CN112873426A

CN112873426A - Wood cutting system and method

Info

Publication number: CN112873426A
Application number: CN202110051345.XA
Authority: CN
Inventors: 陈祥
Original assignee: Individual
Current assignee: Yangxin Eurasia Woodenware Co ltd
Priority date: 2019-04-24
Filing date: 2019-04-24
Publication date: 2021-06-01
Anticipated expiration: 2039-04-24
Also published as: CN112873426B; CN110039607B; CN110039607A

Abstract

The invention discloses a wood cutting system and a wood cutting method. The invention drives the rotating wheel and the brush head with positive electricity through the driving shaft, so that sawdust adhered to the inner surface of the saw blade is centrifugally thrown out along the tangential direction under the scraping inertia force of the brush head, wet sawdust is prevented from being adhered to the inner side surface of the saw blade and then accumulated on the contact surface of the saw blade and the rotating wheel, the saw blade runs out and is easy to stretch off, meanwhile, under the action of the generator and the conductive rod, the upper rotating plate and the lower rotating plate are alternately provided with negative electricity, the positively charged sawdust blown by the air gun is attracted and concentrated, then, a low-temperature environment is formed by the cooling cavity and the circulating cavity, the saw blade which passes through is cooled, the high-temperature stretching off is prevented, and meanwhile, the static electricity on the saw blade is removed through the static electricity removal pad, and the lower saw wheel is prevented from.

Description

Wood cutting system and method

The invention relates to a divisional application of wood cutting equipment for removing scraps and preventing strip running by utilizing inertia static electricity, and the invention has an application date of 2019, 4 and 24 and an application number of CN201910335995.

Technical Field

The invention relates to the field of wood processing, in particular to a wood cutting system and a wood cutting method.

Background

Along with the improvement of mechanical automation and standard of living, the use of panel is increasing day by day, and the panel is obtained through processing again through band saw machine cutting log, and the saw-dust that produces when cutting is concentrated through fan suction at present and is got rid of, and current traditional art considers not comprehensively, has following drawback:

log pine is easily dampened, its outside round moisture that absorbs water behind the durable, and pine itself contains comparatively abundant grease, the saw-dust that the cutting produced is moist, the oil moistens and has stronger adhesion, only depend on the suction of fan saw-dust on can't the complete clearance saw-dust, make moist saw-dust constantly pile up in the clearance face that the saw-dust inboard contacted with lower saw wheel, not only make saw-dust and saw wheel clearance increase cause the strip of running, and make the saw-dust constantly tighten, lead to the saw-dust to vibrate the emergence rupture easily in sawing.

Disclosure of Invention

Aiming at the defects of the prior art, the invention aims to provide a wood cutting system and a wood cutting method, so as to solve the problems that the log pine in the prior art is easy to damp, a circle of the outside of the log pine absorbs water and is moist after being used for a long time, the pine wood contains abundant grease, the wood chips generated by cutting are moist and oily and have strong adhesion, the wood chips on the saw blade cannot be completely cleaned only by the suction of a fan, the moist wood chips are continuously accumulated on the clearance surface of the inner side of the saw blade, which is contacted with a lower saw wheel, the gap between the saw blade and the saw wheel is increased, the strips are run, the saw blade is continuously tightened, and the saw blade is easy to vibrate and break during the sawing.

In order to achieve the purpose, the invention is realized by the following technical scheme:

the utility model provides a timber cutting system and method, its structure includes saw wheel case, reduces the hand wheel, removes and leans on mountain plate, saw blade, workstation, suction to remove bits pipe, service brake board, prevents running strip device, frame, the right-hand member face of going up the saw wheel case has inlayed and has reduced the hand wheel and be connected through the pivoted mode, remove and lean on the mountain plate to locate the upper surface of workstation and through the mode sliding connection of laminating, the saw blade embedding is installed in the below of last saw wheel case and runs through the workstation, the suction is removed the below of bits pipe and is equipped with the service brake board, the right-hand member face of preventing running strip device has inlayed the service brake board and is through nested mode sliding connection, go up the saw wheel case and be connected with preventing running strip device through the frame, suction removes the embedding of bits pipe and installs in the right-hand member face of preventing running strip device, prevent running strip device includes upper shed, outer housing, transmission band pulley, fixed rotating shaft, connecting, Saw wheel, chip removing mechanism, cooling mechanism, air gun down, the saw blade passes the upper shed and rotates with saw wheel down through the mode of laminating to be connected, the upper shed has been inlayed to the upper surface of dustcoat, the transmission band wheel is connected with saw wheel down through fixed rotating shaft, the below that removes chip mechanism is equipped with cooling mechanism, the inside in the dustcoat is installed in the embedding of cooling mechanism, air gun has been inlayed in the left side that removes chip mechanism.

As a further scheme of the invention, the scrap removing mechanism is provided with a driving shaft, an inertial centrifugal brush and a scrap storage wheel, the driving shaft and the inertial centrifugal brush are rotatably connected in a nesting mode, and the driving shaft is embedded and installed in the scrap storage wheel.

As a further scheme of the invention, the cooling mechanism is provided with a cooling cavity, a support, a circulating pipe, a circulating cavity and a static elimination pad, the cooling cavity is communicated with the circulating cavity through the circulating pipe, the cooling cavity is embedded in the support, and the static elimination pad is embedded in the support and attached to a saw blade.

As a further scheme of the invention, the inertial centrifugal brush is provided with a rotating wheel, a partition plate, a conducting ring and a brush head, wherein the partition plate is embedded in the rotating wheel, the conducting ring is connected with the brush head, and a driving shaft is embedded in the rotating wheel.

As a further scheme of the invention, the scrap storage wheel is provided with an insulating housing, a scrap inlet, a generator, a conducting rod, an upper rotating plate and a lower rotating plate, the generator is arranged on the inner wall of the insulating housing and connected in an adhesion manner, the generator is connected with the conducting rod, the conducting rod is embedded and mounted on the inner wall of the insulating housing, the upper rotating plate and the lower rotating plate are fixedly mounted on the outer surface of the driving shaft, the scrap inlet is embedded in the left end face of the insulating housing, and the conducting rod is in sliding connection with the right end face of the upper rotating plate in an adhesion manner.

As a further scheme of the invention, the upper rotating plate and the lower rotating plate are symmetrically distributed on the outer side of the driving shaft in half, and an insulating boundary line is arranged between the upper rotating plate and the lower rotating plate.

As a further scheme of the invention, the conducting rod is fixedly arranged inside the insulating cover shell and is not contacted with the upper rotating plate and the lower rotating plate simultaneously.

In a further embodiment of the present invention, the surface of the static elimination pad contacting with the saw blade is arc-shaped, which helps to diffuse charges and remove static rapidly.

As a further scheme of the invention, the cooling mechanism is of a cylindrical structure, a round through hole is embedded in the cooling mechanism, the diameter of the round through hole is larger than the width of the saw blade, and the saw blade penetrates through the through hole to cool.

Advantageous effects of the invention

Compared with the prior art, the invention drives the lower saw wheel to rotate around the fixed rotating shaft through the transmission belt wheel and enables the saw blade to move rapidly to cut pine wood through the mutual matching of the upper saw wheel box, the saw blade stuck with saw dust moves downwards through the upper opening during cutting, the driving shaft drives the rotating wheel and the brush head to rotate, the brush head is provided with positive electricity through the conductive action of the conductive ring, the brush head and the saw blade move relatively, so that the saw dust on the inner side surface of the saw blade is thrown out by inertia along the tangential direction of the rotation of the brush head under the stress of the air jet gun, centrifugal motion is generated, moist saw dust is prevented from being adhered to the inner side surface of the saw blade and then accumulated on the contact surface of the saw blade and the rotating wheel to cause the saw blade to run out, then the saw dust flies to the chip inlet of the insulating housing under the air jet pushing action of the air jet gun, meanwhile, the upper rotating plate and the, concentrate, then utilize the inside coolant liquid of circulating pipe and circulation chamber circulation flow cooling chamber, form low temperature environment, cool down the saw blade that passes, prevent that the saw blade high temperature from straining absolutely, simultaneously through the electric charge that destatic pad conduction saw blade has, detach the static on the saw blade, prevent down the saw wheel damage.

Compare in traditional wood cutting equipment, this wood cutting equipment passes through the driving shaft and drives the runner and have the brush head rotation of positive electricity through the conducting ring, make the adhesion in the saw-dust of saw blade internal surface throw away along its tangential direction centrifugation under receiving the strike off inertial force of brush head, prevent moist saw-dust adhesion in the saw blade inboard surface, pile up in saw blade and runner contact surface after, cause the saw blade to run the strip, easily stretch out, then fly to the right side under the promotion of air gun, go up the rotor plate and the crisscross negative electricity that has of rotor plate down under the effect of generator and conducting rod simultaneously, attract the saw-dust of the positive electricity that is blown by the air gun, concentrate, then utilize cooling chamber and circulation chamber to form low temperature environment, cool down the saw blade that passes, prevent its high temperature from stretching out, simultaneously through removing static pad conduction electric charge, detach the static on the saw blade, prevent that the lower saw wheel from damaging.

Drawings

Other features, objects and advantages of the invention will become more apparent from a reading of the detailed description of non-limiting embodiments with reference to the attached drawings.

In the drawings:

fig. 1 is a schematic structural diagram of a wood cutting system and method according to the present invention.

Fig. 2 is a plan view showing a front structure of a runner block according to the present invention.

FIG. 3 is a plan view showing a side view of an anti-runner apparatus according to the present invention.

Fig. 4 is an explanatory view showing components of a chip removing mechanism in the anti-running strip device according to the present invention.

Fig. 5 is a schematic diagram illustrating a component analysis of a cooling mechanism in the anti-slide device according to the present invention.

FIG. 6 is an explanatory view of the components of the inertial centrifugal brush in the chip removing mechanism according to the present invention.

FIG. 7 is a schematic diagram illustrating an exploded view of a chip storage wheel of a chip removing mechanism according to the present invention.

In the figure: an upper saw wheel box-1, a tightening hand wheel-2, a movable backer board-3, a saw blade-4, a workbench-5, a suction scrap removal pipe-6, a foot brake board-7, a strip running prevention device-8, a machine base-9, an upper opening-81, an outer casing-82, a transmission pulley-83, a fixed rotating shaft-84, a connecting piece-85, a lower saw wheel-86, a scrap removal mechanism-87, a cooling mechanism-88, an air gun-89, a driving shaft-871, an inertial centrifugal brush-872, a scrap storage wheel-873, a cooling cavity-881, a support-882, a circulating pipe-883, a circulating cavity-884, an antistatic pad-885, a rotating wheel-8721, a partition-8722, a conductive ring-8723, a brush head-8724, an insulating casing-8731, a dust removal pipe-86, A chip inlet-8732, a generator-8733, a conducting rod-8734, an upper rotating plate-8735 and a lower rotating plate-8736.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

As shown in fig. 1-7, the present invention provides a technical solution of a wood cutting system and method:

as shown in fig. 1-3, a wood cutting system and method, the structure of which comprises an upper saw wheel box 1, a reducing hand wheel 2, a movable backer 3, a saw blade 4, a workbench 5, a suction chip removal tube 6, a foot brake plate 7, a chip removal device 8 and a machine base 9, wherein the reducing hand wheel 2 is embedded in the right end face of the upper saw wheel box 1 and is connected in a rotating manner, the movable backer 3 is arranged on the upper surface of the workbench 5 and is connected in a sliding manner in a fitting manner, the saw blade 4 is embedded in and arranged below the upper saw wheel box 1 and penetrates through the workbench 5, the foot brake plate 7 is arranged below the chip removal tube 6, the foot brake plate 7 is embedded in the right end face of the chip removal device 8 and is connected in a sliding manner in a nesting manner, the upper saw wheel box 1 is connected with the chip removal device 8 through the machine base 9, the suction chip removal tube 6 is embedded in and arranged on the right end face of the chip removal device 8, prevent running strip device 8 and include upper shed 81, dustcoat 82, transmission band pulley 83, fixed rotating shaft 84, connecting piece 85, saw wheel 86 down, remove bits mechanism 87, cooling mechanism 88, air gun 89, saw blade 4 passes upper shed 81 and is connected with saw wheel 86 down through the mode rotation of laminating, the upper shed 81 has been inlayed to the upper surface of dustcoat 82, transmission band pulley 83 is connected with saw wheel 86 down through fixed rotating shaft 84, it is equipped with cooling mechanism 88 to remove the below of bits mechanism 87, cooling mechanism 88 embedding is installed in the inside of dustcoat 82, air gun 89 has been inlayed in the left side that removes bits mechanism 87.

As shown in fig. 4, the scrap removing mechanism 87 is provided with a driving shaft 871, an inertial centrifugal brush 872 and a scrap storage wheel 873, the driving shaft 871 is rotatably connected with the inertial centrifugal brush 872 in a nested manner, the driving shaft 871 is embedded in the scrap storage wheel 873, and scrap removal is performed by the mutual matching of the above structures.

As shown in fig. 5, the cooling mechanism 88 is provided with a cooling cavity 881, a support 882, a circulation pipe 883, a circulation cavity 884 and a static elimination pad 885, the cooling cavity 881 is communicated with the circulation pipe 884 through the circulation pipe 883, the cooling cavity 881 is embedded in the support 882, the static elimination pad 885 is embedded in the support 882 and is attached to the saw blade 4, the cooling cavity 881 and the circulation cavity 884 are connected for circulation to cool the saw blade 4, and then the static elimination is performed by conducting charges on the saw blade 4 through the static elimination pad 885.

As shown in fig. 6, the inertial centrifugal brush 872 is provided with a rotating wheel 8721, a partition 8722, a conductive ring 8723 and a brush head 8724, the partition 8722 is embedded in the rotating wheel 8721, the conductive ring 8723 is connected with the brush head 8724, a driving shaft 871 is embedded in the rotating wheel 8721, and the wet sawdust centrifuged under inertial force is positively charged by the rotating conductive ring 8723 and the brush head 8724.

As shown in fig. 7, the chip storage wheel 873 is provided with an insulating housing 8731, a chip inlet 8732, a generator 8733, a conductive rod 8734, an upper rotating plate 8735, and a lower rotating plate 8736, the inner wall of the insulating housing 8731 is provided with the generator 8733 and is connected with the conductive rod 8734 by adhesion, the conductive rod 8734 is embedded in the inner wall of the insulating housing 8731, the upper rotating plate 8735 and the lower rotating plate 8736 are fixedly mounted on the outer surface of the driving shaft 871, the chip inlet 8732 is embedded in the left end surface of the insulating housing 8731, the conductive rod 8734 and the right end surface of the upper rotating plate 8735 are slidably connected by adhesion, the upper rotating plate 8735 and the lower rotating plate 8736 are spaced from each other by the conductive rod 8734 to be charged with negative electricity, and the positively charged wood chips blown by the air jet gun 89 are attracted.

As shown in fig. 7, the upper rotating plate 8735 and the lower rotating plate 8736 are symmetrically distributed on the outer side of the driving shaft 871 in half, and an insulating boundary line is arranged between the upper rotating plate 8735 and the lower rotating plate 8736 to ensure that the upper rotating plate 8735 and the lower rotating plate 8736 are not electrified at the same time.

The specific realization principle is as follows: the transmission belt wheel 83 drives the lower saw wheel 86 to rotate around the fixed rotating shaft 84 and mutually match the upper saw wheel box 1 to enable the saw blade 4 to move rapidly to cut pine, the saw blade 4 adhered with saw dust moves downwards through the upper opening 81 during cutting, meanwhile, the driving shaft 871 drives the rotating wheel 8721 and the brush head 8724 to rotate, the brush head 8724 is positively charged through the electric conduction function of the conductive ring 8723, the brush head 8724 and the saw blade 4 move relatively, so that the saw dust on the inner side surface of the saw blade 4 is thrown out by inertia along the tangential direction of the rotation of the brush head 8724 to generate centrifugal motion, the moist saw dust is prevented from adhering to the inner side surface of the saw blade 4 and then accumulating on the contact surface of the saw blade 4 and the rotating wheel 8721 to cause the saw blade 4 to run out, then the saw blade flies to the chip inlet 8732 of the insulating housing 8731 under the air injection pushing action of the air injection gun 89, and the generator 8733 and the conductive rod 8734 enable the upper rotating, the saw dust with positive electricity blown by the air gun 89 is attracted and concentrated, then the circulating pipe 883 and the circulating cavity 884 are utilized to circularly flow the cooling liquid in the cooling cavity 881 to form a low-temperature environment to cool the passing saw blade 4, so as to prevent the saw blade 4 from being broken due to high temperature, and meanwhile, the static electricity on the saw blade 4 is removed by conducting the electric charge on the saw blade 4 through the static electricity removing pad 885, so that the damage of the lower saw wheel 86 is prevented.

The invention solves the problems that the log pine wood in the prior art is easy to be wet, the outer side of the log pine wood absorbs water and is moist after being used for a long time, the pine wood contains abundant grease, the saw dust generated by cutting is moist and oily and has strong adhesion, the saw dust on the saw blade cannot be completely cleaned only by the suction of a fan, so that the moist saw dust is continuously accumulated on the clearance surface of the inner side of the saw blade, which is contacted with a lower saw wheel, the clearance between the saw blade and the saw wheel is increased to cause strip running, and the saw blade is continuously tightened to cause the saw blade to be easy to vibrate and break in the sawing process, through the mutual combination of the components, the rotating wheel 8721 is driven by the driving shaft 871 and the brush head 8724 with positive electricity through the conducting ring 8723 to rotate, so that the saw dust adhered to the inner surface of the saw blade 4 is centrifugally thrown out along the tangential direction under the scraping inertia force of the brush head 8724, and, pile up in saw blade 4 and runner 8721 contact surface afterwards, cause saw blade 4 to run the strip, easily stretch out and break, then fly to the right side under the promotion of air gun 89, go up the crisscross burden charge that has of upper mounting plate 8735 and lower mounting plate 8736 under generator 8733 and conducting rod 8734's effect simultaneously, attract the saw-dust of being blown by air gun 89 and positively charged, concentrate, then utilize cooling chamber 881 and circulation chamber 884 to form low temperature environment, cool down the saw blade 4 that passes, prevent its high temperature stretch out and break, simultaneously through destatic pad 885 conduction charge, detach the static on the saw blade 4, prevent down saw wheel 86 damage.

While there have been shown and described what are at present considered the fundamental principles and essential features of the invention and its advantages, it will be apparent to those skilled in the art that the invention is not limited to the details of the foregoing exemplary embodiments, but is capable of other specific forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. The utility model provides an utilize inertia static to remove bits and prevent running wood cutting equipment of strip, its structure includes saw wheel case (1), reduces hand wheel (2), removes by mountain plate (3), saw blade (4), workstation (5), suction and removes bits pipe (6), service brake board (7), prevents running strip device (8), frame (9), its characterized in that: the upper saw wheel box is characterized in that a tightening hand wheel (2) is embedded in the right end face of the upper saw wheel box (1) and connected in a rotating mode, a movable backer board (3) is arranged on the upper surface of a workbench (5) and is in sliding connection in a fitting mode, a saw blade (4) is embedded and mounted below the upper saw wheel box (1) and penetrates through the workbench (5), a foot brake board (7) is arranged below a suction chip removal pipe (6), the foot brake board (7) is embedded in the right end face of a chip removal prevention device (8) and is in sliding connection in a nesting mode, the upper saw wheel box (1) is connected with the chip removal prevention device (8) through a machine base (9), and the suction chip removal pipe (6) is embedded and mounted on the right end face of the chip removal device (8);

the anti-strip-running device (8) comprises an upper opening (81), an outer housing (82), a transmission belt wheel (83), a fixed rotating shaft (84), a connecting piece (85), a lower saw wheel (86), a scrap removing mechanism (87), a cooling mechanism (88) and an air gun (89), wherein a saw blade (4) penetrates through the upper opening (81) and is rotatably connected with the lower saw wheel (86) in a laminating mode, the upper surface of the outer housing (82) is embedded with the upper opening (81), the transmission belt wheel (83) is connected with the lower saw wheel (86) through the fixed rotating shaft (84), the cooling mechanism (88) is arranged below the scrap removing mechanism (87), the cooling mechanism (88) is embedded in the outer housing (82), and the air gun (89) is embedded on the left side of the scrap removing mechanism (87);

the scrap removing mechanism (87) is provided with a driving shaft (871), an inertial centrifugal brush (872) and a scrap storage wheel (873), the driving shaft (871) is rotatably connected with the inertial centrifugal brush (872) in a nested mode, and the driving shaft (871) is embedded in the scrap storage wheel (873).

2. The wood cutting apparatus using inertial electrostatic chip removing catcher as claimed in claim 1, wherein: cooling mechanism (88) are equipped with cooling chamber (881), support (882), circulating pipe (883), circulation chamber (884), destatic pad (885), cooling chamber (881) switches on through circulating pipe (883) and circulation chamber (884) mutually, the inside in support (882) is installed in the embedding of cooling chamber (881), the inside of support (882) is inlayed and is destatic pad (885) and laminate mutually with saw blade (4).

3. The wood cutting apparatus using inertial electrostatic chip removing catcher as claimed in claim 1, wherein: inertia centrifugal brush (872) are equipped with runner (8721), baffle (8722), conducting ring (8723), brush head (8724), baffle (8722) have been inlayed to the inside of runner (8721), conducting ring (8723) are connected with brush head (8724), driving shaft (871) have been inlayed to the inside of runner (8721).

4. The wood cutting apparatus using inertial electrostatic chip removing catcher as claimed in claim 1, wherein: the chip storage wheel (873) is provided with an insulating housing (8731), a chip inlet (8732), a generator (8733), a conductive rod (8734), an upper rotating plate (8735) and a lower rotating plate (8736), the inner wall of the insulating housing (8731) is provided with the generator (8733) and is connected in a bonding mode, the generator (8733) is connected with the conductive rod (8734), the conductive rod (8734) is embedded in the inner wall of the insulating housing (8731), the upper rotating plate (8735) and the lower rotating plate (8736) are fixedly installed on the outer surface of a driving shaft (871), the chip inlet (8732) is embedded in the left end face of the insulating housing (8731), and the conductive rod (8734) is in sliding connection with the right end face of the upper rotating plate (8735) in a bonding mode.

5. The wood cutting apparatus using inertial electrostatic chip removing catcher as claimed in claim 4, wherein: the upper rotating plate (8735) and the lower rotating plate (8736) are symmetrically distributed on the outer side of the driving shaft (871) in a half-to-half mode, and an insulating boundary line is arranged between the upper rotating plate (8735) and the lower rotating plate (8736).

6. A wood cutting system and method according to any one of claims 1-5, wherein:

the transmission belt wheel (83) drives the lower saw wheel (86) to rotate around the fixed rotating shaft (84) and is matched with the upper saw wheel box (1) to enable the saw blade (4) to move rapidly to cut loose wood, the saw blade (4) adhered with wood chips passes through the upper opening (81) to move downwards during cutting, meanwhile, the driving shaft (871) drives the rotating wheel (8721) and the brush head (8724) to rotate, the brush head (8724) is positively charged through the conductive effect of the conductive ring (8723), the brush head (8724) and the saw blade (4) move relatively, stress on the inner side surface of the saw blade (4) is subjected to inertial throwing along the tangential direction of the rotation of the brush head (8724), centrifugal movement is generated, the wood chips are prevented from being adhered to the inner side surface of the saw blade (4) in a moist mode and then are accumulated on the contact surface of the saw blade (4) and the rotating wheel (8721), and the saw;

then, the saw blade flies to a chip inlet (8732) of an insulating housing (8731) under the air injection pushing action of an air injection gun (89), the generator (8733) and the conducting rod (8734) are used for enabling an upper rotating plate (8735) and a lower rotating plate (8736) to alternately carry negative electricity on the saw blade (4), the saw blade blown by the air injection gun (89) and positively charged is attracted and concentrated, then a circulating pipe (883) and a circulating cavity (884) are used for circularly flowing cooling liquid in a cooling cavity (881) to form a low-temperature environment, the passing saw blade (4) is cooled, the saw blade (4) is prevented from being broken due to high temperature, and meanwhile, the static electricity on the saw blade (4) is removed through a static removing pad (885), and the lower saw wheel (86) is prevented from being damaged.