JP2008270007A - Battery pack and electric tool using this - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a battery pack which can make compact an electric tool and improve workability as well. <P>SOLUTION: The battery pack 5 is mounted removably in an handle portion of the electric tool and houses a plurality of battery cells 8A, 8B in a battery case 7, and one battery cell 8A is housed vertically in the battery case 7 and two of battery cells 8B are housed horizontally in a lower side of the vertically arranged battery cell 8A, and both of battery cells 8A, 8B are arranged in an L-shape when viewed from a side. Furthermore, a board 9 is arranged on an upper side of the horizontally arranged battery cells 8B in the battery case 7, and moreover the vertically arranged battery cells are arranged overlapping on the horizontally arranged battery cells 3B in a longitudinal direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a battery pack in which a plurality of battery cells are accommodated in a battery case, and a cordless electric tool that is detachably mounted.

  A battery pack is detachably attached to the cordless hand-held power tool, and the battery pack is configured by accommodating a plurality of battery cells in a battery case.

  By the way, the hand-held power tool is not only lightweight and compact, but also requires a handle shape that fits the hand and is easy to grip and has good workability, because the user directly holds it by hand. . For this reason, two types of battery packs to be mounted on such a hand-held power tool, those shown in FIGS. 6 to 8 and those shown in FIGS. 9 to 11 were used.

  6 is a cutaway side view of the electric tool equipped with the first type of battery pack, FIG. 7 is a side sectional view of the first type of battery pack, and FIG. 8 is a sectional view taken along line BB in FIG. The battery pack 105 is configured with priority given to the shape of the handle portion 102B of the electric power tool 101 shown in FIG.

  In other words, in order to make the handle portion 102B of the electric tool 101 easy to grip, a plurality of (three in the illustrated example) battery cells 108 are stacked and accommodated in the battery case 107 in a horizontal position. The battery pack 105 is detachably attached to the lower end of the handle portion 102B, avoiding the handle portion 102B.

  9 is a cutaway side view of the electric tool equipped with the second type battery pack, FIG. 10 is a side sectional view of the second type battery pack, and FIG. 11 is a sectional view taken along the line CC of FIG. The illustrated battery pack 205 is configured with priority given to the compactness of the electric power tool 201 shown in FIG. 9.

  That is, in order to reduce the size of the electric tool 201, the battery cell 208 includes a handle portion 202B in a battery pack 205 in which a plurality (three in the illustrated example) of battery cells 208 are accommodated vertically in a battery case 207. It is designed to be installed so that it is completely housed inside.

6 and 9, in the electric tools 101 and 201, reference numerals 102 and 202 denote housings, and 103 and 203 denote electric motors that are drive sources incorporated in the body portions 102A and 202A of the housings 102 and 202, respectively. 204 and 204 are output shafts that are rotationally driven by the electric motors 103 and 203, and 106 and 206 are switches for turning ON / OFF the power supply from the battery packs 105 and 205 to the electric motors 103 and 203.
JP 2006-302759 A

  However, when the battery pack 105 of the first type shown in FIGS. 6 to 8 is used, the handle portion 102B of the electric power tool 101 has a small diameter so that it is easy to grip and work, but the entire battery pack 105 is the handle portion. Since it protrudes greatly by the length h ′ shown in the figure from 102B, there is a problem in that the external dimensions of the entire electric power tool 101 become large and the electric power tool 101 cannot be made compact.

  Further, when the second type of battery pack 205 shown in FIGS. 9 to 11 is used, the external size of the electric power tool 201 can be suppressed to a small size, but the handle portion 202B becomes thick and difficult to grip. There was a problem that work could not be performed with good workability.

  Therefore, in the conventional battery packs 105 and 205, it is impossible to achieve both compactness of the power tools 101 and 201 and improvement in workability, and one of them must be sacrificed.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a battery pack capable of achieving both compactness of the electric tool and improvement in workability, and an electric tool using the battery pack.

  In order to achieve the above object, a first aspect of the present invention provides a battery pack that is detachably attached to a handle portion of an electric power tool and that houses a plurality of battery cells in a battery case. The battery cells are housed vertically, and a plurality of battery cells are housed horizontally below the vertically placed battery cells, and both battery cells are arranged in an L shape in a side view. .

  According to a second aspect of the present invention, in the first aspect of the present invention, a substrate is disposed above the horizontal battery cell in the battery case.

  A third aspect of the invention is characterized in that, in the first or second aspect of the invention, the total outer diameter of the horizontally placed battery cells is set smaller than the electric motor diameter of the electric tool.

  The invention according to claim 4 is the invention according to any one of claims 1 to 3, characterized in that the vertically placed battery cells are arranged so as to overlap in the longitudinal direction with respect to the horizontally placed battery cells. And

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the vertically placed battery cell is disposed below the center of gravity of the electric motor of the electric tool.

  The invention according to claim 6 is the invention according to any one of claims 1 to 5, wherein the battery cell is a lithium ion battery.

  According to a seventh aspect of the present invention, in the electric tool comprising an electric motor as a drive source housed in the housing, the battery pack according to any one of the first to sixth aspects is detachably attached to the handle portion of the housing. It is characterized by that.

  According to the first aspect of the present invention, in a state where the battery pack is mounted on the electric tool, one battery cell placed vertically in the battery case is completely stored in the handle portion of the electric tool, and the other side wakes up. The battery cell can be configured to protrude outside the handle portion, so that the handle portion of the electric tool can be reduced in diameter to improve workability, and the amount of protrusion from the handle portion of the battery pack can be minimized. Therefore, it is possible to reduce the size of the electric tool.

  According to the second aspect of the present invention, since the substrate is arranged above the horizontally placed battery cells in the battery case, the substrate can be rationally arranged by effectively using the space in the battery case.

  According to the invention described in claim 3, since the total outer diameter of the horizontally placed battery cells is set smaller than the electric motor diameter of the electric tool, the electric tool is further reduced in size by reducing the width dimension of the electric tool. Thus, the packing space for the electric tool can be kept small and efficient packing can be performed.

  According to the invention described in claim 4, since the vertically arranged battery cells are arranged so as to overlap in the longitudinal direction with respect to the horizontally placed battery cells, the size of the battery pack in the longitudinal direction is reduced to reduce the size of the battery pack. Can be achieved. Moreover, since there is no gap between the battery cells on the bottom surface of the battery case, high strength is ensured in the battery case, and the durability of the battery case is enhanced.

  According to the fifth aspect of the present invention, since the vertically placed battery cells are arranged below the center of gravity of the electric motor of the electric tool, the weight balance of the electric tool is maintained well, and the operability of the electric tool is improved. The improvement of the property is achieved.

  According to the invention described in claim 6, since the lithium ion battery whose rated voltage is about three times that of a nickel metal hydride battery, nickel cadmium or the like is used as the battery cell, the number of battery cells with respect to the required voltage is reduced. The battery pack and the power tool can be reduced in size and size.

  According to the invention described in claim 7, it is possible to achieve both compactness of the electric tool and improvement of workability.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  1 is a cutaway side view of a driver drill as an embodiment of an electric power tool according to the present invention, FIG. 2 is a cutaway front view of the driver drill, FIG. 3 is a side sectional view of a battery pack according to the present invention, and FIG. 3 is a cross-sectional view taken along line AA in FIG.

  A driver drill 1 shown in FIGS. 1 and 2 includes a housing 2 having a T-shape when viewed from the side, and an electric motor 3 as a drive source is accommodated horizontally in a body portion 2A of the housing 2. The rotation of the electric motor 3 is decelerated by a reduction mechanism such as a planetary gear mechanism and transmitted to the output shaft 4, and the output shaft 4 and a tip tool (not shown) attached to the output shaft 4 are rotationally driven to perform screw tightening or the like. Necessary work is done.

  A battery pack 5 according to the present invention is detachably attached to a lower end portion of a handle portion 2B that integrally extends downward from the body portion 2A of the housing 2. A switch 6 for starting / stopping the electric motor 3 by turning ON / OFF the power supply from the battery pack 5 to the electric motor 3 is provided at the base end of the upper front surface of the handle portion 2B.

  Next, details of the configuration of the battery pack 5 according to the present invention will be described with reference to FIGS. 3 and 4.

  The battery pack 5 has a battery case 7 that constitutes an airtight container with an upper case 7A and a lower case 7B made of resin that are divided into two vertically. Here, the lower case 7B is formed in a box shape whose upper surface is open, and as shown in FIG. 4, latches 7a are erected on the left and right side walls, and the battery pack 5 is placed in FIGS. As shown in FIG. 3, when the driver drill 1 is attached to the handle portion 2B, the latch 7a engages with a concave latch receiving portion formed on the inner surface of the handle portion 2B of the driver drill 1, so that the battery pack 5 is removed. It is prevented.

  The upper case 7A functions as a cover for covering the upper surface opening of the lower case 7B, and is inserted into the handle portion 2B of the driver drill 1 shown in FIGS. 1 and 2 from below. The insertion portion 7b is erected integrally.

  Thus, when the battery pack 5 is mounted on the handle portion 2B of the driver drill 1 as shown in FIGS. 1 and 2, the upper case 7A portion of the battery case 7 is inserted into the handle portion 2B, and the lower case 7B portion is Although protruding downward from the handle portion 2B, one battery cell 8A is accommodated vertically in the elongated insertion portion 7b of the upper case 7A inserted into the handle portion 2B, and protrudes downward from the handle portion 2B. In the lower case 7B, two battery cells 8B are accommodated horizontally with the longitudinal direction thereof in the front-rear direction (left-right direction in FIG. 1).

  Here, as shown in FIGS. 2 and 4, the two horizontally placed battery cells 8B are juxtaposed in the width direction (the left-right direction in FIGS. 2 and 4), and the two battery cells 8B are arranged in parallel. One battery cell 8A placed vertically is placed between them. As shown in FIGS. 1 and 3, the vertically placed battery cell 8A is arranged so as to overlap the two horizontally placed battery cells 8B in the longitudinal direction (front-rear direction). The battery cell 8A and the horizontally placed battery cell 8B are arranged in an L shape in side view. In the present embodiment, lithium ion batteries are used for the battery cells 8A and 8B.

  Moreover, as shown in FIGS. 1-3, in the space formed in the battery case 7 above the horizontal battery cell 8B, overcurrent, overdischarge and overcharge of the battery cells 8A and 8B are detected. A substrate 9 on which a protection circuit for interrupting the charge / discharge path is mounted horizontally.

  By the way, the cylindrical battery cells 8A and 8B have the same size, and the total outer diameter d of the lateral battery cells 8B is smaller than the outer diameter D of the electric motor 3, as shown in FIG. It is set (2d <D).

  As shown in FIG. 1, the vertically installed battery cell 8 </ b> A is disposed below the center of gravity G of the electric motor 3 of the driver drill 1.

  Thus, in the battery pack 5 configured as described above, the battery pack 5 is vertically installed in the battery case 7 with the battery pack 5 mounted on the handle portion 2B of the driver drill 1 as shown in FIGS. Since one placed battery cell 8A is completely stored in the handle portion 2B of the driver drill 1, the other two battery cells 8B that wake up sideways can be configured to protrude out of the handle portion 2B. The handle portion 2B of the driver drill 1 is reduced in diameter so that the operator can easily grip the handle portion 2B. For this reason, the operator can work with good workability by grasping the handle portion 2B, can improve workability, and the protrusion amount h of the battery pack 5 from the handle portion 2B (FIG. 1 and FIG. 1). The driver drill 1 can be made compact by minimizing the size of the driver drill 1, and the driver drill 1 can achieve both compactness and improved workability.

In the present embodiment, since the substrate 9 is arranged above the horizontally placed battery cells 8B in the battery case 7, the substrate 9 can be rationally arranged by effectively using the space in the battery case 7. At the same time, the substrate 9 can be stably arranged while being protected from external impacts.
Furthermore, in the present embodiment, as shown in FIG. 2, the total outer diameter d of the lateral battery cells 8B is set to be smaller than the outer diameter D of the electric motor 3 of the driver drill 1 (2d <D). Further, the driver drill 1 can be made more compact by reducing the width dimension of the driver drill 1, and the packing space for the driver drill 1 can be reduced and efficient packing can be performed.

  In addition, since the vertically placed battery cell 8A is disposed so as to overlap the horizontally placed battery cell 8B in the longitudinal direction, the longitudinal dimension L (see FIG. 3) of the battery pack 5 is reduced to reduce the length of the battery pack 5. Miniaturization can be achieved. And since there is no gap between the battery cells 8A and 8B on the bottom surface of the battery case 7, high strength is secured in the battery case 7, and the durability of the battery case 7 is enhanced. As shown in FIG. 5 (a), the vertically placed battery cells 8A and the horizontally placed battery cells 8B can be arranged without overlapping in the longitudinal direction. The direction dimension L ′ becomes longer and the battery pack 5 becomes larger, and a gap between the battery cells 8B exists on the bottom surface of the battery case 7, so that the battery case 7 is liable to crack from the gap. It is not preferable. Further, as shown in FIG. 5B, the size of the battery pack 5 in the vertical direction (longitudinal direction of the battery cell 8A) can be shortened relative to the battery pack shown in FIG. When the battery pack 5 shown in FIG. 3 is longer, the battery pack 5 becomes longer and can be mounted stably.

  Further, in the present embodiment, since the vertically installed battery cells 8A are disposed below the center of gravity G of the electric motor 3 of the driver drill 1, the weight balance of the driver drill 1 is maintained well, and the operability of the driver drill 1 is maintained. As a result, the workability can be further improved.

  In addition, in the present embodiment, as the battery cells 8A and 8B, lithium ion batteries having a rated voltage approximately three times that of nickel hydride batteries and nickel cadmium are used. The number of 8B is small (three in this embodiment), and the battery pack 5 and the driver drill 1 can be reduced in size and size.

  By the way, although the above demonstrated the form which applied this invention with respect to the driver drill and the battery pack with which this was attached, this invention is other arbitrary electric tools other than a driver drill, and the battery pack with which this is attached. The same effect as described above can be obtained by applying to the above.

It is a fracture | rupture side view of the driver drill which concerns on this invention. It is a fracture front view of the driver drill concerning the present invention. It is side sectional drawing of the battery pack which concerns on this invention. FIG. 4 is a sectional view taken along line AA in FIG. 3. (A) is a sectional side view of a battery pack according to another embodiment of the present invention, (b) is a front sectional view of the battery pack. It is a fracture | rupture side view of the electric tool equipped with the conventional 1st type battery pack. It is side sectional drawing of the conventional 1 type battery pack. It is the BB sectional view taken on the line of FIG. It is a fracture | rupture side view of the electric tool equipped with the conventional 2nd type battery pack. It is side sectional drawing of the conventional 2nd type battery pack. It is CC sectional view taken on the line of FIG.

Explanation of symbols

1 Driver drill (electric tool)
2 Housing 2A Housing Body 2B Housing Handle 3 Electric Motor 4 Output Shaft 5 Battery Pack 6 Switch 7 Battery Case 7A Battery Case Upper Case 7B Battery Case Lower Case 7a Battery Case Latch 7b Battery Case Insertion Part 8A Vertical battery cell 8B Horizontal battery cell 9 Substrate d Battery cell outer diameter D Electric motor outer diameter G Electric motor center of gravity

Claims (7)

In a battery pack that is detachably attached to the handle portion of the electric tool and contains a plurality of battery cells in a battery case,
One battery cell is accommodated vertically in the battery case, and a plurality of battery cells are accommodated horizontally below the vertically placed battery cell, and both battery cells are arranged in an L shape in side view. A battery pack characterized by that.   The battery pack according to claim 1, wherein a substrate is disposed above the horizontal battery cell in the battery case.   The battery pack according to claim 1 or 2, wherein a total outer diameter of the horizontally placed battery cells is set smaller than an electric motor diameter of the electric tool.   The battery pack according to any one of claims 1 to 3, wherein the vertically placed battery cells are arranged so as to overlap in the longitudinal direction with respect to the horizontally placed battery cells.   The battery pack according to any one of claims 1 to 4, wherein the vertically placed battery cell is disposed below the center of gravity of the electric motor of the electric tool.   The battery pack according to claim 1, wherein the battery cell is a lithium ion battery.   An electric tool comprising: an electric motor as a drive source housed in a housing; and the battery pack according to claim 1 detachably attached to a handle portion of the housing.

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