JPH08290371A - Connecting structure of battery pack in electric tool - Google Patents

Abstract

PURPOSE: To keep an appropriate connecting condition without any defective contact in a simple constitution by providing an insertion hole in a connection face of a battery pack, and projectingly providing a connection terminal capable of being inserted into a battery holder corresponding to the insertion hole. CONSTITUTION: In a battery pack 1 where a plurality of storage batteries are stored in upper and lower storage battery cases 2, 3 made of a synthetic resin, the storage battery cases 2, 3 are integrated by welding, and a connection part 4 to be provided thereabove is provided with a pair of insertion holes 8a, 8b, positive and negative electrode terminal strips 11a, 11b provided on terminal holders above the storage batteries in the storage battery cases 2, and a thermo- terminal strip 12 in an exposed manner. In a storage battery holder 22 on an electric tool side, positive and negative spring terminals 24a, 24b are integrated with a terminal board 23 made of the synthetic resin to be held in an assembled condition by a receiving seat 21 in each handle housing 20, and the terminals 24a, 24b are inserted from the insertion holes 8a, 8b on the battery pack 1 to be electrically connected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connection structure between a battery pack accommodating a storage battery and a battery holder on the side of an electric tool on which the battery pack is detachably mounted.

[0002]

2. Description of the Related Art FIG. 10 shows a conventional connection structure.
Battery pack 4 containing multiple storage batteries (not shown)
0 is the handle housing 41, 4 of the electric tool
When mounted from the bottom of the handle 42 composed of 1,
At the same time as the battery pack 40 is accommodated in a predetermined storage portion in the handle 42, positive and negative electrode terminal plates 40a and 40b provided on the upper part thereof are projected on the terminal block 44 of the battery holder 43 fixed on the handle 42 side. The positive and negative spring terminals 45a and 45b hold the battery pack 40, and the upper part of the battery pack 40 is held and electrically connected.

[0003]

In the battery pack connection structure described above, the spring terminals 45a and 45b are provided.
Area of contact between the electrode terminal boards 40a and 40b (current carrying capacity)
However, if a motor such as a vibration drill or an electric hammer is a relatively large tool, the contact resistance between the spring terminal and the electrode terminal plate increases.
In particular, in the above vibrating tool, chattering (rubbing between contacts or momentary separation) may occur at the contact portion to cause a contact failure, so that the contact resistance further increases, and as a result, heat is generated to cause the electrode terminal plate 40a. , 40b are melted on the terminal holder made of synthetic resin, and the life of the storage battery is shortened on the battery side. Also, the electrode terminal board is
Since the spring terminal is always in contact with and separated from the same location, the contact surface of the battery pack is damaged due to long-term use of the battery pack, which also leads to poor contact.

[0004]

SUMMARY OF THE INVENTION Therefore, the present invention provides a battery pack connecting structure which does not have the above-mentioned contact failure and can maintain a suitable connected state with a simple structure. An insertion hole is provided on the connection surface of the battery pack, and a connection terminal that can be inserted in correspondence with the insertion hole is provided in the battery holder in a protruding manner. Further, it is preferable that the connection terminal has a bulging shape that expands in at least two opposing surface directions to generate a contact pressure when the connection terminal is inserted into the insertion hole. In addition, a pair of the insertion holes may be provided to include electrodes, and electrodes may be formed on the left and right outer surfaces adjacent to the connection surface. Further, the bulging shape of the connection terminal can be formed by symmetrically bending the conductive plates that are respectively superposed. Further, the bulging shape of the connection terminals can be formed by bending the conductive plates into a U shape. Further, it is preferable that the battery holder is provided with a protrusion that is formed along the connection terminal and that prevents the connection terminal from being bent.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is a battery pack in which a plurality of storage batteries (two above and six below, total 9.6 V) are housed in upper and lower battery cases 2 and 3 made of synthetic resin,
The battery cases 2 and 3 are integrated by welding. The battery pack 1 is provided with electrode terminal plates 11a and 11b, which are connected to the plus and minus sides of the storage battery, above the battery pack 1.
And a pair of mounting parts 5, which are connected to the lower end of the halved handle housing 20, 20 of the electric tool, below the connection part 4 including a thermo terminal plate 12 connected to a built-in thermostat. 5 and a locking portion 6 provided on the handle housing 20 and capable of locking a set plate described later are respectively provided. As shown in FIG. 2, the connecting portion 4 is formed on both side surfaces of the upper battery case 2 in the lateral direction, and a pair of side holes 7a and 7b are also cut out to the connecting surface 9 side.
And a pair of insertion holes 8a and 8b formed in the connection surface 9,
Then, from the vertical hole 4a provided on one end side in the longitudinal direction, the positive and negative electrode terminal plates 11a and 11b provided on the terminal holder 10 above the storage batteries 1a and 1a in the battery case 2 and the thermo terminal plate 12, respectively. The electrode terminal plates 11a and 11b are both exposed and are formed of a single conductive plate.
The U-shaped portion 13 worn on the lateral side walls 10a and 10b of the terminal holder 10 in the lateral direction, the horizontal portion 14, and the vertical portion 15 along the insulating wall 10c erected in the longitudinal direction at the center of the terminal holder 10. , And the contact portion 16 with the storage battery is bent. Therefore, when viewed from the insertion holes 8a and 8b, the electrode terminal plates 11a and 11b are exposed in two directions of the side wall portions 10a and 10b side of the terminal holder 10 and the insulating wall 10c side. Note that 8c and 8c are hanging pieces that are respectively hung in the lateral direction of the insertion holes 8a and 8b for dust prevention. By the way, the side surface 7a and the insertion hole 8 are formed in the connection surface 9.
a, since a bridging portion of the connecting surface 9 is formed between the side hole 7b and the insertion hole 8b, this bridging portion is the electrode terminal plate 1
The upper surfaces of the electrodes 1a and 11b are completely exposed to prevent both electrodes from being easily short-circuited.

On the other hand, the battery holder 22 on the electric tool side, which is connected when the battery pack 1 is mounted, is shown in FIG.
2, the positive and negative spring terminals 24 are attached to the synthetic resin terminal blocks 23 that are held in the assembled state by the seats 21 formed on the inner surface of each handle housing 20, respectively.
a and 24b are integrally provided, and the spring terminals 24a and 24b are inserted from the insertion holes 8a and 8b on the upper surface of the battery pack 1 to be electrically connected. Each spring terminal 24a, 24b is a thin conductive plate 25a,
25b is bent at the center and overlapped, and the bent side is projected above the terminal block 23 to connect with the lead wire on the electric tool side, and the end side is bent below the terminal block 23 in the direction away from each other. Bend it and hang it in parallel with a width slightly larger than the width in the lateral direction of the insertion holes 8a and 8b, and finally, tip the insertion holes 8a and 8b.
In order to make it easy to insert into a and 8b, they are circularly folded toward each other and brought into contact with each other to form bilaterally symmetrical bulging insertion portions 26a and 26b. Therefore, the spring terminals 24a and 24b are connected to the conductive plates 25a and 25b.
It has elasticity in the overlapping direction. On both sides of the terminal block 23, the insertion portions 26a,
A pair of projecting portions 23a, 23a extend in parallel with 26b.

In the connection structure constructed as described above,
When the battery pack 1 is inserted from the lower part of the handle housing 20, 20 of the electric tool with the battery holder 22 assembled as described above, the battery pack 3 is provided on the left and right mounting portions 5 of the battery case 3 as shown in FIGS. The hook portion 18 of the hook button 18 is biased outward by the leaf spring 17 and is prevented from coming out upward by the projections 5a, 5a.
a engages with the engaging portions 20a that are inwardly returned at the lower edge of the handle housing 20, and the locked state is maintained by the biasing of the leaf spring 17 as it is. At this time, the connection part 4
In the above, the two spring terminals 24a and 24b of the battery holder 22 are inserted into the insertion holes 8a and 8b, respectively, and the insertion portions 26a and 26b are pressed in the stacking direction. Since it is housed between the inner surface of each U-shaped portion 13 in 11b and the vertical portion 15, the insertion portions 26a and 26b generate a contact pressure in the expanding direction due to the elasticity thereof and the electrode terminal plate 11a, respectively. , 11b
Battery holder 2 with electrical connection
2 and the battery pack 1 are integrated. Further, as shown in FIGS. 3 and 4, the projecting portions 23a, 23a of the terminal block 23 come into contact with the connecting surface 9 of the battery case 2 to suppress the rattling of the battery holder 22. Even if vibration is applied by the vibrating tool, chattering hardly occurs. Further, since each electrode has a contact portion in two directions, a contact area can be secured wider than in the past, and the influence of contact resistance can be reduced even with a tool having a large load such as a vibration drill. In addition, these are spring terminal 24a, 24b which bent one board, and the electrode terminal board 11 which increased the contact on one side.
Since this can be achieved with a simple structure such as a and 11b, an increase in cost can be suppressed. On the other hand, the battery case 2 of the battery pack 1 is formed with a step portion 2a, and four corners of the step portion 2a are fitted to a pair of fitting portions 20b, 20b provided on the inner surface of each handle housing 20 in the mounted state. Since they also match each other, the action of suppressing the rattling of the battery pack 1 is exerted here as well. In the battery pack 1 of this embodiment, since the lower battery case 3 has the engaging portion 6 formed as described above, when the set plate 27 is axially attached to the handle housing 20, as shown in FIG. As described above, the set button 27 can be attached instead of the hook buttons 18, 18.

The battery pack 1 described in the above embodiment has the side hole 7a, in addition to the connection of the bulging spring terminals 24a, 24b from the insertion holes 8a, 8b.
7b allows the electrode terminal board 11 to be placed on both sides in the conventional manner.
Since a and 11b are exposed, the conventional outer grip type spring terminals 35a and 35b as shown in FIG.
It can also be used with a power tool equipped with. Thus, the battery holders 22 and 3 of both the conventional type and the present invention type
3, the contact surfaces of the electrode terminal plates 11a and 11b with the spring terminals can be used for the outside and the inside, so that the contact surfaces are less damaged and the increase in contact resistance can be suppressed. it can. Further, in the above embodiment, the insertion portions 26a, 26b of the spring terminals 24a, 24b are provided.
The end portions of the conductive plates 25a and 25b forming the conductive plate are separated from each other.
There is no problem even if the end portions of 5a and 25b are connected to each other to form a bulging shape. The bulging shape itself may be an elliptical shape, an oval shape, or a tubular shape having a slit in the axial direction, in addition to the above. A shape can be adopted, and both ends of the conductive plates 25a and 25b may be folded back toward the separating direction side instead of the other side. Further, in the above-mentioned embodiment, the battery holder 1 has been described as a 9.6V type, but of course the capacity and the shape of the battery case are not limited to those in the above-mentioned embodiment. In this embodiment, both spring terminals of the battery holder are formed integrally with the terminal block, but the spring terminals are directly extended to the switch of the electric tool to integrate the battery holder and the switch. Is also good.

Next, several examples of changing the spring terminal will be described. Note that the same reference numerals as those in the above-mentioned drawings indicate the same parts, and thus the description thereof will be omitted. In FIG. 5, positive and negative spring terminals 28a,
28b bends one conductive plate 29a, 29b respectively toward the center once under the terminal block 23, and has a lower end portion with a width slightly larger than the width of the insertion holes 8a, 8b in the lateral direction. The insertion portion 30 that is bent in a letter shape and bulges to the left and right
a and 30b are formed, and the spring terminals 28a and 28b are bilaterally symmetrical with their free ends being outside. Even in this shape, when the insertion portions 30a and 30b are respectively inserted into the insertion holes 8a and 8b, the elasticity of the insertion portions 30a and 30b causes a contact pressure in the lateral direction of each insertion hole to cause the electrode terminal plate 1 to be inserted.
The battery holder 22 and the battery pack 1 can be integrated with each other by being pressed against 1a and 11b and electrically connected. Further, in this embodiment, the bent portion near the center of the terminal block 23 is eliminated, and as shown in FIG.
The conductive plates 29a and 29b may be hung straight from the above to form only the U-shaped insertion portions 30a and 30b. Further, these U-shaped portions have the left and right sides opposite to the above with the free end being the inner side. It can be formed symmetrically. In the case of FIG. 6, the terminal block 23 is provided with protrusions 31 and 31 formed along the conductive plates 29a and 29b and having a width that can be accommodated in the U-shape of the insertion portions 30a and 30b. This prevents the spring terminals 28a and 28b from bending and coming into contact with each other when the other battery is inserted into the handle housing 20 by mistake, and the U-shaped free end falls inward to reduce elasticity. If the free end is on the inner side, the insertion portions 30a, 30 on both sides as shown in FIG.
You may form the one protrusion 32 which protrudes along the free end of b.

On the other hand, as shown in FIG. 8, two conductive plates 34 are provided.
a and 34b are hung from the terminal block 23 in parallel with a width slightly larger than the width of the insertion holes 8a and 8b in the lateral direction, and the respective lower ends are bent toward each other to form tapered insertion portions 35a and 35b. Alternatively, the spring terminals 33a and 33b may be used. Also in this case, as shown in FIGS. 6 and 7, the protrusions 31 and 31 extending from the terminal block 23 are interposed between the two conductive plates 34a and 34b, respectively, to prevent the conductive plates from being bent and the spring terminals 33a and 33b. It is preferable to provide a protrusion 32 between the terminals to prevent short circuit between both terminals.

In the above embodiment, the U-shaped spring terminal can be formed by using the conductive plates 36a and 36b bent in a wave shape as shown in FIG. According to this, even if the spring terminal is bent to some extent, the contact area with the electrode terminal plate can be stably obtained, and the reliability of electrical connection is enhanced. Further, the spring terminals may be formed by stacking a plurality of conductive plates instead of one. Further, in the above description, the battery pack is mounted, and the positive and negative electrode terminals on the storage battery side are electrically connected to the motor side of the electric tool. However, the present invention is not limited to this. It is also possible to adopt.

[0012]

As described above, according to the present invention, since the battery holder and the battery pack on the tool side are preferably integrated with a simple structure, chattering and an increase in contact resistance in a vibrating tool or the like. There is no problem of, and the battery can be used in a good energized state. Of course, the battery life is not affected. Further, when the connection terminal is formed into a bulging shape that expands in at least two opposing directions when inserting into the insertion hole to generate a contact pressure, the battery pack is more firmly attached by the connection terminal, A larger contact area can be secured than in the past. Further, when a pair of the insertion holes are provided and electrodes are provided respectively, and electrodes are also formed on the left and right outer surfaces adjacent to the connection surface, respectively, in addition to the electric tool having the battery holder of the present invention, the conventional grip type Since it can also be used in an electric tool for a battery holder having a spring terminal, the contact and separation surfaces of the electrode and the connection terminal are dispersed by using both of them together, and damage to the electrode side can be suppressed as much as possible. If the bulging shape of the connection terminal is formed by symmetrically bending the superposed conductive plates, the connection terminal can be formed by simple processing. Further, when the bulging shape of the connection terminal is formed by bending the conductive plate into a U shape, the processing is further simplified. Further, when the battery holder is provided with a protrusion formed along the connection terminal to prevent the connection terminal from being bent, the connection terminal can be effectively prevented from being bent or short-circuited even if the battery pack is erroneously installed. it can.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a battery pack and a handle housing.

FIG. 2 is an exploded perspective view of a connecting portion.

FIG. 3 is an explanatory diagram showing a connection structure between a battery pack and a battery holder.

FIG. 4 is an explanatory diagram showing a connection structure between a battery pack and a battery holder.

FIG. 5 is an explanatory diagram showing a modified example of a spring terminal.

FIG. 6 is an explanatory diagram showing a modified example of a spring terminal.

FIG. 7 is an explanatory diagram showing a modified example of a spring terminal.

FIG. 8 is an explanatory diagram showing a modified example of a spring terminal.

FIG. 9 is an explanatory diagram showing a modified example of a spring terminal.

FIG. 10 is an explanatory view showing a connection structure of a conventional battery pack.

[Explanation of symbols]

1 ... Battery pack, 2, 3 ... Battery case, 4 ...
・ Connecting parts, 5 ・ ・ Mounting parts, 6 ・ ・ Locking parts, 7a, 7b ・
・ Side holes, 8a, 8b ・ ・ Insertion holes, 9 ・ ・ Connecting surface, 10 ・
・ Terminal holders, 11a, 11b ・ ・ Electrode terminal plates, 12 ・
・ Thermo terminal board, 20 ・ ・ Handle housing, 22 ・
.Battery holders, 23 .. Terminal blocks, 24a, 24b
..Spring terminals, 26a, 26b ...

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoichi Kato 3-11-8 Sumiyoshi-cho, Anjo City, Aichi Prefecture Makita Co., Ltd.

Claims (6)

[Claims] 1. A battery pack connecting structure in which a battery pack accommodating a storage battery is mounted on a battery holder provided on a tool side and electrically connected to each other, wherein an insertion hole is provided on a connecting surface of the battery pack. ,
A connection structure for a battery pack in an electric power tool, wherein a connection terminal that can be inserted corresponding to the insertion hole is provided on the battery holder. 2. The battery pack for a power tool according to claim 1, wherein the connection terminal has a bulging shape that expands in at least two opposing surface directions to generate a contact pressure when the connection terminal is inserted into the insertion hole. Connection structure. 3. The battery for an electric power tool according to claim 1, wherein the pair of insertion holes are provided with electrodes, and the left and right outer surfaces adjacent to the connection surface are also provided with electrodes. Connection structure of the pack. 4. The connection structure for a battery pack in an electric power tool according to claim 2, wherein the bulging shape of the connection terminal is formed by symmetrically bending conductive plates that are superposed on each other. . 5. The connection structure for a battery pack in an electric power tool according to claim 2, wherein the bulging shape of the connection terminal is formed by bending a conductive plate into a U shape. 6. The battery pack connection in the electric power tool according to claim 1, wherein the battery holder is provided with a protrusion formed along the connection terminal to prevent the connection terminal from being bent. Construction.