CN113941896B

CN113941896B - Casting machining center

Info

Publication number: CN113941896B
Application number: CN202111387756.2A
Authority: CN
Inventors: 陈晓锋; 吕健; 唐晓明; 吕国富
Original assignee: Wenzhou Ouhai Chaoguang Valve Machinery Casting Factory
Current assignee: Wenzhou Ouhai Chaoguang Valve Machinery Casting Factory
Priority date: 2021-11-22
Filing date: 2021-11-22
Publication date: 2023-03-03
Anticipated expiration: 2041-11-22
Also published as: CN113941896A

Abstract

The application discloses foundry goods machining center relates to the field of foundry goods processing, and it includes the support frame, be provided with the base on the support frame, the collection bits groove that is used for collecting iron fillings is offered to the up end of base, the one end that collects the bits groove axial is the discharge gate, the base all is provided with in the both sides in collection bits groove and is used for discharging the mechanism that gathers materials in the collection bits groove with iron fillings, the base is provided with in the collection bits inslot and is used for following the discharge pushing equipment in collection bits groove with iron fillings. When needing to clear up the iron fillings on the base, earlier concentrate the iron fillings on the base to an album bits inslot through the mechanism that gathers materials, release the iron fillings in the chip collection groove through pushing equipment after that to accomplish the clearance of iron fillings, improve the cleaning efficiency of iron fillings, also reduce staff's work load simultaneously.

Description

Casting machining center

Technical Field

The application relates to the field of casting machining, in particular to a casting machining center.

Background

The casting is a metal molding object obtained by various casting methods, namely, the smelted liquid metal is poured into a pre-prepared casting mould by pouring, injection, suction or other casting methods, and after cooling, the casting is ground and other subsequent processing means, and the object with certain shape, size and performance is obtained. People often process the casting through a casting processing center, the processing center usually comprises a base, a processing mechanism for processing the casting and a plurality of working tables for clamping the casting, and after the casting is fixed on the working tables, the processing mechanism cuts the casting and the like.

With respect to the above-described related art, the inventors consider that the following drawbacks exist: can produce more iron fillings when the foundry goods cuts, iron fillings often directly drop to the base on, follow-up needs the staff to clean the clearance of beating to the iron fillings on the base, and the clearance inefficiency consequently remains to be improved.

Disclosure of Invention

In order to improve the cleaning efficiency of iron fillings, this application provides a foundry goods machining center.

The utility model provides a foundry goods machining center, includes the support frame, be provided with the base on the support frame, the collection bits groove that is used for collecting iron fillings is offered to the up end of base, the one end that collects the bits inslot axial is the discharge gate, the base all is provided with in the both sides in collection bits groove and is used for discharging the mechanism that gathers materials in the collection bits groove with iron fillings, the base is provided with in collection bits inslot and is used for following collection bits groove exhaust pushing equipment with iron fillings.

Through adopting above-mentioned technical scheme, when needing to clear up the iron fillings on the base, earlier concentrate the iron fillings on the base to an album bits inslot through the mechanism that gathers materials, release the iron fillings in the chip collection groove through pushing equipment after that to accomplish the clearance of iron fillings, improve the cleaning efficiency of iron fillings, also reduce staff's work load simultaneously.

Optionally, the mechanism of gathering materials includes album flitch and fixed pin, set up the mounting groove that supplies album flitch card to go into on the base, it is articulated with the inside wall that the mounting groove is close to the chip groove to collect the flitch, the inside wall of the adjacent articulated department of mounting groove runs through and sets up the first fixed orifices that supplies the fixed pin to pass, set up the second fixed orifices with first fixed orifices intercommunication on the flitch.

Through adopting above-mentioned technical scheme, during the clearance iron fillings, extract the fixed pin from first fixed orifices, will gather the flitch and roll out from the mounting groove after that for gather the state that the flitch formed the slope, thereby make the iron fillings on the board that gathers materials fall into the chip groove, and then reach the effect of quick clearance iron fillings.

Optionally, a positioning hole for inserting the fixing pin is formed in the inner side wall of the mounting groove on the same side as the first fixing hole in a penetrating mode, and the positioning hole is located between the chip collecting groove and the first fixing hole.

Through adopting above-mentioned technical scheme, extract the back with the fixed pin in first fixed orifices, can follow the mounting groove with the flitch that gathers materials and roll out, insert the fixed pin in the locating hole after that for the fixed pin is hugged closely with the one side of the board orientation mounting groove diapire that gathers materials, thereby makes the board that gathers materials keep the tilt state, and the people of being convenient for will gather the iron fillings on the board and clear up to the collection bits inslot.

Optionally, the aggregate plate is provided with the vibrating plate from one side of mounting groove diapire, the aggregate plate is provided with a plurality of groove of stepping down towards one side of vibrating plate, every the diapire in groove of stepping down all is provided with supporting spring, every supporting spring keeps away from the one end of stepping down the groove diapire and all connects on the vibrating plate.

Through adopting above-mentioned technical scheme, will collect the flitch and lift up and keep behind the tilt state from the mounting groove, pat the vibrations flitch with the hand interval, the vibrations flitch passes through supporting spring and produces vibrations to make on the vibrations flitch remaining iron fillings fall into the chip groove from the vibrations flitch in, improve the cleaning efficiency of iron fillings, labour saving and time saving.

Optionally, the vibration plate is provided with a limiting block towards one side of the material collecting plate, a limiting groove for the limiting block to be clamped in is formed in the material collecting plate, the limiting groove is communicated with the second fixing hole, and a limiting hole for the fixing pin to be inserted is formed in the limiting block.

Through adopting above-mentioned technical scheme, gather materials the integrated circuit board and go into the mounting groove back, press the vibrations flitch for stopper card on the vibrations flitch goes into the spacing inslot, then inserts first fixed orifices, second fixed orifices and spacing inslot with the fixed pin in proper order, thereby makes vibrations flitch and the board that gathers materials keep hugging closely the state, and the staff of being convenient for normally moves on the base.

It is optional, pushing equipment includes the scraping wings, pushes away the material motor and two push away the material lead screw, the scraping wings slides and sets up in the chip groove, the scraping wings all is provided with the sliding block towards the back of the body both sides that carry on mutually of chip groove inside wall, the two inside walls in opposite directions of chip groove all have been seted up along self length direction and have been supplied the sliding block card to go into and gliding sliding tray, two it rotates respectively and sets up in two sliding trays to push away the material lead screw, push away the material lead screw and pass the sliding block and with sliding block threaded connection, every the lateral wall that the one end that pushes away the material lead screw all stretches out and is provided with driven gear from the base, it sets up in one side of base towards driven gear to push away the material motor, it is provided with the driving gear on the output shaft of material motor to push away, the common cover is equipped with gear belt on driving gear and two driven gear, driving gear and driven gear all with gear belt intermeshing.

By adopting the technical scheme, when the scrap collecting groove needs to be cleaned, the material pushing motor is started, the driving gear drives the gear belt to rotate, the gear belt drives the two driven gears to rotate, the two driven gears drive the material pushing screw rod to rotate, the material pushing screw rod rotates to drive the sliding block to slide in the sliding groove, and therefore the scrap iron in the scrap collecting groove is pushed out from the discharge hole of the scrap collecting groove by the material pushing plate.

Optionally, a material shoveling strip used for clinging to the bottom wall of the chip collecting groove is arranged on one side, away from the material pushing motor, of the material pushing plate.

By adopting the technical scheme, on one hand, the material shoveling strip can improve the contact area between the material pushing plate and the bottom wall of the chip collecting groove, and when the material pushing plate moves in the chip collecting groove, the material shoveling strip can reduce scrap iron remaining on the bottom wall of the chip collecting groove; on the other hand, the shoveling strips can provide supporting force for the material pushing plate, so that the situation that the material pushing plate inclines is reduced, the material pushing effect is ensured, and scrap iron residues are reduced.

Optionally, a feeding mechanism for conveying iron chips is arranged below the discharge port of the chip collecting groove, the feeding mechanism comprises a feeding frame, a conveying belt for conveying the iron chips is arranged on the feeding frame, and a receiving box for receiving the iron chips is arranged at one end of the feeding frame.

Through adopting above-mentioned technical scheme, the iron fillings are directly fallen on the conveyer belt after pushing away from the discharge gate in collection bits groove by pushing equipment, and the conveyer belt carries iron fillings to receiving in the workbin, conveniently carries out subsequent processing to iron fillings.

Optionally, all be provided with around the base and be used for restricting the protection rail of iron fillings departure.

Through adopting above-mentioned technical scheme, add man-hour when the foundry goods, some iron fillings can fly out by accident, and the protection rail can block the iron fillings of flying out, ensures staff's personal safety, reduces the pollution of iron fillings to the production environment.

In summary, the present application includes at least one of the following beneficial technical effects:

1. when needing to clear up the iron fillings on the base, concentrate the iron fillings on the base to the collection bits inslot through the mechanism that gathers materials earlier, release the iron fillings in the collection bits inslot through pushing equipment after that to accomplish the clearance of iron fillings, improve the cleaning efficiency of iron fillings, also reduce staff's work load simultaneously.

2. Extract the back with the fixed pin in first fixed orifices, can follow the mounting groove with the flitch that gathers materials and roll out, insert the locating hole with the fixed pin after that for the fixed pin is hugged closely with the board that gathers materials towards one side of mounting groove diapire, thereby makes the board that gathers materials keep the tilt state, and the people of being convenient for are with the iron fillings clearance on the board that gathers materials to the collection bits inslot.

3. After the material collecting plate is lifted from the mounting groove and kept in an inclined state, the vibration plate is patted at intervals by hands and vibrates through the supporting spring, so that residual scrap iron on the vibration plate falls into a scrap collecting groove from the vibration plate, the cleaning efficiency of the scrap iron is improved, and time and labor are saved.

4. When the scrap collecting groove needs to be cleaned, the material pushing motor is started, the driving gear drives the gear belt to rotate, the gear belt drives the two driven gears to rotate, the two driven gears drive the material pushing screw to rotate, the material pushing screw rotates to drive the sliding block to slide in the sliding groove, and therefore the scrap iron in the scrap collecting groove is pushed out from the discharge hole of the scrap collecting groove by the material pushing plate.

5. On one hand, the material shoveling strip can improve the contact area between the material pushing plate and the bottom wall of the chip collecting groove, and when the material pushing plate moves in the chip collecting groove, the material shoveling strip can reduce scrap iron remaining on the bottom wall of the chip collecting groove; on the other hand, the shoveling strips can provide supporting force for the material pushing plate, so that the situation that the material pushing plate inclines is reduced, the material pushing effect is ensured, and scrap iron residues are reduced.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present application.

Fig. 2 is a partial structural schematic diagram of an embodiment of the present application.

Fig. 3 is an explosion diagram of the material collecting plate in the embodiment of the application when the material collecting plate rotates to an inclined state.

Fig. 4 is a structural schematic diagram of the seismic material plate in a bottom view in the embodiment of the present application.

Fig. 5 is a schematic structural diagram of the material collecting plate in the embodiment of the present application when the material collecting plate rotates to an inclined state.

Fig. 6 is an enlarged schematic view of the region a in fig. 5.

Description of reference numerals:

1. a support frame; 2. a base; 21. a chip collecting groove; 211. a sliding groove; 22. mounting grooves; 221. a first fixing hole; 222. positioning holes; 22. a discharge port; 3. a material collecting mechanism; 31. a material collecting plate; 311. a second fixing hole; 312. a yielding groove; 313. a limiting groove; 32. a fixing pin; 33. a material vibrating plate; 331. a limiting block; 3311. a limiting hole; 34. a support spring; 4. a material pushing mechanism; 41. a material pushing plate; 411. a slider; 42. a material pushing motor; 43. a material pushing screw rod; 44. a driven gear; 45. a driving gear; 46. a gear belt; 5. shoveling the material strips; 6. a feeding mechanism; 61. a feeding frame; 62. a conveyor belt; 63. a material receiving box; 7. and (6) protecting the fence.

Detailed Description

The present application is described in further detail below with reference to figures 1-6.

The embodiment of the application discloses a casting machining center. Referring to fig. 1 and 2, the iron scrap collecting device comprises a support frame 1 placed on the ground, a rectangular base 2 is installed on the upper end face of the support frame 1, a scrap collecting groove 21 used for collecting iron scraps is formed in the middle of the upper end face of the base 2 along the length direction of the base, a discharge hole 22 is formed in one axial end of the scrap collecting groove 21, and the discharge hole 22 is communicated with the outside. The base 2 is provided with the mechanism 3 that gathers materials that is used for discharging iron fillings into the chip groove 21 in the both sides of chip groove 21, and one side that the bin outlet was kept away from to the base 2 is provided with and is used for the pushing equipment 4 of iron fillings from chip groove 21 exhaust, and the discharge gate 22 below of chip groove 21 is provided with the feeding mechanism 6 that is used for collecting iron fillings. When iron chips on the base 2 are cleaned, the iron chips on the base 2 are firstly concentrated into the chip collecting groove 21 through the collecting mechanism 3, then the iron chips in the chip collecting groove 21 are pushed out through the pushing mechanism 4, and finally the iron chips are recovered through the feeding mechanism 6.

Referring to fig. 1, a protective fence 7 for limiting iron chips from flying out is installed around the base 2. The protective fence 7 can block flying scrap iron, so that the personal safety of workers is guaranteed.

Referring to fig. 3 and 4, the material collecting mechanism 3 includes a rectangular material collecting plate 31 and a fixing pin 32 with a circular cross section, a rectangular mounting groove 22 for the material collecting plate 31 to be clamped in is formed in the base 2, and a long edge of one side of the material collecting plate 31 is hinged to the inner side wall of the mounting groove 22 close to the material collecting groove 21. The mounting groove 22 is provided with a positioning hole 222 and a first fixing hole 221 for the fixing pin 32 to pass through along the direction away from the chip collecting groove 21 on the inner side wall away from the pushing mechanism 4, the collecting plate 31 is provided with a second fixing hole 311 communicated with the first fixing hole 221, and the inner side walls of the first fixing hole 221 and the second fixing hole 311 are tightly attached to the outer side wall of the fixing pin 32. Placing the material collecting plate 31 into the mounting groove 22, and then inserting the fixing pins 32 into the first fixing holes 221 and the second fixing holes 311 in sequence, so that the material collecting plate 31 can be fixed in the mounting groove 22, and the material collecting plate 31 is limited from being accidentally rotated out of the mounting groove 22; after the fixing pin 32 is pulled out from the first fixing hole 221, the aggregate plate 31 can be rotated out from the mounting groove 22, and then the fixing pin 32 is inserted into the positioning hole 222, so that the fixing pin 32 and the aggregate plate 31 are tightly attached to one side of the bottom wall of the mounting groove 22, the aggregate plate 31 keeps an inclined state, and scrap iron on the aggregate plate 31 can be cleaned to the scrap collecting groove 21 conveniently.

Referring to fig. 3 and 4, one side of the material collecting plate 31 departing from the bottom wall of the mounting groove 22 is provided with a rectangular vibration material plate 33, the yielding groove 312 is respectively arranged at four corners of one side of the material collecting plate 31 facing the vibration material plate 33, the bottom wall of each yielding groove 312 is fixedly connected with a supporting spring 34, and one end of each supporting spring 34, which is far away from the bottom wall of the yielding groove 312, is fixedly connected to one side of the material collecting plate 33 facing the material collecting plate 31. After the aggregate plate 31 is lifted from the mounting groove 22 and kept in an inclined state, the vibration plate 33 is patted by hand, and the vibration plate 33 vibrates through the supporting spring 34, so that the residual iron chips on the vibration plate 33 fall into the chip collecting groove 21 from the vibration plate 33, and the cleaning efficiency of the iron chips is improved.

Referring to fig. 3 and 4, the vibration plate 33 is fixedly connected with a limiting block 331 toward one side of the material collecting plate 31, a limiting groove 313 for the limiting block 331 to be clamped in is formed on the material collecting plate 31, the limiting groove 313 is communicated with the second fixing hole 311, a limiting hole 3311 for the fixing pin 32 to be inserted is formed in the limiting block 331, and the inner side wall of the limiting hole 3311 is tightly attached to the outer side wall of the fixing pin 32. After the material collecting plate 31 is clamped into the mounting groove 22, the material vibrating plate 33 is pressed, the limiting block 331 on the material vibrating plate 33 is clamped into the limiting groove 313, then the fixing pins 32 are sequentially inserted into the first fixing hole 221, the second fixing hole 311 and the limiting groove 313, the material vibrating plate 33 and the material collecting plate 31 are kept in a tightly attached state while the material collecting plate 31 is locked, the worker can conveniently move on the base 2 normally, and time and labor are saved.

Referring to fig. 5 and 6, the pushing mechanism 4 includes a rectangular pushing plate 41, a pushing motor 42, and two pushing screws 43, the pushing plate 41 is slidably disposed in the chip collecting groove 21, and the pushing plate 41 can slide along the length direction of the chip collecting groove 21. The two opposite sides of the material pushing plate 41 facing the inner side walls of the chip collecting grooves 21 are fixedly connected with sliding blocks 411, and the two opposite inner side walls of the chip collecting grooves 21 are provided with sliding grooves 211 along the length direction of the sliding blocks 411 for the sliding blocks 411 to be clamped and slide. The two material pushing screw rods 43 are respectively rotatably arranged in the two sliding grooves 211 along the length direction of the sliding grooves 211, the material pushing screw rods 43 penetrate through the sliding blocks 411 and are in threaded connection with the sliding blocks 411, one end, far away from the discharge port 22, of each material pushing screw rod 43 extends out of the outer side wall of the base 2 and is fixedly connected with a driven gear 44, and the driven gear 44 and the material pushing screw rods 43 are arranged coaxially. The pushing motor 42 is fixedly connected to one side of the base 2 far away from the discharge hole 22, and the pushing motor 42 is a servo motor capable of rotating forward and backward. The output shaft of the pushing motor 42 deviates from the base 2 and is fixedly sleeved with a driving gear 45, and the driving gear 45 and the output shaft of the pushing motor 42 are arranged coaxially. The driving gear 45 and the two driven gears 44 are sleeved with a gear belt 46 together, and the driving gear 45 and the driven gears 44 are meshed with the gear belt 46.

When the scrap collecting groove 21 needs to be cleaned, the pushing motor 42 is started, the driving gear 45 drives the gear belt 46 to rotate, the gear belt 46 drives the two driven gears 44 to rotate, the two driven gears 44 drive the pushing screw rod 43 to rotate, the pushing screw rod 43 rotates to drive the sliding block 411 to slide in the sliding groove 211, and therefore the pushing plate 41 pushes scrap iron in the scrap collecting groove 21 out of the discharge hole 22 of the scrap collecting groove 21.

Referring to fig. 5 and 6, the lower end of one side of the material pushing plate 41 facing the material outlet 22 is fixedly connected with a material shoveling strip 5, and the cross section of the material shoveling strip 5 is triangular and is tightly attached to the bottom wall of the chip collecting groove 21. The material shoveling strips 5 can reduce scrap iron remaining on the bottom wall of the scrap collecting groove 21; in addition, the shoveling strips 5 can provide supporting force for the material pushing plates 41, so that the situation that the material pushing plates 41 incline is reduced.

Referring to fig. 2, the feeding mechanism 6 includes a feeding rack 61 installed on the floor, and the feeding rack 61 is located below the discharge port 22. The upper end face of the feeding frame 61 is provided with a conveyor belt 62 used for conveying scrap iron along the length direction, a material receiving box 63 used for receiving the scrap iron is placed at one axial end of the feeding frame 61, and an opening of the material receiving box 63 faces upwards. After the ejector plate 41 pushes the iron chips out from the discharge hole 22 of the chip collecting groove 21, the iron chips directly fall on the conveyor belt 62, and the conveyor belt 62 conveys the iron chips to the material receiving box 63, so that the iron chips are conveniently recovered by the worker.

The implementation principle of the casting machining center provided by the embodiment of the application is as follows: when the scrap iron on the base 2 is cleaned, the vibration plate 33 is pressed by hand, the fixing pin 32 is pulled out from the first fixing hole 221, the material collecting plate 31 is rotated out from the mounting groove 22, the fixing pin 32 is inserted into the positioning hole 222 after the material collecting plate 31 is rotated to an inclined state, the fixing pin 32 is tightly attached to the material collecting plate 31, the material collecting plate 31 keeps the inclined state, the vibration plate 33 is flapped by hand, the scrap iron falls into the scrap collecting groove 21, the material pushing motor 42 is started to drive the material pushing plate 41 to slide, the scrap iron in the scrap collecting groove 21 is pushed out from the discharge hole 22 by the material pushing plate 41, the pushed scrap iron falls onto the conveyor belt 62, and finally the scrap iron falls into the material collecting box 63 along with the conveyor belt 62.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: equivalent changes in structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. The utility model provides a foundry goods machining center, includes support frame (1), be provided with base (2) on support frame (1), its characterized in that: the scrap collecting groove (21) used for collecting scrap iron is formed in the upper end face of the base (2), a discharge hole is formed in one axial end of the scrap collecting groove (21), the two sides of the scrap collecting groove (21) of the base (2) are respectively provided with a collecting mechanism (3) used for discharging the scrap iron into the scrap collecting groove (21), and a material pushing mechanism (4) used for discharging the scrap iron from the scrap collecting groove (21) is arranged in the scrap collecting groove (21) of the base (2);

the material collecting mechanism (3) comprises a material collecting plate (31) and fixing pins (32), a mounting groove (22) for the material collecting plate (31) to be clamped in is formed in the base (2), the material collecting plate (31) is hinged to the inner side wall, close to the material collecting groove (21), of the mounting groove (22), the inner side wall, at the position, adjacent to the hinge, of the mounting groove (22) penetrates through a first fixing hole (221) for the fixing pin (32) to penetrate through, and a second fixing hole (311) communicated with the first fixing hole (221) is formed in the material collecting plate (31);

pushing equipment (4) include scraping wings (41), push away material motor (42) and two and push away material lead screw (43), scraping wings (41) slide and set up in chip groove (21), scraping wings (41) all are provided with sliding block (411) towards the back of the body both sides of chip groove (21) inside wall, chip groove (21) two inside walls in opposite directions all have been seted up along self length direction and have been supplied sliding block (411) card to go into and gliding sliding tray (211), two it rotates respectively and sets up in two sliding tray (211) to push away material lead screw (43), push away material lead screw (43) and pass sliding block (411) and with sliding block (411) threaded connection, every it all stretches out and is provided with driven gear (44) from the lateral wall of base (2) to push away the one end of material lead screw (43), it sets up in one side of base (2) towards driven gear (44) to push away material motor (42), be provided with driving gear (45) on the output shaft of material motor (42), common cover is equipped with driving gear (45) and two driven gear (44) is equipped with gear belt (46), driving gear (45) and driven gear (44) all intermesh with driven gear (46), driving gear (44).

2. A casting machining center as defined in claim 1, wherein: the inner side wall of the mounting groove (22) and the side wall of the first fixing hole (221) are provided with positioning holes (222) for inserting the fixing pins (32), and the positioning holes (222) are located between the chip collecting grooves (21) and the first fixing hole (221).

3. A casting machining center as defined in claim 2, wherein: one side that collection flitch (31) deviate from mounting groove (22) diapire is provided with vibrating plate (33), collection flitch (31) are provided with a plurality of groove of stepping down (312) towards one side of vibrating plate (33), every the diapire in groove of stepping down (312) all is provided with supporting spring (34), every supporting spring (34) are kept away from the one end in groove of stepping down (312) diapire and all are connected on vibrating plate (33).

4. A casting machining center as defined in claim 3, wherein: the material vibrating plate (33) is provided with a limiting block (331) towards one side of the material collecting plate (31), a limiting groove (313) for the limiting block (331) to be clamped in is formed in the material collecting plate (31), the limiting groove (313) is communicated with the second fixing hole (311), and a limiting hole (3311) for the fixing pin (32) to be inserted is formed in the limiting block (331).

5. A casting machining center as defined in claim 4, wherein: and a material shoveling strip (5) used for clinging to the bottom wall of the chip collecting groove (21) is arranged on one side of the material pushing plate (41) departing from the material pushing motor (42).

6. A casting machining center according to claim 1, characterized in that: the scrap iron collecting box is characterized in that a feeding mechanism (6) used for conveying scrap iron is arranged below a discharge port of the scrap collecting groove (21), the feeding mechanism (6) comprises a feeding frame (61), a conveying belt (62) used for conveying the scrap iron is arranged on the feeding frame (61), and a material collecting box (63) used for containing the scrap iron is arranged at one end of the feeding frame (61).

7. A casting machining center as defined in claim 1, wherein: and protective fences (7) used for limiting iron chips to fly out are arranged around the base (2).