JP6009491B2 - Battery pack - Google Patents

Description

  The present invention relates to a battery pack configured to be attachable to a tool body of a power tool as a power source of the power tool.

2. Description of the Related Art Conventionally, an electric tool includes a tool main body that is electrically driven and a battery pack that serves as a driving power source for the tool main body. The battery pack is configured to be detachable from the tool body. The battery pack includes a housing case that forms an exterior, and a battery body that is installed in the housing case. The battery body includes a plurality of chargeable / dischargeable battery cells and a control board that controls charge / discharge. In the plurality of battery cells, lead plates are connected to the electrodes in order to electrically connect the battery cells in series or in parallel.
On the other hand, the above-described electric tool may be used outdoors. Therefore, such battery packs may be splashed with water, such as raindrops, and water may enter the case. Here, if water enters the case and the above lead plates are immersed in water, the unintended lead plates are electrically connected to each other, and the electricity stored in the battery cell is leaked. It can also be letting you.
Therefore, in such a battery pack, in order to drain the water that has entered the housing case out of the housing case, a battery pack having a drainage hole in the bottom portion of the housing case is known (for example, Patent Document 1). According to this battery pack, the water that has entered the housing case can be drained out of the housing case through the drainage hole, and the lead plate can be prevented from being immersed in water, The electricity stored in the battery cell is not allowed to leak.

JP 2006-196277 A

On the other hand, in order to enhance the above-described drainage effect, it is considered to provide a large number of the above-described drainage holes in the bottom portion of the housing case.
However, if a large number of the drainage holes are simply provided in the bottom portion of the housing case, water and dust easily enter the housing case from the drainage holes. Therefore, it is desirable to keep the number of holes for drainage as small as possible while enhancing the drainage effect described above.

  The present invention has been made in view of such circumstances, and a problem to be solved by the present invention is a battery pack configured to be attachable to the tool body of the electric tool as a power source of the electric tool. In order to prevent the leakage of electricity stored in the battery cell, water entering the case can be efficiently drained outside the case, and the number of drain holes is kept as small as possible. There is.

In solving the above-described problems, the battery pack according to the present invention employs the following means. That is, the battery pack according to the first aspect of the present invention is a battery pack configured to be attachable to the tool main body of the electric tool as a power source of the electric tool, and includes a casing case forming an exterior, and the casing A plurality of battery cells installed in the case, the bottom portion of the casing case having a drain hole communicating with the inside and outside of the casing case, the water entering the casing case A drainage function shape portion having a function of discharging to the outside of the housing case is provided, and an arrangement position of the drainage function shape portion is at least between terminal members connected to the electrodes of the battery cell. It is characterized by being set.
In addition, the drainage functional shape portion may be configured to include the drainage hole communicating with the inside and outside of the housing case, and even if the drainage function shape portion is configured only by the drainage hole, It means that it may be configured to include a drain hole and a structure for guiding to the drain hole.

According to the battery pack according to the first aspect of the present invention, the disposition position of the drainage function shape portion disposed on the bottom portion of the housing case is at least between the terminal members connected to the electrodes of the battery cell. Accordingly, the water between the terminal members can be discharged from the inside of the housing case to the outside of the housing case. Thereby, it can drain so that the water between at least terminal members may be lost, and it can prevent mutual electrical connection by the terminal members being immersed in water. That is, even if an appropriate rib shape is formed in the housing case so as to support the battery cell, at least the terminal members are immersed in water while allowing water accumulation by the rib shape. It can be prevented.
Therefore, when the terminal members are immersed in water, unintended electrical connection between the terminal members can be prevented. That is, water that has entered the housing case can be efficiently drained out of the housing case so as to prevent leakage of electricity stored in the battery cell. In addition, since the drain holes to be disposed are suppressed to the minimum locations that can prevent unintended electrical connection between the terminal members, the number of drain holes can be kept as small as possible. .

The battery pack according to the second invention is the battery pack according to the first invention,
The terminal members that set the disposition position of the drainage functional shape portion have a mutual disposition relationship along the adjacent direction of the electrodes of the plurality of battery cells that are arranged in parallel so that the electrodes are adjacent to each other. The terminal members are adjacent to each other and have different potentials.
According to the battery pack according to the second aspect of the present invention, the terminal members that set the disposition position of the drainage function shape portion are terminal members that are adjacent to each other and have different electric potentials. It is possible to set a location for draining so that there is no gap between terminal members that are adjacently arranged and have different potentials. As a result, it is possible to set a place where the terminal member is desired to be drained so as to be free of water and to be kept in an insulated state, where a short circuit between the terminal members is likely to occur. It can be certain.

The battery pack according to a third aspect of the present invention is the battery pack according to the first or second aspect of the present invention, wherein an outer side edge of the drainage hole disposed outside the housing case is at least the outer side edge. It is characterized in that it is set and formed in a shape that rises toward the inside of the housing case from the peripheral part of the housing.
According to the battery pack of the third aspect of the invention, the outer edge of the drainage hole disposed outside the housing case is shaped to rise toward the inside of the housing case at least from the peripheral portion of the outer edge. Is set to be formed. As a result, even when the battery pack attached to the tool body is placed on the desk or the ground and the bottom part of the battery pack is in contact with the placement surface of the desk or the ground, the outside of the drainage hole The end edge will be positioned higher than the placement surface. Therefore, the drain hole can be prevented from being blocked by the mounting surface, and the water that has entered the housing case can be discharged from the drain hole to the outside of the housing case. In addition, since a slight gap can be formed between the outer edge of the drain hole and the mounting surface, the surface tension of the water that has entered the gap is utilized in the housing case. Water can be easily guided out of the housing case. Therefore, the water that has entered the housing case can be efficiently drained out of the housing case.

The battery pack according to a fourth aspect of the present invention is the battery pack according to any one of the first to third aspects of the present invention, wherein the drainage function shape portion is configured to flow water so that water flows toward the drainage hole. A flow guide means for guiding, wherein the flow guide means is formed as a drainage path in which the bottom portion inside the casing case is inclined toward the bottom of the bottom portion as it goes to the drainage hole. It is characterized by being.
According to the battery pack of the fourth invention, the flow guide means is formed as a drainage path in which the bottom part inside the housing case is inclined toward the bottom part lower side as it goes to the drainage hole. The water that has entered the housing case can flow toward the drainage hole by the inclined structure of the drainage path. As a result, not only the periphery of the drainage hole but also the drainage performance of the portion that becomes the drainage path can be enhanced, and the range in which the drainage performance is desired to be increased can be expanded.
In addition, as an arrangement | positioning location of this drainage path, it may exist between the terminal members connected to the electrode of a battery cell, and may exist other than between these terminal members. . Further, in this drainage path, it is sufficient that the inner surface of the bottom portion is formed in an inclined shape, and the outer surface of the bottom portion is formed in a flush shape. Good.

The battery pack according to a fifth aspect of the present invention is the battery pack according to any one of the first to fourth aspects, wherein the drainage function shape portion draws water so that the water collects toward the drainage hole. A pull-in guide means for guiding is provided, and the pull-in guide means extends in a concave groove shape from the inner side edge of the drainage hole disposed inside the case case to the inner side surface of the case case. And is formed as a lead-in groove that acts to draw water toward the drain hole.
According to the battery pack of the fifth aspect of the present invention, the retraction guide means is a retraction groove that extends in a concave groove shape from the inner side edge of the drainage hole disposed inside the case case to the inner side surface of the case case. Therefore, the water existing around the inner side edge can be drawn into the drain hole. Thus, the drainage can be extended to the periphery of the drainage hole so that there is no water between the terminal members. Therefore, prevention of mutual electrical connection due to the terminal members being immersed in water can be made more reliable.

A battery pack according to a sixth aspect of the present invention is the battery pack according to any one of the first to fifth aspects of the invention, wherein the drainage is performed in a state in which the drainage hole is maintained inside the housing case. A foreign substance intrusion restricting rib is provided to cross the opening shape of the hole inside the housing case.
In the battery pack according to the sixth aspect of the present invention, the foreign matter intrusion restricting rib that crosses the opening shape of the drain hole inside the casing case is disposed inside the casing case. Even when foreign matter is likely to enter the inside from the outside of the housing case, the foreign matter intrusion restricting rib can prevent the foreign matter from entering. Thereby, the inside of the housing case can be maintained in a clean state.

The battery pack according to a seventh aspect of the present invention is the battery pack according to any one of the first to sixth aspects, wherein the drainage hole is disposed between the terminal members. The arrangement position of one or both of the flow guide means and the retraction guide means is set to a position different from the position between the terminal members.
According to the battery pack according to the seventh aspect of the present invention, since the drain holes are disposed so that the drain holes are located between the terminal members, the water between the terminal members is removed from the interior of the housing case. Can be drained to the outside. As a result, the water around the drain hole can be guided to the drain hole by the flow guide means or the pull-in guide means, and the water between these terminal members can be completely eliminated due to the presence of the drain hole. Unintentional electrical connection between members can be reliably prevented.

The battery pack according to an eighth aspect of the present invention is the battery pack according to any one of the first to sixth aspects, wherein at least a part of one or both of the flow guide means and the retracting guide means is It is set so that it may exist between terminal members, The arrangement | positioning position of the said drain hole is set to the position different from the position between said terminal members, It is characterized by the above-mentioned.
According to the battery pack of the eighth aspect of the invention, the position of the drain hole is set to a position different from the position between the terminal members, and either one of the flow guide means and the retraction guide means or It is set so that at least a part of both exists between the terminal members. Accordingly, water between the terminal members can be drained from the inside of the casing case to the outside, and the position of the drain hole is set to an appropriate portion of the casing case according to the design of the battery pack. be able to. Therefore, the freedom degree of the arrangement | positioning position of a drain hole can be raised, and the freedom degree in the design of a battery pack can also be raised.

According to the battery pack of the first aspect of the present invention, the water that has entered the housing case can be efficiently drained out of the housing case so as to prevent leakage of electricity stored in the battery cells. The number of holes can be kept as small as possible.
According to the battery pack of the second invention, the location where the insulation state is desired to be maintained can be set to a location where the short-circuit between the terminal members is likely to occur, and the short-circuit can be prevented more reliably.
According to the battery pack according to the third aspect of the invention, the drainage hole can be prevented from being blocked by the mounting surface, and the water in the housing case can be easily guided out of the housing case.
According to the battery pack of the fourth aspect of the invention, not only the vicinity of the drain hole but also the drainage of the portion that becomes the drainage path can be enhanced, and the range in which the drainage is desired to be increased can be expanded.
According to the battery pack which concerns on 5th invention, prevention of the mutual electrical connection by the terminal members being immersed in water can be made more reliable.
According to the battery pack of the sixth invention, the inside of the housing case can be maintained in a clean state.
According to the battery pack of the seventh invention, water between the terminal members can be completely eliminated due to the presence of the drain holes, and unintended electrical connection between the terminal members can be reliably prevented. .
With the battery pack according to the eighth aspect of the invention, the degree of freedom of the location of the drain holes can be increased, and the degree of freedom in designing the battery pack can also be increased.

It is a disassembled perspective view which shows the battery pack of 1st Embodiment. It is a bottom view which shows the case where the battery pack of FIG. 1 is seen from the bottom. It is sectional drawing which shows the III-III cross-section arrow of the battery pack of FIG. It is sectional drawing which shows the IV-IV cross-section arrow of the battery pack of FIG. It is sectional drawing which shows the VV cross-section arrow of the battery pack of FIG. It is sectional drawing which expands and shows the arrangement | positioning part of a drain hole among the case main bodies of FIG. It is a top view which shows the case main body seen from the upper surface in the state which can see the inside. It is a top view which expands and shows the arrangement | positioning part of a drain hole among case bodies. It is sectional drawing of the battery pack which shows the example provided with the drainage path. It is an enlarged top view of the drain hole which shows the example in which the drawing groove | channel was provided. It is a perspective view which shows the case main body which looked in the state which can see the inside. It is sectional drawing which shows the XII-XII cross-section arrow of the case main body of FIG.

[First Embodiment]
A first embodiment for implementing a battery pack according to the present invention will be described below with reference to the drawings of FIGS.
The exploded perspective view of FIG. 1 shows the battery pack 10 of the first embodiment. In this exploded perspective view, the battery pack 10 is shown in an exploded state in which the inside of the battery pack body 40 can be seen. In the following description, the electrical connection side of the battery pack 10 is defined as the upper side, and the slide mounting direction of the battery pack 10 is defined as the front side.
The battery pack 10 is configured to be detachable by sliding it on a tool main body (attachment tool) of an electric tool represented by an electric driver, for example. The battery pack 10 serves as a drive power source for the mounted tool body. Therefore, the battery pack 10 is removed from the tool body when the amount of charge decreases, and is charged by an external dedicated charger (attached tool). Function as.
As shown in the exploded perspective view of FIG. 1, the battery pack 10 generally includes a housing case 20 and a battery pack main body 40. The housing case 20 is configured in a case shape that incorporates the battery pack main body 40 and forms an exterior. A battery pack body 40 is installed in the housing case 20.

Before describing the case 20, the configuration of the battery pack body 40 will be described.
The battery pack main body 40 is built in a case 20 that will be described in detail later. As shown in FIG. 1, the battery pack main body 40 roughly includes a plurality of battery cells 41, a connection control board 51, and a male hook mechanism 55. Prepare.
The battery cell 41 is a widely used chargeable / dischargeable battery cell. As shown in FIG. 1, the battery cells 41 of the battery pack main body 40 are arranged in parallel so that a total of ten battery cells 41 are arranged in two stages, and the electrodes 42 are adjacent to each other. Specifically, a total of ten battery cells 41 are arranged side by side in two stages so that the electrodes 42 of the battery cells 41 are positioned on the left and right sides of the battery pack 10. In describing the battery cells 41 arranged side by side in this manner, the first battery cell 410, the second battery cell 411, the third battery cell 412, and the second battery cell 413 are sequentially arranged from the upper side and the front side of the battery pack 10. ,... Are attached. Further, the lead end of the lead wire of the electrode 42 of the battery cell 41 shown in the figure is a round pot portion in the lead plate 45. However, the lead wire is drawn out with respect to the end portion of the battery cell 41 located at the round pot portion of the lead plate 45.
As described above, the battery cells 41 arranged side by side have their respective electrodes 42 positioned at the left and right ends of the battery pack 10. That is, ten electrodes 42 of each battery cell 41 are positioned on both left and right ends of the battery pack 10. A lead plate 45 that is electrically connected is attached to each of the electrodes 42 of the battery cells 41. Specifically, the electrically connected left lead plate 46 is attached to the electrodes 42 of the ten battery cells 41 located at the left end, and the ten battery cells located at the right end are attached. An electrically connected right lead plate 47 is attached to the electrode 42 of 41. The left lead plate 46 and the right lead plate 47 correspond to the terminal members according to the present invention, and function as plate terminals that are widely used. In addition, the lead plate 45 (the left lead plate 46 and the right lead plate 47) whose one side is connected to the electrode 42 of the battery cell 41 in this way is electrically connected to the connection control board 51 described below on the other side. Has been. The left lead plate 46 and the right lead plate 47 will be described in detail later.

Next, the connection control board 51 and the male hook mechanism 55 will be described.
The connection control board 51 is electrically connected to the chargeable / dischargeable battery cell 41 and controls charging / discharging of the battery cell 41. That is, the connection control board 51 is disposed on the upper side of the plurality of battery cells 41 described above, and generally includes a control board 52 and a connection terminal portion 53 provided on the control board 52. The control board 52 performs appropriate electrical control when charging and discharging the battery cells 41. The connection terminal portion 53 is a terminal that is electrically connected to a tool body (not shown) or a dedicated charger that is to be attached. That is, the connection terminal portion 53 is a plus connection terminal 531 that is connected to, for example, a plus terminal on the tool body side, which is an attachment tool, for example, a minus connection terminal 532 that is connected to a minus terminal on the tool body side, 3 types of connection terminals including a control connection terminal 533 connected to the control terminal on the side. These connection terminal portions 53 are formed by disposing plate spring-shaped metal terminals so as to face each other.
The male hook mechanism 55 includes a structure that is detachably locked with respect to the tool body when, for example, the tool body is slidably mounted on the tool body. Therefore, the male hook mechanism 55 is configured to have a hook shape that locks against the tool body and a finger hook shape that performs a release operation. Specifically, the male hook mechanism 55 includes a hook-shaped structure 56 having such a hook shape and a finger hook shape, and a biasing spring 57 that biases the hook-shaped structure 56 in the locking direction. Prepare. The male hook mechanism 55 configured as described above is slidably mounted on the tool main body, and the hook-shaped structure 56 is automatically locked to the tool main body by the biasing force of the biasing spring 57. Further, when the release operation is performed against the urging force of the urging spring 57, the hook-shaped structure 56 is released from being locked with respect to the tool body. When the battery pack 10 is slid in this state, the tool is released. Can be removed from the body.

Next, the left lead plate 46 and the right lead plate 47 will be described in detail.
The left lead plate 46 and the right lead plate 47 are each configured by a plate-shaped terminal, and are attached across the electrodes 42 of the plurality of battery cells 41.
The bottom view of FIG. 2 shows the battery pack 10 as viewed from below. The cross-sectional view of FIG. 3 shows the III-III cross-sectional arrow of the battery pack 10 in FIG. 2 so that the left lead plate 46 located on the left side of the battery pack 10 can be seen. The cross-sectional view of FIG. 4 shows an IV-IV cross-sectional arrow of the battery pack 10 in FIG. 2 so that the right lead plate 47 located on the right side of the battery pack 10 can be seen.
As shown in FIG. 3, the left lead plate 46 is formed by three plate terminals that are separated from each other. The three left lead plates 46 are denoted by reference numerals in order from the front side: a first left lead plate 461, a second left lead plate 462, and a third left lead plate 463. That is, as shown in FIG. 3, the first left lead plate 461 has two left electrodes 42 of the first battery cell 410 and the second battery cell 411 with respect to the ten electrodes 42 at the left end of the battery cell 41. Attached across the. The second left lead plate 462 is attached across the four left electrodes 42 of the third battery cell 412, the fourth battery cell 413, the fifth battery cell 414, and the sixth battery cell 415. The third left lead plate 463 is attached across the four left electrodes 42 of the seventh battery cell 416, the eighth battery cell 417, the ninth battery cell 418, and the tenth battery cell 419.
In other words, as shown in FIG. 3, the first left lead plate 461 and the second left lead plate 462 include a first battery cell 410 and a second battery cell 411, a third battery cell 412 and a fourth battery cell. The battery cells 413 are separated from each other so as to be separated and separated from each other. The first left lead plate 461 and the second left lead plate 462 that are adjacent to each other are arranged as lead plates 45 having different potentials. In addition, the second left lead plate 462 and the third left lead plate 463 separate the fifth battery cell 414 and the sixth battery cell 415 from the seventh battery cell 416 and the eighth battery cell 417. In addition, they are arranged apart from each other so as to be electrically disconnected from each other. The second left lead plate 462 and the third left lead plate 463 that are adjacent to each other are arranged as lead plates 45 having different potentials. That is, the left lead plates 46 (461, 462, 463) are individually adjacent to each other so as to be along the adjacent direction of the electrodes 42 of the ten battery cells 41 arranged in parallel. In addition, the potentials are different from each other.

Further, the right lead plate 47 is also formed by three plate-shaped terminals separated separately as shown in FIG. The three right side lead plates 47 are denoted by reference numerals in order from the front side: a first right side lead plate 471, a second right side lead plate 472, and a third right side lead plate 473. That is, as shown in FIG. 4, the first right lead plate 471 has the first battery cell 410, the second battery cell 411, the third battery cell 412, the first battery cell 41, and the ten electrodes 42 at the right end of the battery cell 41. The four battery cells 413 are attached across the four right electrodes 42. The second right lead plate 472 is attached across the four right electrodes 42 of the fifth battery cell 414, the sixth battery cell 415, the seventh battery cell 416, and the eighth battery cell 417. The third right lead plate 473 is attached across the two right electrodes 42 of the ninth battery cell 418 and the tenth battery cell 419.
In other words, as shown in FIG. 4, the first right lead plate 471 and the second right lead plate 472 are the third battery cell 412 and the fourth battery cell 413, the fifth battery cell 414 and the sixth battery cell 414, respectively. The battery cells 415 are separated from each other so as to be separated and separated from each other. The first right lead plate 471 and the second right lead plate 472 that are adjacent to each other are arranged as lead plates 45 having different potentials. In addition, the second right lead plate 472 and the third right lead plate 473 separate the seventh battery cell 416 and the eighth battery cell 417 from the ninth battery cell 418 and the tenth battery cell 419. In addition, they are arranged apart from each other so as to be electrically disconnected from each other. The second right lead plate 472 and the third right lead plate 473 that are adjacent to each other in the arrangement relationship are lead plates 45 having different potentials. That is, the right lead plates 47 (471, 472, 473) are also adjacent to each other so as to be along the adjacent direction of the electrodes 42 of the ten battery cells 41 arranged in parallel, In addition, the potentials are different from each other.

Next, the case 20 containing the battery pack main body 40 will be described.
The housing case 20 has a function as an outer case of the battery pack 10 and a function as a housing in which the battery pack main body 40 is built. The housing case 20 includes a box-shaped case main body 21 having an upper opening, and an upper lid member 31 that closes the upper opening of the case main body 21 as an upper cover of the case main body 21. The case body 21 and the upper lid member 31 are screwed together by a screw member 39.
First, the upper lid member 31 constituting the housing case 20 will be described.
The upper lid member 31 forms an exterior on the connection side when the battery pack 10 is slid and mounted in the housing case 20. That is, the upper lid member 31 is formed in a structure that can be slidably mounted on a mounting tool such as a tool body. Specifically, a slide guide portion 32 that guides the slide mounting is provided in an intermediate portion of the upper lid member 31. In addition, the upper lid member 31 is provided with a connection opening 33 for connecting the terminal of the wearing tool to the connection terminal portion 53 (connection control board 51) described above. The upper lid member 31 is provided with a hook exposing opening 34 for exposing the hook-shaped structure 56 (male hook mechanism 55) to the outside to be locked with respect to the wearing tool. The upper lid member 31 is provided with a vent hole 35 through which air is sent to cool the inside of the housing case 20. The ventilation port 35 includes a first ventilation port 36 for sending cooling air to the inside of the housing case 20, and a housing after the cooling air sent to the inside of the housing case 20 cools the battery cell 41. And a second vent 37 for exhausting the outside of the case 20. The above-described slide guide portion 32, connection opening portion 33, and the like are formed in a shape corresponding to the slide mounting of the battery pack 10.

Next, the case main body 21 constituting the housing case 20 will be described.
The cross-sectional view of FIG. 5 shows a VV cross-sectional arrow view of the battery pack 10 of FIG. 6 is an enlarged cross-sectional view showing a portion where the drainage hole 25 is disposed (a portion indicated by a chain line in FIG. 5) in the case main body 21 shown in FIG. The top view of FIG. 7 shows the case body 21 as viewed from above with the inside visible. The top view of FIG. 8 shows an enlarged portion of the case main body 21 of FIG. 7 where the drain holes 25 are disposed (a portion with a dashed line in FIG. 5). 5 and 6, the battery pack 10 is placed on a placement surface F that forms a horizontal plane.
As shown in FIG. 1, the case main body 21 is surrounded by one bottom wall portion 211 and four side wall portions 212 so that the above-described battery pack main body 40 can be installed. It has a box shape. The bottom wall portion 211 of the case body 21 corresponds to the bottom portion according to the present invention. As shown in FIG. 5, the case body 21 is formed so that the battery cell 41 described above can be installed. As shown in FIG. 5, the bottom wall portion 211 of the case body 21 has an outer surface 221 formed in a substantially flush shape, while the inner surface 222 is provided with ribs 23 that are appropriately uneven. Has been. The rib 23 is formed so as to protrude into the case main body 21 with an appropriate uneven shape. The ribs 23 are formed of three types: support ribs 231, air guide ribs 232, and foreign matter intrusion restriction ribs 233. As shown in FIG. 5 and FIG. 6, the support rib 231 functions as a rib that supports the battery cell 41 to be installed in order to stabilize the device state of the battery cell 41 that is mainly installed in the case body 21. For this reason, the support rib 231 is formed in the concave curved surface shape corresponding to the outer peripheral curved surface shape of the battery cell 41 to be installed. The support rib 231 also contributes to improving the strength of the case main body 21 itself. Further, as shown in FIG. 6, the air guide rib 232 serves as a guide for guiding the cooling air when the cooling air is sent from the first air outlet 36 to the second air outlet 37 so as to cool the battery cell 41. Function. For this reason, the air guide rib 232 is selected so that the wind sent into the case body 21 can cool the battery cells 41 efficiently. Note that the air guide rib 232 also has a function and the like as a rib for supporting the battery cell 41 to be installed, similar to the support rib 231 described above. The foreign matter intrusion restriction rib 233 will be described after the description of the drain hole 25 described below.

As shown in FIGS. 3 and 4, the case main body 21 is provided with a drain hole 25 having a function of discharging water that has entered the housing case 20 to the outside of the housing case 20. The drain hole 25 is included in the drainage function shape part according to the present invention. The drain hole 25 is disposed so as to communicate the inside and outside of the housing case 20 with respect to the bottom wall portion 211 forming the bottom portion of the housing case 20. The location of the drain holes 25 is set so as to exist between the lead plates 45 connected to the electrodes 42 of the battery cells 41 with respect to the bottom wall portion 211 of the housing case 20. Therefore, as can be seen by comparing FIGS. 3 and 4 with respect to FIG. 2, the drain holes 25 are disposed so as to exist between the four lead plates 45.
Specifically, in the left part of the bottom wall part 211 of the housing case 20, the first drain hole 251 is arranged between the first left lead plate 461 and the second left lead plate 462 described above. The second drain hole 252 is disposed between the second left lead plate 462 and the third left lead plate 463 described above. On the other hand, in the right side portion of the bottom wall portion 211 of the housing case 20, the third drain hole 253 is disposed between the first right lead plate 471 and the second right lead plate 472 described above. A fourth drain hole 254 is disposed between the second right lead plate 472 and the third right lead plate 473 described above.
In other words, the total number of drain holes 25 arranged in the case body 21 is two less than the total number of lead plates 45 and six less than the total number of battery cells 41. It has become. In addition, as shown in FIG. 8, the hole shape of these drain holes 25 is set to a circular shape when viewed from above, and the diameter of the drain holes 25 is 2.5 mm, which is a hole diameter that is not too large. Is set.
In other words, the first drain hole 251 drains water existing between the first left lead plate 461 and the second left lead plate 462, and the second drain hole 252 includes the second left lead plate 462 and the third left lead. The water existing between the plates 463 is drained. The third drain hole 253 drains water existing between the first right lead plate 471 and the second right lead plate 472, and the fourth drain hole 254 includes the second right lead plate 472 and the fourth right lead plate. Drain the water existing between 473 and 473.

Here, each of the drain holes 25 (251, 252, 253, 254) is set as follows and disposed in the bottom wall portion 211 of the housing case 20. The drain hole 25 will be described with reference to FIGS. 6 and 8 which are enlarged views. Of the drainage holes 25, the opening edge of the drainage hole 25 disposed outside the housing case 20 is set as the outer side edge 261, and the drainage hole 25 disposed inside the housing case 20 is The opening edge is set as the inner edge 262. That is, as shown in FIG. 6, the outer side edge 261 of the drain hole 25 (251) is closer to the inside of the case case 20 than the support lower surface 201 of the case case 20 that is the peripheral portion of the outer side edge 261. The shape is set to be slightly raised toward the surface. Therefore, a gap C is formed between the mounting surface F with which the support lower surface 201 of the housing case 20 that is the peripheral portion of the outer side edge 261 contacts and the outer side edge 261. .
Further, a foreign matter intrusion restricting rib 233 is disposed inside the housing case 20. That is, as shown in FIG. 6, in the portion located above the inner side edge 262 of the drain hole 25, the foreign matter is located at a position spaced upward from the inner side edge 262 of the drain hole 25. An intrusion restricting rib 233 is provided. That is, the foreign matter intrusion restricting rib 233 is disposed apart from the inner side edge 262 of the drainage hole 25 while maintaining the open state of the drainage hole 25. Further, as shown in FIG. 8, the foreign matter intrusion restricting rib 233 is disposed so as to cross the opening shape of the drain hole 25 inside the housing case 20.

According to the battery pack 10 configured as described above, the following operational effects can be achieved.
That is, according to the battery pack 10 described above, the location of the drain holes 25 is set so as to exist between the lead plates 45 connected to the electrodes 42 of the battery cells 41. The water between them can be discharged from the inside of the housing case 20 to the outside of the housing case 20. Accordingly, at least water between the lead plates 45 can be drained, and electrical connection due to the lead plates 45 being immersed in water can be prevented. That is, even if appropriate ribs 23 such as the support ribs 231 and the air guide ribs 232 are formed in the housing case 20 so as to support the battery cells 41, at least the lead plate while allowing water to be accumulated by the ribs 23. It is possible to prevent electrical connection due to the 45s being immersed in water. Accordingly, the lead plates 45 are immersed in water, whereby unintended electrical connection between the lead plates 45 can be prevented. That is, water that has entered the housing case 20 can be efficiently drained out of the housing case 20 so as to prevent leakage of electricity stored in the battery cells 41. Further, the drainage holes 25 to be arranged are limited to the minimum number of places where the unintentional electrical connection between the lead plates 45 can be prevented, so the number of drainage holes is kept as small as possible. Can do.
Further, according to the battery pack 10 described above, the lead plates 45 that set the arrangement positions of the drain holes 25 are the lead plates 45 that are adjacent to each other and have different electric potentials, so that there is no water. In this way, the drainage points can be set between the lead plates 45 that are adjacently arranged and have different potentials. As a result, it is possible to set a place where the lead plate 45 is likely to be short-circuited so that the water drainage is maintained and the insulation state is maintained, and the short-circuit caused by the lead boards 45 being immersed in water can be prevented. Can be made more reliable.

Further, according to the battery pack 10 described above, the outer edge 261 of the drain hole 25 disposed outside the casing case 20 has at least the casing lower case 201 than the support lower surface 201 that is the peripheral portion of the outer edge 261. The shape is set so as to rise toward the inside 20. Thus, even when the battery pack 10 attached to a tool main body (not shown) is placed on a desk or the ground and the support lower surface 201 serving as the bottom portion of the battery pack 10 contacts the placement surface F. The outer edge 261 of the drainage hole 25 is positioned so as to be lifted by a gap C from the placement surface F. Therefore, the drain hole 25 can be prevented from being blocked by the placement surface F, and the water that has entered the housing case 20 can be discharged from the drain hole 25 to the outside of the housing case 20. In addition, since a slight gap C can be formed between the outer edge 261 of the drain hole 25 and the placement surface F, the surface tension of the water that has entered the gap C is utilized. The water in the housing case 20 can be easily guided to the outside of the housing case 20. Accordingly, the water that has entered the housing case 20 can be efficiently drained out of the housing case 20.
In addition, according to the battery pack 10 described above, the foreign matter intrusion regulation rib 233 is disposed inside the housing case 20 so as to cross the opening shape of the drain hole 25 inside the housing case 20. Even when foreign matter is likely to enter from the outside to the inside of the housing case 20 through the hole 25, the foreign matter intrusion restricting rib 233 can prevent foreign matter from entering. Thereby, the inside of the housing case 20 can be maintained in a clean state.

Next, two modifications of the battery pack 10 of the first embodiment will be described with reference to FIGS. 9 and 10. FIG. 9 is a cross-sectional view of the battery pack 10 </ b> A showing a modification example in which the drainage path 27 is provided. FIG. 10 is an enlarged top view of the drain hole 25A showing a modified example in which the drawing groove 28 is provided.
The two modified examples shown in FIGS. 9 and 10 are examples in which the positions where the drain holes 25 are arranged are set so as to exist between the lead plates 45 as described above. These two modifications are examples in which the flow guide means or the retracting guide means are arranged at a position different from the position between the lead plates 45 that set the arrangement position of the drain hole 25.
The flow guide means and the retracting guide means are included in the drainage function shape portion according to the present invention. These flow guide means and pull-in guide means are configured by forming the housing case 20 with a shape having a function of discharging water that has entered the housing case 20 to the outside of the housing case 20. It is supposed to be.
In this modification, the configuration of the drainage path 27 as the flow guide means or the configuration of the drawing groove 28 as the drawing guide means is different from the battery pack 10 described above in that it is disposed. For this reason, about the structure except this different structure, it is the same as the battery pack 10 mentioned above. With respect to the parts configured in the same manner as the battery pack 10 described above, the same reference numerals as those described for the battery pack 10 described above, or the same reference numerals with the suffix “A” added to the drawings. Therefore, the description thereof is omitted.
In the modified example described below, the position of the drain hole 25 is set to be between the lead plates 45 as in the case of the battery pack 10 described above. On the other hand, the configuration of the drainage path 27 as the flow guide means or the configuration of the drawing groove 28 as the drawing guide means is set at a position different from the position between the lead plates 45.

First, a modification in which the drainage path 27 is provided in the battery pack 10A will be described. The battery pack 10A shown in FIG. 9 is provided with a drainage path 27 as a flow guide means. The drainage path 27 guides the flow of water so that the water flows toward the drainage hole 25. In other words, the drainage path 27 is formed in the bottom surface 223 that becomes the inner side surface 222 of the housing case 20 in the bottom wall portion 211 of the case body 21. The drainage path 27 is formed so that the bottom surface 223 is inclined downward toward the drainage hole 25. Specifically, the bottom surface 223 located on the lower side of the second left lead plate 462 is formed as a first drainage path 271 in which the front half is inclined downward toward the first drainage hole 251, A side half is formed as a second drainage passage 272 that inclines downward toward the second drainage hole 252. In other words, the bottom surface 223 located below the second left lead plate 462 is formed in a mountain shape having a skirt extending in the front-rear direction, with the lower center of the second left lead plate 462 serving as the top. In addition, a third drainage path 273 is formed on the bottom surface 223 located below the third left lead plate 463 so that the front half is inclined downward toward the second drainage hole 252. In other words, the bottom surface 223 located below the third left lead plate 463 is formed in a half-mountain shape having a bottom at the center of the third left lead plate 463 and having a skirt extending forward. Yes. The bottom wall portion 211 of the case main body 21 is formed in an inclined shape with respect to the bottom surface 223 that becomes the inner side surface 222, and the outer side surface 221 is supported by contacting the mounting surface F described above. Is formed in a flush shape.
According to the battery pack 10A of this modification, in addition to the operational effects achieved by the battery pack 10, the following operational effects can also be achieved. That is, according to the battery pack 10A described above, the drainage path 27 serving as the flow guide means has the bottom surface 223 of the casing case 20 inclined downward toward the drainage hole 25. The water that has entered the inside 20 can flow toward the drain hole 25 by the inclined structure of the drain path 27. Thereby, not only the periphery of the drain hole 25 but also the drainage performance of the portion that becomes the drainage path 27 can be enhanced, and the range in which the drainage performance is desired to be increased can be expanded. Further, according to the battery pack 10A, the water around the drain hole 25 can be guided to the drain hole 25 by the drain path 27 serving as the flow guide means, while the water between the lead plates 45 is drained from the drain hole 25. Therefore, the unintended electrical connection between the lead plates 45 can be reliably prevented.

Next, a modified example in which the lead-in groove 28 is provided in the drain hole 25A will be described.
The drain hole 25A shown in FIG. 10 is provided with a drawing groove 28 as a drawing guide means. The drawing groove 28 guides the drawing of water so that the water gathers toward the drain hole 25A. That is, the drawing groove 28 acts to draw water toward the drain hole 25. That is, the lead-in groove 28 is formed in a concave groove shape so as to extend radially from the inner side edge 262 of the drain hole 25 to the inner side surface 222 of the housing case 20. Specifically, five lead-in grooves 28 having a radially extending concave groove shape are formed around the left side portion of the drain hole 25A formed as described above. The five lead-in grooves 28 are appropriately cut into a shallow groove depth with respect to the peripheral surface, and are formed at appropriate intervals.
According to the drain hole 25A of this modification, in addition to the effects provided by the battery pack 10 described above, the following effects can also be obtained. That is, the retraction groove 28 as the retraction guide means is formed in a concave groove shape so as to extend radially from the inner side edge 262 of the drain hole 25 to the inner side surface 222 of the housing case 20, The water existing around the edge 262 can act to be drawn toward the drain hole 25. As a result, the drainage can be extended to the periphery of the drainage hole 25A so that there is no water between the lead plates 45. Therefore, it is possible to more reliably prevent the electrical connection between the lead plates 45 described above that are immersed in water. Further, according to the battery pack having the drainage hole 25A, the water around the drainage hole 25 can be guided to the drainage hole 25A by the lead-in groove 28 serving as the lead-in guide means. Water can be completely eliminated by the presence of the drain holes 25, and unintended electrical connection between the lead plates 45 can be reliably prevented.

[Second Embodiment]
Next, a second embodiment for carrying out the battery pack according to the present invention will be described with reference to FIGS. 11 and 12. In addition, the perspective view of FIG. 11 is a perspective view which shows the case main body 21B which looked in the state which can see the inside. Moreover, the cross-sectional view of FIG. 12 is a cross-sectional view showing the XII-XII cross-sectional view of the case main body 21B of FIG.
That is, the battery pack of the second embodiment is not shown in the overall view, but only the configuration of the case main body 21 in the battery pack 10 of the first embodiment described above is different. Yes. That is, the battery pack of the second embodiment is different from the modification of the first embodiment described above in that a part of the configuration of the drainage path 27B as the flow guide means is between the lead plates 45. The drain hole 25B is set at a position different from the position between the lead plates 45.
In the second embodiment, the arrangement of the drainage path 27B as the flow guide means and the arrangement of the drainage holes 25B are different from those of the battery pack 10 described above. For this reason, since the configuration excluding this different configuration is configured in the same manner as the battery pack 10 described above, the same reference numerals as those described in the battery pack 10 described above are attached to the drawings to describe the same configuration. Is omitted.

That is, as shown in FIGS. 11 and 12, a drain hole 25B is provided in the bottom wall portion 211 of the case body 21B corresponding to the bottom portion according to the present invention. As shown in the figure, the drain hole 25 </ b> B is provided substantially at the center of the bottom wall portion 211. The drain hole 25 </ b> B has a function of discharging the water that has entered the housing case 20 to the outside of the housing case 20, similarly to the drain hole 25 described above. However, the position of the drain holes 25 of the battery pack 10 of the first embodiment described above is set so as to exist between the lead plates 45, whereas the battery of the second embodiment. The arrangement position of the drainage hole 25B of the pack is set to the left and right intermediate position in the bottom wall portion 211. The drain hole 25 </ b> B is disposed so as to communicate between the inside and outside of the housing case 20, similarly to the drain hole 25 described above. On the other hand, the drainage path 27 </ b> B is formed to extend along the left-right direction of the case main body 21 on the bottom surface 223 that becomes the inner side surface 222 of the housing case 20 in the bottom wall portion 211 of the case main body 21. Specifically, the drainage path 27B has a bottom at the top where the first drainage hole 251 (the virtual rounded portion in FIGS. 11 and 12) of the first embodiment is disposed. The wall portion 211 is formed in a groove shape that is inclined so as to descend toward the drain hole 25 </ b> B provided at the approximate center. In other words, the highest portion of the drainage path 27B is located between the first left lead plate 461 and the second left lead plate 462 (the position where the first drain hole 251 of the first embodiment is disposed). Equivalent to). Further, the lowest part of the drainage path 27B is a place where the drainage hole 25B is disposed.
According to the battery pack of the second embodiment, the position of the drain hole 25B is set at the approximate center of the bottom wall portion 211, and the top portion of the drain path 27B is the first left lead plate 461 and the first portion. 2 is set so as to be located between the left lead plate 462 (corresponding to the position where the first drain hole 251 of the first embodiment is disposed). Thus, the water between the lead plates 45 can be drained from the inside of the housing case 20 to the outside, and the position of the drain holes 25B can be set according to the design of the battery pack. Can be set at the approximate center. Therefore, the freedom degree of the arrangement | positioning position of the drain hole 25B can be raised, and the freedom degree on the design of a battery pack can also be raised.

Note that the battery pack according to the present invention is not limited to the above-described embodiment, and may be configured by appropriately changing the location as follows.
That is, in the above-described embodiment, as an example of the drainage function shape portion, the inclined structure of the drainage passage 27 as the flow guide means and the retracting structure of the retracting groove 28 as the retracting guide means are given. However, the drainage function shape portion according to the present invention is not limited to such an example, and water that has entered the inside of the casing case while having drainage holes communicating between the inside and outside of the casing case. Any shape may be used as long as it has a function of discharging to the outside. For example, various shapes such as an appropriate slope, an appropriate groove, and an appropriate step may be selected. Moreover, as the above-mentioned drainage function shape part which concerns on this invention, you may be comprised only by the drainage hole 25 which connects the inside and outside of the housing | casing case 20 as above mentioned.

DESCRIPTION OF SYMBOLS 10,10A Battery pack 20 Housing | casing case 201 Support lower surface 21,21B Case main body 211 Bottom wall part 212 Side wall part 221 Outer side surface 222 Inner side surface 223 Bottom surface 23 Rib 231 Support rib 232 Air guide rib 233 Foreign object intrusion regulation rib 25, 25A, 25B Drain hole (drainage function shape part)
261 External side edge 262 Internal side edge 27, 27B Drainage path (drainage function shape part, flow guide means)
28 Retraction groove (drainage function shape part, retraction guide means)
31 Upper cover member 32 Slide guide portion 33 Connection opening portion 34 Hook exposure opening portion 35 Ventilation opening 39 Screw member 40 Battery pack body 41 Battery cell 42 Electrode 45 Lead plate 46 (461, 462, 463) Left lead plate 47 (471 , 472, 473) Right side lead plate 51 Connection control board 52 Control board 53 Connection terminal part 55 Male hook mechanism 56 Hook-type structure C Clearance F Mounting surface

Claims (3)

A battery pack configured to be attached to the power tool body as a power source of the power tool,
A housing case forming an exterior, and a plurality of battery cells installed in the housing case,
The bottom wall portion of the housing case is provided with a drain hole that communicates the inside and outside of the housing case.
The outer side edge of the drainage hole is formed in a shape raised toward the inside of the housing case from the lower supporting surface of the housing case, and the outer side edge and the lower supporting surface of the housing case The battery pack has a configuration in which a gap is formed between the housing case and the mounting surface, and water in the housing case can be discharged to the outside through the gap . The battery pack according to claim 1,
A plurality of the drain holes are provided in the bottom wall portion of the housing case. The battery pack according to claim 2,
The bottom wall portion has a rectangular shape in plan view,
The battery pack, wherein the plurality of drain holes are arranged point-symmetrically with respect to a rectangular center of the bottom wall portion.

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