CN106985006A - A kind of double bistrique type knife sharpeners of two-sided cooling and its sharpening method - Google Patents

A kind of double bistrique type knife sharpeners of two-sided cooling and its sharpening method Download PDF

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Publication number
CN106985006A
CN106985006A CN201710240510.XA CN201710240510A CN106985006A CN 106985006 A CN106985006 A CN 106985006A CN 201710240510 A CN201710240510 A CN 201710240510A CN 106985006 A CN106985006 A CN 106985006A
Authority
CN
China
Prior art keywords
slide
cutter
type knife
sided cooling
lower platen
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
CN201710240510.XA
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Chinese (zh)
Inventor
谢明礼
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Ningbo Tianhe Electric Tool Coltd
Original Assignee
Ningbo Tianhe Electric Tool Coltd
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 Ningbo Tianhe Electric Tool Coltd filed Critical Ningbo Tianhe Electric Tool Coltd
Priority to CN201710240510.XA priority Critical patent/CN106985006A/en
Publication of CN106985006A publication Critical patent/CN106985006A/en
Pending legal-status Critical Current

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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
    • B24B1/00Processes of grinding or polishing; Use of auxiliary equipment in connection with such processes
    • 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
    • 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
    • B24B49/00Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation
    • B24B49/12Measuring or gauging equipment for controlling the feed movement of the grinding tool or work; Arrangements of indicating or measuring equipment, e.g. for indicating the start of the grinding operation involving optical means
    • 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
    • B24B55/00Safety devices for grinding or polishing machines; Accessories fitted to grinding or polishing machines for keeping tools or parts of the machine in good working condition
    • B24B55/02Equipment for cooling the grinding surfaces, e.g. devices for feeding coolant

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Finish Polishing, Edge Sharpening, And Grinding By Specific Grinding Devices (AREA)

Abstract

The invention discloses a kind of double bistrique type knife sharpeners of two-sided cooling and its sharpening method, including body, slide rail and the second drive device are provided with the upper side of the body, second drive device is installed on one end of slide rail, the slide rail is provided with slide, the lower section of the slide is provided with the chute for clamping slide rail, and the drive end of second drive device is connected on slide, and the top of the slide is provided with installing plate;Invention additionally discloses a kind of double bistrique type knife sharpeners of two-sided cooling sharpening method, comprise the following steps:Take on cutter to be processed, arrangement of tool and lower platen;Rotation dish is rotated, while threaded rod is rotated, drives top board to move down, top board and lower platen are by cutter holding.The electric elements of whole device of the present invention start running, and now infrared inductor and pressure sensitive device will sense the position of cutter hub, reach the effect polished cutter hub and cooled down, so as to realize the effect that efficiently quickly intelligent polishing is cooled down.

Description

A kind of double bistrique type knife sharpeners of two-sided cooling and its sharpening method
Technical field
The present invention relates to knife sharpener technical field, more particularly to a kind of double bistrique type knife sharpeners of two-sided cooling and its sharpening side Method.
Background technology
Knife sharpener claims end face knife grinder earliest, and its structure is mainly planer-type.Mainly for:Sharpening center, forest industry, Printing house, papermaking plastics, book and periodical printing center, medium-sized sharpening Fang Deng mechanisms enterprise customer.Main Types:Full-automatic tool sharpener, Accurate knife sharpener, numerical control knife sharpener, woodworking knife sharpener, scraper knife sharpener special, printing knife sharpener, paper cutter knife sharpener, many work( Energy knife sharpener, double bistrique knife sharpeners, circular knife grinder etc., but the sander of market can not realize quick pair well at present The effect that face is polished and cooled down so that the operating efficiency of knife sharpener is low, so as to cause inconvenience to user.
The content of the invention
The technical problem existed based on background technology, the present invention propose a kind of double bistrique type knife sharpeners of two-sided cooling and its Sharpening method.
It is provided with the upper side of a kind of double bistrique type knife sharpeners of two-sided cooling proposed by the present invention, including body, the body Slide rail and the second drive device, second drive device are installed on one end of slide rail, and the slide rail is provided with slide, the cunning The lower section of seat is provided with the chute for clamping slide rail, and the drive end of second drive device is connected on slide, the slide Top be provided with installing plate, side of the installing plate away from slide is connected with multiple first gag lever posts, first gag lever post One end away from installing plate, which is connected with first driving means, first gag lever post, is socketed with connecting seat, first driving The drive end of device is connected on connecting seat by catch bar, and the side of the connecting seat is connected with processing plate, the processing plate The side of remote connecting seat be arranged with two polishing rollers and two grip blocks, one end of the polishing roller is connected with the first limit Position block, one end of the grip block is connected with the second limited block, and the side of the processing plate is respectively provided with clamping first and limited The first stopper slot and the second stopper slot of position block and the second limited block, the relative side of the grip block are provided with cooling device, Opposite side is provided with grip slipper above the body.
Preferably, the upper and lower ends of the processing plate are symmetrically installed with the 3rd drive device and adjusting rod.
Preferably, the drive end of the 3rd drive device is connected on the first limited block, and one end of the adjusting rod is worn Cross processing plate and be threadedly coupled with the second limited block.
Preferably, the grip slipper includes mounting seat, and the top of the mounting seat is provided with above lower platen, the lower platen Provided with threaded rod, the one end of the threaded rod away from lower platen is connected with rotation dish, and the lower section two ends of the rotation dish pass through Two gag lever posts are connected with lower platen.
Preferably, top board is provided between the rotation dish and lower platen, the top board, which is provided with, to be used for through screw thread The mounting hole of bar and gag lever post, the side of the rotation dish is provided with the annular slot for the gag lever post of clamping second.
Preferably, controller is provided with the body, and one end of slide rail is provided with block, the side of the block is provided with Pressure sensitive device is installed on infrared inductor, the polishing roller.
Preferably, the controller respectively with first driving means, the second drive device, the second drive device, infrared sense Device and pressure sensitive device is answered to electrically connect.
Invention additionally discloses a kind of double bistrique type knife sharpeners of two-sided cooling sharpening method, comprise the following steps:
Take on cutter to be processed, arrangement of tool and lower platen;Rotation dish is rotated, while threaded rod is rotated, in drive Pressing plate is moved down, and top board and lower platen are by cutter holding;Adjust connecting seat height so that two polishing rollers between height with The height of cutter is in same level;Open the second drive device, drive slide movement, cutter by two polishing rollers it Between;Treat that cutter completely disengages from two polishing rollers, then cool down cutter, finally remove cutter.
It is easy to operate in the present invention, it is simple in construction, it can be entered by the way that cutter hub is held between train wheel bridge and lower plate And by rotating rotation dish so that train wheel bridge is moved down, so as to cutter hub is held between train wheel bridge and lower plate, so as to ensure that Cutter hub can be held on grip slipper with fast and stable, and then is turned on the power switch, so that the electric elements of whole device are opened Begin operating, now infrared inductor and pressure sensitive device will sense the position of cutter hub, reach to cutter hub carry out polishing and The effect of cooling, so as to realize the effect that efficiently quickly intelligent polishing is cooled down.
Brief description of the drawings
Fig. 1 is a kind of structural representation of the double bistrique type knife sharpeners of two-sided cooling proposed by the present invention;
Fig. 2 is a kind of holding-seat structure schematic diagram of the double bistrique type knife sharpeners of two-sided cooling proposed by the present invention;
Fig. 3 is a kind of processing plate structure schematic diagram of the double bistrique type knife sharpeners of two-sided cooling proposed by the present invention.
In figure:1 body, 2 mounting seats, 3 polishing rollers, 4 processing plates, 5 first driving means, 6 first gag lever posts, 7 connecting seats, 8 installing plates, 9 catch bars, 10 second drive devices, 11 slides, 12 slide rails, 13 top boards, 14 rotation dish, 15 threaded rods, 16 Two gag lever posts, 17 the 3rd drive devices, 18 adjusting rods, 19 grip blocks, 20 cooling devices, 21 lower platens.
Embodiment
The present invention is made with reference to specific embodiment further to explain.
Embodiment one
A kind of double bistrique type knife sharpeners of two-sided cooling, including body 1, the upper side of body 1 is driven provided with slide rail 12 and second Dynamic device 10, the second drive device 10 is installed on one end of slide rail 12, and slide rail 12 is provided with slide 11, and the lower section of slide 11 is provided with For the chute of clamping slide rail 12, the drive end of the second drive device 10 is connected on slide 11, and the top of slide 11 is provided with peace Fill plate 8, side of the installing plate 8 away from slide 11 is connected with multiple first gag lever posts 6, the first gag lever post 6 away from installing plate 8 one End, which is connected with first driving means 5, the first gag lever post 6, is socketed with connecting seat 7, and the drive end of first driving means 5 is by pushing away Lever 9 is connected on connecting seat 7, and the side of connecting seat 7 is connected with processing plate 4, and the upper and lower ends of processing plate 4 are symmetrically installed with the Three drive devices 17 and adjusting rod 18, the drive end of the 3rd drive device 17 are connected on the first limited block, and the one of adjusting rod 18 End is threadedly coupled through processing plate 4 and with the second limited block, can adjust two by the 3rd drive device 17 and adjusting rod 18 The spacing polished between roller 3 and two grip blocks 19, so that better, the processing plate of polishing and the cooling of cutter hub The side of 4 remote connecting seat 7 is arranged with two polishing rollers 3 and two grip blocks 19, and one end of polishing roller 3 is connected with first Limited block, one end of grip block 19 is connected with the second limited block, and the side of processing plate 4 is respectively provided with the limited block of clamping first With the first stopper slot and the second stopper slot of the second limited block, the relative side of grip block 19 is provided with cooling device 20, cooling Device 20 is dividing wall type heat exchanger, and hot two fluid is separated by one layer of solid wall surface, do not mixed, and heat exchange is carried out by partition, The cutter polished, by being exchanged heat between two cooling devices 20, the temperature of tool surface can rapidly be lowered, The top opposite side of body 1 is provided with grip slipper, and grip slipper includes mounting seat 2, and the top of mounting seat 2 is provided with lower platen 21, pushed The top of plate 21 is provided with threaded rod 15, and the one end of threaded rod 15 away from lower platen 21 is connected with rotation dish 14, the lower section of rotation dish 14 Two ends are connected by the second gag lever post 16 with lower platen 21, and top board 13, top board are provided between rotation dish 14 and lower platen 21 13 are provided with for the mounting hole through the gag lever post 16 of threaded rod 15 and second, and the side of rotation dish 14 is provided with spacing for clamping The annular slot of bar 16 so that blade to be processed more fast clamp increases blade between train wheel bridge 13 and lower plate 21 Clamping effect, controller is provided with body 1, and one end of slide rail 12 is provided with block, the side of block is provided with infrared induction Pressure sensitive device is installed on device, polishing roller 3, controller respectively with first driving means 5, the second drive device 10, the Two drive devices 17, infrared inductor and the electrical connection of pressure sensitive device, the intellectuality of increase whole device and automation effect Really, the effect that polishing roller 3 and cooling device 20 can be driven to be polished cutter hub and cooled by infrared inductor, Realize the effect of rapid processing cutter.
The sharpening method of the double bistrique type knife sharpeners of described two-sided cooling, comprises the following steps:Cutter to be processed is taken, is put Put on cutter and lower platen 21;Rotation dish 14 is rotated, while threaded rod 15 is rotated, drives top board 13 to move down, top board 13 With lower platen 21 by cutter holding;Adjust the height of connecting seat 7 so that the height of height and cutter between two polishing rollers 3 In same level;The second drive device 10 is opened, drives slide 11 to move, cutter is by between two polishing rollers 3;Treat Cutter completely disengages from two polishing rollers 3, then cools down cutter, finally removes cutter.
The foregoing is only a preferred embodiment of the present invention, but protection scope of the present invention be not limited thereto, Any one skilled in the art the invention discloses technical scope in, technique according to the invention scheme and its Inventive concept is subject to equivalent substitution or change, should all be included within the scope of the present invention.

Claims (8)

1. a kind of double bistrique type knife sharpeners of two-sided cooling, including body (1), it is characterised in that set at the upper side of the body (1) There are slide rail (12) and the second drive device (10), second drive device (10) is installed on one end of slide rail (12), the cunning Rail (12) is provided with slide (11), and the lower section of the slide (11) is provided with the chute for clamping slide rail (12), and described second drives The drive end of dynamic device (10) is connected on slide (11), and the top of the slide (11) is provided with installing plate (8), the installing plate (8) side away from slide (11) is connected with multiple first gag lever posts (6), the remote installing plate (8) of first gag lever post (6) One end is connected with first driving means (5), first gag lever post (6) and is socketed with connecting seat (7), the first driving means (5) drive end is connected on connecting seat (7) by catch bar (9), and the side of the connecting seat (7) is connected with processing plate (4), The side of the remote connecting seat (7) of the processing plate (4) is arranged with two polishing rollers (3) and two grip blocks (19), described One end of polishing roller (3) is connected with the first limited block, and one end of the grip block (19) is connected with the second limited block, the processing The side of plate (4) is respectively provided with the first stopper slot and the second stopper slot of the limited block of clamping first and the second limited block, institute State grip block (19) relative side and cooling device (20) is installed, body (1) top opposite side is provided with grip slipper.
2. a kind of double bistrique type knife sharpeners of two-sided cooling according to claim 1, it is characterised in that the processing plate (4) Upper and lower ends be symmetrically installed with the 3rd drive device (17) and adjusting rod (18).
3. the double bistrique type knife sharpeners of a kind of two-sided cooling according to claim 1 or 2, it is characterised in that the described 3rd drives The drive end of dynamic device (17) is connected on the first limited block, and one end of the adjusting rod (18) is through processing plate (4) and with the Two limited blocks are threadedly coupled.
4. the double bistrique type knife sharpeners of a kind of two-sided cooling according to claim 1, it is characterised in that the grip slipper includes Mounting seat (2), the top of the mounting seat (2), which is provided with above lower platen (21), the lower platen (21), is provided with threaded rod (15), The one end of the threaded rod (15) away from lower platen (21) is connected with rotation dish (14), and the lower section two ends of the rotation dish (14) lead to The second gag lever post (16) is crossed to be connected with lower platen (21).
5. a kind of double bistrique type knife sharpeners of two-sided cooling according to claim 4, it is characterised in that the rotation dish (14) Top board (13) is provided between lower platen (21), the top board (13), which is provided with, to be used to limit through threaded rod (15) and second The mounting hole of position bar (16), the side of the rotation dish (14) is provided with the annular slot for the gag lever post of clamping second (16).
6. the double bistrique type knife sharpeners of a kind of two-sided cooling according to claim 1, it is characterised in that in the body (1) One end provided with controller, and slide rail (12) is provided with block, and the side of the block is provided with infrared inductor, the polishing Roller is provided with pressure sensitive device on (3).
7. a kind of double bistrique type knife sharpeners of two-sided cooling according to claim 1 or 6, it is characterised in that the controller Respectively with first driving means (5), the second drive device (10), the second drive device (17), infrared inductor and feeling of stress Device is answered to electrically connect.
8. a kind of a kind of sharpening method of the double bistrique type knife sharpeners of two-sided cooling according to claim 1-7, its feature exists In comprising the following steps:
Take on cutter to be processed, arrangement of tool and lower platen (21);Rotation dish (14) is rotated, it is same that threaded rod (15) is rotated When, drive top board (13) to move down, top board (13) and lower platen (21) are by cutter holding;The height of connecting seat (7) is adjusted, is made The height for obtaining the height between two polishing rollers (3) and cutter is in same level;Open the second drive device (10), band Dynamic slide (11) is mobile, and cutter is by between two polishing rollers (3);Treat that cutter completely disengages from two polishing rollers (3), then cooling knife Tool, finally removes cutter.
CN201710240510.XA 2017-04-13 2017-04-13 A kind of double bistrique type knife sharpeners of two-sided cooling and its sharpening method Pending CN106985006A (en)

Priority Applications (1)

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CN201710240510.XA CN106985006A (en) 2017-04-13 2017-04-13 A kind of double bistrique type knife sharpeners of two-sided cooling and its sharpening method

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Application Number Priority Date Filing Date Title
CN201710240510.XA CN106985006A (en) 2017-04-13 2017-04-13 A kind of double bistrique type knife sharpeners of two-sided cooling and its sharpening method

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108214120A (en) * 2018-01-08 2018-06-29 李正蒙 A kind of axe milling robot
CN114714177A (en) * 2022-03-29 2022-07-08 重庆市大足区钜豪精密刀锯有限公司 Double-turntable multi-station knife sharpener for manufacturing high-end equipment

Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2409009Y (en) * 2000-03-17 2000-12-06 黄计高 Double-face edge sharpener
CN2435183Y (en) * 2000-07-13 2001-06-20 黄计高 Hanging double-face lapper
RU2009132252A (en) * 2009-08-26 2011-03-10 Роман Валерьевич Жигалов (RU) ELECTROMAGNETIC DEVICE FOR PREVENTING OPERATIONAL IMBALANCES OF END GRINDING CIRCLES
CN102873597A (en) * 2012-10-07 2013-01-16 呼长波 Electric double-sided knife sharpener
CN204843722U (en) * 2015-05-20 2015-12-09 黄正华 Two -sided flat sharpening sword machine
CN105619204A (en) * 2013-06-04 2016-06-01 项大清 Diamond tool bit bevel face grinding device
KR20160127504A (en) * 2015-04-27 2016-11-04 박상철 Clamping vice of work piece
CN106119435A (en) * 2016-08-26 2016-11-16 重庆绿草缘皮革制品有限公司 Dedusting buffing integral type two-sided buffing system
CN106271911A (en) * 2016-09-24 2017-01-04 成都创慧科达科技有限公司 A kind of cutter sanding apparatus

Patent Citations (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN2409009Y (en) * 2000-03-17 2000-12-06 黄计高 Double-face edge sharpener
CN2435183Y (en) * 2000-07-13 2001-06-20 黄计高 Hanging double-face lapper
RU2009132252A (en) * 2009-08-26 2011-03-10 Роман Валерьевич Жигалов (RU) ELECTROMAGNETIC DEVICE FOR PREVENTING OPERATIONAL IMBALANCES OF END GRINDING CIRCLES
CN102873597A (en) * 2012-10-07 2013-01-16 呼长波 Electric double-sided knife sharpener
CN105619204A (en) * 2013-06-04 2016-06-01 项大清 Diamond tool bit bevel face grinding device
KR20160127504A (en) * 2015-04-27 2016-11-04 박상철 Clamping vice of work piece
CN204843722U (en) * 2015-05-20 2015-12-09 黄正华 Two -sided flat sharpening sword machine
CN106119435A (en) * 2016-08-26 2016-11-16 重庆绿草缘皮革制品有限公司 Dedusting buffing integral type two-sided buffing system
CN106271911A (en) * 2016-09-24 2017-01-04 成都创慧科达科技有限公司 A kind of cutter sanding apparatus

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108214120A (en) * 2018-01-08 2018-06-29 李正蒙 A kind of axe milling robot
CN114714177A (en) * 2022-03-29 2022-07-08 重庆市大足区钜豪精密刀锯有限公司 Double-turntable multi-station knife sharpener for manufacturing high-end equipment

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Application publication date: 20170728