JP3697560B2 - Radiator - Google Patents
Radiator Download PDFInfo
- Publication number
- JP3697560B2 JP3697560B2 JP29094895A JP29094895A JP3697560B2 JP 3697560 B2 JP3697560 B2 JP 3697560B2 JP 29094895 A JP29094895 A JP 29094895A JP 29094895 A JP29094895 A JP 29094895A JP 3697560 B2 JP3697560 B2 JP 3697560B2
- Authority
- JP
- Japan
- Prior art keywords
- hollow plate
- heat pipe
- working fluid
- heating element
- heat
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 238000005192 partition Methods 0.000 claims description 20
- 238000010438 heat treatment Methods 0.000 claims description 18
- 239000012530 fluid Substances 0.000 claims description 16
- 229910052782 aluminium Inorganic materials 0.000 claims description 14
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 14
- 239000000463 material Substances 0.000 claims description 2
- 238000000638 solvent extraction Methods 0.000 claims description 2
- 230000005855 radiation Effects 0.000 description 5
- 238000001816 cooling Methods 0.000 description 2
- 230000017525 heat dissipation Effects 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 229910000838 Al alloy Inorganic materials 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 230000000149 penetrating effect Effects 0.000 description 1
- 239000004065 semiconductor Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
- F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
- F28D15/0233—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes the conduits having a particular shape, e.g. non-circular cross-section, annular
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F28—HEAT EXCHANGE IN GENERAL
- F28D—HEAT-EXCHANGE APPARATUS, NOT PROVIDED FOR IN ANOTHER SUBCLASS, IN WHICH THE HEAT-EXCHANGE MEDIA DO NOT COME INTO DIRECT CONTACT
- F28D15/00—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies
- F28D15/02—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes
- F28D15/0266—Heat-exchange apparatus with the intermediate heat-transfer medium in closed tubes passing into or through the conduit walls ; Heat-exchange apparatus employing intermediate heat-transfer medium or bodies in which the medium condenses and evaporates, e.g. heat pipes with separate evaporating and condensing chambers connected by at least one conduit; Loop-type heat pipes; with multiple or common evaporating or condensing chambers
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Cooling Or The Like Of Semiconductors Or Solid State Devices (AREA)
- Cooling Or The Like Of Electrical Apparatus (AREA)
Description
【0001】
【発明の属する技術分野】
この発明は放熱器、さらに詳しくは、たとえばトランジスタ、サイリスタ等の半導体素子の熱を放熱するための放熱器に関する。
【0002】
【従来の技術】
従来、この種放熱器として、片面に発熱体取付部を有する金属板の上面に放熱フィンが固着されたものが知られている(実公昭62−23091号参照)。
【0003】
【発明が解決しようとする課題】
しかしながら、従来の放熱器においては、発熱体の熱は、金属板を介して放熱フィンに伝わるだけであり、フィンの上側部分が、十分に放熱の役割を果たしていない。したがって、放熱性能が十分ではないという問題があった。
【0004】
この発明の目的は、上記問題を解決し、放熱性能が向上した放熱器を提供することにある。
【0005】
【課題を解決するための手段】
請求項1の発明による放熱器は、相対向する2つの中空板状部、および両中空板状部を相互に連結する中空連結部を有するコ字状ヒートパイプと、ヒートパイプにおける相対向する中空板状部間に配され、かつ両中空板状部に接した状態で固着されている放熱フィンとを備えており、ヒートパイプが、逆L字状となされかつ長さ方向に伸びる複数の作動流体通路が並列状に設けられたアルミニウム押出形材製逆L字状偏平管と、逆L字状偏平管の垂直部の下端部にアルミニウム製ヘッダを介して接続されかつ長さ方向に伸びる複数の作動流体通路が並列状に設けられたアルミニウム押出形材製水平状偏平管とを備えているものである。
【0006】
この放熱器は、ヒートパイプの相対向する2つの中空板状部のうちのいずれか一方の中空板状部における放熱フィンと接している面とは反対側の面に発熱体が取付けられて用いられる。そして、発熱体の有する熱は、2つの中空板状部を経て放熱フィンに伝わる。したがって、放熱フィンの全ての部分が、十分に放熱の役割を果たし、従来のものに比べて放熱性能が向上する。
【0007】
請求項2の発明による放熱器は、請求項1の発明において、ヒートパイプの相対向する2つの中空板状部のうちのいずれか一方の中空板状部における放熱フィンと接している面とは反対側の面に発熱体が取付けられるようになされているものである。この場合、発熱体の有する熱は、ヒートパイプ内に封入された作動流体の相変化により他方の中空板状部に伝えられ、この中空板状部から放熱フィンに伝えられるとともに、発熱体の取付けられている中空板状部の周壁を介して放熱フィンに伝えられる。
【0008】
請求項3の発明による放熱器は、請求項2の発明において、ヒートパイプの発熱体が取り付けられる部分に複数の作動流体通路が形成されており、隣り合う作動流体通路の間の部分に発熱体がねじ止めされるようになされているものである。
請求項4の発明による放熱器は、請求項1〜3のうちのいずれかの発明において、水平状偏平管における隣接する作動流体通路どうしを仕切る全ての仕切壁のうちの1または複数の仕切壁が他の仕切壁よりも厚肉とされ、この厚肉仕切壁を利用して発熱体が取付けられるようになされているものである。
【0009】
【発明の実施の形態】
以下、この発明の実施形態を、図面を参照して説明する。
なお、以下の説明において、「アルミニウム」という語には、純アルミニウムの他にアルミニウム合金を含むものとする。また、以下の説明において、図1の上下、左右をそれぞれ上下、左右といい、これらの図の紙面表側を前、これと反対側を後というものとする。
図1および図2において、放熱器(40)は、正面から見て左方に開口したコ字状のヒートパイプ(41)を備えている。ヒートパイプ(41)は、正面から見て逆L字状となされ、かつ長さ方向に伸びる複数の作動流体通路(43)が並列状に設けられているアルミニウム押出形材製偏平管(42)と、逆L字状偏平管(42)の右垂直部(42a)の下端部にアルミニウム製ヘッダ(44)を介して接続され、かつ長さ方向に伸びる複数の作動流体通路(46)が並列状に設けられているアルミニウム押出形材製水平状偏平管(45)とを備えている。
【0010】
逆L字状偏平管(42)の上水平部(42b)の左端部は、全ての通路(43)が連通するようにアルミニウム製ヘッダ(6)に接続されている。水平状偏平管(45)の左端開口はアルミニウム製閉鎖部材(47)により閉鎖されている。また、水平状偏平管(45)における隣接する作動流体通路(46)どうしを仕切る全ての仕切壁(48)(48A)のうち幅方向の中央部の仕切壁(48A)は、他の仕切壁(48)よりも厚肉となっている。そして、両偏平管(42)(45)および両ヘッダ(6)(44)の内部が真空状となされるとともに作動流体が封入されることによりヒートパイプ(41)が形成されている。したがって、ヒートパイプ(41)は、相対向する上下の水平中空板状部(41A)(41B)と、両水平中空板状部(41A)(41B)の右端どうしを相互に連結する右垂直中空板状部(41C)(中空連結部)とを備えていることになり、下水平中空板状部(41B)が蒸発部、上水平中空板状部(41A)が凝縮部とそれぞれなっている。
【0011】
ヒートパイプ(41)の上下の水平中空板状部(41A)(41B)間に放熱フィン(49)が配され、かつ両水平中空板状部(41A)(41B)にそれぞれ接した状態でろう付されている。放熱フィン(49)は、左右方向に並んで配置された複数のフィン部材(50)よりなる。各フィン部材(50)は横断面両歯櫛状のアルミニウム押出形材製で、前後方向と平行になっている垂直板状茎部(50a)と、これの両面に上下方向に間隔をおいて一体に形成された複数の水平板状歯部(50b)とよりなる。そして、フィン部材(50)は、隣り合うものどうしの水平板状歯部(50b)先端どうしが突き合わさるように左右方向に並べられ、アルミニウムブレージングシート(9)を介してヒートパイプ(41)の上下水平中空板状部(41A)(41B)にそれぞれろう付されている。そして、放熱フィン(49)には、図示しないファンにより、前方から後方に向かって冷却風が送られるようになっている。
【0012】
ヒートパイプ(41)の下水平中空板状部(41B)の厚肉仕切壁(48A)と対応する部分に、その下面からねじ穴(11)が形成され、このねじ穴(11)に、発熱体(S)を貫通したねじ(12)がねじ嵌められるようになっており、これにより発熱体(S)が下水平中空板状部(41B)下面に取付けられている。
【0013】
発熱体(S)の熱は、ヒートパイプ(41)の下水平中空板状部(41B)の周壁および仕切壁(48)(48A)を介して放熱フィン(49)に伝わり、フィン(49)から放熱される。また、これと同時に、発熱体(S)の熱は、作動流体の相変化により上水平中空板状部(41A)に伝えられ、ここから放熱フィン(49)に伝えられ、フィン(49)から放熱される。
【0014】
上記において、偏平管(45)の全ての仕切壁(48)(48A)のうち幅方向の中央部のものが厚肉仕切壁(48A)とされ、この厚肉仕切壁(48A)を利用して発熱体(S)が取付けられるようになっているが、他の1つの仕切壁を厚肉としたり、あるいは複数の仕切壁を厚肉とし、これらの厚肉仕切壁を利用して発熱体(S)を取付けてもよい。
なお、上記実施形態において、放熱フィンの形状は、図示したものに限定されるものではなく、適宜変更可能である。
【0015】
【発明の効果】
この発明の放熱器によれば、上述のように、従来の放熱器に比べて放熱効率が向上する。したがって、従来の放熱器に比べて小型化を図ることができる。
【図面の簡単な説明】
【図1】 この発明の実施形態を示す正面図である。
【図2】 同じく一部切欠き分解斜視図である。
【符号の説明】
(40):放熱器
(41):ヒートパイプ
(41A)(41B):中空板状部
(41C):中空板状部(中空連結部)
(42) :逆L字状偏平管
(45) :水平状偏平管
(49) :放熱フィン [0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radiator, and more particularly to a radiator for radiating heat from a semiconductor element such as a transistor or a thyristor.
[0002]
[Prior art]
Conventionally, as this kind of radiator, one having a radiation fin fixed to the upper surface of a metal plate having a heating element mounting portion on one side is known (see Japanese Utility Model Publication No. 62-23091).
[0003]
[Problems to be solved by the invention]
However, in the conventional heat radiator, the heat of the heating element is only transmitted to the heat radiating fin through the metal plate, and the upper portion of the fin does not sufficiently perform the heat radiating role. Therefore, there has been a problem that the heat dissipation performance is not sufficient.
[0004]
An object of the present invention is to provide a radiator that solves the above problems and has improved heat dissipation performance.
[0005]
[Means for Solving the Problems]
The radiator according to the invention of claim 1 is a U-shaped heat pipe having two hollow plate-like portions opposed to each other and a hollow connecting portion for connecting both hollow plate-like portions to each other, and opposite hollows in the heat pipe. A plurality of operations in which the heat pipe is formed in an inverted L shape and extends in the length direction, and is provided between the plate-like portions and is fixed in contact with both hollow plate-like portions. A reverse L-shaped flat tube made of extruded aluminum having fluid passages arranged in parallel, and a plurality of pipes connected to the lower end of the vertical portion of the reverse L-shaped flat tube via an aluminum header and extending in the length direction And a horizontal flat tube made of an aluminum extruded member provided with a plurality of working fluid passages arranged in parallel .
[0006]
This radiator is used with a heating element attached to the surface opposite to the surface in contact with the radiation fin in one of the two hollow plate portions of the heat pipe facing each other. It is done. And, the heat of the outgoing heat body is transmitted to the heat radiating fin through two hollow plate-shaped portion. Therefore, all the portions of the heat radiating fins sufficiently play a role of heat radiating, and the heat radiating performance is improved as compared with the conventional one.
[0007]
The radiator according to the invention of claim 2 is the surface of the heat pipe according to the invention of claim 1, which is in contact with the radiation fin in one of the two hollow plate-like portions of the heat pipe facing each other. A heating element is attached to the opposite surface. In this case, the heat of the heating element is transmitted to the other hollow plate-like part by the phase change of the working fluid sealed in the heat pipe, and is transmitted from the hollow plate-like part to the heat radiating fin, and the heating element is attached. It is transmitted to the heat radiating fins through the peripheral wall of the hollow plate-shaped part.
[0008]
According to a third aspect of the present invention, there is provided a radiator according to the second aspect , wherein a plurality of working fluid passages are formed in a portion of the heat pipe to which the heating element is attached, and the heating element is provided in a portion between adjacent working fluid passages. Is designed to be screwed.
A radiator according to a fourth aspect of the present invention is the heat radiator according to any one of the first to third aspects, wherein one or a plurality of partition walls among all the partition walls partitioning adjacent working fluid passages in the horizontal flat tube. Is made thicker than the other partition walls, and the heating element is attached by using the thick partition walls .
[0009]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings .
In the following description, the term “aluminum” includes aluminum alloys in addition to pure aluminum. In the following description, the upper and lower sides and the left and right sides in FIG. 1 are referred to as the upper and lower sides and the left and right sides, respectively .
1 and 2, the radiator (40) includes a U-shaped heat pipe (41) opened leftward as viewed from the front. The heat pipe (41) is formed in an inverted L shape when viewed from the front, and a flat tube (42) made of an aluminum extruded shape member provided with a plurality of working fluid passages (43) extending in the length direction in parallel. And a plurality of working fluid passages (46) connected in parallel to the lower end of the right vertical portion (42a) of the inverted L-shaped flat tube (42) via the aluminum header (44) and extending in the length direction. And a horizontal flat tube (45) made of an aluminum extruded profile.
[0010]
The left end portion of the upper horizontal portion (42b) of the inverted L-shaped flat tube (42) is connected to the aluminum header (6) so that all the passages (43) communicate with each other. The left end opening of the horizontal flat tube (45) is closed by an aluminum closing member (47). Further, among all the partition walls (48) (48A) that partition adjacent working fluid passages (46) in the horizontal flat pipe (45), the central partition wall (48A) in the width direction is the other partition wall. It is thicker than (48). Then, the insides of both the flat tubes (42) and (45) and the headers (6) and (44) are evacuated and the working fluid is sealed to form a heat pipe (41). Therefore, the heat pipe (41) is a right vertical hollow that mutually connects the upper and lower horizontal hollow plate portions (41A) (41B) facing each other and the right ends of both horizontal hollow plate portions (41A) (41B). A plate-like portion (41C) (hollow connecting portion), the lower horizontal hollow plate-like portion (41B) is an evaporation portion, and the upper horizontal hollow plate-like portion (41A) is a condensation portion. .
[0011]
The heat radiation fins (49) are arranged between the upper and lower horizontal hollow plate portions (41A) (41B) of the heat pipe (41) and are in contact with both horizontal hollow plate portions (41A) (41B). It is attached. The heat radiating fin (49) includes a plurality of fin members (50) arranged side by side in the left-right direction. Each fin member (50) is made of an extruded aluminum material having a cross-sectional double-toothed comb shape, and a vertical plate-like stem portion (50a) parallel to the front-rear direction and a vertical interval on both sides thereof. It consists of a plurality of horizontal plate teeth (50b) formed integrally. The fin members (50) are arranged in the left-right direction so that the ends of the horizontal plate-like teeth (50b) of adjacent ones are in contact with each other, and the heat pipe (41) The upper and lower horizontal hollow plate portions (41A) and (41B) are brazed. The cooling fins (49) are fed with cooling air from the front to the rear by a fan (not shown).
[0012]
A screw hole (11) is formed from the lower surface of the lower horizontal hollow plate-like portion (41B) of the heat pipe (41) corresponding to the thick partition wall (48A), and heat is generated in the screw hole (11). A screw (12) penetrating the body (S) is screwed, and thereby the heating element (S) is attached to the lower surface of the lower horizontal hollow plate portion (41B).
[0013]
The heat of the heating element (S) is transferred to the radiating fin (49) through the peripheral wall and partition walls (48) (48A) of the lower horizontal hollow plate-like portion (41B) of the heat pipe (41), and the fin (49) Radiated from the heat. At the same time, the heat of the heating element (S) is transmitted to the upper horizontal hollow plate (41A) by the phase change of the working fluid, and from here to the radiating fin (49), from the fin (49). Heat is dissipated.
[0014]
In the above, the central part in the width direction of all the partition walls (48) (48A) of the flat tube (45) is the thick partition wall (48A), and this thick partition wall (48A) is used. The heating element (S) can be attached, but the other one partition wall is made thick, or a plurality of partition walls are made thick, and these thick partition walls are used to make the heating element (S) may be attached .
In the above embodiment, the shape of the radiating fin is not limited to the illustrated shape, and can be changed as appropriate.
[0015]
【The invention's effect】
According to the heat radiator of the present invention, as described above, the heat radiation efficiency is improved as compared with the conventional heat radiator. Therefore, the size can be reduced as compared with the conventional radiator.
[Brief description of the drawings]
1 is a front view showing a preferred form status of the present invention.
FIG. 2 is an exploded perspective view partially cut away.
[Explanation of symbols]
(40) : Radiator
(41) : Heat pipe
(41A) (41B) : Hollow plate
(41C) : Hollow plate-like part (hollow connection part)
(42) : Inverted L-shaped flat tube
(45) : Horizontal flat tube
(49) : Radiating fin
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29094895A JP3697560B2 (en) | 1995-11-09 | 1995-11-09 | Radiator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP29094895A JP3697560B2 (en) | 1995-11-09 | 1995-11-09 | Radiator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH09133482A JPH09133482A (en) | 1997-05-20 |
| JP3697560B2 true JP3697560B2 (en) | 2005-09-21 |
Family
ID=17762563
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP29094895A Expired - Fee Related JP3697560B2 (en) | 1995-11-09 | 1995-11-09 | Radiator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3697560B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008298409A (en) * | 2007-06-04 | 2008-12-11 | Furukawa Electric Co Ltd:The | Pressure welding heat pipe |
| JP2017534826A (en) * | 2014-09-15 | 2017-11-24 | アアヴィッド・サーマロイ・エルエルシー | Thermosiphon with a bent tube |
| US10211125B2 (en) | 2017-07-19 | 2019-02-19 | Heatscape.Com, Inc. | Configurable mounting hole structure for flush mount integration with vapor chamber forming plates |
| TWI830611B (en) * | 2023-03-01 | 2024-01-21 | 薩摩亞商塔普林克科技有限公司 | Integrated heat dissipation module structure |
-
1995
- 1995-11-09 JP JP29094895A patent/JP3697560B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH09133482A (en) | 1997-05-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3525498B2 (en) | Boiling cooling device | |
| JP2009198173A (en) | Heat sink with heat pipes and method for manufacturing the same | |
| KR20040012593A (en) | Heat pipe unit and heat pipe type heat exchanger | |
| CN215345580U (en) | cooling equipment | |
| JP2024166006A (en) | Dual-liquid pump liquid cooling and heat dissipation device | |
| CN217428571U (en) | Radiator and power module | |
| JP3697560B2 (en) | Radiator | |
| JPH087249Y2 (en) | Heat exchanger | |
| JP2005537666A (en) | Heat sink with folding fin heat exchanger core | |
| JP2003188327A (en) | Heat dissipation module | |
| US20060090883A1 (en) | Liquid-cooled heat radiator kit | |
| JPH0561556B2 (en) | ||
| JP3630201B2 (en) | Integrated heat exchanger | |
| JP4892403B2 (en) | Heat pipe type heat dissipation device | |
| JPH0341478Y2 (en) | ||
| CN213543313U (en) | Heat sink device | |
| JPH0333070Y2 (en) | ||
| CN114430647A (en) | Relief tooth phase change radiator | |
| JP3810119B2 (en) | Boiling cooler | |
| JPH05304383A (en) | Heat sink for high output electronic apparatus | |
| CN2739795Y (en) | Improved structure of radiator for liquid-cooled radiator | |
| JPH0217142Y2 (en) | ||
| CN217636927U (en) | Heat pipe close-packed radiator | |
| JPH0412691Y2 (en) | ||
| JP3421883B2 (en) | Radiator |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20050203 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20050215 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20050415 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20050524 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20050620 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| LAPS | Cancellation because of no payment of annual fees |