JP2008204981A - Capacitor unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To miniaturize a capacitor unit, and to reduce its weight by controlling the voltage across each capacitor, using a single circuit board. <P>SOLUTION: The capacitor unit comprises a plurality of capacitors 5 that have electrodes on both the end faces and are arranged side by side; a first bus bar 11 electrically connecting one electrode of adjacent capacitors 5 in the plurality of capacitors 5; a second bus bar (not shown) electrically connecting the other electrodes of the adjacent capacitors 5 of the plurality of capacitors 5; a circuit board 32 arranged on one electrode side or the other electrode side of the plurality of capacitors 5; a first conductive section 13 connecting the first bus bar 11 to the circuit board 32; and a second conductive section 15 connecting the second bus bar to the circuit board 32. The voltage across each capacitor 5 can be measured using only a single circuit board 32, and the capacitor unit can be miniaturized and reduced weight. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a capacitor unit that stores electric power with a capacitor and is used as an auxiliary power source or the like.

  In recent years, vehicles equipped with a hybrid system and an idling stop system have been developed from the viewpoint of environmental protection, but these systems regenerate the braking energy of the vehicle as electric energy or drive a high output motor. In order to do so, it is necessary to have a configuration in which electrical energy is temporarily stored in the storage element.

  As such a configuration, for example, Patent Document 1 describes a battery unit that stores electrical energy in a battery and backs up an information processing apparatus.

  As shown in FIG. 7, this battery unit was provided with a plurality of batteries 1 having electrodes on both end faces, and a bus bar 2 made of a plate metal that electrically connected the plurality of batteries 1.

  The bus bars 2 are alternately arranged at both ends of the plurality of batteries 1, and the plurality of batteries 1 connected by the bus bar 2 are connected in a plurality of stages and placed in the horizontal direction. Further, an insulating sheet 3 is provided between the stages to prevent a short circuit.

With the above configuration, the battery unit normally stores electric energy in the battery, and supplies power to the information processing apparatus when the power supply source shows an abnormality due to a power failure or the like.
JP 2003-309935 A

  Certainly, the battery unit can back up necessary power to the information processing apparatus or the like in the event of a power failure or the like to prevent the system from going down. However, when this battery unit is used in a vehicle, the following problems occur.

  That is, in a vehicle regenerative system, it is necessary to store suddenly changing braking energy as electrical energy in a power storage element, and in the case of motor drive assistance, it is necessary to supply electrical energy only to accelerate the vehicle. However, the battery 1 used as the storage element of the conventional battery unit is inferior in rapid charge / discharge characteristics.

  On the other hand, instead of the battery 1, a configuration using a capacitor capable of rapid charging / discharging may be used. However, when the voltage at both ends of the capacitor becomes higher than a predetermined value, deterioration of characteristics may be promoted. . Therefore, when using capacitors, it is necessary to provide a voltage balance circuit for measuring and controlling the voltage across each capacitor. When this is applied to the configuration of a conventional battery unit, the bus bars 2 are alternately provided at both end portions 4 of the capacitor. Therefore, it is necessary to provide a circuit board having a voltage balance circuit at both end portions 4 of the capacitor. There was a problem that the unit was increased in size and weight.

  In view of the above, an object of the present invention is to reduce the size and weight of a capacitor unit.

  In order to achieve this object, the present invention electrically connects a plurality of capacitors having electrodes on both end faces and arranged in parallel, and one electrode of adjacent capacitors among the plurality of capacitors. A first bus bar to be connected; a second bus bar to electrically connect the other electrodes of adjacent capacitors among the plurality of capacitors; and one electrode side or the other electrode side of the plurality of capacitors. A circuit board disposed on the first bus bar; a first conductive part that connects the first bus bar and the circuit board; and a second conductive part that connects the second bus bar and the circuit board; did.

  With the above configuration, according to the present invention, the voltage across the capacitor can be measured and controlled only by the circuit board disposed on one end face side, so that the capacitor unit can be reduced in size and weight.

(Embodiment 1)
Hereinafter, the configuration of the capacitor unit according to the first embodiment of the present invention will be described with reference to the drawings.

  In FIG. 1, a plurality of capacitors 5 are cylindrical electric double layer capacitors having a diameter of 3 cm, and thereby store electric power. The cylindrical portion and the end face portion of the capacitor 5 are both made of aluminum. The capacitor 5 is configured such that one end surface is a positive electrode and the other end surface is a negative electrode, and in the first embodiment, the capacitors 5 are connected in series, so that the polarities of the end surfaces of adjacent capacitors 5 are the same. Are arranged different from each other. The semicircular protrusion 7 integrally formed with the upper end surface 6 of the capacitor 5 is configured to have a height higher than that of the end surface peripheral portion 8. The end face peripheral portion 8 is configured to ensure insulation between the positive electrode and the negative electrode. Note that no protrusion is provided on the lower end surface 9 of the capacitor 5. Further, a pressure regulating valve 10 is provided on the upper end surface of the capacitor 5. When the electrolytic solution inside the capacitor 5 is vaporized, the pressure regulating valve 10 releases the vaporized electrolytic solution from the discharge hole 10a provided on the outer surface of the pressure regulating valve 10, and prevents the pressure inside the capacitor 5 from rising. .

  The first bus bar 11 is disposed above the capacitor 5 and electrically connects the protruding portions 7 of the adjacent capacitors 5. A protruding first conductive portion 13 is integrally formed on the upper surface of the first bus bar 11. Since this first conductive portion 13 is connected to a circuit board, which will be described later, by soldering, tin plating is applied. By connecting the first conductive portion 13 to the circuit board, a voltage value at the first bus bar 11 is obtained. Can be detected.

  On the other hand, the second bus bar 14 is disposed below the capacitor 5 and electrically connects the lower end faces 9 of the adjacent capacitors 5. The second bus bar 14 is integrally formed with a plate-like second conductive portion 15. Similar to the first conductive portion 13, the second conductive portion 15 has a terminal portion 15a corresponding to the tip thereof tin-plated, and the second bus bar 14 is connected by connecting the terminal portion 15a to a circuit board described later. The voltage value at can be detected. The second conductive portion 15 is provided with a bent portion 15b. The bent portion 15b absorbs stress due to vibration and heat, and the second conductive portion 15 itself, the terminal portion 15a, and a circuit board described later are provided. This can reduce the possibility of breakage of the soldering portion.

  The L-shaped bus bar 16 is connected to the protruding portion 7 of the capacitor 5 located at the end, and an L-shaped bus bar screw hole 16a is provided for electrical connection with external wiring. Connection with external wiring will be described later.

  The first bus bar 11, the second bus bar 14, and the L-shaped bus bar 16 are made of the same aluminum as the cylindrical portion and the end surface portion of the capacitor 5 in order to improve weldability with the electrode of the capacitor 5. Yes, it can be obtained by press molding an aluminum plate. In the first embodiment, the first bus bar 11, the second bus bar 14, and the L-shaped bus bar 16 are made of aluminum, but a metal other than aluminum may be used as long as it is the same as the electrode of the capacitor 5.

  The upper case 17 is made of resin, and is fixed by inserting the upper part of the capacitor 5. The upper case 17 is provided with a first bus bar opening 18 and an L-shaped bus bar opening 19 for connecting the first bus bar 11 and the L-shaped bus bar 16 and the protruding portion 7. The upper case 17 is provided with a second conductive portion hole 20, and the second conductive portion 15 is fixed by being inserted into the second conductive portion hole 20. In FIG. 1, an insert nut 21 is embedded in the left end portion of the upper case 17, and the L-shaped bus bar 16 and an external bus bar (described later) are electrically and mechanically connected by the insert nut 21. Further, an upper fixing screw hole 22 is provided near the L-shaped bus bar opening 19. The fixing rod 23 and the upper case 17 are fixed by disposing the fixing rod 23 at the position of the upper fixing screw hole 22 and tightening the upper fixing screw 24 from above. At this time, the upper fixing screw 24 is a countersunk screw so that the L-shaped bus bar 16 and the upper fixing screw 24 do not contact each other. Although not shown, an upper fixing screw hole for attaching the fixing rod 23 is also provided at the right end of the upper case 17.

  Similarly to the upper case 17, the lower case 25 is made of resin. A circular holding hole 26 is provided on the upper surface of the lower case 25, and the lower part of the capacitor 5 is inserted and fixed in the holding hole 26. Further, a cutout portion 27 is provided on the side surface of the lower case 25, and the second conductive portion 15 formed integrally with the second bus bar 14 is inserted into the cutout portion 27. As in the case of the upper case 17, a lower fixing screw hole 28 is provided at the left end of the lower case 25 in FIG. 1, and the fixing rod 23 arranged at the position of the lower fixing screw hole 28 is made of a countersunk screw. The fixing rod 23 and the lower case 25 are fixed by tightening the lower fixing screw 29. Although not shown, a lower fixing screw hole for attaching the fixing rod 23 is also provided at the right end of the lower case 25.

  FIG. 2 shows a state where the above components are assembled. The upper case 17 and the lower case 25 are connected by a fixing rod 23, and the capacitor 5 is firmly fixed by being sandwiched between the upper case 17 and the lower case 25.

  The first bus bar 11 and the L-shaped bus bar 16 cover the projecting portion 7 provided on the upper end surface of the capacitor 5. Here, the connection between the first bus bar 11 and the L-shaped bus bar 16 and the projecting portion 7 is performed by laser welding the portion indicated by x in FIG. 2, thereby ensuring reliable electrical connection with the capacitor 5. And mechanical connection is obtained. In addition, although the example which welded many points | pieces in the spot form was shown in FIG. 2, this may be weld-connected linearly, shifting a welding position sequentially. In this case, the connection reliability is improved as compared with the spot shape. Although not shown, the second bus bar 14 is also welded to the lower end surface of the capacitor 5 in the same manner.

  In order to wire the capacitor unit formed in this way to the outside, the external bus bar 30 and the external bus bar screw hole 30a are fastened and fixed to the insert nut 21 with the screw 31. At this time, since it is fixed via the L-shaped bus bar 16, the external bus bar 30 and the L-shaped bus bar 16 are electrically connected. The external bus bar 30 is formed with an external bus bar bent portion 30b. Thereby, the stress by vibration and heat is absorbed by the external bus bar bent portion 30b, and the possibility that the external bus bar 30 is damaged can be reduced.

  Here, since the second conductive portion 15 is inserted into the second conductive portion hole 20, the terminal portion 15 a protrudes from the upper surface of the upper case 17. Further, the bent portion 15 b provided in the second conductive portion 15 is located between the upper case 17 and the lower case 25. In this state, the terminal portion 15a and the first conductive portion 13 are inserted into the first conductive portion hole 33 and the terminal hole 34 provided in the circuit board 32 and soldered, whereby the first bus bar 11 and the second conductive portion 13 are connected. Bus bar 14 and L-shaped bus bar 16 are electrically connected to circuit board 32.

  The circuit board 32 has a voltage balance circuit (not shown) for measuring and controlling the voltage of each capacitor 5.

  By assembling so far, the capacitor unit is completed as shown in FIG.

  Next, FIG. 4 shows a cross-sectional view of a rectangular portion indicated by a dotted line in FIG.

  As described above, since the protrusion 7 is provided with a height higher than that of the end surface peripheral portion 8, the first bus bar 11 is in contact with the end surface peripheral portion 8 and short-circuited as is apparent from FIG. There is no.

  Further, since the pressure regulating valve 10 covers and covers a part of the cover portion 17a of the upper case 17, the circuit board 32 and the first bus bar 11 are separated from each other. Thereby, even if the electrolyte in the capacitor 5 vaporized from the pressure regulating valve 10 is discharged, it does not adhere to the first bus bar 11 or the circuit board 32, and the possibility of corrosion is reduced and high reliability is obtained. It is done. Further, the pressure regulating valve 10 is lower in height than the end surface peripheral portion 8, and there is a gap between the pressure regulating valve 10 and the upper case 17 disposed on the pressure regulating valve 10. Therefore, since the discharge hole 10a is not blocked, the electrolytic solution vaporized from the discharge hole 10a can be normally discharged.

  In addition, since the thickness of the bottom surface of the lower case 25 is provided to be greater than the thickness of the second bus bar 14, the second bus bar 14 does not come in contact with anything other than the capacitor 5 and the lower case 25. Accordingly, leakage from the second bus bar 14 can be prevented, and high reliability can be obtained.

  Next, the operation of the capacitor unit in the first embodiment of the present invention will be described below.

  As described above, if the voltage at both ends of the capacitor 5 becomes too high, the deterioration of the characteristics may proceed. In order to prevent the deterioration of the characteristics, the voltages of the first bus bar 11 and the second bus bar 14 are sequentially measured. The voltage across the capacitor 5 must be controlled. By performing this with one circuit board 32, the capacitor unit is reduced in size and weight in the first embodiment.

  Next, the effect in Embodiment 1 of this invention is demonstrated below.

  First, in Embodiment 1, the voltage across each capacitor 5 can be measured with a single circuit board 32, and the capacitor unit can be reduced in size and weight.

  This electrically connects the first bus bar 11 and the voltage balance circuit of the circuit board 32 via the first conductive portion 13, and similarly the second bus bar 14 via the second conductive portion 15. And the voltage balance circuit of the circuit board 32 are electrically connected, and the voltage across each capacitor 5 is measured. With this configuration, the voltage across each capacitor 5 can be measured only with the circuit board 32 arranged on the upper side of the upper case 17. As a result, the capacitor unit can be reduced in size and weight.

  Further, the first conductive portion 13 and the second conductive portion 15 are formed integrally with the first bus bar 11 and the second bus bar 14, respectively. Thereby, the 1st electroconductive part 13 and the 2nd electroconductive part 15 are connected with the 1st bus bar 11 and the 2nd bus bar 14, respectively, respectively, and it can reduce the possibility of the damage in a connection part. In particular, when the capacitor unit is mounted on a vehicle, this configuration is useful because vibration of the vehicle is expected to be transmitted to the capacitor unit.

  In addition, as shown to Fig.5 (a), (b), the 2nd bus-bar 14 and the 2nd electroconductive part 15 may be made into a different body, and may be weld-connected. Also in this configuration, the second bus bar 14 and the second conductive portion 15 are securely connected. Furthermore, it is preferable that the second bus bar 14 and the second conductive portion 15 are made of the same metal in order to improve the weldability, and the area of the welded portion 35 shown in FIG. By enlarging, the second bus bar 14 and the second conductive portion 15 can be connected more reliably.

  Moreover, in this Embodiment 1, it is set as the structure which arrange | positions so that the capacitor 5 may be arrange | positioned in the vertical installation state mutually parallel, and the pressure regulation valve 10 may become an upper side. As a result, the possibility of electrolyte leakage from the pressure regulating valve 10 can be reduced, and high reliability can be obtained.

  In addition, it is good also as a structure by which the capacitor 5 is arrange | positioned in the horizontal installation state mutually parallel, and the pressure regulation valve 10 is arrange | positioned above the center of one end surface. Thus, even when the capacitor units are arranged in the horizontal direction, the voltage of each capacitor 5 can be measured with the circuit board 32 provided only on one end face side of the capacitor 5 by using the configuration of the present invention. The capacitor unit can be reduced in size and weight. Furthermore, since the pressure regulating valve 10 is disposed above the center of the end face of the capacitor 5, the possibility that the electrolyte leaks from the pressure regulating valve 10 can be reduced. In addition, since the capacitor unit mounted on the vehicle is often mounted under the floor and is exposed to severe vibration conditions and requires a low profile, the capacitor 5 is placed in a parallel horizontal state as described above. If the overall height is lowered, it is suitable as a capacitor unit for vehicles.

  Although the cylindrical capacitor 5 is employed in the first embodiment of the present invention, the present invention is not limited thereto, and a prismatic or other shape capacitor may be employed.

(Embodiment 2)
The difference between the second embodiment and the first embodiment is that the second conductive portion 15 and the circuit board 32 are connected via a flexible cable 36 as shown in FIG.

  A substrate connector 37 is provided at one end of the flexible cable 36, and a bus bar connector 38 is provided at the other end. The board connector 37 is inserted into a socket 39 mounted on the circuit board 32, and the bus bar connector 38 is connected to the terminal part 15 a at the end of the second conductive part 15. As a result, the second bus bar 14 and the circuit board 32 are electrically connected.

  Also with this configuration, the voltage across the capacitor 5 can be measured only with the circuit board 32 disposed on the upper side of the upper case 17, and the capacitor unit can be reduced in size and weight.

  Note that the same effect can be obtained by using electric wires in which the board connector 37 and the bus bar connector 38 are attached to both ends instead of the flexible cable 36.

  Since the capacitor unit according to the present invention can measure the voltage across each capacitor on a single circuit board and can reduce the size and weight of the capacitor unit, it is particularly suitable as a capacitor unit as an auxiliary power source for vehicles. Useful.

1 is an exploded perspective view of a capacitor unit according to Embodiment 1 of the present invention. 1 is a partially assembled perspective view of a capacitor unit according to Embodiment 1 of the present invention. The completed perspective view of the capacitor unit in Embodiment 1 of this invention Partial sectional view of the capacitor unit according to the first embodiment of the present invention. The 2nd bus bar of other composition of the capacitor unit in Embodiment 1 of the present invention is shown, (a) The perspective view before welding connection of the 2nd electric conduction part to the 2nd bus bar, (b) 2nd Perspective view after welding connection of second conductive part to bus bar The perspective view before the flexible cable connection of the capacitor unit in Embodiment 2 of this invention A perspective view of a conventional battery unit

Explanation of symbols

DESCRIPTION OF SYMBOLS 5 Capacitor 6 Upper end surface 7 Protrusion part 8 End surface surrounding part 9 Lower end surface 10 Pressure regulating valve 10a Release hole 11 1st bus bar 13 1st electroconductive part 14 2nd bus bar 15 2nd electroconductive part 15a Terminal part 15b Bending part 16 L-shaped bus bar 16a L-shaped bus bar screw hole 17 Upper case 18 First bus bar opening 19 L-shaped bus bar opening 20 Second conductive part hole 21 Insert nut 22 Upper fixing screw hole 23 Fixing rod 24 Upper fixing screw 25 Lower case 26 Holding hole 27 Notch 28 Lower fixing screw hole 29 Lower fixing screw 30 External bus bar 30a External bus bar screw hole 30b External bus bar bent part 31 Screw 32 Circuit board 33 First conductive part hole 34 Terminal hole 35 Welded part 36 Flexible Cable 37 Board connector 38 Busbar connector 39 socket

Claims (6)

A plurality of capacitors having electrodes on both end faces and arranged in parallel;
A first bus bar that electrically connects one electrode of adjacent capacitors among the plurality of capacitors;
A second bus bar for electrically connecting the other electrodes adjacent to each other among the plurality of capacitors;
A circuit board disposed on one electrode side or the other electrode side of the plurality of capacitors;
A first conductive portion connecting the first bus bar and the circuit board;
A capacitor unit comprising the second bus bar and a second conductive portion connecting the circuit board. The capacitor unit according to claim 1, wherein the first conductive portion and the second conductive portion are integrally formed with the first bus bar and the second bus bar, respectively. The capacitor unit according to claim 1, wherein the conductive portion is a flexible cable or an electric wire. An upper case and a lower case for holding the capacitors in parallel with each other by inserting the one end surface and the other end surface of the capacitor are provided, and a part of the upper case is provided on the upper case side of the capacitor The capacitor unit according to claim 1, wherein a cover portion that separates the pressure regulating valve from the bus bar and the circuit board is formed. 5. The capacitor unit according to claim 4, wherein the plurality of capacitors are arranged such that the pressure regulating valve is on an upper side in a vertically placed state parallel to each other. 2. The capacitor unit according to claim 1, wherein the plurality of capacitors are arranged in a horizontally placed state parallel to each other, and the pressure regulating valve is arranged to be above the center of the one end face.

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