opening under the action of the first biasing element and / or the second biasing element.

7. The energy source device according to claim 6, characterized in that: The first battery pack includes a plurality of first battery cells, and the first battery cells are arranged along a first direction; The second battery pack includes a plurality of second battery cells, and the second battery cells are arranged along the second direction; wherein, The first direction is perpendicular to the second direction.

8. The energy source device according to claim 6, characterized in that: The first battery pack includes multiple first battery cells, the second battery pack includes multiple second battery cells, and the first battery cells and / or the second battery cells are arranged in the same direction; wherein the arrangement direction of the first battery cells and / or the second battery cells is perpendicular to the ejection direction of the battery pack.

9. The energy source device according to claim 1, characterized in that: The first biasing element and the second biasing element are evenly distributed on the bottom surface of the accommodating area. When the accommodating area receives the first battery pack, the first biasing element and the second biasing element are located at the bottom edge of the first battery pack; wherein, An area S1 of a region enclosed by the first biasing element and the second biasing element is greater than or equal to 1 / 2 of an area S2 of a bottom surface of the first battery pack.

10. The energy source device according to claim 2, characterized in that: The weight of the first battery pack is greater than or equal to 10 kg, and the weight of the second battery pack is greater than or equal to 2 kg; when the second battery pack is received in the accommodating area, the elastic force provided by the first biasing element is greater than or equal to 20 N; when the first battery pack is received in the accommodating area, the elastic forces provided by the first biasing element and the second biasing element are both greater than or equal to 20 N.

11. The energy source device according to claim 1, characterized in that: The first biasing element and the second biasing element have the same structure, including: an action element abutting against the battery pack and an elastic element applying a thrust to the action element.

12. The energy source device according to claim 11, characterized in that: The action element includes a rotating shaft end and an ejection end. The action element rotates around the rotating shaft end under the action of the elastic element, and the ejection end of the action element abuts against the battery pack.

13. The energy source device according to claim 1, characterized in that: The energy source device includes a charger or an energy storage power supply; The first battery pack and / or the second battery pack is a battery pack that can be removed from the energy source device and can power another electric tool.

14. An outdoor walking vehicle, characterized by: It includes a frame, a walking mechanism supporting the frame and an energy source device according to any one of claims 1 to 12, the walking component includes walking wheels and a walking motor, and the energy source device is fixed on the frame and serves as the power source of the outdoor walking vehicle to provide a source of electricity for the walking motor.

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