Charging device

Abstract

The present invention provides a charging device with reduced noise. The charging device (1) includes: a shell (4) on which a battery pack can be loaded and unloaded; a charging circuit unit (circuit elements mounted on a circuit substrate (20)) for charging the battery pack; a cooling fan (30) for generating wind for cooling the charging circuit unit; a first opening (5) for air intake formed in the shell (4); and a second opening (6) for air exhaust. The wind path from the fan (30) to the second opening (6) is connected by a wind path forming unit (33) that is curved and has a lengthened path. The wind path forming unit (33) is narrowed in the middle to form a positional relationship in which the fan (30) cannot be observed from the second opening (6), thereby preventing the operating sound of the fan (30) from leaking to the outside. The wind path forming unit (33) is formed using the wall surface of the shell (4), the outer wind guide wall (34), and the inner wind guide wall (35).

Description

Technical Field

[0001] The invention relates to a charging device for a battery pack of an electric tool, and is particularly useful for reducing the noise of the charging device. Background Art

[0002] In order to cope with the high capacity of the secondary battery in the battery pack, the previous charging device increased the charging current to ensure the capacity and shorten the charging time. However, if the charging current is increased, a large current flows in the charging circuit in the charging device and the secondary battery in the battery pack, so the temperature of the charging circuit and the secondary battery rises sharply, which may cause the degradation and failure of the secondary battery or the failure of the components forming the charging circuit. In order to solve this problem, it is known that there is a charging device that is provided with a cooling fan that generates cooling air in the charging device, so as to cool the heating elements of the charging circuit and the secondary battery in the battery pack during charging. Patent document 1 discloses a charging device that can change the driving mode of the cooling fan, so that the noise of the cooling fan can be reduced by selecting the off mode or the low noise mode. In addition, Patent document 2 discloses a charging device that can use a cooling fan to cool both the battery pack and the charging circuit.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2005-276733

[0006] Patent Document 2: Japanese Patent Application Publication No. 2015-19535 Summary of the invention

[0007] Problems to be solved by the invention

[0008] In conventional charging devices, a cooling fan is disposed near the wall of the charging device housing, and an opening for cooling air (e.g., an exhaust port) is arranged adjacent to the cooling fan. If the distance from the opening (e.g., the exhaust port) to the cooling fan is short, a thin rod may reach the fan when inserted. Therefore, a two-layer structure having columns of different types is formed in the opening serving as the exhaust port, thereby making it difficult for foreign objects such as thin rods to reach the cooling fan. Fig.10 The structure of the conventional opening portion will be described.

[0009] Fig.103 is a diagram showing the cross-sectional shape of the cooling fan 330 and the exhaust opening 306 of the conventional charging device 301. In the conventional charging device 301, the fan 330 is arranged near the right side wall of the charging device case 302, and air is sucked from the space on the left and passed through the fan 330, and the exhaust of the fan 330 is directly discharged to the outside in a straight line direction. The opening 306 as the exhaust port is formed in a slit shape elongated in the longitudinal direction, and 7 slits are formed here. A parallel wall portion 308 is arranged on the inner side of the right side wall 307 of the charging device case 302, and slits elongated in the vertical direction are formed in the wall portion 308. Furthermore, the columnar portion of the wall portion 308 and the columnar portion of the right side wall 307 of the charging device case 302 do not overlap when viewed in the exhaust direction. Therefore, even if a thin stick is inserted straightly from the right side wall of the charging device case 302 in a direction perpendicular to the wall surface, it will not hit the fan 330, so the risk of foreign matter entering the interior can be reduced. However, if the column of the slit of the opening is set as a two-layer structure, it is difficult to fully ensure the opening area in the limited area 311, and the exhaust airflow is not straight, but is discharged in a curved manner as shown by the black arrow in the figure, which leads to a decrease in air volume. Furthermore, if the fan 330 is set to be close to the opening 306, the noise of the fan 330 is easy to leak directly from the opening 306 to the outside, causing the operating sound of the charging device 301 to become louder.

[0010] In order to solve the noise problem, based on Patent Document 1, the operating sound can be suppressed by reducing the speed of the cooling fan. However, although the noise is reduced, there is also a problem of reduced cooling performance, so it is necessary to design to fully ensure the maximum cooling air volume. Patent Document 2 can only cool both the battery pack and the charging circuit, and does not consider reducing the operating sound generated by the cooling fan.

[0011] The present invention is completed in view of the above background, and its purpose is to provide a charging device with reduced noise. In addition, another purpose of the present invention is to provide a charging device with improved air volume and cooling performance generated by a cooling fan. In addition, another purpose of the present invention is to provide a charging device with a structure that makes it difficult for foreign matter to enter the cooling fan from the opening.

[0012] Technical means of solving problems

[0013] Representative features of the invention disclosed in the present application are described as follows. According to one feature of the present invention, a charging device is formed, including: a case on which a battery pack can be attached and detached; a charging circuit unit housed in the case and charging the battery pack; a fan that generates cooling air for cooling the charging circuit unit; an opening formed in a wall of the case and exhausts the cooling air; and an air path forming portion extending from the downstream side of the fan to the opening and forming a cooling air path for the cooling air to pass between the fan and the opening. The charging device is configured such that a wall of the air path forming portion exists on a virtual straight line connecting an outer edge of the case forming the opening and an end of the fan on a side close to the opening. In addition, the cooling air path is provided on the side or upper side of a substrate on which the charging circuit unit is mounted. In addition, a charging device is formed, wherein the air path forming portion has: a guide portion extending in a lateral direction intersecting with the exhaust direction of the fan and preventing airflow in a direction opposite to the lateral direction; and a duct portion that guides the cooling air guided by the guide portion to the exhaust port in a manner that does not pass through the battery pack.

[0014] According to another feature of the present invention, when the shell of the charging device is divided into four equal parts by the left and right and front and back center lines when viewed from above, the opening (exhaust port) is located in one area of ​​the four-part part, and part or all of the fan is located in an area different from the opening (exhaust port). In addition, when the shell is divided into four equal parts by the left and right and front and back center lines when viewed from above, more than half of the fan is located in one area of ​​the four-part part, and the opening (exhaust port) is located in an area different from the area where more than half of the fan is located. The wind path forming part has: a guide part extending in a lateral direction intersecting with the exhaust direction of the fan and preventing airflow in a direction opposite to the lateral direction; and a duct part that guides the cooling air guided by the guide part to the opening (exhaust port) in a manner that does not pass through the battery pack. In addition, the cooling air path is configured to have: a first area provided on the fan side; and a second area provided on the opening (exhaust port) side continuously with the first area, and the maximum width of the horizontal cross-sectional area of ​​the second area in the flow direction is greater than the maximum width of the first area.

[0015] According to another feature of the present invention, the upper surface of the housing has a battery pack connection portion for mounting the battery pack, and the fan and the cooling air path are located below the battery pack connection portion. The maximum height H of the cooling air path is greater than the maximum width L2 to L4 of the left and right. The housing has: a circuit configuration area, in which the charging circuit portion is configured; and an air path configuration area, in which the cooling air path is configured separately from the circuit configuration area.

[0016] According to another feature of the present invention, the charging device includes: a fan that generates cooling air for cooling the charging circuit unit and is arranged on the downstream side of the charging circuit unit; and an opening (exhaust port) formed in the shell away from the battery pack connection portion to discharge the cooling air to the outside of the shell. An air path forming portion is provided, which connects the exhaust side of the fan to the opening (exhaust port) of the charging device to form a cooling air path for the cooling air to pass through without passing through the battery pack. The opening (exhaust port) is provided on the side of the shell of the charging device, and the air path forming portion is provided along the inner side of the shell. The shell includes: a lower shell that accommodates the charging circuit unit; and an upper shell that is fixed to the lower shell above the lower shell, and the air path forming portion is formed by the upper shell and the lower shell. In addition, the fan is clamped by the upper shell and the lower shell. The shell includes a second opening portion that faces the opening of the battery pack when the battery pack is installed in the shell. The fan generates cooling air for cooling the battery pack through the opening portion, and generates cooling air for cooling the charging circuit unit.

[0017] Effects of the Invention

[0018] According to the present invention, a charging device capable of reducing noise can be provided. In addition, a charging device with improved air volume and cooling performance generated by a cooling fan can be provided. In addition, a charging device with a structure that makes it difficult for foreign matter to enter the cooling fan from the opening can be provided. In addition, since the length of the duct portion is lengthened, the fan and the opening portion (exhaust port) can be set at separate positions, and the sound of the fan can be transmitted to the outside of the shell after being fully attenuated. In addition, since the air path forming portion is configured to be bent so that even if a thin rod is inserted into the inside from the second opening portion, it will not touch the rotating portion of the fan, and the safety quality can be ensured without forming the slit structure of the opening portion into two layers. In addition, since the slit structure of the opening portion is not two layers but one layer, the area of ​​the second opening portion can be ensured, and the air volume and cooling performance can be improved. In addition, since the second opening portion is formed away from the battery pack connection portion, the second opening portion will not be blocked by the battery pack, so the air volume can be suppressed from decreasing. In addition, since the second opening portion is formed on the side, it is difficult for foreign matter such as rainwater to enter the shell from the second opening portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a perspective view of the charging device 1 according to the embodiment of the present invention, and shows a state where a battery pack is installed.

[0020] Figure 2 It is a perspective view of the charging device 1 of this embodiment, and shows a state where a battery pack is not installed.

[0021] Figure 3 yes Figure 1 A three-dimensional diagram of the charging device 1 with the upper shell removed.

[0022] Figure 4 yes Figure 1 A horizontal cross-sectional view of a charging device 1 .

[0023] Figure 5 yes Figure 1 A vertical cross-sectional view of the charging device 1.

[0024] Figure 6 Yes means Figure 4 FIG. 1 is a partially enlarged view of a horizontal cross section of the vicinity of the air passage forming portion 33 of the charging device 1 .

[0025] Figure 7 yes Figure 6 A vertical cross-sectional view of the AA portion of the charging device 1.

[0026] Figure 8 FIG. 1 is a horizontal cross-sectional view of a charging device 101 according to a second embodiment of the present invention.

[0027] Fig. 9 FIG. 2 is a horizontal cross-sectional view of a charging device 201 according to a third embodiment of the present invention.

[0028] Fig.10 It is a partial horizontal cross-sectional view of the vicinity of the opening of a charging device 301 according to a conventional technology example.

[0029] [Explanation of Symbols]

[0030] 1: Charging device

[0031] 2: Charging device shell

[0032] 2a: Anterior wall

[0033] 2b: Right wall

[0034] 3: Upper shell

[0035] 4: Lower shell

[0036] 5: First opening

[0037] 6: Second opening

[0038] 6a: Right side of the second opening

[0039] 6b: Second opening front side

[0040] 7: The third opening

[0041] 8a, 8b: Concave group

[0042] 9: Cooling room

[0043] 10: Battery pack connection

[0044] 11a, 11b: Feet

[0045] 13a, 13b: Choke coil

[0046] 14: Capacitor

[0047] 15: Transformer

[0048] 16a~16c:Diode

[0049] 17: FET

[0050] 18, 19: Cooling fins

[0051] 18a, 19a: left wall

[0052] 18b, 19b: rear wall

[0053] 19c: incision

[0054] 20: Circuit board

[0055] 21: Catheter

[0056] 22a~22d, 23d: threaded boss

[0057] 24: USB socket

[0058] 24a: Cover

[0059] 25: Front room (of the fan)

[0060] 28: Display unit

[0061] 30: Fan

[0062] 33: Air path forming part

[0063] 34: Outer wind guide wall

[0064] 35: Inner wind guide wall

[0065] 36: Guide section (first area)

[0066] 37: Catheter section (second area)

[0067] 37a: Connection passage

[0068] 37b: Exhaust port configuration room

[0069] 38: Space

[0070] 41a, 41b: Guide rail

[0071] 42: Connection terminal

[0072] 60: Battery Pack

[0073] 61: Battery pack shell

[0074] 62: Latch button

[0075] 64: Suction port

[0076] 101: Charging device

[0077] 104: Lower shell

[0078] 104a: Right side wall

[0079] 119: Cooling fins

[0080] 119b: Back wall

[0081] 125: Front room (of the fan)

[0082] 130, 131: Fan

[0083] 133: Air path forming part

[0084] 134: Outer wind guide wall

[0085] 135: Inner wind guide wall

[0086] 201: Charging device

[0087] 204: Lower shell

[0088] 206: Opening

[0089] 220: Circuit board

[0090] 230: Fan

[0091] 233: Air path forming part

[0092] 235: Inner wind guide wall

[0093] 301: Charging device

[0094] 302: Charging device shell

[0095] 306: Opening

[0096] 307: Right side wall

[0097] 308: Wall

[0098] 311: Area

[0099] 330: Fan

[0100] AF1~AF3: Cooling air

[0101] EX1: Exhaust air DETAILED DESCRIPTION

[0102] Example 1

[0103] Hereinafter, embodiments of the present invention will be described based on the accompanying drawings. In the following drawings, the same reference numerals are attached to the same parts, and repeated descriptions are omitted. In addition, in this specification, the directions of front, back, left, right, up and down are set as the directions shown in the drawings for description.

[0104] The charging device 1 is a device for charging a battery pack 60 removed from an electric device such as an electric tool using a commercial power source. The charging device housing 2 as the housing of the charging device 1 has an upper housing 3 (upper housing) and a lower housing 4 (lower housing), and is in the form of a substantially rectangular parallelepiped that is long in the left-right direction. The upper housing 3 and the lower housing 4 are made of a heat-resistant resin material having electrical insulation properties and are formed by injection molding. In addition, in this specification, the term "charging device" is used interchangeably with the term "charging device". Figure 1 The direction between the upper shell 3 and the lower shell 4 is defined as the up-down direction, the length directions of the upper shell 3 and the lower shell 4 are defined as the left-right direction, and the direction orthogonal to these directions is defined as the front-back direction.

[0105] The upper shell 3 forms the upper half of the charging device shell 2, and a battery pack connection portion 10 is provided in the right area of ​​the upper surface thereof (see Figure 2 ), a display unit 28 is provided in the left area. The display unit 28 is provided with a battery capacity indicator of the battery pack 60, an indicator light of the charging status, a temperature abnormality warning light, a power supply switch to the universal serial bus (USB) output terminal, and the like. A slit-like recess group 8a and a recess group 8b are formed at the corners in the front-back direction of the display unit 28, spanning from the front surface to the upper surface, and spanning from the rear surface to the upper surface. The recess group 8a and the recess group 8b are provided to improve the strength and from the viewpoint of design, and are not through holes for communicating air inside and outside the upper shell 3. A first opening 5 is formed near the lower center of the front side wall 2a of the charging device shell 2, and a second opening 6 is formed from the vicinity of the right corner of the front side wall 2a to the vicinity of the front corner of the right side wall 2b. One of the first opening 5 and the second opening 6 is used as an air intake port, and the other is used as an air exhaust port. In the present embodiment, the first opening 5 is used as an air intake port and the second opening 6 is used as an air exhaust port. However, conversely, the second opening 6 may be used as a suction side.

[0106] The first opening 5 is a long hole extending from the front side to the bottom of the lower shell 4 in the vertical direction, and a plurality of openings (13) are arranged in the left-right direction to introduce the outside air into the charging device shell 2. The first opening 5 is formed only by the lower shell 4, but the second opening 6 is provided by both the upper shell 3 and the lower shell 4. The upper part of the second opening 6 serving as an outlet for cooling air is formed at the right front corner of the upper shell 3. The upper part of the second opening 6 is a slit-shaped opening elongated in the vertical direction formed during the injection molding of the upper shell 3, and a plurality of openings are provided.

[0107] The lower shell 4 forms the lower half of the charging device shell 2. The first opening 5 is formed by a plurality of slits elongated in the longitudinal direction, and the lower part of the second opening 6 is formed in a position parallel to the upper part in the left-right direction and the front-back direction. Figure 1 It can be understood that the first opening 5 as the air intake port is expanded in the lateral direction to ensure a certain degree of opening area, but the second opening 6 is arranged in the longitudinal direction, thereby efficiently utilizing the side wall portion of the charging device case 2 from the bottom surface to the top surface of the inner space.

[0108] The battery pack 60 includes a battery pack case 61, a secondary battery (not shown) housed in the battery pack case 61, and a battery-side terminal portion (not shown) connected to the secondary battery and connected to the connection terminal portion of the charging device 1. The battery pack 60 charges the secondary battery (not shown) housed in the battery pack case 61 by being connected to the charging device 1. The type of the secondary battery is arbitrary, but when a lithium-ion battery is used, the output voltage is, for example, 14.4 V for 4 cells, 18 V for 5 cells, and 36 V for 10 cells.

[0109] The battery pack case 61 is a substantially rectangular parallelepiped, and has an air inlet 64 formed on its front surface for introducing outside air into the battery pack case 61. Figure 1 The battery pack housing 61 is provided with a connection terminal portion (not shown in the figure) on the upper surface thereof, which is installed in an inverted state on the charging device 1. An exhaust port (equivalent to the opening of the battery pack, not shown in the figure) for exhausting the outside air introduced from the suction port 64 is formed on the upper surface of the battery pack housing 61.

[0110] Figure 2 is from Figure 1 A three-dimensional view of the state after the battery pack 60 is removed from the battery pack 60. The battery pack connection portion 10 is arranged on the right side of the upper surface of the upper shell 3, and the battery pack 60 can be installed here. Near the center of the battery pack connection portion 10, a third opening portion 7 (connection portion opening) is formed as a suction port, which sucks air from the battery pack 60 side through the exhaust port (not shown) of the battery pack 60. The third opening portion 7 is a slit-shaped long hole extending in the front-to-back direction, and 6 of them are arranged in the left-to-right direction. The shape of the third opening portion 7 is generally consistent with the shape of the exhaust port (not shown) formed on the battery pack 60 side. Guide rail portions 41a and guide rail portions 41b extending parallel to the front-to-back direction are formed on the left and right sides of the battery pack connection portion 10. A connection terminal portion 42 connected to the battery side terminal of the battery pack 60 is provided in the portion clamped by the guide rail portions 41a and the guide rail portions 41b. The battery pack 60 can be slid horizontally from the rear to the front side in an inverted state, as shown in FIG. Figure 1When the battery pack 60 is connected to the battery pack connection portion 10, the third opening 7 is close to and faces the discharge port (not shown) of the battery pack 60. Therefore, if air is sucked from the third opening 7, it has the same effect as sucking air from the inside of the battery pack 60. When the battery pack 60 is removed from the charging device 1, Figure 1 While pressing the latch buttons 62 on both sides (refer to Figure 1 ), or by sliding the battery pack 60 horizontally backward without pressing the latch button 62, the battery pack 60 can be removed from the battery pack connecting portion 10.

[0111] When the battery pack 60 and the charging device 1 are connected at the battery pack connection portion 10, the connection terminal portion 42 is engaged with the battery-side terminal (not shown) of the battery pack 60, so that the battery pack 60 and the charging device 1 are electrically connected. The connection terminal portion 42 is provided with five terminals, namely, a + terminal for charging, a - terminal, an LD terminal, a T terminal, and an LS terminal. In addition, a signal terminal other than the above-mentioned terminals may be provided in the connection terminal portion 42, as long as the connection terminal portion 42 is appropriately set in accordance with the battery pack 60 to be connected.

[0112] The rail portions 41a and 41b are respectively provided on the left and right sides of the connection terminal portion 42 in a manner extending in the front-rear direction, and when the battery pack 60 and the charging device 1 are connected at the battery pack connection portion 10, the slide groove (not shown) of the battery pack 60 slides along the rail portions 41a and 41b, thereby guiding the connection between the battery-side terminals of the battery pack 60 and the connection terminal portion 42 of the charging device 1. In addition, after this connection, the battery pack 60 is stably held by the slide groove and the rail portions 41a and 41b.

[0113] Figure 3 This is a three-dimensional view of the charging device 1 in a state where the upper shell 3 is removed. The upper shell 3 and the lower shell 4 are fixed by a plurality of screws after accommodating electrical components and a cooling fan, etc. inside. The lower shell 4 forms the lower half of the charging device shell 2, and a first opening 5 for sucking in external air and a lower portion of a second opening 6 (6a, 6b) are formed on the side wall. The first opening 5 and the second opening 6 are formed when the synthetic resin is molded, and threaded bosses 22a to 22d are formed near the four corners of the lower shell 4, and the threaded bosses 22a to 22d have through holes for screws to penetrate from the bottom. A USB socket 24 is provided on the left side of the second opening 6 of the lower shell 4 and between the first opening 5, and a rubber cover 24a that can be opened and closed is provided on the installation port of the USB socket 24.

[0114] Most of the charging circuit section constituting the charging device 1 is mounted on a circuit board 20. The circuit board 20 is a single-layer or multi-layer printed circuit board, and after various electronic components are fixed by welding or the like, they are fixed to the lower case 4 by a plurality of screws (not shown). The circuit board 20 is mounted with a choke coil 13a, a choke coil 13b, a capacitor 14, a transformer 15, three diodes 16a to 16c, and a field effect transistor (FET) 17. The heat dissipation section on the back of the diode 16c and the FET 17 is fixed so as to be in contact with the aluminum cooling fin 18, and the high heat dissipation is maintained by the cooling fin 18. In addition, the heat dissipation section on the back of the diode 16a and the diode 16b is also fixed to another cooling fin 19. The cooling fin 18 and the cooling fin 19 not only play a cooling function, but also play a function as a guide for guiding the cooling wind flowing in the charging circuit section to a predetermined direction, that is, the suction side of the fan 30. The choke coil 13b and the capacitor 14 are arranged on the left side of the cooling fin 18. Here, the components that generate large amounts of heat (such as the diodes 16a to 16c, the FET 17, and the transformer 15) are arranged near the first opening 5 and directly exposed to the cooling air path surrounded by the two cooling fins 18 and 19. Another choke coil 13a is provided on the front side of the right side of the cooling fin 19.

[0115] A cooling fan 30 is provided on the right side of the rear portion of the cooling fin 19. The fan 30 is schematically shown in a square box in the figure, but as the fan 30, for example, a fan widely available on the market, called a direct current (DC) fan or a cooling fan, is used. The fan 30 is clamped by an upper shell 3 and a lower shell 4. The fan 30 is used for the purpose of extending the life of electronic components by cooling the heat generated by electronic equipment through air and dissipating the heat. It is housed in a flat rectangular shell made of synthetic resin, and one side of the axial direction is the suction side, and the opposite side is the exhaust side. Here, the fan 30 is arranged in such a way that the left side in the direction of the axis B1 of the fan 30 is the suction side (upstream side) and the right side is the exhaust side (downstream side). The air flowing into the charging device case 2 through the first opening 5 passes through the air path forming portion 33 after passing through the fan 30, and is discharged to the outside of the charging device case 2 through the second opening 6.

[0116] A wind path forming portion 33 is formed on the downstream side of the fan 30 as a passage for exhausting air, and extends from the downstream side of the fan 30 to the second opening 6 formed in the wall of the shell 2. The lower space of the wind path forming portion 33 relative to the dividing horizontal plane becomes an air passage (wind path) defined by the outer wind guide wall 34, the inner wall surface and bottom surface of the lower shell 4, and the inner wind guide wall 35 and reaches the second opening 6. The upper space of the wind path forming portion 33, which is not shown in the figure, is formed on the upper shell 3 (refer to FIG. Figure 2 ) on the inner side. Its shape is the same as the horizontal cross-sectional shape of the charging device shell 2, and wall portions corresponding to the outer wind guide wall 34 and the inner wind guide wall 35 are formed on the upper shell 3. The bottom surface of the air path forming portion 33 is defined by the lower shell 4, and the top surface is defined by the upper shell 3. At the four corners on the lower surface side of the upper shell 3, threaded bosses not shown are formed in a manner protruding downward. The threaded boss not shown is formed integrally with the upper shell 3, and an internal threaded hole corresponding to the threaded boss 22a to the threaded boss 22d with a through hole of the lower shell 4 is formed, and the upper shell 3 and the lower shell 4 are screwed together using screws not shown. In addition, the fixing method of the upper shell 3 and the lower shell 4 is arbitrary, and in addition to the method of using screws, they can also be fixed using known fixing members.

[0117] The outside air sucked from the first opening 5 in the direction of the arrow mainly flows between the cooling fins 18 and the cooling fins 19, and its airflow is bent about 90 degrees from the suction direction by the rear wall surface 18b of the cooling fins 18, and flows toward the cutout portion 19c of the cooling fins 19. The air after passing through the cutout portion 19c flows into the front chamber 25 of the fan 30. The cooling fin 19 is an aluminum plate bent into an L shape, and has a left wall surface 19a and a rear wall surface 19b. The upper ends of the cooling fins 18 and the cooling fins 19 are formed to extend to a position that abuts or is close to the top surface of the upper shell 3. The cooling fins 18 and the cooling fins 19 are fixed to the circuit substrate 20 using a resin such as silicone while being placed on the circuit substrate 20.

[0118] The circuit board 20 is connected to a connection line (not shown) for electrically connecting to the battery pack 60. The circuit board 20 adjusts and controls the charging current, charging voltage, etc. according to predetermined conditions when charging the battery pack 60, thereby safely and quickly charging the battery pack 60. In addition, although not shown here, a microcomputer is mounted on the circuit board 20, so that the charging operation of the battery pack 60 is highly controlled, for example, the battery cell temperature is monitored and the charging current is adjusted according to the battery cell temperature.

[0119] Figure 4 yes Figure 1A horizontal cross-sectional view of the charging device 1. Here, the center line X1 in the front-to-back direction and the center line X2 in the left-to-right direction when the charging device shell 2 is viewed from above are illustrated. In a case where the charging device shell 2 is divided into four equal parts by the center line X1 and the center line X2 to define four areas, the second opening portion 6 serving as an exhaust port for cooling air is located in one area (lower right area) of the four-part part, and at least half or all of the fan 30 is located in an area (upper right area) where the axis B1 of the fan 30 is different from the exhaust port. The cooling air that passes through the fan 30 from the front chamber 25 of the fan 30 in the direction of the arrow flows toward the front side in the narrow width portion in the left-to-right direction of the air path forming portion 33, and a portion of the discharged cooling air is discharged to the right from the right side surface 6a of the second opening portion, and the rest is discharged to the front side from the front side surface 6b of the second opening portion.

[0120] Figure 5 yes Figure 1 A vertical cross-sectional view of the charging device 1 passing through the axis B1 of the fan 30. The fan 30 is formed to be a fan 30 of the maximum diameter that can be accommodated from the bottom surface to the top surface in the internal space below the battery pack connection portion 10 of the charging device shell 2. The circuit substrate 20 is held in a state of floating from the bottom surface of the lower shell 4 by ribs provided in a manner extending upward from the bottom surface of the lower shell 4, and the cooling chamber 9 where the cooling air flows becomes the upper space of the circuit substrate 20. Legs 11a to 11d (11c and 11d are not shown in the figure) are formed at the four corners of the bottom surface of the lower shell 4, and are configured so that when the charging device 1 is placed, the bottom surface of the lower shell 4 is separated from the placement surface by a predetermined distance. In addition, the fan 30 and the cooling air path (air path forming portion 33) are arranged below the battery pack connection portion 10. By optimally arranging the fan 30 and the cooling air path, the enlargement of the charging device 1 can be suppressed.

[0121] The air passing through the fan 30 flows from the front chamber 25 on the left side to the air path forming portion 33 on the right side. In the front chamber 25, which is the inlet side space of the fan 30, the cooling air AF1 flows in through the cutout portion 19c of the cooling fin 19, and the cooling air AF2 that reaches the front chamber 25 through the right side portion of the cooling fin 19 and the cooling air AF3 that flows in from the exhaust port of the battery pack 60 through the third opening portion 7 are guided by the duct 21 and flow into the fan 30. That is, the air (cooling air AF1, cooling air AF2) that is sucked in from the first opening portion 5 and flows into the fan 30 through the front chamber 25 and the cooling air AF3 from the inside of the battery pack 60 that flows into the fan 30 from the third opening portion 7 through the duct 21 are sucked into the fan 30. Since the duct 21 is located on the upper side of the circuit substrate 20 when the upper shell 3 is fixed to the lower shell 4, the battery cooling air path (AF3) and the circuit cooling air path (AF1, AF2) are independent of each other. In this way, the first opening portion 5 (refer to Figure 2) and the third opening 7 form an inlet for air drawn into the charging device 1. The cooling air AF1 to the cooling air AF3 sucked by the fan 30 are mixed (joined) in the fan 30 and discharged from the air passage forming portion 33 side as exhaust air EX1.

[0122] When the battery pack 60 is charged, the outside air introduced into the internal space of the battery pack 60 from the suction port 64 reaches the discharge port (not shown) of the battery pack 60 and passes through the discharge port and the third opening 7 (see FIG. Figure 2 ) and is sucked into the interior of the charging device housing 2. Figure 1 ) to the discharge port, the secondary battery and circuit components inside the battery pack case 61 are cooled. The discharge port of the battery pack case 61 (not shown in the figure) is positioned so as to be aligned with the third opening 7 (see FIG. 1 ) of the charging device 1 when the battery pack 60 is installed in the charging device 1. Figure 2 ) is adjacent to the battery pack casing 61 , so that the air inside the battery pack casing 61 can be sucked into the interior of the charging device casing 2 by the cooling fan on the charging device 1 side.

[0123] Figure 6 Yes means Figure 4 The horizontal cross-section of the charger 1 near the air path forming part 33 is a partially enlarged view. The horizontal cross-section position is near the dividing surface between the upper shell 3 and the lower shell 4. The wind flowing in the air path forming part 33 is separated by the inner air guide wall 35 so that it does not mix with the wind flowing in the cooling chamber 9. The air path forming part 33 is a space elongated in the longitudinal direction (front-to-back direction), connecting the exhaust side of the fan 30 with the second opening 6 as the exhaust port, forming a cooling air path for the cooling wind to pass through without passing through the battery pack 60. In this way, the distance L2 occupied by the air path forming part 33 is shorter than the axial length L1 of the fan 30, so compared with the structure in which the fan 30 is arranged adjacent to the right side wall 2b, the structure of the present invention can be realized without excessively sacrificing space. When viewed from the front side of the fan 30, the inner air guide wall 35 becomes a U-shaped wall, and is connected to the threaded boss 22a at the front side to reach the front side wall of the lower shell 4. That is, the air in the space (cooling chamber 9 ) where the choke coil 13 a and the USB socket 24 are arranged cannot flow to the air path forming portion 33 unless the air passes through the fan 30 .

[0124] The air path forming portion 33 includes: a guide portion 36, which is located within the projection range of the fan 30 when viewed in the direction of the axis B1; and a duct portion 37, which is continuous from the guide portion 36 in a manner extending in a direction perpendicular to the axis B1. The fan 30 is arranged at a distance L2 from the right side wall 2b of the lower shell 4. Here, if the length of the fan 30 in the direction of the axis B1 is set to L1, the relationship L2≦L1 is set. The distance L2 of the guide portion 36 is ensured in this way in order to make the air path bend 90 degrees when viewed from above. The duct portion 37 is an air path extending toward the second opening portion 6. The connecting passage portion 37a of the duct portion 37 adjacent to the guide portion 36 is a portion in which the width L3 in the left-right direction is narrower than the width L2. On the other hand, with respect to the height H3 (at Figure 7 ), the entirety of the connection passage 37a from the top surface of the upper shell 3 to the bottom surface of the lower shell 4 is utilized, so that the connection passage portion 37a is slender in the vertical direction, but a sufficient cross-sectional area can be ensured. A portion of the charging circuit can be arranged to the left of the inner air guide wall 35 that is formed in a U shape when viewed from above, thereby suppressing the reduction in the effective utilization area of ​​the circuit substrate 20. In this way, by reducing the width of the connection passage portion 37a in the left-right direction, the sound generated by the fan 30 can be effectively suppressed from being transmitted to the outside through the second opening portion 6. In this embodiment, by configuring the fan 30 to be sufficiently far away from the second opening portion 6 on the flow path, Fig.10 Compared with the length from the fan 330 to the exhaust port of the conventional charging device shown in FIG.

[0125] In the air path forming portion 33, an exhaust port configuration chamber 37b is formed on the downstream side of the connecting passage portion 37a, in contact with the portion forming the second opening portion 6. The exhaust port configuration chamber 37b is a space in which a slit-shaped exhaust port (second opening portion 6) is configured on the wall surface of the charging device shell 2. In order to ensure the space 38 of the exhaust port configuration chamber 37b, the threaded boss 22a is slightly offset to the left from the ideal configuration position. The right side surface 6a of the second opening portion 6 is formed on the right side side portion of the charging device shell 2, and the front side surface 6b of the second opening portion 6 is formed on the front side portion of the charging device shell 2. The right side surface 6a of the second opening portion 6 is three slits elongated in the longitudinal direction. In addition, the front side surface 6b of the second opening portion 6 is four slits elongated in the longitudinal direction (up and down direction). In the exhaust port configuration chamber 37b, the cooling air flowing in the direction of the axis C1 passes through the slit-shaped opening and is discharged to the outside. In order to effectively disperse the cooling air into the slit portions of the second opening 6 and discharge it, and in order to reduce the exhaust resistance, a predetermined space 38 is ensured in the form of an exhaust port configuration chamber 37b. The maximum width L4 of the space 38 when viewed in the left-right direction is larger than the width L3 of the connecting passage portion 37a and the width L2 of the guide portion 36. The cooling air path defined by the air path forming portion 33 includes: a first area (guide portion 36) provided on the fan 30 side; and a second area (duct portion 37) provided continuously with the first area on the exhaust port (second opening 6) side, and the maximum width L4 of the flow direction cross-sectional area of ​​the duct portion 37 as the second area is larger than the maximum width L2 of the first area.

[0126] The air discharged from the fan 30 flows in the guide portion 36 in a direction parallel to the axis B1 direction. However, in the duct portion 37, the cooling air flows in parallel to the center line C1. Therefore, an outer air guide wall 34 is provided on the outer peripheral side of the curved direction of the flow path of the guide portion 36, and the shape of the outer air guide wall 34 is curved, thereby guiding the air flowing out of the fan 30 in the flow path direction (axis C1 direction) of the duct portion 37. The length in the front-to-back direction of the portion (connection passage portion 37a) where the width of the left and right of the duct portion 37 is reduced is set to a length substantially equal to or greater than the diameter of the opening (not shown) on the exhaust side of the fan 30. In this way, by ensuring the length of the connection passage portion 37a in the duct portion 37 in the axis C1 direction to a certain extent, the operating sound of the fan 30 can be suppressed from leaking to the outside from the second opening portion 6. In addition, by configuring not only the guide portion 36 but also the duct portion 37, it is possible to suppress foreign matter from entering the fan 30 from the second opening portion 6. In particular, a part of the fan 30 cannot be directly seen through the right side 6a of the second opening 6 and the front side 6b of the second opening 6, so no matter which direction a thin stick that can pass through the slit-shaped opening of the second opening 6 is inserted straightly from the second opening 6, it will hit any of the walls (the inner air guide wall 35, the outer air guide wall 34, or the inner wall of the charging device case 2) and will not reach the fan 30. That is, no matter how many virtual straight lines are drawn to connect the outer edge of the charging device case 2 forming the opening and the end of the fan 30 on the side close to the opening, the wall of the air path forming portion 33 exists on all the virtual straight lines.

[0127] Figure 7 yes Figure 6 A vertical cross-sectional view of the AA portion of the charging device 1. Figure 7 As can be understood from the cross-sectional view, the inner air guide wall 35 is formed by aligning the upper portion of the dividing surface extending from the upper shell 3 to the downward direction with the lower portion of the dividing surface extending from the lower shell 4 to the upward direction. In this way, the inner air guide wall 35 is formed to extend in the same direction as the dividing direction (upper and lower directions) during injection molding of the upper shell 3 and the lower shell 4, and the upper shell 3 and the lower shell 4 can be manufactured by the same manufacturing process as before. That is, the outer edge of the air duct forming portion 33 is defined by the right side wall surface 2a, the top surface, and the bottom surface of the upper shell 3 and the lower shell 4. In addition, a portion of the air duct forming portion 33 extends to a position lower than the circuit substrate 20. The air duct forming portion 33 is provided on the side of the circuit substrate 20 (at Figure 7 On the other hand, the air duct forming portion 33 is not disposed in the area directly below the circuit substrate 20 (the area between the circuit substrate 20 and the bottom surface of the lower case 4 in the vertical direction). That is, according to Figure 4 , Figure 5 etc., the area ( Figure 4 The circuit arrangement area (shown by the dotted line of the cooling chamber 9) and the area where the air path forming section 33 is arranged (air path arrangement area) are offset in the left-right direction so as not to overlap in the up-down direction. Thus, the size in the up-down direction can be suppressed. The width L3 of the connecting passage portion 37a in the air path forming section 33 is relatively Figure 6 Although the width L2 and the width L4 shown are formed narrow (thin), the height H3 in the up-down direction is ensured to be maximum, so that the cooling air can be discharged efficiently without increasing the exhaust resistance.

[0128] As described above, in this embodiment, the air path forming portion 33 is arranged on the downstream side of the fan 30 and the length of the air path of the air path forming portion 33 is lengthened, so that noise can be suppressed. The driving sound of the fan 30 can be greatly suppressed from leaking to the outside of the charging device case 2, and as a result, the operating sound of the fan 30 of the charging device 1 can be reduced through the second opening portion 6. Furthermore, since the width of the middle part of the air path forming portion 33 is reduced, the driving sound of the fan 30 can be further suppressed from leaking to the outside of the charging device case 2, and as a result, the operating sound of the fan 30 of the charging device 1 can be reduced through the second opening portion 6.

[0129] The sound of the fan 30 transmitted to the outside through the first opening 5 on the suction side is not zero. However, the first opening 5 is mainly arranged after the charging device 1 is divided into four equal parts. Figure 4 , and extends to the lower right area. However, the lower left area and the lower right area are different from the main configuration area (upper right area) of the fan 30, so the length of the suction flow path is sufficiently longer than the exhaust flow path, so the sound of the fan 30 leaking to the outside through the first opening 5 from the suction side is sufficiently small. In addition, on the suction side of the fan 30, there is a wall portion formed by aluminum cooling fins 19 that is L-shaped when viewed from above, so the transmission of the operating sound from the fan through the first opening 5 is further reduced.

[0130] Example 2

[0131] Figure 81 is a horizontal cross-sectional view of a charging device 101 according to a second embodiment of the present invention. In the second embodiment, in order to increase the air volume within a limited height range, two fans 130 and 131 are arranged in a horizontal direction (front-rear direction). As shown by the arrow in the figure, the air intake of the fan 130 is from left to right, and the exhaust is discharged along the axis B2 direction on the right side of the fan 130. In addition, as shown by the arrow, the air intake direction of the fan 131 is also from left to right, and the exhaust is discharged along the axis B3 direction on the right side of the fan 131. The exhaust wind discharged from the fans 130 and 131 is guided by the outer wind guide wall 134 and the right side wall 104a of the lower shell 104, flows toward the front side in the direction of the arrow 139 inside the wind path forming part 133, and is discharged to the outside from the second opening 6 at the front right corner of the charging device shell. Here, the two fans 130 and 131 are substantially contained in the rear right space of the device shell. A portion of the fan 131 protrudes slightly forward of the center line X1, but the portion that discharges cooling air is approximately rearward of the center line X1. Therefore, the exhaust air in the direction of arrow 139 flowing in the air path forming portion 133 passes through more than half of the front-to-back length of the charging device case, and a sufficient duct length can be ensured before being discharged in the device case. Therefore, the transmission of noise accompanying the rotation of the fan 130 and the fan 131 to the outside can be greatly suppressed.

[0132] The internal shape of the air path forming portion 133 of the upper shell is also substantially the same as that of the lower shell 104, and defines the space of the upper half of the air path forming portion 133. In the upper shell, the air flowing in from the discharge port of the battery pack 60 through the third opening 7 flows into the front chamber 125 as the suction side of the fan 131, and is mainly sucked by the fan 131. On the other hand, most of the air on the fan 130 side flows from the left side to the right side behind the rear wall surface 119b of the cooling fin 119 bent in an L shape, and mainly flows into the fan 130. The configuration of the space on the left side of the center line X2 in the internal space of the charging device 101 is the same as that of the charging device 1 of the first embodiment. On the other hand, the cooling fin 119 is configured such that the left and right lengths of the rear wall surface 119b are shorter than those of the cooling fin 19 of the first embodiment, so that the air flows toward the fan 130 on the rear side of the rear wall surface 119b.

[0133] Example 3

[0134] Fig. 9It is a horizontal cross-sectional view of a charging device 201 according to a third embodiment of the present invention. In the charging device 201, the fan 230 used is set to be one, and the direction of its axis B4 is set to be toward the front side. In addition, the air path forming portion 233 is set to be the same as the width W of the fan 230 in the left-right direction, ensuring the length L5 of the air path forming portion 233. The right side of the air path forming portion 233 is defined by the right side wall of the upper shell and the lower shell 204, and the left side is defined by the inner side wind guide wall 235 formed integrally with the upper shell and the lower shell 204. The upper side of the air path forming portion 233 is defined by the upper wall surface of the upper shell (not shown), and the lower side of the air path forming portion 233 is defined by the upper wall surface of the lower shell 204 (not shown).

[0135] In order to ensure that the air path forming part 233 is large, the size of the circuit substrate 220 needs to be reduced to promote integration. In addition, when the charging device is divided into four equal parts by the center line X1 and the center line X2, the fan 230 is arranged in a manner that the center point is included in the right rear area, and the second opening 206 as the exhaust port is arranged in the right lower area divided into four equal parts. In this way, the air path forming part 233 is ensured to be large, and if its length L5 can be ensured to be approximately half of the depth (front-to-back length) of the charging device shell 2, the distance to the second opening 206 as the exhaust port can be increased without increasing the flow resistance, and the operating sound transmitted to the outside can be greatly suppressed compared with the previous charging device.

[0136] As mentioned above, the present invention has been described based on the embodiments, but the present invention is not limited to the embodiments, and various changes can be made without departing from the main purpose thereof. For example, the configuration of the fan 30 and the air path forming portion 33 of the charging device is not limited to the configuration of the embodiments, and any configuration structure can be used as long as it can be configured to fully ensure the distance from the fan 30 to the exhaust port formed by the air path forming portion 33. The second opening portion and most of the fan can also be arranged in the same area (for example, the right front area) when the charging device is divided into four equal parts by the center line X1 and the center line X2. In this case, the distance of the air path can be ensured by changing the wind direction by using the outer air guide wall 34 and the outer air guide wall 134 as in the first and second embodiments. Alternatively, it can be configured to configure a straight air path like the third embodiment along the long side direction (left-right direction) of the charging device, and make the area containing the fan different from the area forming the exhaust port. In these structures, Fig.10 Compared with the structure of the prior art example shown, the distance from the fan to the exhaust port can be sufficiently ensured. In addition, when the charging device is divided into four equal parts by the center line X1 and the center line X2, the second opening 6 (exhaust port) is formed in the same area, but the second opening 6 can also be formed to span two areas in the same way as the first opening 5.

Claims

1. A charging device, characterized in that: include: A housing on which the battery pack can be loaded and unloaded; a charging circuit unit, housed in the shell and configured to charge the battery pack; a fan, housed in the housing and configured to generate cooling air for cooling the charging circuit unit; A first opening is formed in the wall of the shell and guides external air into the shell; A second opening portion is formed in the wall portion of the shell and exhausts the cooling air; as well as an air path forming portion extending in a substantially horizontal manner from the downstream side of the fan to the second opening portion when the charging device is installed, and forming a cooling air path for the cooling air to pass between the fan and the second opening portion, When the housing is divided into four equal parts by left-right and front-back center lines when viewed from above, more than half of the fan is located in a region different from a region where the first opening is located and in a region different from a region where the second opening is located. The fan is arranged on the downstream side of the charging circuit unit. The air path forming portion includes: a guide portion extending in a lateral direction intersecting with the exhaust direction of the fan and preventing airflow in a direction opposite to the lateral direction; and a duct portion that guides the cooling air guided by the guide portion to the second opening portion without passing through the battery pack.

2. The charging device according to claim 1, characterized in that: The wall portion of the air path forming portion exists on a virtual straight line connecting the outer edge portion of the case forming the second opening and the end portion of the fan on the side close to the second opening.

3. The charging device according to claim 1 or 2, characterized in that: The cooling air passage is provided beside or above the circuit substrate on which the charging circuit unit is mounted.

4. The charging device according to claim 1 or 2, characterized in that: The fan is arranged on the downstream side of the charging circuit unit. When the housing is divided into four equal parts by the left-right and front-back center lines when viewed from above, the second opening is located in one of the four equal parts.

5. The charging device according to claim 1 or 2, characterized in that: The fan is arranged on the downstream side of the charging circuit unit. When the shell is divided into four equal parts by left and right and front and back center lines when viewed from above, more than half of the fan is located in one of the four divided areas, and the second opening is located in an area different from the area where more than half of the fan is located.

6. The charging device according to claim 1 or 2, characterized in that: The cooling air passage includes: a first region provided on the fan side; and a second region provided continuously with the first region on the second opening side, wherein the maximum width of the flow direction cross-sectional area of ​​the second region is greater than the maximum width of the first region.

7. The charging device according to claim 1 or 2, characterized in that: A battery pack connection portion for mounting the battery pack is provided on the upper surface of the shell, and the fan and the cooling air path are located below the battery pack connection portion.

8. The charging device according to claim 1 or 2, characterized in that: The maximum height of the cooling air duct in the upper and lower parts is greater than the maximum width in the left and right parts.

9. The charging device according to claim 1 or 2, characterized in that: The case includes a circuit arrangement region in which the charging circuit unit is arranged, and an air duct arrangement region in which the cooling air duct is arranged separately from the circuit arrangement region.

10. The charging device according to claim 1 or 2, characterized in that: The housing has a battery pack connection portion, and the battery pack can be attached and detached therefrom. The fan is arranged on the downstream side of the charging circuit unit. The second opening is formed in the shell away from the battery pack connection portion and is an exhaust port for exhausting the cooling air to the outside of the shell. The air path forming portion connects the exhaust side of the fan and the exhaust port to form a cooling air path through which the cooling air passes without passing through the battery pack.

11. The charging device according to claim 10, characterized in that: The exhaust port is arranged on the side surface of the shell.

12. The charging device according to claim 10, characterized in that: The air passage forming portion is provided along a side surface of the case.

13. The charging device according to claim 1 or 2, characterized in that: The shell includes: a lower shell for accommodating the charging circuit unit; and an upper shell fixed to the lower shell above the lower shell. The air passage forming portion is formed by the upper case and the lower case.

14. The charging device according to claim 1 or 2, characterized in that: The housing includes: a battery pack connection portion, on which the battery pack can be attached and detached; and a connection portion opening portion, which faces the opening of the battery pack when the battery pack is mounted on the battery pack connection portion. The fan generates cooling air for cooling the battery pack through the connection portion opening, and generates cooling air for cooling the charging circuit portion.

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