CN110640058A - Gear rolling forming process - Google Patents
Gear rolling forming process Download PDFInfo
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- CN110640058A CN110640058A CN201810681278.8A CN201810681278A CN110640058A CN 110640058 A CN110640058 A CN 110640058A CN 201810681278 A CN201810681278 A CN 201810681278A CN 110640058 A CN110640058 A CN 110640058A
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- workpiece
- tooth plate
- tooth
- twisting
- rolling
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21H—MAKING PARTICULAR METAL OBJECTS BY ROLLING, e.g. SCREWS, WHEELS, RINGS, BARRELS, BALLS
- B21H3/00—Making helical bodies or bodies having parts of helical shape
- B21H3/02—Making helical bodies or bodies having parts of helical shape external screw-threads ; Making dies for thread rolling
- B21H3/06—Making by means of profiled members other than rolls, e.g. reciprocating flat dies or jaws, moved longitudinally or curvilinearly with respect to each other
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Forging (AREA)
Abstract
The invention provides a gear rolling forming process, which comprises the following steps: the wire raw material is subjected to material shearing and preforming in a cold forging machine and then is formed into a smooth nail blank; and B: the smooth nail blank is formed by twisting a groove in the middle section of the rod part in a gear twisting die, chamfering the top end of the rod part and finally twisting six teeth; the workpiece is arranged in a groove-twisting tooth plate, a groove is formed in the middle section of a rod-twisting part, the workpiece is arranged in a chamfer-twisting tooth plate, the chamfer angle is formed at the top end of the rod-twisting part, the workpiece is extruded to form 6 teeth in a tooth-twisting tooth plate, the tooth-twisting tooth plate comprises a third movable tooth plate and a third fixed tooth plate, and the appearance of each straight tooth of the 6 teeth is smooth by adjusting the angle between the third movable tooth plate and the third fixed tooth plate. The invention provides a gear rolling forming process, which does not need to remove materials and does not damage the forming die structure of a metal fiber structure, thereby achieving the purpose of improving the appearance and the mechanical property of a product; the product quality is more stable, and the material and manual processing cost are saved, so that the product productivity is improved and the product use performance is improved.
Description
Technical Field
The invention belongs to the field of die manufacturing, and particularly relates to a gear rolling forming process.
Background
The workpiece formed by the process is one of accessories of a water closet, and the closed plug shaft is required to have good sealing performance and water passing capacity due to the special use environment and sealing characteristic of the closed plug shaft, but the closed plug shaft produced and sold in the industry and the market at present is integrally formed by turning. Because the turning process removes partial redundant materials on the surface of the product to achieve the purpose of the product size structure, the surface of the turning part is relatively rough, the fibrous tissue of the metal is inevitably damaged in the processing process, the appearance and the mechanical property of the product are seriously influenced, and in use, bad risks such as breaking, shearing and the like are often generated on the turning part; therefore, in order to improve the performance of the product, a forming die which does not need to remove materials and does not damage the metal fiber structure is developed, so as to achieve the purpose of improving the mechanical property of the product. Meanwhile, the production efficiency can be greatly improved, and the production cost is reduced.
Disclosure of Invention
In view of the above, the invention provides a gear rolling forming process, which does not need to remove materials and damage the forming die structure of the metal fiber structure, so as to improve the appearance and mechanical properties of the product; the product quality is more stable, and the material and manual processing cost are saved, so that the product productivity is improved and the product use performance is improved.
A gear rolling forming process comprises the following steps: step A: cold forging the wire material to form blank of smooth nail; and B: and the smooth nail blank is formed by twisting six teeth in a manner that a groove is arranged in the middle section of the rod twisting part in a gear twisting die, then the top end of the rod twisting part is chamfered.
Preferably, step a specifically includes step a 1: the wire raw material enters a cold forging machine tool through a conveying device, and is cut into workpieces with certain lengths through a shearing device in the cold forging machine tool.
Preferably, step a specifically includes step a 2: the workpiece is conveyed to a die stamping tool through a feeding device for head preforming, the die holder moves upwards after preforming, and the die stamping tool retreats.
Preferably, step a specifically includes step a 3: and (4) the workpiece enters a secondary punching die to be formed into a workpiece of the smooth nail blank.
Preferably, step B specifically includes step B1: the workpiece is placed into a bin of the thread rolling machine, the workpiece slides downwards from a discharging slideway of the bin, a push knife in the thread rolling machine pushes the workpiece into a thread rolling groove tooth plate, a baffle plate blocks an outlet of the discharging slideway, and the workpiece is enabled to finish a groove in the middle section of a thread rolling rod in the thread rolling groove tooth plate through up-down movement of a first movable tooth plate.
Preferably, step B specifically includes step B11: the groove-rolling tooth plate is replaced by a chamfer-rolling tooth plate in the tooth-rolling machine.
Preferably, step B specifically includes step B2: putting the workpiece with the groove in the middle section of the rod part into a stock bin of a thread rolling machine, sliding the workpiece downwards from the stock bin through a discharging slideway, pushing the workpiece into a chamfer rolling tooth plate by a push broach, and blocking an outlet of the discharging slideway by a baffle plate; the second movable tooth plate moves up and down, so that the workpiece is chamfered at the top end of the rod rubbing part in the chamfering tooth plate.
Preferably, step B specifically includes step B21: and replacing the chamfering tooth plate with the gear rolling tooth plate in the gear rolling machine.
Preferably, step B specifically includes step B3: putting the workpiece with the chamfer angle at the top end of the rod part into a stock bin of a thread rolling machine, sliding the workpiece downwards from the stock bin through a discharging slideway, pushing the workpiece into a thread rolling tooth plate by a push broach, and blocking an outlet of the discharging slideway by a baffle plate; and the third movable pressing plate moves up and down, so that the workpiece is extruded and formed into 6 teeth in the gear rolling tooth plate.
Preferably, step B specifically includes step B31: the end of the straight tooth on the surface of the workpiece after 6 teeth are formed is in a chamfered shape, the movable dental plate of the gear rolling dental plate gradually reduces the chamfer angle and height, and the materials on two sides of the straight tooth are extruded to fill the previous chamfer defect, so that the appearance of each straight tooth of 6 teeth is flat.
By adopting the gear rolling forming process, the one-time processing is completed, and the existing turning processing process in the industry is replaced; because the whole forming process does not need to remove materials and does not damage the metal fiber tissue, the formed product has super-strong and super-toughness mechanical properties: for example, stainless steel SUS316 material products have tensile strength of more than or equal to 598kgf/mm2 (standard of more than or equal to 520kgf/mm2) after cold heading forming, and elongation after fracture of more than or equal to 47% (standard of more than or equal to 40%); greatly saving materials and labor processing cost and improving the working efficiency.
Drawings
FIG. 1 is a drawing of a blank workpiece of a formed smooth nail according to the present invention.
FIG. 2 is a drawing of a formed midship groove workpiece according to the present invention.
FIG. 3 is a diagram of a finished tail-end-twisting chamfer workpiece formed according to the present invention.
FIG. 4 is a drawing of a six-tooth twined workpiece formed according to the present invention.
Fig. 5 is a working schematic diagram of the gear rolling process of the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Referring to fig. 1-5, a gear rolling forming process includes the following steps:
step A: cold forging the wire material to form blank of smooth nail;
and B: and the smooth nail blank is formed by twisting six teeth in a manner that a groove is arranged in the middle section of the rod twisting part in a gear twisting die, then the top end of the rod twisting part is chamfered.
More specifically, step a includes a 1: the wire raw material enters a cold forging machine tool through a conveying device, and the wire is cut into a workpiece with a certain length through a shearing device in the cold forging machine tool; the wire rod raw materials are coiled raw materials, and before entering a cold forging machine tool, the wire rod is straightened through a straightening device, and the straightening device comprises a plurality of straightening wheels. The straightened wire raw materials are conveyed to a shearing device, the shearing length is preset, and the shearing device shears the wire raw materials into workpiece raw materials with certain length.
More specifically, step a further comprises a2 and A3: the workpiece is sent to a main die and a stamping die through a feeding device for head pre-forming, the stamping of the stamping die is stable, the forming is about 70%, a die holder moves upwards after pre-forming, and the stamping die moves backwards. And (3) putting the preformed workpiece into a secondary punching die to form a workpiece of the smooth nail blank, wherein the forming rate is about 80%. The cold forging process is about 80 percent of the forming work piece, the forming speed is high, and the efficiency is high. Cold forging is a forming process in which the material is recrystallized at a temperature lower than or equal to the recrystallization temperature, and is forging at a temperature lower than or equal to the recovery temperature. The cold forging materials are mostly aluminum and partial alloys with small deformation resistance and good plasticity at room temperature; the cold forging piece has good surface quality and high dimensional precision, and can replace some cutting processing. The cold forging can strengthen the metal and improve the strength of the parts. In view of the special use environment of the workpiece, the cold forging technology is adopted to carry out primary forming on the workpiece, so that the metal strength of the formed round-head smooth nail is stronger.
Preferably, step B specifically includes B1: the preliminarily processed workpiece is placed into a storage bin in the thread rolling machine, the vibration disc vibrates, the workpiece sequentially enters a discharging slideway from the storage bin and slides down to a feeding channel along the discharging slideway, and a baffle plate blocks an outlet of the discharging slideway and prevents other workpieces from sliding down. The push broach in the thread rolling machine pushes a workpiece into the thread rolling groove dental lamina from the feeding channel, the thread rolling groove dental lamina comprises a first movable dental lamina and a first fixed dental lamina, the workpiece is arranged between the first movable dental lamina and the first fixed dental lamina, the tooth distance is preset between the first movable dental lamina and the first fixed dental lamina, the middle groove of the first movable dental lamina, which moves the forming workpiece up and down, is used for adjusting the forming state through adjusting the gap between the movable dental lamina and the fixed dental lamina. And after the groove in the middle section of the workpiece is formed, replacing the groove-rolling tooth plate with a chamfer-rolling tooth plate in the tooth rolling machine.
Preferably, step B specifically includes B2: the workpiece which is rubbed with the grooves in the middle section of the rod part is placed into a storage bin of the thread rolling machine again, the vibration of the vibration disc enables the workpiece to enter the discharging slideway orderly from the storage bin, the workpiece slides down to the feeding channel from the discharging slideway, and the material baffle blocks a discharge hole of the discharging slideway. The push broach pushes the workpiece into the chamfering tooth plate, the chamfering tooth plate comprises a second movable tooth plate and a second fixed tooth plate, the tooth distance between the second movable tooth plate and the second fixed tooth plate is preset, the second movable tooth plate moves up and down, the workpiece is chamfered at the top end of the molding rod part in the chamfering tooth plate, and then the workpiece is unloaded. And after the top end of the rod part of the workpiece is chamfered and molded, replacing the chamfer-rubbing tooth plate with a tooth-rubbing tooth plate in the tooth-rubbing machine.
Preferably, step B specifically includes B3: putting the workpiece with the chamfer angle at the top end of the rod part into a stock bin of the thread rolling machine again, vibrating the workpiece from the stock bin through a vibrating disc to enable the workpiece to sequentially enter a discharging slideway, sliding the workpiece down to a feeding channel from the discharging slideway, and blocking an outlet of the discharging slideway by a baffle plate; pushing the workpiece into the gear rolling tooth plate by the push broach; the tooth rolling die comprises a third movable die and a third fixed die, a workpiece enters between the third movable die and the third fixed die and moves up and down through the third movable die, and the workpiece is extruded and formed into 6 teeth in the tooth rolling die with preset tooth pitch. The end of the straight tooth on the surface of the workpiece after 6 teeth are formed is in a chamfered shape, the movable dental plate of the gear rolling dental plate gradually reduces the chamfer angle and height, and the materials on two sides of the straight tooth are extruded to fill the previous chamfer defect, so that the appearance of each straight tooth of 6 teeth is flat. The gap between the third movable tooth plate and the third fixed tooth plate is adjustable, and the forming state and the fullness degree of 6 teeth on the workpiece are adjusted by adjusting the gap; the angle formed between the third movable tooth plate and the third fixed tooth plate is adjustable, and the chamfer defect formed on the teeth in the tooth rolling process is adjusted and compensated by adjusting the angle between the third movable tooth plate and the third fixed tooth plate, so that the appearance of each straight tooth of 6 teeth is smooth.
Referring to fig. 5, the thread rolling processing device 100 includes a movable dental plate 10, a movable dental plate mounting seat 11, a fixed dental plate 20, a fixed dental plate mounting seat 21, a workpiece 30, a blanking slideway 40, a striker plate 50 and a push broach 60; the workpieces 30 enter the discharging slideway 40 from the stock bin, the stock bin can be a vibrating disk, in the vibrating feeding process of the vibrating disk, the workpieces 30 are orderly arranged and then enter the discharging slideway 40, the material baffle plate 50 is opened, the workpieces 30 enter the feeding channel from the discharging slideway 40, the material baffle plate 50 is closed, and other workpieces 30 are not allowed to slide downwards; the push broach 60 is used for pushing the workpiece 30 in the feeding channel to a gap between the movable dental plate 10 and the fixed dental plate 20, the movable dental plate 10 is driven by the movable dental plate mounting seat 11 to move up and down, the fixed dental plate 20 is fixed, and the workpiece 30 is extruded and formed into 6 teeth between the movable dental plate 10 and the fixed dental plate 20; the gap between the movable dental plate 10 and the fixed dental plate 20 is adjustable, and the forming state and the plumpness of 6 teeth on the workpiece 30 are adjusted by adjusting the gap between the movable dental plate 10 and the fixed dental plate 20.
Referring to fig. 1-5, in the gear rolling process of the present invention, all the workpieces are finished with the middle rolling groove of the first gear rolling process, and then the groove rolling die is replaced with the chamfer rolling die; then, putting the workpiece with the groove in the middle section in a bin, enabling the workpiece to enter a chamfer angle at the tail part of the chamfer angle dental lamina forming workpiece, enabling all the workpieces to be formed with chamfer angles at the tail part, and then replacing the chamfer angle dental lamina with a gear rolling dental lamina; and then, putting all the workpieces with the chamfered tail parts into a storage bin, and finishing the twisting of the workpieces with 6 teeth in a tooth rolling tooth plate.
Referring to fig. 1-5, in the gear rolling forming process provided by the invention, a novel forming die structure can be completed by one-step processing, and the existing turning process in the industry is replaced; because the whole forming process does not need to remove materials and does not damage the metal fiber tissue, the formed product has super-strong and super-toughness mechanical properties: for example, stainless SUS316 material products have a tensile strength of 598kgf/mm2 (standard 520kgf/mm2) or more after cold heading, and an elongation after fracture of 47% or more (standard 40% or more). The invention is cold-forged and formed initially, thus enhancing the metal strength of the workpiece; the gear rolling forming process greatly saves materials and labor processing cost, and improves working efficiency.
The invention is described in the following description with reference to the accompanying drawings, which are incorporated in and constitute a part of this specification, wherein like reference numerals designate like parts throughout the several views.
Claims (10)
1. The gear rolling forming process is characterized by comprising the following steps of:
step A: cold forging the wire material to form blank of smooth nail;
and B: and the smooth nail blank is formed by twisting six teeth in a manner that a groove is arranged in the middle section of the rod twisting part in a gear twisting die, then the top end of the rod twisting part is chamfered.
2. The gear shaping process according to claim 1, wherein the step a specifically comprises the step a 1: the wire raw material enters a cold forging machine tool through a conveying device, and the wire is cut into workpieces with certain lengths through a shearing device in the cold forging machine tool.
3. The gear shaping process according to claim 1, wherein the step a specifically comprises the step a 2: and the workpiece is conveyed to a die stamping die through a feeding device for performing head preforming, the die holder moves upwards after performing, and the die stamping die retreats.
4. The gear shaping process according to claim 3, wherein the step A specifically comprises the step A3: and the workpiece enters a secondary punching die to be formed into the workpiece of the smooth nail blank.
5. The gear shaping process according to claim 1, wherein the step B specifically comprises the step B1: the workpiece is placed into a bin of the thread rolling machine, the workpiece slides downwards from a discharging slideway of the bin, a push knife in the thread rolling machine pushes the workpiece into a thread rolling groove tooth plate, a baffle plate blocks an outlet of the discharging slideway, and the workpiece is enabled to move up and down through a first moving tooth plate so that the workpiece is arranged in the thread rolling groove tooth plate to complete a groove in the middle section of a thread rolling rod.
6. The gear shaping process according to claim 5, wherein the step B specifically comprises the step B11: and replacing the groove-rolling tooth plate with a chamfer-rolling tooth plate in the tooth rolling machine.
7. The gear shaping process according to claim 6, wherein the step B specifically comprises the step B2: the workpiece with the groove in the middle section of the rod part is placed into a storage bin of a thread rolling machine, the workpiece slides downwards from the storage bin through the blanking slideway, the push knife pushes the workpiece into the chamfer tooth plate, and the striker plate blocks the outlet of the blanking slideway; and the second movable tooth plate moves up and down, so that the workpiece can complete the chamfering of the top end of the rod rubbing part in the chamfering tooth plate.
8. The gear shaping process according to claim 7, wherein the step B specifically comprises the step B21: and replacing the chamfering tooth plate with a tooth rolling tooth plate in the tooth rolling machine.
9. The gear shaping process according to claim 8, wherein the step B specifically comprises the step B3: putting the workpiece with the chamfer angle at the top end of the rod part into a storage bin of a thread rolling machine, enabling the workpiece to slide downwards from the storage bin through the blanking slideway, pushing the workpiece into the thread rolling die by the push broach, and blocking an outlet of the blanking slideway by the baffle plate; and the third movable tooth plate moves up and down, so that the workpiece completes extrusion forming of 6 teeth in the gear rolling tooth plate.
10. The gear shaping process according to claim 9, wherein the step B specifically comprises the step B31: the straight tooth end on the surface of the workpiece after 6 teeth are formed is in a chamfered shape, the movable tooth plate of the gear rolling tooth plate gradually reduces the chamfer angle and height, and materials on two sides of the straight teeth are extruded to fill the previous chamfer defect, so that the appearance of each straight tooth of 6 teeth is flat.
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CN201810681278.8A CN110640058A (en) | 2018-06-27 | 2018-06-27 | Gear rolling forming process |
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CN201810681278.8A CN110640058A (en) | 2018-06-27 | 2018-06-27 | Gear rolling forming process |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN111531093A (en) * | 2020-05-08 | 2020-08-14 | 深圳前沿装备有限公司 | Rubbing and extruding forming equipment for producing elastic core and technological process thereof |
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CN102581575A (en) * | 2012-03-21 | 2012-07-18 | 苏州新凌电炉有限公司 | Fabrication process of hexagonal flange toothed bolt |
CN202490906U (en) * | 2012-02-07 | 2012-10-17 | 深圳市寸金实业有限公司 | Cold twisting mould |
CN105397189A (en) * | 2014-09-16 | 2016-03-16 | 郦忠 | Chamfering and rolling polishing die for hinge pin |
CN106282819A (en) * | 2016-08-16 | 2017-01-04 | 宁波瑞国精机工业有限公司 | A kind of high-strength pin and processing method thereof |
CN106984766A (en) * | 2016-01-21 | 2017-07-28 | 东莞市展赐精密五金制品厂 | The hex nut post processing technology of with groove |
-
2018
- 2018-06-27 CN CN201810681278.8A patent/CN110640058A/en active Pending
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN202490906U (en) * | 2012-02-07 | 2012-10-17 | 深圳市寸金实业有限公司 | Cold twisting mould |
CN102581575A (en) * | 2012-03-21 | 2012-07-18 | 苏州新凌电炉有限公司 | Fabrication process of hexagonal flange toothed bolt |
CN105397189A (en) * | 2014-09-16 | 2016-03-16 | 郦忠 | Chamfering and rolling polishing die for hinge pin |
CN106984766A (en) * | 2016-01-21 | 2017-07-28 | 东莞市展赐精密五金制品厂 | The hex nut post processing technology of with groove |
CN106282819A (en) * | 2016-08-16 | 2017-01-04 | 宁波瑞国精机工业有限公司 | A kind of high-strength pin and processing method thereof |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
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CN111531093A (en) * | 2020-05-08 | 2020-08-14 | 深圳前沿装备有限公司 | Rubbing and extruding forming equipment for producing elastic core and technological process thereof |
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