CN111922799A - Sickle-shaped cutter polishing device and control method - Google Patents

Sickle-shaped cutter polishing device and control method Download PDF

Info

Publication number
CN111922799A
CN111922799A CN202010895020.5A CN202010895020A CN111922799A CN 111922799 A CN111922799 A CN 111922799A CN 202010895020 A CN202010895020 A CN 202010895020A CN 111922799 A CN111922799 A CN 111922799A
Authority
CN
China
Prior art keywords
wall
cutter
sickle
screw
sleeve
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.)
Pending
Application number
CN202010895020.5A
Other languages
Chinese (zh)
Inventor
杨国良
Original Assignee
杨国良
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 杨国良 filed Critical 杨国良
Priority to CN202010895020.5A priority Critical patent/CN111922799A/en
Publication of CN111922799A publication Critical patent/CN111922799A/en
Pending legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B3/00Sharpening cutting edges, e.g. of tools; Accessories therefor, e.g. for holding the tools
    • B24B3/36Sharpening cutting edges, e.g. of tools; Accessories therefor, e.g. for holding the tools of cutting blades
    • B24B3/44Sharpening cutting edges, e.g. of tools; Accessories therefor, e.g. for holding the tools of cutting blades of scythes or sickles
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B41/00Component parts such as frames, beds, carriages, headstocks
    • B24B41/02Frames; Beds; Carriages
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B41/00Component parts such as frames, beds, carriages, headstocks
    • B24B41/06Work supports, e.g. adjustable steadies
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B24GRINDING; POLISHING
    • B24BMACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B47/00Drives or gearings; Equipment therefor
    • B24B47/22Equipment for exact control of the position of the grinding tool or work at the start of the grinding operation

Abstract

The invention discloses a sickle bending cutter polishing device and a control method, and aims to solve the problems that the conventional bending sickle polishing mode is mainly based on the conventional manual polishing, the operation is complicated, the labor is consumed, the polishing effect is greatly influenced by the manual technical level, and the quick and convenient mechanical polishing is difficult to realize. According to the invention, the support structure formed by the drawing rod and the sleeve extends out of different heights under the action of the weight of the cutter, so that the top plates connected through the elastic ropes are connected into an arc-shaped rail, the cutter can be polished by sliding the wheel disc on the rail, the operation is convenient, the manpower is saved, the influence of manual technology level is avoided, and the effective polishing of the bent cutter is realized.

Description

Sickle-shaped cutter polishing device and control method
Technical Field
The invention relates to the technical field of grinding of curved sickles, in particular to a grinding device for a sickle curved cutter and a control method.
Background
The curved sickle is an agricultural implement for harvesting crops and mowing in rural areas, and comprises blades and a handle, wherein some blades are provided with small sawteeth and are generally used for harvesting rice, the curved sickle is widely used in some rural areas in the south of the Yangtze river at present, and after the curved sickle is used for a long time, passivation can occur, and the curved sickle needs to be polished.
The curved sickle is different from a common straight line-shaped cutter, the existing polishing mode of the curved sickle with the special shape still mainly uses traditional manual polishing, the operation is complex, the labor is consumed, the polishing effect is greatly influenced by the manual technical level, the rapid and convenient mechanical polishing is difficult to realize, the problem is difficult to solve in the prior patent, and therefore the problem is solved by the curved sickle-shaped cutter polishing device and the control method urgently.
Disclosure of Invention
Based on the technical problems that the existing grinding mode of the curved sickle is mainly based on traditional manual grinding, the operation is complex, the labor is consumed, the grinding effect is greatly influenced by the technical level of labor, and quick and convenient mechanical grinding is difficult to realize, the invention provides a grinding device of a sickle curved cutter and a control method.
In order to achieve the purpose, the invention adopts the following technical scheme:
a sickle-shaped cutter polishing device and a control method thereof comprise a bottom plate, an elastic rope, a transverse plate and a wheel disc, wherein a sleeve is fixed on the outer wall of the top of the bottom plate through a screw, a tension spring is arranged on the inner wall of the bottom of the sleeve, a draw-out rod is fixed on the top end of the tension spring through a screw, the draw-out rod is connected with the sleeve through a sleeve, an adjusting screw is connected with the outer wall of one side of the sleeve through a thread, a support is fixed on the outer wall of the draw-out rod through a screw, a groove is formed in the outer wall of the top of the support, a clamping groove is formed in the outer wall of the top of the draw-out rod, a fastening screw is connected with the outer wall of the clamping groove through a thread, a limiting spring is fixed on the outer wall of the top of the support through a screw, a track mechanism is, the utility model discloses a sharpening machine, including riser, bearing, the bottom of threaded rod, the spout has been seted up to one side outer wall of riser, the inner wall sliding connection of spout has the slider, and one side outer wall of slider has the motor through the fix with screw, the output shaft top of motor is provided with the mechanism of whetting a knife, one side outer wall of diaphragm has the threaded rod through the thread tightening, the bottom of threaded rod passes through the fix with screw and is connected with the top outer wall of motor, the bottom of threaded rod.
As a still further scheme of the invention: the track mechanism comprises a top plate, and a track is arranged on the outer wall of the top plate.
As a still further scheme of the invention: the support is characterized in that a groove is formed in the outer wall of the top of the support, and a support rod is connected to the inner wall of the groove through a rotating shaft.
As a still further scheme of the invention: the top end of the stay bar is connected with the bottom of the top plate through a hinge, and an elastic rope is fixed on the outer wall of one side of the top plate through a screw.
As a still further scheme of the invention: it is characterized in that the wheel disc is matched with the track.
As a still further scheme of the invention: the knife sharpening mechanism comprises an adjusting rod, and the adjusting rod is connected with an output shaft of the motor through threads.
As a still further scheme of the invention: one end of the adjusting rod is fixed with a knife stone through a screw.
As a still further scheme of the invention: the utility model provides a motor that sets up among hook bending cutter grinding device passes through external power supply circular telegram, during the use, put into the draw-in groove with the blade, the tension spring intensity that the sleeve inner wall set up is less, make the pole of taking out of different positions under the action of gravity of cutter stretch out different height, carry out the high fixed with sleeve and pole of taking out through adjusting screw at last, it is tight to make the cutter pressed from both sides tightly through fastening screw, adjust the upper and lower height of whetstone through rotating the crank this moment, adjust the transverse distance of whetstone and cutter through adjusting the pole, operating personnel both hands are held both sides handle and are promoted forward and make the rim plate slide at orbital inner wall, realize polishing to the cutter through reciprocating motion back and forth, polish the opposite side of adjustment direction to the cutter again after one side finishes polishing, realize polishing to the bending cutter.
The invention has the beneficial effects that:
1. by arranging the sleeve, the drawing rod, the top plate, the track and the wheel disc, the support structure formed by the drawing rod and the sleeve extends out of different heights under the action of the weight of the cutter, so that the top plates connected through the elastic ropes are connected into an arc-shaped track, and the grinding of the cutter can be realized by sliding the wheel disc on the track, so that the cutter grinding machine is convenient to operate, labor-saving, free of manual technical level influence and capable of effectively grinding the bent cutter;
2. by arranging the vertical plate, the sliding groove, the threaded rod, the transverse plate, the adjusting rod, the motor and the knife stone, the crank is rotated to drive the threaded rod to rotate, so that the motor can move up and down through the sliding groove, the transverse position of the knife stone is adjusted under the action of the adjusting rod, the curved cutters with different thicknesses and different widths can be conveniently polished, and the practicability is high;
3. through setting up stretch cord, roof, spacing spring, vaulting pole and track, spacing spring and vaulting pole combined action make the direction and the change of longitudinal height certain angle of roof, the arc shape that the roof formed through stretch cord links to each other is close to the shape of bending cutter, can change according to the shape adaptability of bending cutter.
Drawings
FIG. 1 is a perspective view of a sickle-shaped knife grinding apparatus and a control method thereof according to the present invention;
FIG. 2 is a perspective view of an adjusting rod portion in the sickle-shaped knife grinding apparatus and the control method according to the present invention;
FIG. 3 is a perspective view of a support rod portion in the sickle-shaped knife grinding apparatus and the control method according to the present invention;
FIG. 4 is a perspective view of a chute portion of a sickle-shaped knife grinding apparatus and a control method according to the present invention;
FIG. 5 is a perspective view of a groove portion in a sickle-shaped knife dressing apparatus and a control method according to the present invention.
In the figure: the device comprises a sleeve 1, an adjusting screw 2, a drawing rod 3, a support 4, a clamping groove 5, a fastening screw 6, a vertical plate 7, a sliding groove 8, a motor 9, a knife stone 10, an adjusting rod 11, a threaded rod 12, a crank 13, a transverse plate 14, a support rod 15, a top plate 16, a limiting spring 17, an elastic rope 18, a track 19, a handle 20, a wheel disc 21, a bottom plate 22 and a groove 23.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments.
Referring to fig. 1-5, a sickle-shaped cutter polishing device and a control method thereof, comprising a bottom plate 22, an elastic rope 18, a transverse plate 14 and a wheel disc 21, wherein the outer wall of the top of the bottom plate 22 is fixed with a sleeve 1 through a screw, the inner wall of the bottom of the sleeve 1 is provided with a tension spring, the top end of the tension spring is fixed with a draw-out rod 3 through a screw, the draw-out rod 3 is connected with the sleeve 1 through a sleeve, the outer wall of one side of the sleeve 1 is connected with an adjusting screw 2 through a screw thread, the outer wall of the draw-out rod 3 is fixed with a bracket 4 through a screw, the outer wall of the top of the bracket 4 is provided with a groove 23, the outer wall of the top of the draw-out rod 3 is provided with a clamping groove 5, the outer wall of the clamping groove 5 is connected with a fastening screw 6 through a screw thread, the, the one end of handle 20 is passed through the fix with screw and is had riser 7, spout 8 has been seted up to one side outer wall of riser 7, the inner wall sliding connection of spout 8 has the slider, one side outer wall of slider has motor 9 through the fix with screw, motor 9's output shaft top is provided with the mechanism of whetting a knife, one side outer wall of diaphragm 14 passes through threaded fixation threaded rod 12, the bottom of threaded rod 12 passes through the bearing with motor 9's top outer wall and is connected, the bottom of threaded rod 12 passes through the fix with screw and has crank 13.
In the invention, the track mechanism comprises a top plate 16, and the outer wall of the top plate 16 is provided with a track 19.
In the invention, the outer wall of the top of the bracket 4 is provided with a groove 23, and the inner wall of the groove 23 is connected with a support rod 15 through a rotating shaft.
In the invention, the top end of the stay bar 15 is connected with the bottom of the top plate 16 through a hinge, and the elastic rope 18 is fixed on the outer wall of one side of the top plate 16 through a screw.
In the present invention, the wheel disc 21 is fitted with the rail 19.
In the invention, the knife sharpening mechanism comprises an adjusting rod 11, and the adjusting rod 11 is connected with an output shaft of the motor 9 through threads.
In the present invention, a whetstone 10 is fixed to one end of an adjusting lever 11 by a screw.
In the invention, the motor 9 arranged in the sickle-shaped cutter polishing device is electrified by an external power supply, when in use, the cutter is placed in the clamping groove 5, the tension spring arranged on the inner wall of the sleeve 1 has lower strength, the drawing rods 3 at different positions extend out to different heights under the action of the gravity of the cutter, the sleeve 1 and the drawing rods 3 are fixed in height through the adjusting screws 2, the cutter is clamped through the fastening screws 6, the vertical height of the knife stone 10 is adjusted by rotating the crank 13, the transverse distance between the whetstone 10 and the knife is adjusted by the adjusting rod 11, the operator holds the grips 20 at both sides with both hands to push forward so that the wheel disc 21 slides on the inner wall of the track 19, the grinding of the cutter is realized through reciprocating motion, the cutter is taken out after one side is ground, the direction is adjusted, and the other side of the cutter is ground, so that the grinding of the bent cutter is realized.
When in use, the motor 9 is electrified through the external power supply, when in use, the cutter is placed in the clamping groove 5, the tension spring arranged on the inner wall of the sleeve 1 has lower strength, the drawing rods 3 at different positions extend out to different heights under the action of the gravity of the cutter, the sleeve 1 and the drawing rods 3 are fixed in height by rotating the adjusting screw 2, the cutter is clamped by rotating the fastening screw 6, the vertical height of the knife stone 10 is adjusted by rotating the crank 13, the lateral distance between the whetstone 10 and the cutter is adjusted by the adjusting lever 11, so that the whetstone 10 can be brought into contact with the cutter, meanwhile, the operator holds the two side grips 20 with both hands and pushes forwards to make the wheel disc 21 slide on the inner wall of the track 19, the grinding of the cutter is realized through reciprocating motion, the cutter is taken out after one side is ground, the direction is adjusted, and the other side of the cutter is ground, so that the grinding of the bent cutter is realized.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.

Claims (8)

1. The utility model provides a hook bending cutter grinding device, includes bottom plate (22), stretch cord (18), diaphragm (14) and rim plate (21), its characterized in that, the top outer wall of bottom plate (22) has sleeve (1) through the fix with screw, the bottom inner wall of sleeve (1) is provided with tension spring, and tension spring's top has pole (3) through the fix with screw, pole (3) are connected through cup jointing with sleeve (1) in the pole, there is adjusting screw (2) one side outer wall of sleeve (1) through threaded connection, the outer wall of pole (3) has support (4) through the fix with screw, the top outer wall of support (4) is seted up flutedly (23), draw-in groove (5) has been seted up to the top outer wall of pole (3), there is fastening screw (6) through threaded connection in the outer wall of draw-in groove (5), the top outer wall of support (4) passes through the fix with screw limited position spring (17), the top of spacing spring (17) is provided with track mechanism, the through-hole has been seted up to one side outer wall of rim plate (21), and the inner wall of through-hole is connected with handle (20) through the bearing, the one end of handle (20) has riser (7) through the fix with screw, spout (8) have been seted up to one side outer wall of riser (7), the inner wall sliding connection of spout (8) has the slider, and one side outer wall of slider has motor (9) through the fix with screw, the output shaft top of motor (9) is provided with the mechanism of whetting a knife, one side outer wall of diaphragm (14) has threaded rod (12) through the threaded fixation, the bottom of threaded rod (12) passes through the bearing with the top outer wall of motor (9) and is connected, the bottom of threaded rod (12) has crank (.
2. The sickle-shaped knife grinding device according to claim 1, characterized in that the rail mechanism comprises a top plate (16), and the top outer wall of the top plate (16) is provided with a rail (19).
3. The sickle-shaped knife grinding device and the control method according to claim 1 are characterized in that a groove (23) is formed in the outer wall of the top of the support (4), and a support rod (15) is connected to the inner wall of the groove (23) through a rotating shaft.
4. The sickle-shaped knife grinding device according to claim 3, characterized in that the top end of the stay bar (15) is hinged with the bottom of the top plate (16), and the elastic cord (18) is fixed on the outer wall of one side of the top plate (16) through a screw.
5. Sickle curve tool sharpening device and control method according to claim 1, characterized in that the wheel disc (21) coincides with the track (19).
6. The sickle-shaped knife grinding device according to claim 1, characterized in that the knife grinding mechanism comprises an adjusting rod (11), and the adjusting rod (11) is in threaded connection with the output shaft of the motor (9).
7. The sickle-shaped knife sharpening device according to claim 6, characterized in that a sharpening stone (10) is fixed to one end of the adjustment rod (11) by means of screws.
8. A control method of a sickle-shaped cutter polishing device is characterized in that a motor (9) arranged in the sickle-shaped cutter polishing device is electrified through an external power supply, when the sickle-shaped cutter polishing device is used, a blade is placed in a clamping groove (5), a tension spring arranged on the inner wall of a sleeve (1) is small in strength, draw rods (3) at different positions extend out to different heights under the action of the gravity of a cutter, finally the sleeve (1) and the draw rods (3) are fixed in height through adjusting screws (2), the cutter is clamped through fastening screws (6), the upper height and the lower height of a grinding stone (10) are adjusted through rotating a crank (13), the transverse distance between the grinding stone (10) and the cutter is adjusted through adjusting rods (11), an operator holds handles (20) at two sides to push forwards to enable a wheel disc (21) to slide on the inner wall of a track (19), and polishes the cutter through reciprocating motion back and forth, and after one side is polished, the cutter is taken out and the direction is adjusted to polish the other side of the cutter, so that the curved cutter is polished.
CN202010895020.5A 2020-08-31 2020-08-31 Sickle-shaped cutter polishing device and control method Pending CN111922799A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202010895020.5A CN111922799A (en) 2020-08-31 2020-08-31 Sickle-shaped cutter polishing device and control method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202010895020.5A CN111922799A (en) 2020-08-31 2020-08-31 Sickle-shaped cutter polishing device and control method

Publications (1)

Publication Number Publication Date
CN111922799A true CN111922799A (en) 2020-11-13

Family

ID=73309669

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202010895020.5A Pending CN111922799A (en) 2020-08-31 2020-08-31 Sickle-shaped cutter polishing device and control method

Country Status (1)

Country Link
CN (1) CN111922799A (en)

Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2549653A1 (en) * 1974-11-05 1976-05-13 Sumitomo Electric Industries METHOD OF MANUFACTURING AN ANTENNA REFLECTOR
JPH07136946A (en) * 1993-11-17 1995-05-30 Yamamoto Suiatsu Kogyosho:Kk Assembly work jig
JP2005342875A (en) * 2004-06-07 2005-12-15 Ricoh Co Ltd Curved surface machining device, optical element and optical element mold formed by using the device, and calibration method of parallel link mechanism
KR20130112251A (en) * 2012-04-03 2013-10-14 정천섭 The surface polishing machine
CN203945206U (en) * 2014-07-26 2014-11-19 江永科刃五金制品有限责任公司 A kind of curved edge processing unit (plant) of cutter
CN204171802U (en) * 2014-09-28 2015-02-25 浙江中集轴承有限公司 Molding cutter adjustable type reconditioning seat
CN206316901U (en) * 2016-11-24 2017-07-11 东莞市大顺拉链五金配件有限公司 A kind of metal zip fastener tooth head polishing machine
CN107649951A (en) * 2017-11-03 2018-02-02 张宇航 A kind of grinding clamp of diamond cutter
CN107738143A (en) * 2017-10-26 2018-02-27 袁文林 End face sanding apparatus is used in a kind of reaping hook processing
CN208374889U (en) * 2018-04-13 2019-01-15 德阳万源旭鸿机电科技发展有限公司 A kind of CNC Cutter Grinding Machine Tool Processing Room top plate wiper mechanism
CN209565895U (en) * 2019-01-02 2019-11-01 临安宇杰精密制品有限公司 A kind of full-automatic multi-functional knife sharpening device
CN210388547U (en) * 2019-07-31 2020-04-24 杭州海内自动化设备有限公司 Arc sword cutting edge grinding device

Patent Citations (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2549653A1 (en) * 1974-11-05 1976-05-13 Sumitomo Electric Industries METHOD OF MANUFACTURING AN ANTENNA REFLECTOR
JPH07136946A (en) * 1993-11-17 1995-05-30 Yamamoto Suiatsu Kogyosho:Kk Assembly work jig
JP2005342875A (en) * 2004-06-07 2005-12-15 Ricoh Co Ltd Curved surface machining device, optical element and optical element mold formed by using the device, and calibration method of parallel link mechanism
KR20130112251A (en) * 2012-04-03 2013-10-14 정천섭 The surface polishing machine
CN203945206U (en) * 2014-07-26 2014-11-19 江永科刃五金制品有限责任公司 A kind of curved edge processing unit (plant) of cutter
CN204171802U (en) * 2014-09-28 2015-02-25 浙江中集轴承有限公司 Molding cutter adjustable type reconditioning seat
CN206316901U (en) * 2016-11-24 2017-07-11 东莞市大顺拉链五金配件有限公司 A kind of metal zip fastener tooth head polishing machine
CN107738143A (en) * 2017-10-26 2018-02-27 袁文林 End face sanding apparatus is used in a kind of reaping hook processing
CN107649951A (en) * 2017-11-03 2018-02-02 张宇航 A kind of grinding clamp of diamond cutter
CN208374889U (en) * 2018-04-13 2019-01-15 德阳万源旭鸿机电科技发展有限公司 A kind of CNC Cutter Grinding Machine Tool Processing Room top plate wiper mechanism
CN209565895U (en) * 2019-01-02 2019-11-01 临安宇杰精密制品有限公司 A kind of full-automatic multi-functional knife sharpening device
CN210388547U (en) * 2019-07-31 2020-04-24 杭州海内自动化设备有限公司 Arc sword cutting edge grinding device

Similar Documents

Publication Publication Date Title
US6786806B2 (en) Rotary mower blade sharpener
CN206084615U (en) Semi -automatic cutting edge processor
CN208342936U (en) A kind of off-standard size plate cutting device
CN2910444Y (en) Grinder for wolfram steel saw bit
CN111922799A (en) Sickle-shaped cutter polishing device and control method
CN208322883U (en) It is a kind of for processing the grinding attachment of polycrystal diamond cutter
CN211029262U (en) Portable automatic knife grinder
CN212918686U (en) Edging device for cutter production
US4299142A (en) Grinding machine with reorientable chain holding clamp
CN210703918U (en) Automatic knife sharpening device
CN208276621U (en) A kind of knife sharpener convenient for adjusting
US2562578A (en) Lawn mower sharpening machine
CN209616058U (en) Cutting machine is used in a kind of processing of jewelry
CN107952225B (en) A kind of curling stone slide-helper
CN205703752U (en) A kind of abrasive machine
CN215824986U (en) Polishing device for watch band batch edge
CN2616339Y (en) Electric knife sharpener
CN216576962U (en) High-efficient blade production skiving system
CN208001567U (en) Crop harvester quick knife sharpening device and a kind of crop harvester manually
CN210909248U (en) Blade fixing device of knife grinder
CN208601248U (en) A kind of automatic grinding device
CN212192542U (en) Male and female groove polishing and fixing mechanism and male and female groove polishing and fixing device
CN214394457U (en) Die-cutting rule fine grinding device convenient to position
CN208276754U (en) A kind of knife sharpener blade fixing device
CN213379541U (en) Needle cutting machine

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination