JP2008204989A - Capacitor unit and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high-reliability low-profile capacitor unit and its manufacturing method. <P>SOLUTION: By having a configuration and the manufacturing method of the capacitor unit set, such that a capacitor 11 is held horizontally by a holding section 19 so that a pressure regulation valve 15 provided at a positive electrode 12 in the cylindrical large-capacity capacitor 11, having electrodes on both end faces is at the upper side and a positioning projection 14 provided at the positive electrode 12 in the capacitor 11, is inserted into a fitting section 21 provided in an upper case 20; then the electrodes of the adjacent capacitors 11 are welded and jointed by a bus bar, and finally a bus bar terminal integrated with the bus bar and a circuit board arranged on the side of the case are connected electrically. Thus, by the horizontal arrangement of the capacitor 11 at the holding section 19, arrangement of the circuit board to the side of the case, and the stress-free welding connection of the bus bar, a high-reliability low-profile capacitor unit can be realized. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a capacitor unit mainly used for a power storage device of a hybrid vehicle and a manufacturing method thereof.

  In recent years, in particular, hybrid vehicles have been rapidly developed from the viewpoint of protecting the global environment, and various proposals have been made for power storage devices that store electric power for driving motors.

  Secondary batteries are mainly used in such power storage devices, but secondary batteries have insufficient rapid charge / discharge characteristics. For example, during rapid acceleration, sufficient power can be supplied to the motor. Have difficulty.

  In view of this, a system has been devised that improves acceleration performance by using a capacitor with excellent rapid charge / discharge characteristics and supplying power from both the capacitor and the secondary battery to the motor. In addition, a system for storing electricity using only a capacitor instead of a secondary battery has been proposed.

  Although the acceleration performance can be improved by using such a system, a large-capacity capacitor is required in order to store electric power enough to accelerate the vehicle or perform hybrid running, and a general capacitor voltage (2. Since the voltage is low at about 2 V), it is necessary to increase the voltage by connecting a plurality of capacitors. Therefore, the required individual capacitors are increased in size and must be configured as a capacitor unit using a plurality of them. In this case, a capacitor unit including a plurality of large-capacity capacitors (for example, a diameter of about 5 cm and a capacity of about several thousand F) has an extremely large outer size. It becomes the composition arranged in the space.

In order to realize this, it is necessary to reduce the height of the capacitor unit, so a configuration in which a plurality of capacitors are arranged in the horizontal direction is conceivable. An example of such an arrangement is described in Patent Document 1. This is an example of a backup power supply at the time of a power failure. As shown in FIG. 11, the battery 1 is arranged so that the positive electrode and the negative electrode are adjacent to each other, and the two electrodes are sequentially connected by the conductive material 2 (bus bar). Thus, a plurality of batteries (seven in FIG. 11) are connected in series. This is connected to a plurality of stages (four stages in FIG. 11), and an insulating sheet 3 is provided between the stages. In this way, the battery pack 4 is formed. With the above configuration, the backup power supply with high voltage output is made thin (low profile).
JP 2003-309935 A

  Such a backup power source can certainly be reduced in height, for example, for a backup power source disposed in a gap such as a lower portion of an information processing device rack mainly used indoors, and the information processing device and the backup power source are integrated. Can contribute to the overall size reduction.

  However, considering the case where the backup power supply having such a configuration is mounted on a vehicle, it is assumed that reliability with respect to vehicle vibration is particularly insufficient. That is, since each battery 1 is only connected by the conductive material 2, and only the insulating sheet 3 is provided between the stages, the battery 1 is restrained and fixed to vibration. It is not. Accordingly, there is a possibility that stress is concentrated on the conductive material 2 due to movement of the heavy battery 1 due to vehicle vibration, and the conductive material 2 and the electrode of the battery 1 may be damaged. Even if the battery 1 is changed to a large capacitor, there is a sufficient possibility that the battery 1 is similarly damaged.

  Therefore, the configuration of the conventional low-profile backup power source has a problem that the reliability for the vehicle is insufficient.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a highly reliable low-profile large-capacity capacitor unit and a method for manufacturing the same.

  In order to solve the above-mentioned conventional problems, the capacitor unit of the present invention, and the manufacturing method thereof, first, the pressure regulating valve provided on one electrode of the cylindrical large-capacity capacitor having electrodes on both end faces is on the upper side. And after holding the capacitor in the holding portion of the case in the horizontal direction so that the positioning convex portion provided on one of the electrodes of the capacitor is inserted into the fitting portion provided in the case, the adjacent capacitors The electrodes are welded and joined with a bus bar, and finally, a bus bar terminal integrally formed with the bus bar and a circuit board disposed on the side surface of the case are electrically connected and a manufacturing method is provided.

  As a result, since the capacitor and the bus bar are connected after the fixing of the large capacity capacitor arranged in the horizontal direction to the holding portion is completed, no stress is applied to the electrode of the capacitor when the bus bar is connected. Further, since the capacitor itself is fixed to the holding portion and is firmly connected by welding, the capacitor does not move even when vehicle vibration is applied, and stress on the bus bar can be avoided. Furthermore, since the circuit board is disposed on the side surface of the case, the thickness of the case can be made substantially equal to the height of the capacitor. As a result, the object can be achieved.

  According to the capacitor unit and the manufacturing method thereof of the present invention, it is possible to reduce the height by arranging the large-capacity capacitor in the horizontal direction and the case side of the circuit board, and fixing the capacitor to the holding portion; By stress-free welding connection with the bus bar, stress concentration due to vibration is reduced and high reliability can be obtained at the same time.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 is a partially exploded perspective view of a capacitor unit according to Embodiment 1 of the present invention. FIG. 2 is a perspective view showing bus bar connection in the method for manufacturing the capacitor unit according to Embodiment 1 of the present invention. FIG. 3 is a perspective view showing a circuit board and flexible cable attachment in the method for manufacturing the capacitor unit according to Embodiment 1 of the present invention. FIG. 4 is a completed perspective view of the capacitor unit according to the first embodiment of the present invention.

  The capacitor unit according to the first embodiment will be described by taking a capacitor combined system for a secondary battery hybrid vehicle as an example.

  In FIG. 1, a plurality of capacitors 11 are cylindrical large-capacity electric double layer capacitors having a diameter of about 5 cm, and electrodes are provided on both end faces thereof. The electrode is configured such that one end face is the positive electrode 12 and the other end face is the negative electrode 13. In the first embodiment, the positive electrode 12 is provided with the positioning convex portion 14, the pressure regulating valve 15, and the protruding portion 16 in which a part of the positive electrode 12 protrudes from the cylindrical shape at two places. Among these, the positioning convex portion 14 and the protruding portion 16 are formed integrally with the positive electrode 12. Further, the positive electrode 12 has a structure that is caulked through an insulating portion (not shown) for internal sealing of the capacitor 11. Accordingly, the positive electrode 12 is arranged in one step deeper than the cylindrical end face (the depth is d shown in FIG. 1). On the other hand, the protrusion 16 has a thickness larger than d for welding with a bus bar described later. The positive electrode 12 and the negative electrode 13 are formed with four electrode welds 17 for electrical connection with electrodes (not shown) inside the capacitor 11.

  Since the capacitor 11 is cylindrical, the positioning convex portion 14 is for preventing an electrode welding position with a bus bar to be described later from shifting, and a fitting portion (described later) provided in a case (described later) that holds the capacitor 11. In this configuration, the positioning of the capacitor 11 is determined. Therefore, the height is larger than d, and the position is formed so as to be on the upper side when the capacitor 11 is arranged in the horizontal direction.

  The pressure regulating valve 15 is provided to prevent the internal pressure of the capacitor 11 from increasing when the electrolyte filled in the capacitor 11 is vaporized due to a change in external temperature or the like. The outer surface of the pressure regulating valve 15 is provided with two holes 15a for discharging the vaporized electrolyte. Therefore, the pressure regulating valve 15 is also formed to be on the upper side when the capacitor 11 is arranged in the horizontal direction. Thereby, the possibility that the pressure regulating valve 15 is clogged with the electrolytic solution and the vaporized electrolytic solution is not released can be reduced, and high reliability can be obtained. In the first embodiment, the pressure regulating valve 15 is arranged directly below the positioning convex portion 14. Further, before the pressure regulating valve 15 is attached, the pressure regulating valve 15 is used as an inlet for the electrolyte into the capacitor 11 and the pressure regulating valve 15 is attached after the injection. Therefore, the pressure regulating valve 15 cannot be formed integrally with the positive electrode 12, and is structured to be attached to the positive electrode 12 by caulking.

  In the first embodiment, both the positioning convex portion 14 and the pressure regulating valve 15 are provided on the positive electrode 12, but these may be provided on any one of the electrodes of the capacitor 11. Further, these need not be provided on the same electrode.

  Such a plurality of capacitors 11 (six in this embodiment) are arranged in the resin lower case 18 so that the positive electrodes 12 and the negative electrodes 13 of the adjacent capacitors 11 are alternately arranged in the horizontal direction. The holding part 19 formed integrally and the holding part 19 of the upper case 20 having the same configuration as the lower case 18 are firmly fixed by being sandwiched. At this time, since the upper case 20 has a shape that exposes the pressure regulating valve 15 provided in each capacitor 11, it does not hinder the release of the vaporized electrolyte. Further, by inserting the positioning protrusions 14 provided on each capacitor 11 into the fitting portion 21 formed integrally with the upper case 20, all the electrode directions of each capacitor 11 are aligned.

  Elastic portions 23 are integrally formed with the holding portions 19 of the lower case 18 and the upper case 20, respectively. As shown in FIG. 1, the elastic portion 23 has a U-shaped cutout structure in the holding portion 19 of the upper case 20, and the U-shaped tip is bent toward the holding portion 19 side (lower side in FIG. 1). It is formed in the state. The elastic portion 23 has a size that can sufficiently fix the large capacitor 11 against vehicle vibration, and is provided at two locations for each capacitor 11. Further, although not shown in FIG. 1, a similar elastic portion 23 is also formed in the lower case 18. In this case, the U-shaped tip is formed in a state of bending upward. Therefore, when the capacitor 11 is brought into contact with and sandwiched between the lower case 18 and the upper case 20, the upper and lower elastic portions 23 press the capacitor 11 and can be firmly fixed. The elastic portion 23 may be provided only on either the lower case 18 or the upper case 20.

  Here, lower case screw holes 18a are integrally formed in the lower case 18, and upper case screw holes 20a are integrally formed in the upper case 20, respectively. Therefore, by covering the lower case 18 with the upper case 20, the positions of the lower case screw hole 18a and the upper case screw hole 20a coincide. The upper case 20 and the lower case 18 are fixed by tightening the screws 24 in this state. In addition, although the lower case screw hole 18a and the upper case screw hole 20a are provided in four places in this Embodiment 1, more may be sufficient. In addition to the structure in which the screw 24 is tightened and fixed, the upper case 20 and the lower case 18 are each provided with an elastic portion having a locking portion and a claw portion, and fixed by fitting the claw portion into the locking portion. It is good also as a method to do.

  Further, an insert nut 27 for connecting a power cable (described later) is embedded in an end portion of a bus bar described later in the upper case 20. Further, two bosses 28 for fixing a circuit board, which will be described later, are integrally formed on the side surfaces of the lower case 18 and the upper case 20, respectively.

  Next, a method for assembling the components shown in FIG. 1 will be described.

  First, the capacitor 11 is arranged on the holding portion 19 of the lower case 18. As a result, the capacitors 11 are arranged in the horizontal direction, so that the height can be reduced. At this time, as shown in FIG. 1, the positioning projections 14 are arranged so that the positive electrodes 12 and the negative electrodes 13 are alternately arranged so that the positioning convex portions 14 are on the upper side.

  Next, the upper case 20 is put on the lower case 18. At this time, each capacitor 11 is covered while turning so that all the positioning convex portions 14 are inserted into the fitting portions 21. Thereby, when the lower case 18 and the upper case 20 are fixed with the screws 24, the directions of the electrodes of the capacitors 11 are aligned.

  In addition, in FIG. 1, the positioning convex part 14 may be provided in the lower part of an electrode, and the fitting part 21 may be provided in the lower case 18 in the position corresponding to it. In this case, since the directions of the electrodes are aligned when the capacitor 11 is arranged on the holding portion 19 of the lower case 18, it becomes easier to manufacture.

  Here, the inner diameter of the holding portion 19 is formed to be slightly larger than the outer diameter of the capacitor 11. However, since the elastic portion 23 is bent toward the capacitor 11, the upper case 20 is attached to the lower case 18. The capacitor 11 comes into contact with the elastic portion 23 by being covered, and is firmly fixed by the reaction force of the elastic portion 23 by tightening the screw 24. By adopting such a configuration, the tolerance of the capacitor 11 and the holding portion 19 can be absorbed, so that the capacitor 11 can be reliably fixed.

  The assembled state is shown in FIG. Each capacitor 11 is firmly sandwiched between upper and lower elastic portions 23. Further, a window into which the bus bar 30 is fitted is opened on the electrode side of the capacitor 11 (left and right side in FIG. 1). By inserting the bus bar 30 into the opening 30a, the capacitor 11 is electrically and mechanically connected.

  The bus bar 30 is made of copper having a surface subjected to rust prevention treatment such as plating, and the positioning convex portion 14 and the pressure regulating valve 15 are exposed, and the others are press-molded into a shape covering the opening 30a. Here, bent portions 32 are provided at two locations in a portion excluding a portion that is welded to the positive electrode 12 and the negative electrode 13 and a bus bar terminal 31 that is electrically connected to a circuit board described later. Thereby, since the external stress such as during welding or vehicle vibration applied to the bus bar 30 at the bent portion 32 can be absorbed, the possibility of breakage of the bus bar 30 can be reduced and the reliability is improved. The bus bar terminal 31 and the bent portion 32 are formed integrally with the bus bar 30.

  Next, a method for attaching the bus bar 30 will be described.

  First, the bus bar 30 is fitted into the opening 30a as shown by the arrow in FIG. Next, the portion indicated by x on the bus bar 30 is laser-welded. Thereby, since the resistance of the connection part of an electrode and the bus-bar 30 can be lowered | hung, even if a heavy current flows, the heat_generation | fever in a connection part can be suppressed and the thermal deterioration of the capacitor 11 is reduced. Therefore, high reliability can be obtained.

  The welded portions are portions other than the two protruding portions 16 provided on the positive electrode 12 and the electrode welded portion 17 of the negative electrode 11. As a result, the electrodes of the adjacent capacitors 11 are electrically and mechanically connected. At this time, since the capacitor 11 has already been positioned by the lower case 18 and the upper case 20 and is firmly fixed, it is possible to perform laser welding accurately and without applying stress to the electrodes of the capacitor 11, and reliability. Improves. At the same time, since the bus bar terminal 31 is inserted and fixed in the bus bar terminal groove 33 formed integrally with the upper case 20, the position of the bus bar terminal 31 is also determined. Laser welding is shown as spot welding at 6 points per electrode in FIG. 1. However, when the reliability of the welded part is further required due to factors such as severe vibration conditions at the vehicle installation location. May be continuously welded linearly.

  All the capacitors 11 are electrically and mechanically connected by sequentially performing the above process on each opening 30a. In the first embodiment, all the capacitors 11 are connected in series, but this can be done in parallel by changing the direction of the capacitors 11 or connecting the electrodes of the plurality of capacitors 11 with one bus bar 30. You may connect in series and parallel.

  What was assembled so far is shown in FIG. A bus bar 30 is fixed to each opening 30a. 3, the bus bar 30 on the left front side is the end of the six capacitors 11 in series. Therefore, in order to connect the power cable 34 to the outside, the bus bar 30 is bent at right angles along the lower case 18 and the upper case 20. It has a different shape. The power cable 34 is electrically connected together with the bus bar 30 by being fastened to the insert nut 27 by the screw 24.

  Circuit boards 36 are arranged on the side surfaces of the lower case 18 and the upper case 20. In the first embodiment, a circuit for controlling the voltage balance of each capacitor 11 is formed on the circuit board 36, but drawing of the circuit components is omitted. Since the voltage balance control circuit of the circuit board 36 according to the first embodiment can be entirely composed of surface-mounted components, the circuit board 36 has a minimum necessary shape smaller than the side areas of the lower case 18 and the upper case 20. It was. Since the screw hole 38 is provided at a position corresponding to the boss 28 of the circuit board 36, the circuit board 36 is fixed to the lower case 18 and the upper case 20 by tightening the screw 24 with the screw hole 38 aligned with the boss 28. It is arranged on the side. The circuit board 36 is arranged on the side surfaces of the lower case 18 and the upper case 20 in this way because the diameter of the capacitor 11 used in the first embodiment is as large as about 5 cm, and if the thickness of the capacitor unit is further increased, the vehicle This is because it cannot be installed in a dead space such as under the floor.

  Each bus bar terminal 31 and the circuit board 36 are connected by a flexible cable 39. Thereby, since the flexible cable 39 has flexibility, even if it solders with the bus-bar terminal 31, there is almost no influence of the stress to the bus-bar 30, and reliability improves.

  Next, a method for attaching the circuit board 36 and the flexible cable 39 will be described.

  First, the circuit board 36 is fastened to the boss 28 with the screw 24. As a result, the circuit board 36 is fixed to the side surfaces of the lower case 18 and the upper case 20.

  Next, the bus bar terminal 31 is inserted into the terminal hole 37 provided in the flexible cable 39 and soldered. Thereby, the bus bar 30 and the flexible cable 39 are electrically connected.

  Finally, the flexible cable terminal 39a provided on the flexible cable 39 is connected to the circuit board 36 by soldering. By such a process, the bus bar 30 and the circuit board 36 are electrically connected. The flexible cable terminal 39a and the circuit board 36 may be connected via a connector in addition to direct soldering. The connection between the bus bar 30 and the circuit board 36 is not limited to the flexible cable 39, and a general cable or a flat cable obtained by joining a plurality of cables may be used.

  The power cable 34 may be attached at any time before and after the circuit board 36 and the flexible cable 39 are attached.

  The capacitor unit thus assembled is shown in FIG. Since the circuit board 36 is disposed at a position that does not face the pressure regulating valve 15 of each capacitor 11, even if the vaporized electrolyte is discharged from the pressure regulating valve 15, the possibility of directly contacting the circuit board 36 is reduced. . Therefore, the possibility of corrosion of the circuit board 36 is reduced and the reliability is increased.

  The manufacturing method of the capacitor unit having the above configuration is summarized as follows.

  1) The capacitor 11 is held by the holding portion 19 so that the pressure regulating valve 15 is on the upper side and the positioning convex portion 14 is inserted into the fitting portion 21, and is sandwiched between the lower case 18 and the upper case 20.

  2) The bus bar 30 is welded and joined between the electrodes of the adjacent capacitors 11 located in the opening 30a.

  3) The circuit board 36 is fixed to the side surfaces of the lower case 18 and the upper case 20.

  4) The bus bar terminal 31 formed integrally with the bus bar 30 and the circuit board 36 are electrically connected.

  In this way, after fixing the capacitor 11, the bus bar 30 is welded and joined, or the bus bar terminal 31 and the circuit board 36 are electrically connected via the flexible cable 39 so that no stress is applied to the bus bar 30. The manufacturing method can reduce the influence of stress on the eleventh electrode and obtain high reliability.

  With the above configuration and manufacturing method, the capacitor 11 is arranged in the horizontal direction and the circuit board 36 is disposed on the side surfaces of the lower case 18 and the upper case 20, and the bus bar 30 can be manufactured without applying stress. Since the capacitor 11 is firmly held between the lower case 18 and the upper case 20 and the bus bar 30 is firmly fixed to the electrode of the capacitor 11 by welding, a high-reliability low-profile and large-capacity capacitor unit is obtained.

  In the first embodiment, six capacitors 11 are used. However, it is sufficient to mount a necessary quantity according to the power specifications required for the capacitor unit. Further, for example, when a high voltage is required as in a power storage device for driving a hybrid vehicle, a configuration may be adopted in which a plurality of capacitor units are connected.

(Embodiment 2)
FIG. 5 is a partially exploded perspective view of the capacitor unit according to Embodiment 2 of the present invention. FIG. 6 is a perspective view showing bus bar connection in the method for manufacturing a capacitor unit according to the second embodiment of the present invention. FIG. 7 is a perspective view showing a connection method by caulking of the bus bar terminal of the capacitor unit and the cable according to the second embodiment of the present invention. FIG. 8 is a perspective view showing a circuit board and flat cable attachment in the method for manufacturing a capacitor unit according to the second embodiment of the present invention. FIG. 9 is a completed perspective view of the capacitor unit according to the second embodiment of the present invention.

  In the second embodiment as well, as in the first embodiment, a description will be given of an example for a capacitor combined system of a secondary battery hybrid vehicle. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  That is, the differences from the first embodiment are as follows.

  1) The holding portion 19 is provided only on both electrode sides of the capacitor 11 so that the central portion of the capacitor 11 is exposed.

  2) Thus, the case was divided into a right case 40 and a left case 41.

  3) Since the center portion of the capacitor 11 is exposed, the right case 40 and the left case 41 cannot be directly mechanically connected. Therefore, the screws from the right case 40 and the left case 41 are screwed via the female screw rods 42 arranged on the exposed portion. 24 was connected.

  4) Since the screw 24 is fastened to the female threaded rod 42, the screw hole 38 provided in the right case 40 and the left case 41, and the position that does not interfere with the holding portion 19 (specifically, the left case 41 in FIG. The insert nut 27 was moved to the lower part.

  5) Since the holding portion 19 is provided only on both electrode sides of the capacitor 11, the shape of the elastic portion 23 provided in the holding portion 19 was changed.

  6) Accordingly, a rib 43 for positioning the capacitor 11 is provided in the holding portion 19.

  First, the structure of the capacitor unit according to the second embodiment will be described focusing on the above differences.

  As shown in FIG. 5, the case for fixing the capacitor 11 is divided into a right case 40 and a left case 41. The capacitor 11 is fixed by being inserted into a cylindrical holding portion 19 provided in the right case 40 and the left case 41.

  Here, details of the holding portion 19 will be described. As in the first embodiment, the holding portion 19 is provided with an elastic portion 23 for firmly fixing the capacitor 11, but the shape of the holding portion 19 includes four cutout portions 44 up to the middle of the holding portion 19 (in FIG. 5). Each holding portion 19 has a structure provided at two upper positions and two lower positions). Accordingly, the elastic portion 23 is located between the two cutout portions 44 in the upper and lower portions. In addition, the notch part 44 is not specifically limited to four places.

  The inner diameter of the holding portion 19 is formed to be slightly larger than the outer diameter of the capacitor 11, but the tip portion of the elastic portion 23 is configured to be thicker. The tip portion and the two cutout portions 44 provide elasticity. Further, ribs 43 are provided on the left and right wall surfaces of the holding portion 19 in FIG. Therefore, when the capacitor 11 is inserted into the holding portion 19 from the direction of the arrow in FIG. 5, the capacitor 11 is guided parallel to the holding portion 19 while abutting the rib 43 while expanding the elastic portion 23. Therefore, the capacitor 11 contacts the elastic portion 23 while being positioned by the rib 43, and is firmly fixed by the elasticity. By adopting such a configuration, the tolerance of the capacitor 11 and the holding portion 19 can be absorbed, so that the capacitor 11 can be reliably fixed. Here, in order to align the position of the capacitor 11 when the capacitor 11 is inserted into the holding portion 19, the direction of the capacitor 11 is adjusted so that the positioning convex portion 14 is inserted into the fitting portion 21 as in the first embodiment. Insert into the holding part 19 while rotating.

  With such a configuration, the central portion of the capacitor 11 is exposed. Therefore, for example, when the capacitor unit is arranged so as to be able to ventilate, the capacitor 11 particularly when a large current flows during charging due to vehicle braking or discharging due to engine start. Temperature rise is suppressed. As a result, the life of the capacitor 11 can be extended and high reliability can be obtained.

  Next, a method for assembling the capacitor unit according to the second embodiment will be described.

  The capacitor 11 is inserted into each holding portion 19 of the right case 40 and the left case 41 in a state where the polarities of the electrodes are aligned in different directions. Thereby, the capacitor 11 is firmly fixed to the right case 40 and the left case 41.

  Next, four female screw rods 42 are arranged at positions corresponding to the four screw holes 38 provided in the right case 40 and the left case 41 (two of them are shown in FIG. 5). The female thread rod 42 has a structure in which a female thread that matches the screw 24 is cut on the entire inside of the cylinder. Therefore, after the female screw rod 42 is disposed, the right case 40 and the left case 41 are tightened into the female screw rod 42 from the screw holes 38 on both sides of the right case 40 and the left case 41, respectively. It is mechanically and firmly fixed via. As a result, both ends of the capacitor 11 are fixed by the holding portions 19 of the right case 40 and the left case 41.

  The assembled state is shown in FIG. The electrodes of each capacitor 11 are arranged in an opening 30 a provided integrally with the right case 40 and the left case 41. Next, the bus bar 30 is fitted into each opening 30a and welded and joined to the electrode to electrically and mechanically connect. The shape of the bus bar 30 and the welding process are the same as in the first embodiment, but in the second embodiment, the bus bar terminal 31 is bent upward at a right angle as shown in FIG. 2 as shown by the dotted line portion in FIG. Without changing the horizontal direction. The front end of the flat cable 45 is connected to the upper side of the bus bar terminal 31 in advance by ultrasonic welding. Thereby, since both can be connected firmly, the reliability of a connection part can be improved.

  As another connection method of the bus bar terminal 31 and the flat cable 45, as shown in FIG. 7, after the caulking portion 31a is integrally formed at the end of the bus bar terminal 31, and the end of the flat cable 45 is inserted into the caulking portion 31a, The bus bar terminal 31 and the flat cable 45 may be connected in advance by caulking. Thereby, although the process of forming the crimping part 31a increases at the time of formation of the bus bar 30, it can connect more easily and firmly than ultrasonic welding, and high reliability is obtained.

  A state where the bus bar 30 is connected is shown in FIG. Next, the power cable 34 is attached with screws 24 to the bus bar 30 connected to the capacitor 11 at both ends of the capacitor unit. Further, after fixing the circuit board 36 to the side surface of the right case 40 by tightening the screw 24 into the boss 28 through the screw hole 38 of the circuit board 36, the tip connected to each bus bar terminal 31 of the flat cable 45 and A female connector 46 connected in advance to the opposite end is fitted into a male connector 47 provided on the circuit board 36 to be electrically connected. This eliminates the need for soldering and enables easy connection. The female connector 46 and the male connector 47 may be attached in reverse.

  The assembled state is shown in FIG. Here, in the second embodiment, the flat cable 45 is used on the assumption that the vibration condition of the vehicle is installed in a severe place. However, when the vibration condition is not so severe, the flat cable 45 is replaced. Alternatively, the flexible cable 39 described in Embodiment 1 may be used.

  The manufacturing method of the capacitor unit having the above configuration is summarized as follows.

  1) The capacitor 11 is held by the holding portion 19 so that the pressure regulating valve 15 is on the upper side and the positioning convex portion 14 is inserted into the fitting portion 21, and is sandwiched between the lower case 18 and the upper case 20.

  2) The flat cable 45 is connected to the bus bar terminal 31 formed integrally with the bus bar 30 in advance.

  3) The bus bar 30 is welded and joined between the electrodes of the adjacent capacitors 11 located in the opening 30a.

  4) The circuit board 36 is fixed to the side surface of the right case 40.

  5) The flat cable 45 and the circuit board 36 are electrically connected.

  In this way, after fixing the capacitor 11, the bus bar 30 is welded and joined, or the bus bar terminal 31 and the circuit board 36 are electrically connected via the flat cable 45 so that no stress is applied to the bus bar 30. The manufacturing method can reduce the influence of stress on the eleventh electrode and obtain high reliability.

  With the above-described configuration and manufacturing method, the capacitor 11 is arranged in the horizontal direction, and can be manufactured without applying stress to the bus bar 30, and the capacitor 11 is firmly fixed by the right case 40 and the left case 41, and the bus bar. Since 30 is firmly fixed to the electrode of the capacitor 11 by welding, a low-profile large-capacity capacitor unit having high reliability was obtained. Furthermore, by adopting the configuration of the second embodiment, since the temperature rise of the capacitor 11 is suppressed, the life is extended, and further high reliability is obtained.

  Note that the type of connection wiring of the capacitor 11 (parallel or series-parallel in addition to series), the number, and the plurality of connections of the capacitor unit may be determined according to the required power specifications as in the first embodiment.

  In the first and second embodiments, the vehicle regeneration system has been described as an example. However, the present invention is not limited to this, and the present invention may be applied to an emergency power source for vehicle emergency or an idling stop.

(Embodiment 3)
FIG. 10 is a partially exploded perspective view when a plurality of capacitor blocks of the capacitor unit according to Embodiment 3 of the present invention are connected.

  In the third embodiment, an example in which a high voltage (a large number of capacitors) is required as in a power storage device for driving a hybrid vehicle will be described. However, the same components as those in the first and second embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  That is, as shown in FIG. 10, the difference from the second embodiment is as follows.

  1) A plurality of capacitors 11 are held in the right case 40 and the left case 41 in the horizontal direction, and adjacent capacitors 11 are electrically connected by a bus bar 30 and connected to a bus bar terminal 31 integrally formed with the bus bar 30. A structure having a cable 45 and one connector (female connector 46 in FIG. 10) connected to the tip thereof, that is, the circuit board 36 from the capacitor unit shown in FIG. 9 of the second embodiment, and a screw for fixing the circuit board 36 The structure in which 24 and the boss 28 are omitted is referred to as a capacitor block 48, and a structure having a plurality of them is provided.

  2) The circuit board 36 is a single board on which a plurality of control circuits for the capacitor blocks 48 and one connector (female connector 46) and the other connector (male connector 47) corresponding to each other are mounted.

  3) The capacitor block connection bus bar 49 is connected to the bus bars 30 at both ends of the adjacent capacitor block 48, and the bus bar 30 at the end of the plurality of capacitor blocks 48, that is, the bus bars at both ends to which the capacitor block connection bus bar 49 is not connected. A power cable 34 was connected to 30.

  4) The female connectors 46 corresponding to the plurality of male connectors 47 were respectively fitted.

  The structure and manufacturing method of the capacitor unit according to the third embodiment will be described focusing on the above differences. Here, an example in which two capacitor blocks 48 are connected in series will be described.

  First, since the structure and manufacturing method of each capacitor block 48 are the same as those in the second embodiment, description thereof will be omitted.

  Next, as shown in FIG. 10, a plurality (two in the present embodiment 3) of capacitor blocks 48 are formed by connecting adjacent bus bars 30 (the bus bars 30 shown in the front in FIG. 10) with capacitor block connection bus bars 49. Connecting. Here, since the capacitor block connection bus bar 49 is provided with two screw holes 38, the screw 24 is inserted into the capacitor block connection bus bar 49 and tightened to the insert nut 27 to be electrically and mechanically connected. The capacitor block connection bus bar 49 has a structure in which a copper surface is subjected to a rust prevention treatment such as plating, and a bent portion 32 is provided at the center, similarly to the bus bar 30. Therefore, resistance can be reduced by using copper, and vibration and tolerance can be absorbed by the bent portion 32.

  Next, the power cable 34 is electrically connected with the screw 24 to the bus bar 30 at the end (not drawn because it is shaded in FIG. 10). In this case, since the bus bar 30 at the endmost part is also adjacent, as shown in FIG. 10, the power cable 34 integrated with the positive and negative lines can be used.

  Next, the capacitor block 48 is stored in the resin outer box 50. At this time, by providing the outer box recess 51 in a part of the outer box 50 and passing the power cable 34 therethrough, the power cable 34 can be taken out even if the outer box cover (not shown) is covered. Although not shown in FIG. 10, the outer box 50 may be provided with a vent at a position corresponding to the exposed portion of the capacitor 11. Thus, heat generation is suppressed by ventilating a large number of capacitors 11, and reliability can be improved.

  Next, the circuit board 36 is inserted and fixed in a circuit board groove 52 formed integrally with the outer box 50, and finally, female connectors 46 corresponding to a plurality of (here, two) male connectors 47 are respectively fitted. By adopting such a configuration, the circuit board 36 attached to each of the capacitor unit structures in the second embodiment can be made into one, so that the space occupied by the circuit board 36 between the capacitor units is not required, and the size can be reduced. In addition, since the number of parts of the entire capacitor unit can be reduced, the failure rate can be reduced and high reliability can be obtained. In addition, since the circuit board 36 is smaller than the side surface area of the right case 40 so as not to face the pressure regulating valve 15, the circuit board 36 should be discharged even if the vaporized electrolyte is discharged from the pressure regulating valve 15. The influence on 36 is reduced, and high reliability is obtained.

  Further, since a plurality of male connectors 47 are provided corresponding to the respective capacitor blocks 48, even if a capacitor block 48 breaks down, the female connector 46 of the capacitor block 48 is disconnected and the capacitor block connection bus bar 49 is connected. It is possible to easily replace the power cable 34 by simply removing the screws 24 fixing the power cable 34, and the effect of improving maintainability can be obtained.

  In the third embodiment, the flat cable 45 is used assuming that the vehicle is installed in a severe vibration condition. However, if the vibration condition is not so severe, the flat cable 45 is used instead. The flexible cable 39 described in Embodiment 1 may be used. However, in this case, it is necessary to connect the flat cable 39 and the circuit board 36 with a connector in order to improve the above-described maintainability.

  The above is the explanation of the difference from the second embodiment, but the other fine structures are the same as those of the second embodiment. Further, the manufacturing method of the third embodiment is the same as the order of 1) to 5) summarized in the second embodiment with respect to the parts other than the above.

  With the above configuration and manufacturing method, a plurality of high-reliability low-profile capacitor blocks 48 are arranged side by side, so that a low-profile large-capacity capacitor unit having high reliability for high-voltage and high-power applications can be obtained. It was.

  In the first to third embodiments, the capacitor 11 has been described as having a cylindrical shape, but is not limited thereto and may have a prismatic shape or the like.

  Also, the connection wiring type (parallel or series-parallel in addition to series) and quantity used for one capacitor block 48, and the connection wiring type and quantity of the plurality of capacitor blocks 48 are the same as in the first and second embodiments. It may be determined according to the required power specification.

  The capacitor unit according to the present invention has a large capacity, can be reduced in height, has a highly reliable configuration, and a manufacturing method. Therefore, the capacitor unit is particularly used for a system or a hybrid system that regenerates braking energy of a vehicle as electric energy. It is useful as a power storage device.

1 is a partially exploded perspective view of a capacitor unit according to Embodiment 1 of the present invention. The perspective view which shows the bus-bar connection of the manufacturing method of the capacitor unit in Embodiment 1 of this invention The perspective view which shows the circuit board of the manufacturing method of the capacitor unit in Embodiment 1 of this invention, and flexible cable attachment The completed perspective view of the capacitor unit in Embodiment 1 of this invention The partial exploded perspective view of the capacitor unit in Embodiment 2 of the present invention The perspective view which shows the bus-bar connection of the manufacturing method of the capacitor unit in Embodiment 2 of this invention The perspective view which shows the connection method by the crimping of the bus-bar terminal of a capacitor unit and the cable in Embodiment 2 of this invention The perspective view which shows the circuit board of the manufacturing method of the capacitor unit in Embodiment 2 of this invention, and flat cable attachment The completed perspective view of the capacitor unit in Embodiment 2 of this invention Partially exploded perspective view when a plurality of capacitor blocks of a capacitor unit in Embodiment 3 of the present invention are connected A perspective view of a conventional backup power supply

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Capacitor 12 Positive electrode 13 Negative electrode 14 Positioning convex part 15 Pressure regulation valve 16 Protrusion part 18 Lower case 19 Holding part 20 Upper case 21 Fitting part 23 Elastic part 24 Screw 28 Boss 30 Bus bar 31 Bus bar terminal 31a Caulking part 32 Bending part 36 Circuit board 39 Flexible cable 40 Right case 41 Left case 45 Flat cable 46 Female connector 47 Male connector 48 Capacitor block 49 Capacitor block connection bus bar 50 Outer box 52 Circuit board groove

Claims (14)

A plurality of capacitors having a cylindrical shape and electrodes provided on both end faces of the cylindrical shape;
A protruding portion in which a part of one of the electrodes of the capacitor protrudes from the cylindrical shape;
A positioning protrusion provided on one of the electrodes of the capacitor;
A pressure regulating valve provided on one of the electrodes of the capacitor;
A bus bar having a shape that exposes the positioning convex part and the pressure regulating valve while connecting the capacitors in series, in parallel, or in series and parallel,
A case in which the pressure regulating valve is exposed and a fitting portion with the positioning convex portion and a holding portion for holding the capacitor in a horizontal direction are integrally formed,
A circuit board having a control circuit for the capacitor,
The capacitor is held by the holding portion so that the pressure regulating valve is on the upper side and the positioning convex portion is inserted into the fitting portion,
Between the electrodes of the adjacent capacitors are welded and joined by the bus bar,
A capacitor unit formed by connecting a bus bar terminal integrally formed with the bus bar and the circuit board disposed on a side surface of the case by a cable. The capacitor unit according to claim 1, wherein the holding portion has an elastic portion arranged so as to contact the capacitor. The capacitor unit according to claim 1, wherein the holding portion is provided only on both electrode sides of the capacitor, and the case is configured so that a central portion of the capacitor is exposed. The capacitor unit according to claim 1, wherein the circuit board is smaller than the case and has a shape that does not face the pressure regulating valve. The capacitor unit according to claim 1, wherein the cable is a flexible cable or a flat cable. The capacitor unit according to claim 1, wherein a bent portion is provided in a part of the bus bar. The capacitor unit according to claim 1, wherein the circuit board is fixed to a boss integrally formed with the case with a screw. A plurality of capacitor blocks configured by holding a plurality of capacitors in the case in the horizontal direction and electrically connecting the adjacent capacitors with a bus bar;
A cable connected to a bus bar terminal integrally formed with the bus bar for each capacitor block;
One connector connected to the tip of the cable;
Each of the capacitor blocks has a control circuit, and includes a circuit board on which a plurality of other connectors corresponding to the one connector are mounted,
A capacitor block connection bus bar is connected to the bus bars at both ends of the adjacent capacitor blocks, and a power cable is connected to the bus bar at the end of the plurality of capacitor blocks, and the other one corresponding to the one connector Capacitor unit with each connector fitted. The capacitor unit according to claim 8, wherein a bent portion is provided in a part of the capacitor block connection bus bar. The capacitor unit according to claim 8, wherein the plurality of capacitor blocks are housed in an outer box, and the circuit board is inserted and fixed in a circuit board groove formed integrally with the outer box. A plurality of capacitors having a cylindrical shape and electrodes provided on both end faces of the cylindrical shape;
A protruding portion in which a part of one of the electrodes of the capacitor protrudes from the cylindrical shape;
A positioning protrusion provided on one of the electrodes of the capacitor;
A pressure regulating valve provided on one of the electrodes of the capacitor;
A bus bar having a shape that exposes the positioning convex part and the pressure regulating valve while connecting the capacitors in series, in parallel, or in series and parallel,
A case in which the pressure regulating valve is exposed and a fitting portion with the positioning convex portion and a holding portion for holding the capacitor in a horizontal direction are integrally formed,
A circuit board having a control circuit for the capacitor,
After holding the capacitor in the holding portion so that the pressure regulating valve is on the upper side and the positioning convex portion is inserted into the fitting portion,
Welding the electrodes of the adjacent capacitors with the bus bar,
Next, after fixing the circuit board to the side of the case,
A method of manufacturing a capacitor unit, wherein a bus bar terminal formed integrally with the bus bar and the circuit board are electrically connected by a cable. A plurality of capacitors having a cylindrical shape and electrodes provided on both end faces of the cylindrical shape;
A protruding portion in which a part of one of the electrodes of the capacitor protrudes from the cylindrical shape;
A positioning protrusion provided on one of the electrodes of the capacitor;
A pressure regulating valve provided on one of the electrodes of the capacitor;
A bus bar having a shape that exposes the positioning convex part and the pressure regulating valve while connecting the capacitors in series, in parallel, or in series and parallel,
A cable connected to a bus bar terminal formed integrally with the bus bar;
A case in which the pressure regulating valve is exposed and a fitting portion with the positioning convex portion and a holding portion for holding the capacitor in a horizontal direction are integrally formed,
A circuit board having a control circuit for the capacitor,
After holding the capacitor in the holding portion so that the pressure regulating valve is on the upper side and the positioning convex portion is inserted into the fitting portion,
Welding the electrodes of the adjacent capacitors with the bus bar,
Next, after fixing the circuit board to the side of the case,
A method of manufacturing a capacitor unit for electrically connecting the cable to the circuit board. The method of manufacturing a capacitor unit according to claim 12, wherein the bus bar terminal and the cable are connected by ultrasonic welding. 13. The method of manufacturing a capacitor unit according to claim 12, wherein a caulking portion is integrally formed at a front end of the bus bar terminal, and the bus bar terminal and the cable are connected by caulking after the cable is inserted into the caulking portion.

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