JP4460415B2 - Metallized film capacitors - Google Patents

Description

  The present invention relates to a metallized film capacitor element or capacitor element unit that is housed in a case and connected and filled with a resin, and in particular, improves the reliability and stability of the mounting structure. The present invention relates to a metallized film capacitor.

Conventionally, a metallized film capacitor consisting of a capacitor element or capacitor element unit wound with a metallized film is connected by soldering the lead wire of the capacitor element to the connecting wire or by soldering to the copper plate for connection. It was.
For example, as shown in FIGS. 5 and 6, there is one in which a connecting wire is soldered to a lead wire of a capacitor element assembly (see, for example, Patent Document 1).
However, in the metallized film capacitor having the above configuration, there is a problem in reliability because peeling of the solder occurs due to vibration or the like.

In addition, as shown in FIGS. 7 and 8, as the capacitor mounting structure, there is one in which two or more capacitor bodies are fixed by pressing them against the base via a common press fitting (for example, Patent Document 2). reference).
However, this structure has a problem that the member cost is increased, the structure becomes complicated and it takes time to mount, and the structure easily swings with respect to the force in the direction of the arrow in FIG.
JP 2001-60529 A Japanese Utility Model Publication No. 5-48327

  Due to the above-mentioned problems, when the capacitor unit is configured by connecting capacitor elements, there is no peeling of solder due to vibration of the metalized film capacitor, etc., which can improve reliability, low cost, simple and stable What was needed was a structure.

The present invention solves the above-mentioned problem, and a metallized film formed by connecting a plurality of elements wound with a metallized film, each stored in a plastic case and filled with a resin. In the capacitor, the plurality of capacitor elements constitute a capacitor element unit divided into a plurality of capacitor element aggregates, and the capacitor element unit is housed in a metal case in a state in which an enclosed gas is sealed, Each of the capacitor element aggregates is fixed to the upper surface with a metal plate for connecting lead wires derived from the capacitor elements constituting the capacitor element aggregate to each other with solder, and a first through hole is formed. The capacitor element assemblies are stacked in a state having a plastic plate and sandwiching the first plastic plate. A second plastic plate to which a metal plate is not fixed is disposed on the bottom surface of the capacitor element assembly, and the first plastic plate and the second plastic plate are inserted into the insertion hole. A metallized film capacitor characterized by being fixed through a rod .

Further, the first and second plastic plates are made of polypropylene resin, epoxy-phenol resin, phenol resin, polyester resin, polybutylene terephthalate resin, and the first plastic plate and metal plate are fixed with rivets. This is a metallized film capacitor.

  The metallized film capacitor is characterized in that the metal plate is made of copper, aluminum, or brass, and the metal plate is tin-plated.

  The metalized film capacitor is characterized in that the metal plate and the lead wire are connected by soldering.

In the metallized film capacitor, the first and second plastic plates have a thickness of 1.5 to 5.0 mm, and the metal plate has a thickness of 0.1 to 0.7 mm. is there.

A capacitor element assembly is configured by connecting lead wire soldering of a plurality of capacitor elements (plastic case storage, resin filling) around which a metallized film is wound to a metal plate fixed in advance to a plastic plate. The capacitor element assembly can be fixed by arranging the body in multiple stages and fixing with a plastic plate (with and without metal plate), a fixing rod, and a screw. The solder does not peel off between the metal plate and the lead wire due to vibration or the like, and the reliability can be improved.
In addition, this structure can reduce the member cost, can provide a stable metalized film capacitor against vibrations in the vertical, horizontal, and horizontal directions because the structure is simple and does not take time to mount. .

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[Examples 1 to 6]
FIG. 1 (a) is a plan view of a plastic plate 4 used in an embodiment of the present invention, in which a copper plate is pre-plated with tin and the copper plate 1 is fixed with rivets 5. FIG. FIG.
A plastic plate made of polypropylene resin was used.
As shown in the perspective view of FIG. 2A, the position of the lead wire 2 led out from six capacitor elements 3 (234 V, 50 μF, 7 μm metallized polypropylene film winding) is used using the plastic plate 4 described above. In addition, the lead wire was soldered and connected with the copper plate 1 (tin plating treatment) fixed to the plastic plate 4, and the capacitor element 3 a was fixed with the plastic plate 4 to constitute the capacitor element assembly 3 b. Here, FIG. 2B is a side view of the capacitor element assembly of FIG.
As shown in FIG. 3A, the capacitor element assembly has two stages, a plastic plate 9 without a metal plate is stacked on the bottom surface of the lower stage, and screws are fixed by screw holes 6a of the plastic plate via fixing rods 17, thereby the capacitor element unit. Then, after connecting the metal plates of the upper and lower capacitor assemblies and storing them in the metal case 7, nitrogen gas is sealed in order to remove moisture and oxygen, and the rating: 234V, 1800 μF metallized film capacitor (capacitor element) A total of 36) was assembled for each condition shown in Table 1.
Here, FIG. 3A is a front view when the capacitor element assembly of FIG. 2A is arranged in the state of FIG. 2B when viewed from the A direction, and a rectangular dotted line portion is shown in FIG. This corresponds to the capacitor element assembly 3b of (b).
In FIG. 3A, the connection body of the external terminals (U, V, W) and the capacitor element assembly is as shown in FIG. Further, the external terminals (U, V, W) and the capacitor element assembly are screw-fixed.
3A, the capacitor element assembly is surrounded by a heat-resistant polyimide film 27, and between the polyimide films 27 and between the polyimide film 27 and the metal case 7, A plate 28 is inserted.
The plastic plate thickness was 1.0 to 8.0 mm, the copper plate thickness was fixed at 0.3 mm, and the optimum thickness of the plastic plate was examined.

[Examples 7 to 10]
In the same manner as in Examples 1 to 6, a capacitor element unit was constructed, housed in a metal case, filled with urethane resin, and a metallized film capacitor with a rating of 234 V and 1800 μF was prepared for each condition shown in Table 1. Assembled one by one.
The plastic plate thickness was fixed at 2.0 mm, the copper plate thickness was 0.05 to 1.0 mm, and the optimum thickness of the copper plate was examined.

(Conventional example)
As shown in FIG. 4, the capacitor elements similar to the above Examples 1 to 10 are not fixed with a plastic plate, and only a copper plate having a thickness of 0.3 mm is used and soldered to form a capacitor element assembly. (Corresponding to FIG. 7).
The above capacitor element assemblies were stacked in two stages, housed in a metal case, filled with urethane resin, and 10 metallized film capacitors rated at 234 V and 1800 μF were assembled.

A vibration resistance test was performed on the metallized film capacitors of Examples 1 to 10 and the conventional example manufactured as described above. Based on JIS E 4031 (Type 2B test), the test conditions were: frequency: 10 Hz, amplitude: 3.5 mm, 1.4 G, X and Y directions: 2 hours each, Z direction: 4 hours.
The results are shown in Table 1.

As is clear from Table 1, the capacitor element lead wires are connected by a copper plate fixed to a plastic plate to form a capacitor element assembly, and are arranged at the upper and lower stages, and the capacitor element is pressed by the plastic plate. In the fixed example, since the capacitor element is firmly fixed, an increase in the dielectric loss tangent (tan δ [%]) in the vibration resistance test is suppressed, and it can be seen that the reliability is improved.
However, in the conventional example in which the capacitor element unit is configured by connecting only with a copper plate without being fixed by a plastic plate, the capacitor element (plastic case storage) oscillates during a vibration resistance test, so that the dielectric loss tangent (tan δ [%]) ) Is increasing significantly.
Here, the thickness of the copper plate is suitably in the range of 0.1 to 0.7 mm. If it is less than 0.1 mm, the soldering strength becomes weak, and if it exceeds 0.7 mm, the step with the plastic plate becomes large, and the pressing of the capacitor element by the plastic plate becomes insufficient.
The thickness of the plastic plate is suitably in the range of 1.5 to 5.0 mm. If it is less than 1.5 mm, the warp under high temperature becomes large, and if it exceeds 5.0 mm, the product height becomes large, which is not preferable.

In the above embodiment, polypropylene resin is used for the plastic plate, but the same effect can be obtained even when epoxy-phenol resin, phenol resin, polyester resin, or polybutylene terephthalate resin is used.
Moreover, in the said Example, although the copper plate was used as a metal plate fixed to a plastic plate, you may use aluminum and brass other than this.
And in the said Example, although the capacitor | condenser assembly was piled up in two steps, the same effect is acquired even if it makes it three or more steps.

FIG. 1A is a plan view of a plastic plate used in the capacitor element assembly of the present invention, in which a copper plate is fixed with rivets, and FIG. 1B is a cross-sectional view thereof. 2A is a perspective view of the capacitor element assembly fixed by the plastic plate of FIG. 1, and FIG. 2B is a front view of the capacitor element assembly viewed from the direction A in FIG. 2A. It is. FIG. 3A is a front view of the metallized film capacitor according to the embodiment of the present invention in which the front part of the case is removed, and FIG. 3B is a state diagram when the capacitor element assembly is connected. It is. It is a perspective view of the capacitor | condenser element assembly used for the metallized film capacitor of a prior art example. It is a front view of the state which removed the case front part of the metallized film capacitor by other conventional examples. It is a longitudinal cross-sectional view of the capacitor | condenser element assembly which comprises FIG. It is a top view of the capacitor unit by other conventional examples. FIG. 8 is a side view of the capacitor unit of FIG. 7.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Copper plate 2 Lead wire 3a Capacitor element 3b Capacitor element aggregate 3c Metallicon part 4 Plastic plate (copper plate attachment)
4a hole (for lead wire installation work)
5 Rivet 6a Screw hole 6b, 6c Screw 7 Metal case 8a, 8b Connecting wire 9 Plastic plate (without copper plate)
DESCRIPTION OF SYMBOLS 10 Fixing resin 11a Lead wire 11b External terminal 11c Screw part 12 Insulating gas 13a, 13b Nut 14 Insulating plate 15 Insulating film 16 Through hole 16a Insulating rod 17 Fixing rod 18 Insulating resin 19 Holding metal 20a, 20b Conductor plate 21 Capacitor 22 Base 23 Substrate 24 Mounting base 25a Screw hole 25b Screw 26 Insulator 27 Polyimide film 28 Mica plate 29 Connection line 30 Connection line stopper

Claims (5)

In a metallized film capacitor formed by connecting a plurality of capacitor elements filled with resin by storing an element wound with a metallized film in a plastic case,
The plurality of capacitor elements constitute a capacitor element unit divided into a plurality of capacitor element aggregates,
The capacitor element unit is housed in a metal case in a state where a sealed gas is sealed,
Each of the plurality of capacitor element aggregates has a metal plate for connecting lead wires derived from the capacitor elements constituting the capacitor element aggregate to each other with solder on the surface, and an insertion hole is formed in the upper stage. Having a first plastic plate,
The capacitor element assemblies are stacked in a state where the first plastic plate is sandwiched between them,
A second plastic plate to which a metal plate is not fixed is disposed on the bottom surface of the stacked capacitor element assembly;
The metallized film capacitor, wherein the first plastic plate and the second plastic plate are fixed via a fixing rod inserted through the insertion hole . The first and second plastic plates according to claim 1 are made of polypropylene resin, epoxy-phenol resin, phenol resin, polyester resin, or polybutylene terephthalate resin, and the first plastic plate and metal plate are fixed with rivets. A metallized film capacitor characterized by being made. 2. A metallized film capacitor according to claim 1 , wherein the metal plate is made of copper, aluminum, or brass, and the metal plate is tin-plated . A metallized film capacitor, wherein the metal plate according to claim 1 and a lead wire are connected by soldering . 2. The metallized film according to claim 1, wherein the first and second plastic plates have a thickness of 1.5 to 5.0 mm, and the metal plate has a thickness of 0.1 to 0.7 mm. Capacitor.

Images