CN103521669A - Engine connecting rod powder forging method - Google Patents
Engine connecting rod powder forging method Download PDFInfo
- Publication number
- CN103521669A CN103521669A CN201310481757.2A CN201310481757A CN103521669A CN 103521669 A CN103521669 A CN 103521669A CN 201310481757 A CN201310481757 A CN 201310481757A CN 103521669 A CN103521669 A CN 103521669A
- Authority
- CN
- China
- Prior art keywords
- forging
- prefabricated blank
- similar figures
- die
- engine link
- 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.)
- Granted
Links
Images
Landscapes
- Forging (AREA)
- Shafts, Cranks, Connecting Bars, And Related Bearings (AREA)
Abstract
The invention provides an engine connecting rod powder forging method which includes the first step of manufacturing preformed blank of similar powder and the second step of forging the preformed blank. According to the engine connecting rod powder forging method, metal powder is adopted to serve as raw materials, the preformed blank is manufactured reasonably, the forging precision of an engine connecting rod is improved, the utilization rate of the raw materials is improved, and energy consumption generated in forging is reduced.
Description
Technical field
The present invention relates to the making field of engine link, be specifically related to a kind of method of engine link power forging.
Background technology
Connecting rod is in automobile engine, to be subject to the great part of alternate stress, require high strength, high accuracy, Fig. 1 is a typical rod forging drawing, orthodox car generally all forges and forms with high strength steel with connecting rod, first the raw material cutting is heated to forging temperature through Medium Frequency Induction Heating Furnace, pressing on forging roll multiple tracks to be rolled into two, be spherical again, stage casing is the blank of round bar shape, blocking on forging press again, finally in finisher, finish-forging is shaped, Fig. 2 is the forging schematic diagram of typical forging connecting rod, as shown in Figure 2, owing to being in upper and lower two open type modules: finish forging in patrix 2.1 and counterdie 2.3, now excess metal overflows and forms overlap 2.7 along by-level die face periphery, and the middle gross weight 2.6 that leaves of macropore, aperture often can not be forged out and is formed blind hole 2.4.Overlap 2.7 treat with gross weight 2.6 after excision, blind hole 2.4 is by machined excision, the metal material of therefore wasting is greater than gross weight 50%, and forging 2.2 peripheries all leave draft angle 2.5 and increased forge weight.
Summary of the invention
In view of this, the invention provides a kind of method of engine link power forging, by adopting metal dust as raw material, and rationally make prefabricated blank, the forging precision that has improved engine link has improved raw-material utilization rate simultaneously, and has reduced the energy consumption producing while forging.
The power forging method of a kind of engine link provided by the invention, comprising:
Step 1: make similar figures powder prefabricated blank;
Step 2: forge described prefabricated blank.
Described step 1 comprises:
Step 1.1: style and the size of determining similar figures prefabricated blank;
Step 1.2: according to style and the size of the definite similar figures prefabricated blank of step 1.1, determine and make similar figures prefabricated blank mould;
Step 1.3: to the in-built powder of similar figures prefabricated blank mould;
Step 1.4: compacting and the demoulding, obtain similar figures powder prefabricated blank.
Described step 1.1 comprises:
Step 1.1.1: the geometry of engine link to be produced is resolved into a plurality of solids;
Step 1.1.2: determine similar figures prefabricated blank based on described a plurality of solids: the centre-to-centre spacing at the two ends of similar figures prefabricated blank is identical with the centre-to-centre spacing at engine link two ends to be produced; The height of described similar figures prefabricated blank is higher than the height of engine link to be produced; The physical dimension of described similar figures prefabricated blank is less than the physical dimension of engine link to be produced; The inner dimensions of described similar figures prefabricated blank is greater than the inner dimensions of engine link to be produced.
Described step 1.2 comprises:
Step 1.2.1: the concave die cavity size of determining similar figures prefabricated blank mould: the floor projection of the similar figures prefabricated blank that described concave die cavity size and step 1.1 are definite is measure-alike;
Step 1.2.2: the horizontal cross-section size of determining similar figures prefabricated blank mould each several part stamping: the floor projection of the similar figures prefabricated blank that the horizontal cross-section size of described each several part stamping and step 1.1 are definite is measure-alike;
Step 1.2.3: according to the pine dress ratio of the density of prefabricated blank and raw meal or according to setting density, determine the dress powder height of similar figures prefabricated blank mould;
Step 1.2.4: make similar figures prefabricated blank mould.
Described step 2 comprises:
Step 2.1: determine forging style and size;
Step 2.2: according to style and the size of the definite forging of step 2.1, determine and make closed forging die;
Step 2.3: heating preforms is also put into closed forging die internal mold, the patrix of closed forging die presses down prefabricated blank forging and stamping also fine and close to the die cavity that is full of closed forging die, then returns patrix;
Step 2.4: eject the counterdie of closed forging die in the die of closed forging die, thereby complete forging molding.
The two ends centre bore of the forging that described step 2.1 is definite is identical apart from the centre-to-centre spacing at the engine link two ends with to be produced; The height of described forging is identical with the height of engine link to be produced; The outer peripheral wall of described forging is partly straight wall; The inner hole wall band at described forging two ends is gradient.
Described step 2.2 comprises:
Step 2.2.1: the die inner cavity size of determining closed forging die: the profile projection size of the forging that the die inner cavity size of described closed forging die is definite with step 2.1 is identical, and the chamber wall of die inner chamber is straight wall;
Step 2.2.2: the large plug and little plug of determining closed forging die: the macropore internal diameter of the forging that the external diameter of described large plug is definite with step 2.1 is identical; The hole diameter of the forging that the external diameter of described little plug is definite with step 2.1 is identical; Short transverse is all with suitable draw taper.
As shown from the above technical solution, the method of a kind of engine link power forging provided by the invention, by adopting similar figures to design to prefabricated blank mould, after being shaped, prefabricated blank compares two centre bore with traditional forging apart from constant, each several part short transverse height increases, and the reduction of peripheral part physical dimension, inner dimensions increases, and guarantees that the prefabricated blank after being shaped can enter forging and molding in closed forging die smoothly; In addition, during prefabricated blank design, substantially follow the principle that unit length equates with forging corresponding site quality, and according to the density of designed prefabricated blank, carry out the design of corresponding size, each position even density in the time of can guaranteeing preform forging.Prefabricated blank is designed to and forging similar shape, and centre bore is apart from identical with forging, and only periphery has uniform gap, guarantees accurate positioning after mould, and unlikely generation such as folds, is not fully filled at the defect.Closed die forging has guaranteed that forging does not go out overlap, without punching recess or blind hole, not only saves a large amount of metals but also die life and greatly improves.
Accompanying drawing explanation
Fig. 1 is typical rod forging drawing;
Fig. 2 is the forging schematic diagram of typical forging connecting rod;
Fig. 3 a is the geometry decomposing schematic representation of engine link to be produced;
Fig. 3 b is the geometry decomposition plan view of engine link to be produced;
Fig. 4 is for adopting the schematic diagram of the definite mould longitudinal middle axis central cross-section place dress powder height of the inventive method;
Fig. 5 a is for adopting the structural representation of the similar figures powder prefabricated blank of the inventive method making;
Fig. 5 b is for adopting the structure top view of the similar figures powder prefabricated blank of the inventive method making;
Fig. 6 is for adopting the definite forging structural representation of the inventive method;
Fig. 7 is for adopting the structural representation of the closed forging die of the inventive method making.
The specific embodiment
For making object, technical scheme and the advantage of the embodiment of the present invention clearer, below the technical scheme in the embodiment of the present invention is conducted further description, obviously, described embodiment is the present invention's part embodiment, rather than whole embodiment.Embodiment based in the present invention, the every other embodiment that those of ordinary skills obtain under the prerequisite of not making creative work, belongs to the scope of protection of the invention.
The method of a kind of engine link power forging provided by the invention, comprising:
Step 1: make similar figures powder prefabricated blank;
Wherein, described step 1 comprises:
Step 1.1: style and the size of determining similar figures prefabricated blank;
Wherein, described step 1.1 comprises:
Step 1.1.1: the geometry of engine link to be produced is resolved into a plurality of solids;
For guaranteeing the shaping of powder prefabricated blank, first the geometry of engine link to be produced is decomposed into powder and is easy to a plurality of solids that are shaped.Fig. 3 a, Fig. 3 b have provided the geometry decomposing schematic representation of engine link to be produced, as shown in Figure 3 a, 3 b, can be divided into along its length five substantially contour solid combinations: large end is strengthened platform 3.1; Large end torus 3.2; Large small end connecting platform extension bar portion 3.3; Bar portion concave part 3.4; The transition portion connecting between each solid of small end torus 3.5. puts aside, when to be forged, is shaped.
Step 1.1.2: determine similar figures prefabricated blank based on described a plurality of solids: the centre-to-centre spacing at the two ends of similar figures prefabricated blank is identical with the centre-to-centre spacing at engine link two ends to be produced; The height of described similar figures prefabricated blank is higher than the height of engine link to be produced; The physical dimension of described similar figures prefabricated blank is less than the physical dimension of engine link to be produced; The inner dimensions of described similar figures prefabricated blank is greater than the inner dimensions of engine link to be produced.
Step 1.2: according to style and the size of the definite similar figures prefabricated blank of step 1.1, determine and make similar figures prefabricated blank mould;
Wherein, described step 1.2 comprises:
Step 1.2.1: the concave die cavity size of determining similar figures prefabricated blank mould: the floor projection of the similar figures prefabricated blank that described concave die cavity size and step 1.1 are definite is measure-alike;
Step 1.2.2: the horizontal cross-section size of determining similar figures prefabricated blank mould each several part stamping: the floor projection of the similar figures prefabricated blank that the horizontal cross-section size of described each several part stamping and step 1.1 are definite is measure-alike.In die, the floor projection size of each upper and lower stamping (5-1,5-2,5-3,5-4,5-5) of motion can be amounted to into the final floor projection profile of prefabricated blank as shown in Figure 5 a;
Step 1.2.3: according to the pine dress ratio of the density of prefabricated blank and raw meal or according to setting density, determine the dress powder height of similar figures prefabricated blank mould;
Fig. 4 is the schematic diagram of mould longitudinal middle axis central cross-section place dress powder height, 4.1～4.5 each hypomere stampings that are respectively corresponding diagram 5a, Fig. 5 b prefabricated blank in figure.
Step 1.2.4: make similar figures prefabricated blank mould.
Step 1.3: to the in-built powder of similar figures prefabricated blank mould;
Step 1.4: compacting and the demoulding, obtain similar figures powder prefabricated blank.
For making to fill compacting and the demoulding smoothly after powder, after pressing down, upper punch forces bed die floating and forces bottom punch to move to machine stop position to be pressed into desired powder prefabricated blank.After last upper punch rising return, the parallel upper top of all bottom punches pushes up pressed compact to plane on die, can take off workpiece and complete pressing process overall process.
Fig. 5 a, Fig. 5 b are for adopting the structural representation of the similar figures powder prefabricated blank of the inventive method making; As shown in Fig. 5 a, Fig. 5 b, similar figures powder prefabricated blank comprises: large end is strengthened platform 5.1; Large end torus 5.2; Large small end connecting platform extension bar portion 5.3; Bar portion concave part 5.4; Small end torus 5.5.The transition portion connecting between each solid puts aside, when to be forged, is shaped.All similar to forging solid except part transition arc, while forging with assurance, each several part is mainly full of die cavity and improves density in the thick mode of Upsetting, and flow seldom along axis direction, metal forming is full, evenly mobile like this, be not prone to folding, the defect such as be not fully filled, farthest guarantee that each position even density, performance are consistent simultaneously.During design, substantially follow the principle that unit length equates with forging quality, and according to the density of designed prefabricated blank, carry out the design of corresponding size.
Step 2: forge described prefabricated blank.
Wherein, described step 2 comprises:
Step 2.1: determine forging style and size;
Wherein, the two ends centre bore of the definite forging of described step 2.1 is identical apart from the centre-to-centre spacing at the engine link two ends with to be produced; The height of described forging is identical with the height of engine link to be produced; The outer peripheral wall of described forging is partly straight wall; The inner hole wall band at described forging two ends is gradient.Fig. 6 is for adopting the definite forging structural representation of the inventive method.
Step 2.2: according to style and the size of the definite forging of step 2.1, determine and make closed forging die;
Wherein, described step 2.2 comprises:
Step 2.2.1: the die inner cavity size of determining closed forging die: the profile projection size of the forging that the die inner cavity size of described closed forging die is definite with step 2.1 is identical, and the chamber wall of die inner chamber is straight wall;
Step 2.2.2: the large plug and little plug of determining closed forging die: the macropore internal diameter of the forging that the external diameter of described large plug is definite with step 2.1 is identical; The hole diameter of the forging that the external diameter of described little plug is definite with step 2.1 is identical; Short transverse is all with suitable draw taper.
Fig. 7 is for adopting the structural representation of the closed forging die of the inventive method making.As shown in Figure 7, closed forging die comprises: patrix sleeve 7.1; Large plug 7.2; Seaming chuck 7.3; Little plug 7.4; Upper small sleeve 7.5;
Integral concave mould 7.6; Counterdie sleeve 7.7; Push-down head 7.8.
Step 2.3: heating preforms is also put into closed forging die internal mold 7.6, the patrix of closed forging die presses down prefabricated blank forging and stamping also fine and close to the die cavity that is full of closed forging die, then returns patrix;
Step 2.4: from ejecting the counterdie of closed forging die in the die 7.6 of closed forging die, counterdie part comprises counterdie sleeve 7.7, push-down head 7.8 and forging, thus complete forging molding.
As shown from the above technical solution, the method of a kind of engine link power forging provided by the invention, by adopting similar figures to design to prefabricated blank mould, after being shaped, prefabricated blank compares two centre bore with traditional forging apart from constant, each several part short transverse height increases, and the reduction of peripheral part physical dimension, inner dimensions increases, and guarantees that the prefabricated blank after being shaped can enter forging and molding in closed forging die smoothly; In addition, during prefabricated blank design, substantially follow the principle that unit length equates with forging corresponding site quality, and according to the density of designed prefabricated blank, carry out the design of corresponding size, each position even density in the time of can guaranteeing preform forging.Prefabricated blank is designed to and forging similar shape, and centre bore is apart from identical with forging, and only periphery has uniform gap, guarantees accurate positioning after mould, and unlikely generation such as folds, is not fully filled at the defect.Closed die forging has guaranteed that forging does not go out overlap, without punching recess or blind hole, not only saves a large amount of metals but also die life and greatly improves.
Finally it should be noted that: above embodiment only, in order to technical scheme of the present invention to be described, is not intended to limit; Although the present invention is had been described in detail with reference to previous embodiment, those of ordinary skill in the art is to be understood that: its technical scheme that still can record aforementioned each embodiment is modified, or part technical characterictic is wherein equal to replacement, and these modifications or replacement do not make the essence of appropriate technical solution depart from the spirit and scope of various embodiments of the present invention technical scheme.
Claims (7)
1. a method for engine link power forging, is characterized in that, described method comprises:
Step 1: make similar figures powder prefabricated blank;
Step 2: forge described prefabricated blank.
2. the method for engine link power forging according to claim 1, is characterized in that, described step 1 comprises:
Step 1.1: style and the size of determining similar figures prefabricated blank;
Step 1.2: according to style and the size of the definite similar figures prefabricated blank of step 1.1, determine and make similar figures prefabricated blank mould;
Step 1.3: to the in-built powder of similar figures prefabricated blank mould;
Step 1.4: compacting and the demoulding, obtain similar figures powder prefabricated blank.
3. the forging method of engine link according to claim 2, is characterized in that, described step 1.1 comprises:
Step 1.1.1: the geometry of engine link to be produced is resolved into a plurality of solids;
Step 1.1.2: determine similar figures prefabricated blank based on described a plurality of solids: the centre-to-centre spacing at the two ends of similar figures prefabricated blank is identical with the centre-to-centre spacing at engine link two ends to be produced; The height of described similar figures prefabricated blank is higher than the height of engine link to be produced; The physical dimension of described similar figures prefabricated blank is less than the physical dimension of engine link to be produced; The inner dimensions of described similar figures prefabricated blank is greater than the inner dimensions of engine link to be produced.
4. according to the method for the engine link power forging described in claim 2 or 3, it is characterized in that, described step 1.2 comprises:
Step 1.2.1: the concave die cavity size of determining similar figures prefabricated blank mould: the floor projection of the similar figures prefabricated blank that described concave die cavity size and step 1.1 are definite is measure-alike;
Step 1.2.2: the horizontal cross-section size of determining similar figures prefabricated blank mould each several part stamping: the floor projection of the similar figures prefabricated blank that the horizontal cross-section size of described each several part stamping and step 1.1 are definite is measure-alike;
Step 1.2.3: according to the pine dress ratio of the density of prefabricated blank and raw meal or according to setting density, determine the dress powder height of similar figures prefabricated blank mould;
Step 1.2.4: make similar figures prefabricated blank mould.
5. the power forging method of engine link according to claim 1, is characterized in that, described step 2 comprises:
Step 2.1: determine forging style and size;
Step 2.2: according to style and the size of the definite forging of step 2.1, determine and make closed forging die;
Step 2.3: heating preforms and put into closed forging die, the patrix of closed forging die presses down prefabricated blank forging and stamping to being full of the die cavity of closed forging die fine and close, then returns patrix;
Step 2.4: eject with push-down head the powder forging being forged in the die of closed forging die, thereby complete forging molding.
6. the power forging method of engine link according to claim 5, is characterized in that, the two ends centre bore of the forging that described step 2.1 is definite is identical apart from the centre-to-centre spacing at the engine link two ends with to be produced; The height of described forging is identical with the height of engine link to be produced; The outer peripheral wall of described forging is partly straight wall; The inner hole wall band at described forging two ends is gradient.
7. according to the power forging method of the engine link described in claim 5 or 6, it is characterized in that, described step 2.2 comprises:
Step 2.2.1: the die inner cavity size of determining closed forging die: the profile projection size of the forging that the die inner cavity size of described closed forging die is definite with step 2.1 is identical, and the chamber wall of die inner chamber is straight wall;
Step 2.2.2: the large plug and little plug of determining closed forging die: the macropore internal diameter of the forging that the external diameter of described large plug is definite with step 2.1 is identical; The hole diameter of the forging that the external diameter of described little plug is definite with step 2.1 is identical; Short transverse is all with suitable draw taper.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310481757.2A CN103521669B (en) | 2013-10-15 | 2013-10-15 | The method of engine link power forging |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201310481757.2A CN103521669B (en) | 2013-10-15 | 2013-10-15 | The method of engine link power forging |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103521669A true CN103521669A (en) | 2014-01-22 |
| CN103521669B CN103521669B (en) | 2016-08-24 |
Family
ID=49924224
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201310481757.2A Expired - Fee Related CN103521669B (en) | 2013-10-15 | 2013-10-15 | The method of engine link power forging |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103521669B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104128549A (en) * | 2014-07-18 | 2014-11-05 | 玉溪大红山矿业有限公司 | Die for powder forging of automobile connecting rod |
| CN104128607A (en) * | 2014-07-21 | 2014-11-05 | 玉溪大红山矿业有限公司 | Manufacturing technology of vehicle connecting rod |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009088771A2 (en) * | 2008-01-04 | 2009-07-16 | Gkn Sinter Metals, Llc | Prealloyed copper powder forged connecting rod |
-
2013
- 2013-10-15 CN CN201310481757.2A patent/CN103521669B/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009088771A2 (en) * | 2008-01-04 | 2009-07-16 | Gkn Sinter Metals, Llc | Prealloyed copper powder forged connecting rod |
Non-Patent Citations (5)
| Title |
|---|
| 中国机械工程学会等: "《中国模具设计大典：第4卷，锻模与粉末冶金模设计》", 31 January 2003, 江西科学技术出版社, article "粉末锻造模具设计", pages: 1161 * |
| 周昌林: "粉末锻造连杆断裂技术的特点", 《汽车工艺与材料》, no. 11, 30 November 1996 (1996-11-30), pages 44 * |
| 周昌林: "粉末锻造连杆裂断技术的特点", 《汽车工艺与材料》, no. 11, 30 November 1996 (1996-11-30), pages 44 * |
| 模具设计与制造技术教育丛书编委会: "《模具结构设计》", 31 October 2003, 机械工业出版社, article "粉末冶金模具结构设计", pages: 244 * |
| 魏汝梅: "《锻造工》", 30 September 2004, 化学工业出版社，工业装备与信息工程出版中心, article "压制成形", pages: 347 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104128549A (en) * | 2014-07-18 | 2014-11-05 | 玉溪大红山矿业有限公司 | Die for powder forging of automobile connecting rod |
| CN104128607A (en) * | 2014-07-21 | 2014-11-05 | 玉溪大红山矿业有限公司 | Manufacturing technology of vehicle connecting rod |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103521669B (en) | 2016-08-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103567248B (en) | A kind of inside and outside compromise face band muscle cylinder extrusion molding dies | |
| CN102672096A (en) | Precision die forging and shaping technical method for automobile steering knuckle rough type parts | |
| CN103357804A (en) | Damping type flow control forming process and die for aluminium-alloy rib-plate forging | |
| CN103121075B (en) | Hot forging method for transmission shaft yoke with horizontal yoke part | |
| CN103567340A (en) | Novel precision forging technology of straight toothed spur gear for automobile and mold | |
| CN102814447A (en) | High-speed train brake disc hub forging die and design method thereof | |
| CN203265502U (en) | Hot forging device for transmission shaft joint fork with horizontal fork part | |
| CN209614103U (en) | The blank mold structure of automobile engine using new energy resources gear shaft enclosed forging and forming | |
| CN104550624B (en) | The near-net-shape forging method of nuclear reactor pressure container integration bottom (head) | |
| CN100411770C (en) | Generator magnetic pole precision forging method | |
| CN109590426A (en) | The blank mold structure of automobile engine using new energy resources gear shaft enclosed forging and forming | |
| CN103521669A (en) | Engine connecting rod powder forging method | |
| CN205614005U (en) | Duplex position forward finishing mould | |
| CN102717014B (en) | Method for freely forging casing elevator for petroleum drilling and production | |
| CN103658500A (en) | Precise warm forging one-time forming new technology of straight tooth cylinder inner gear | |
| CN106862449B (en) | The closed die forging forging method of complete-section tunnel boring machine hobboing cutter cutter ring | |
| CN103521668A (en) | Method for extrusion forming of high-strength complex aluminum alloy special-shaped outer hexagon seat metal plate | |
| CN105921662A (en) | Dual-station forward finishing die and finishing process | |
| CN202343841U (en) | Precision forging and forming die for blank of differential case | |
| CN102784808B (en) | A kind of asymmetric high muscle complex section workpiece Accurate Shaping mould | |
| CN204657385U (en) | The combination die of automobile axle clutch plate gear blank warm and hot forging | |
| CN201644691U (en) | Composite forming die mold of complicated axial forging with shaft shoulder and flange plate | |
| CN212495122U (en) | Pre-forging die | |
| CN111014553B (en) | Forging method for controlling size angle of irregular triangular rough shape | |
| CN103753157A (en) | Process method and rolling machine for gear blank forming |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20160824 Termination date: 20211015 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |