JPH08288187A - Capacitor - Google Patents

Abstract

PURPOSE: To provide an electrolytic capacitor where a capacitor element is not inclined even if a shock or vibration is given and is not short-circuited even if an abnormal stress in applied. CONSTITUTION: In an electrolytic capacitor 1, a capacitor element 3 (two sheets of electrolytic paper with an electrode foil are overlapped and wound) is encased in a cylindrical case 4, the opening of the case 4 is sealed by a hole sealing plate 6, and the bottom side of the capacitor element 3 is fixed by a fixing agent 5. The capacitor element 3 is provided with a spool 2 made of aluminum at a winding center and the spool 2 is pressed to the bottom of the case 4 and the hole sealing plate 6 for fixing. In this manner, since the capacitor element 3 is fixed and supported by the spool 2 even at the opening side of the case 4, the capacitor element 3 is not inclined even if a vibration or shock is applied. Also, even if the capacitor element 3 is subjected to such an abnormal stress as overvoltage and inner pressure increase, the spool 2 is arranged at the winding center, thus preventing the deformation of the winding center of the capacitor element 3 and short-circuiting.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radial type capacitor in which an opening is closed with a sealing plate after a capacitor element is housed in a bottomed container-like case, which is particularly suitable for use as an electrolytic capacitor. In addition, it is suitable for application to capacitors for vehicles, which are required to have vibration resistance.

[0002]

2. Description of the Related Art The structure of a conventional radial type electrolytic capacitor is shown in FIG. The electrolytic capacitor 100 includes a capacitor element 101 formed by sandwiching an anode foil and a cathode foil with paper (electrolytic paper) impregnated with an electrolytic solution, a cylindrical case 102 having a bottomed container shape, and closing an opening of the case 102. Seal plate 10
It consists of 3. Then, the fixing means of the capacitor element 101 is to inject the melted fixing agent 104 (resin such as paraffin and pitch) into the case 102, and then the case 1
02, the capacitor element 101 is inserted, and the fixing agent 104
The means to solidify is adopted.

[0003]

The capacitor 100 is composed of
The internal temperature rises during use. Then, the internal pressure rises due to the evaporation of the electrolytic solution or the like, so that a space is needed in the case 102 to absorb and absorb the rise in the internal pressure. Therefore, in order to form a space in the case 102, the fixative 1
Reference numeral 04 denotes the case 102 from the bottom of the capacitor element 101.
Can only be filled at 1/4 to 1/3 of the height.

As described above, since the capacitor element 101 is fixedly supported only on the bottom side, the fixing force on the opening side is weak. Therefore, the capacitor 10
When 0 receives a shock or vibration, the capacitor element 101
May tilt, causing a problem in which the tab lead 105 is overloaded, and the tab lead 105 may be cut in some cases.

The winding center of the capacitor element 101 is attached to the core of the winding machine during the manufacturing process.
After winding 01, the core is removed from the capacitor element 101, so that the core is an empty core as shown in FIG. Therefore, the capacitor element 101 is overvoltage,
When abnormal stress such as an increase in internal pressure is applied, the capacitor element 101 may expand toward the winding center (air core) as shown in FIG. 11B. When the capacitor element 101 expands toward the winding center (air core) in this way, the electrode foil or the electrolytic paper may be broken and the anode foil and the cathode foil may be short-circuited.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to prevent the capacitor element from tilting in the case even if it is subjected to shock, vibration, etc. The purpose is to provide a capacitor that does not cause a short circuit.

[0007]

The capacitor of the present invention comprises:
The following technical measures were adopted. [Means for Claim 1] The capacitor comprises: a) a film-shaped first dielectric having a first electrode foil provided on one surface, and a film-shaped second dielectric having a second electrode foil provided on one surface. A capacitor element in which dielectrics are overlapped and wound; b) a rod-shaped core body provided so as to penetrate through the winding center of this capacitor element; and c) a bottomed container shape for accommodating the capacitor element equipped with this core body. A case; and d) a sealing plate that closes the opening of the case and fixes one end of the core body.

[Means for Claim 2] In the capacitor according to claim 1, the core is made of a material having excellent thermal conductivity.

[Means for Claim 3] In the capacitor of claim 1 or 2, the core body is a winding core around which the first dielectric body and the second dielectric body are wound.

[Means of claim 4] In the capacitor of claim 3, the winding core is provided with a slit along the axial direction,
The winding start ends of the first dielectric and the second dielectric are inserted into the slit.

[Means of Claim 5] In the capacitor of claim 3, the winding core is a divided body that can be divided along the axial direction, and the divided body is divided into the first dielectric body and the second dielectric body. It is characterized in that the winding start end is sandwiched.

[Means of Claim 6] In the capacitor according to any one of Claims 1 to 5, in the fixing portion between the core and the sealing plate, the core is inserted into the sealing plate. It is characterized by

[Means for Claim 7] In the capacitor according to any one of claims 1 to 5, the winding core and the sealing plate are integrally provided.

[0014]

Action of the Invention and Effect of the Invention

[Operation and effect of claim 1] In the capacitor of claim 1, since one end of the core body that penetrates the winding center of the capacitor element is fixed to the sealing plate, even if vibration or impact is applied to the capacitor, the sealing is performed. The core fixed to the plate does not tilt, and as a result, the capacitor element does not tilt in the case. In other words, even if vibration or shock is applied to the capacitor,
The capacitor element does not tilt in the case, the tab lead is not burdened, and the tab lead can be prevented from being broken.

Further, since the core body is disposed so as to penetrate through the winding center of the capacitor element, the deformation of the winding center of the capacitor element can be prevented even if abnormal stress such as overvoltage or increase in internal pressure is applied to the capacitor element. it can. Further, since the deformation of the winding center of the capacitor element due to the application of the abnormal stress is prevented, it is possible to suppress the defect that the first electrode foil and the second electrode foil are short-circuited due to the deformation.

[Operation and Effect of Claim 2] In the capacitor of claim 2, since the core has excellent thermal conductivity, the heat at the winding center of the capacitor element can be transferred to the sealing plate. Therefore, it is possible to dissipate heat at the winding center of the capacitor element, which has been difficult in the past, and it is possible to suppress the temperature at the winding center of the capacitor element. Since the temperature at the winding center of the capacitor element can be suppressed in this way,
When the ripple current is applied to the capacitor element, the temperature rise at the winding center is suppressed, and as a result, a larger ripple current can be passed as compared with the conventional case.

[Operation and Effect of Claim 3] Since the core body of the capacitor of claim 3 uses the core around which the first dielectric body and the second dielectric body are wound, the core body is easy to manufacture and is empty. The manufacturing cost can be reduced as compared with the case where the core body is inserted into the core.

[Operation and Effect of Claim 4] Since the winding core (core body) of the capacitor according to claim 4 has a slit for inserting the winding start end portions of the first dielectric body and the second dielectric body,
The work of winding the first dielectric and the second dielectric becomes easy.

[Operation and Effect of Claim 5] The winding core (core body) of the capacitor according to claim 5 is provided in a divided manner.
Since the winding start ends of the dielectric body and the second dielectric body are sandwiched, the winding work of the first dielectric body and the second dielectric body becomes easy.

[Operation and Effect of Claim 6] The capacitor according to claim 6 adopts a structure in which the core is inserted into the sealing plate, so that the assembly is easy and the sealing plate is surely the end part of the core. Can be fixed.

[Operation and Effect of Claim 7] The capacitor according to claim 7 adopts a structure in which the core body is provided integrally with the sealing plate, so that the number of parts is reduced and the sealing plate is surely the core body. The ends can be fixed.

[0022]

EXAMPLES Next, the capacitors of the present invention will be described based on the examples shown in the drawings. [Structure of First Embodiment] FIGS. 1 to 7 show a first embodiment of the present invention. FIG. 1 is a sectional view of an electrolytic capacitor. The electrolytic capacitor 1 includes a capacitor element 3 wound around a winding core 2, a cylindrical case 4 having a bottom, a fixing agent 5, a sealing plate 6, an anode terminal 7, a cathode terminal 8 and an insulating sleeve 9.

The winding core 2 is a core that penetrates through the winding center of the capacitor element 3, and is made of a material having a high mechanical strength and excellent thermal conductivity (for example, aluminum) formed in a cylindrical shape ( (See FIG. 3).

The capacitor element 3 is, as shown in FIG.
The anode foil 12a (corresponding to the first electrode foil) to which the tab lead 11a for taking out the anode is attached is superposed on one surface (or vapor-deposited) of the first electrolytic paper 13a and the tab lead 11b for taking out the cathode. Attached cathode foil 1
2b (corresponding to the second electrode foil) is superposed on one surface of the second electrolytic paper 13b (or evaporated), and is wound around the core 2. In addition,
The first electrolytic paper 13a and the second electrolytic paper 13b are electrolytic papers impregnated with an electrolytic solution.

The core 2 has first and second electrolytic papers 13a and 13b.
An example of a means for winding is shown below. (A) As shown in FIG. 3, the ends of the first and second electrolytic papers 13a and 13b are fixed to the circumference of the cylindrical winding core 2 with a tape 14, and the first and second electrolytic papers are wound around the winding core 2. Wrap the paper 13a, 13b. (B) As shown in FIG. 4, the cylindrical core 2 is provided with the slit 15 along the axial direction. Then, the ends of the first and second electrolytic papers 13a and 13b are inserted into the slits 15 of the winding core 2. Next, the slits 15 into which the first and second electrolytic papers 13a and 13b are inserted are caulked, and the first and second slits 15 are formed around the winding core 2.
The electrolytic papers 13a and 13b are wound.

(C) As shown in FIG. 5, a cylindrical winding core 2
A slit 15 is provided along the axial direction. Then, in the slit 15 of the winding core 2, the first and second electrolytic papers 13a and 13b are provided.
Insert the end of. Next, the first and second electrolytic papers 13a and 13
The first and second electrolytic papers 13 are formed around the winding core 2 into which b is inserted.
Wrap a and 13b. (D) As shown in FIGS. 6 and 7, the cylindrical winding core 2 is provided so as to be divided into two along the axial direction. Then, the ends of the first and second electrolytic papers 13a and 13b are sandwiched between the two divided bodies 16a and 16b. Next, the first and second electrolytic papers 13a and 13b are wound around the winding core 2 in which the first and second electrolytic papers 13a and 13b are sandwiched.

The case 4 is a cylindrical bottomed container for accommodating the capacitor element 3 wound around the winding core 2, and is made of a material having high mechanical strength and excellent thermal conductivity (for example, aluminum).
Consists of.

The fixing agent 5 is a resin (paraffin, pitch, etc.) for fixing the capacitor element 3 housed in the case 4 on the bottom side of the case 4, and the fixing means is a fixing agent melted in the case 4. 5, the capacitor element 3 was inserted into the case 4, and the fixative 5 was solidified.

The sealing plate 6 is a lid for tightly hermetically sealing the opening of the case 4 accommodating the capacitor element 3 and fixing one end of the winding core 2 in the case 4, and is made of an insulating material having high mechanical strength. Consists of. The sealing plate 6 of this embodiment is the case 4
The core 2 is pressed into the case 4 when the opening of the core 2 is sealed, and the core 2 is pressed against the bottom of the case 4 and the sealing plate 6, so that the core 2 is inserted into the case 4. It is firmly fixed.

In this embodiment, the core 2 is fixed in the case 4 by pressurizing the core 2 between the bottom of the case 4 and the sealing plate 6, but the sealing plate 6 has an end of the core 2. It is also possible to provide a concave portion (fixing portion) into which the portion is inserted, and insert the end portion of the winding core 2 into the concave portion to fix the opening-side end portion of the winding core 2 inside the case 4. Alternatively, the core 2 and the sealing plate 6 may be integrally provided to fix the end of the core 2 on the opening side in the case 4.

The anode terminal 7 is a connection terminal firmly fixed to the sealing plate 6, and is electrically connected to the tab lead 11a for taking out the anode of the capacitor element 3 in the case 4. The cathode terminal 8 is also a connection terminal firmly fixed to the sealing plate 6, and is electrically connected to the tab lead 11b for taking out the cathode of the capacitor element 3 in the case 4.

The insulating sleeve 9 is made of an insulating material such as resin that covers the case 4 and insulates the case 4 from the outside.
On the surface, capacity, pressure resistance, etc. are printed.

[Operation and Effect of Embodiment] Next, the effect of the above embodiment will be described together with the operation. In the electrolytic capacitor 1 of this embodiment, both ends of the winding core 2 and the bottom of the case 4 and the sealing plate 6 are provided.
And the capacitor element 3 is fixed by the fixing agent 5 on the bottom side of the case 4.
Therefore, even if a relatively large vibration or shock is applied to the electrolytic capacitor 1, the winding core 2 does not tilt in the case 4, and as a result, the capacitor element 3 also does not tilt in the case 4.

As described above, even if a relatively large vibration or shock is applied to the electrolytic capacitor 1, the capacitor element 3 does not tilt in the case 4, so that the tab leads 11a and 11b are not formed.
Therefore, the tab lead 11a, 11b is prevented from being cut off. Therefore, it is most suitable for use in an electrolytic capacitor 1 that is subject to vibration, particularly a capacitor for an automobile (for example, a smoothing capacitor for an inverter for an electric vehicle).

Further, at the winding center of the capacitor element 3,
Since the winding core 2 is arranged so as to penetrate therethrough, the deformation of the winding center of the capacitor element 3 can be prevented even if abnormal stress such as overvoltage or increase in internal pressure is applied to the capacitor element 3. in this way,
Even if abnormal stress is applied, the deformation of the winding center of the capacitor element 3 is prevented, so that the anode foil 12a and the cathode foil 12 are not deformed.
It is possible to suppress the problem of short-circuiting with b due to deformation.

Further, since the winding core 2 is excellent in thermal conductivity,
The heat at the winding center of the capacitor element 3 can be transferred to the sealing plate 6. For this reason, it is possible to radiate heat at the winding center of the capacitor element 3, which has been difficult in the past, and suppress the temperature at the winding center of the capacitor element 3. Since the temperature at the winding center of the capacitor element 3 can be suppressed in this way, the increase in internal pressure is suppressed and the temperature increase at the winding center when a ripple current is applied to the capacitor element 3 is suppressed. In comparison, a larger ripple current can be passed as compared with the conventional one.

[Second Embodiment] FIG. 8 is a sectional view of an electrolytic capacitor 1 showing a second embodiment. The electrolytic capacitor 1 of the present embodiment is provided with a pressing protrusion 21 protruding toward the inside of the case 4 in the central portion of the inside of the case 4 of the sealing plate 6.
The pressing protrusion 21 presses the opening-side end of the winding core 2 toward the bottom of the case 4.

In this way, the pressing projection 2 provided on the sealing plate 6
By adopting the structure in which the winding core 2 is pressed by 1, the axial dimension of the winding core 2 can be shortened as compared with the first embodiment.
Therefore, since the strength of the winding core 2 is improved, the vibration resistance of the electrolytic capacitor 1 is further improved as compared with the first embodiment.

[Third Embodiment] FIG. 9 is a sectional view of an electrolytic capacitor 1 according to a third embodiment. The electrolytic capacitor 1 of the present embodiment is provided with a recess 22 (fixing part) into which the bottom end of the winding core 2 is inserted, in the center of the bottom of the case 4.
The bottom end of the winding core 2 is fixed in the case 4 by inserting the end of the winding core 2 therein.

By thus forming the recess 22 in the bottom of the case 4 and inserting the bottom end of the winding core 2, the winding core 2 can be easily positioned on the bottom side of the case 4 and the bottom of the case 4 can be easily positioned. It is possible to reliably prevent the winding core 2 from being displaced on the side. As a result, the vibration resistance of the electrolytic capacitor 1 is further improved.

[Modification] In the above embodiment, the first and second
Although an electrolytic capacitor using electrolytic paper as the dielectric is shown as an example, it may be applied to other capacitors using oil paper, metallized paper, resin film or the like as the first and second dielectrics. In the above embodiment, an example in which the winding core is used as the core body is shown, but a rod-shaped core body may be inserted later at the winding center (air core) of the existing capacitor element provided in the air core. .

[Brief description of drawings]

FIG. 1 is a sectional view of an electrolytic capacitor (first embodiment).

FIG. 2 is an explanatory diagram of a capacitor element (first embodiment).

FIG. 3 is an explanatory view of winding first and second electrolytic papers around a winding core.

FIG. 4 is an explanatory view of winding first and second electrolytic papers around a winding core.

FIG. 5 is an explanatory diagram of winding first and second electrolytic papers around a winding core.

FIG. 6 is an explanatory view of winding first and second electrolytic papers around a winding core.

FIG. 7 is an explanatory diagram of winding first and second electrolytic papers around a winding core.

FIG. 8 is a sectional view of an electrolytic capacitor (second embodiment).

FIG. 9 is a sectional view of an electrolytic capacitor (third embodiment).

FIG. 10 is a cross-sectional view of an electrolytic capacitor (prior art).

FIG. 11 is a top view of a capacitor element showing a problem of abnormal stress (prior art).

[Explanation of symbols]

 1 Electrolytic Capacitor 2 Core (Core) 3 Capacitor Element 4 Case 6 Sealing Plate 12a Anode Foil (First Electrode Foil) 12b Cathode Foil (Second Electrode Foil) 13a First Electrolytic Paper (First Dielectric) 13b Second Electrolytic paper (second dielectric) 15 Slit 16a Divided body 16b Divided body

Claims (7)

[Claims] 1. A) A film-shaped first dielectric material having a first electrode foil provided on one surface, and a film-shaped second dielectric material having a second electrode foil provided on one surface. A wound capacitor element; b) a rod-shaped core body provided so as to penetrate through the winding center of the capacitor element; c) a bottomed container-like case for accommodating the capacitor element having the core body; and d) A capacitor including a sealing plate that closes an opening of the case and fixes one end of the core body. 2. The capacitor according to claim 1, wherein the core body is made of a material having excellent thermal conductivity. 3. The capacitor according to claim 1 or 2, wherein the core body is a winding core around which the first dielectric body and the second dielectric body are wound. 4. The capacitor according to claim 3, wherein the winding core has a slit along the axial direction, and the winding start end portions of the first dielectric body and the second dielectric body are inserted into the slit. And the capacitor. 5. The capacitor according to claim 3, wherein the winding core is a divided body that can be divided along an axial direction, and the winding start ends of the first dielectric body and the second dielectric body are formed in the divided body. A capacitor characterized by being sandwiched. 6. The capacitor according to claim 1, wherein a fixing portion between the winding core and the sealing plate has the winding core inserted in the sealing plate. Capacitor to do. 7. The capacitor according to claim 1, wherein the winding core and the sealing plate are integrally provided.