JPH11291170A - Sander - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent grinding chips from being electrified in a dust bag by giving conductive property to a cylindrical body on which a dust bag is mounted. SOLUTION: A dust bas assembly 20 mounted on the discharge tube 18 of a cover 17 consists of a cuff 21 which is capable of being connected to the discharge tube 18 and is formed by extending a plurality of frames 22, 22,... to side surfaces except the connected portion, and a bag-shaped dust bag 23. The cuff 21 is integrally-molded out of carbon-contained polypropylene. The folded back part 19a of an earth plate 19 coming into contact with a fan plate 16 inside the cover 17 is exposed at the discharge tube 18. By fitting the cuff 21 onto the discharge tube 18, it is brought into the earth plate 19, and electrical connection is made between the cuff 21 and the fan plate 16.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cylinder to which an opening of a dust bag is connected is connected to a grinding powder discharge cylinder provided in a housing, and the grinding powder can be collected in the dust bag via the cylinder. About Sanda.

[0002]

2. Description of the Related Art A sander, for example, a belt sander, is provided with a sanding belt stretched between a pair of front and rear rollers driven by a motor on the lower surface of a housing, and is rotated to enable grinding of wood or the like. By the rotation of the dust collection fan fixed to the motor shaft in the housing,
Grinding powder is suctioned from a dust collecting port formed on the lower surface of the housing, and is guided to a dust collecting path formed in the housing so that the grinding powder can be discharged from a discharge cylinder. Further, the discharge cylinder is provided with a frame inserted into the dust bag, and is connected to a cylinder connected to the opening of the dust bag, so that the discharged grinding powder can be collected.

[0003]

By the way, if the material to be ground is wood and the housing is made of synthetic resin, when the grinding powder sucked in from the dust collecting port passes through the dust collecting passage in the housing, the housing and the housing are separated. It is easy to generate static electricity due to friction. According to the charging line, for example, the housing made of nylon is charged to (+), and the grinding powder of wood is charged to (-). The (-) charges are collected by a conductor in a housing such as a dust collecting fan, while the (+) charges are collected in the dust bag together with the grinding powder. The (+) charges collected in the dust collecting fan or the like are dispersed through other conductors such as a roller or leak to a power supply, so that no problem occurs. Since the body itself is also formed of a synthetic resin such as polypropylene, there is no discharge path, and the static electricity of a high charged voltage is generated as the amount of grinding powder increases. Therefore, if a hand touches or approaches the dust bag when the worker grips the handle of the housing or the like, discharge occurs in the worker's hand, and this discharge gives the worker an uncomfortable feeling.

Accordingly, an object of the present invention is to provide a sander which suppresses charging of grinding powder collected in a dust bag and does not impair usability by discharging.

[0005]

In order to achieve the above object, according to the first aspect of the present invention, the housing including the frame is provided with conductivity while the housing is connected to the discharge cylinder. At the same time, conductive means for electrically connecting the cylindrical body to a conductor in the housing is provided. According to the second aspect of the present invention, in addition to the object of the first aspect, in order to easily impart conductivity to the cylinder at low cost, the cylinder is integrally formed of a conductive resin.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a belt sander 1,
2 is a side view as viewed from the same side, and FIG. 3 is a bottom view thereof. A motor 3 is built in the upper part of the main body housing 2 made of nylon while being parallel to the short direction, while the lower part of the main body housing 2 is Has a pair of drive rollers 4 parallel to the short side direction,
A driven roller 5 is pivotally supported in the longitudinal direction, and a helical gear 6 having a pulley 7 is provided on a gear 4b integral with the roller shaft 4a of the driving roller 4 located on the rear side (right side in FIGS. 2 and 3). A synchro belt 9 is stretched between the pulley 7 and the gear portion 8a of the dust collecting fan 8 (made of aluminum) fixed to the motor shaft 3a to rotate the motor shaft 3a via the pulley 7. To the driving roller 4. A wide band-shaped sanding belt 10 is stretched between the driving roller 4 and the driven roller 5 and is exposed on the lower surface of the main body housing 2. The belt 10 rotates in the direction of the arrow in FIG. Reference numeral 11 denotes a handle formed in the upper center of the main body housing 2 in the longitudinal direction.

A dust collection port 12 is formed in the lower part of the main body housing 2 behind the drive roller 4 in a short direction of the main body housing 2, and an introduction path 13 continuous with the dust collection port 12 is driven. The roller 4 is formed inside the main body housing 2 so as to wrap around the roller 4 and move forward. On the other hand, the motor shaft 3a
A flat plate-shaped scroll plate 14 having a dust collection path 15 orbiting around it is assembled so as to penetrate the motor shaft 3a.
The introduction path 13 communicates with the entrance 5. The dust collecting fan 8 has a blade side facing the dust collecting path 15, and a metal fan plate 16 which is mounted on the upper surface of the scroll plate 14 except for the gear portion 8 a, and the dust collecting fan 8 has a scroll plate 1.
4. Further, the scroll plate 14 and the synchro belt 9,
A cover 17 is attached so as to cover the pulley 7 and the cover 1
A discharge cylinder 18 projects from the upper part of the rear part 7 in parallel with the handle 11 and communicates with the outlet of the dust collection path 15 of the scroll plate 14. As shown in FIG. 4, the discharge cylinder 18 is provided with a metal ground plate 19 that is bent from the discharge cylinder 18 along the inner surface of the cover 17. One end of the ground plate 19 on the scroll plate 14 side is provided. Is
While being in contact with the fan plate 16, the other end on the discharge cylinder 18 side is formed in a folded portion 19 a that is folded outward from an end edge of the discharge cylinder 18 and is exposed to the outer surface.

[0008] A dust bag assembly 20 is mounted on the discharge cylinder 18. The dust bag assembly 20 can be connected (fitted) to the discharge tube 18, and the sides except for the connection portion are opened in the axial direction to open the frames 22, 22.
A cuff 21 as a cylindrical body extending in a branch shape, and a bag-shaped dust bag 23, and the opening of the dust bag 23 is inserted into the cylinder of the cuff 21 with the frame 22 inserted into the dust bag 23. 1, the dust bag 23 can be extended into the cuff 21 and its frame 2 as shown in FIG.
The shape is maintained by 2, 22,. Also, cuffs 2
Reference numeral 1 denotes an earth plate 19 formed integrally with a conductive resin (here, polypropylene containing carbon) and imparted with conductivity. When connected to the discharge tube 18, the connection portion is exposed to the outside of the discharge tube 18. The cuff 21 is electrically connected to the fan plate 16.

The belt sander 1 configured as described above is
When the motor 3 is driven, the drive roller 4 rotates via the synchro belt 9, and the sanding belt 10 is rotated between the driven roller 5 and the driven roller 5 to grind the workpiece. At the same time, the dust collecting fan 8 rotates, sucks the grinding powder from the dust collecting port 12, guides it to the scroll plate 14 through the introduction path 13, further sends it out from the dust collecting path 15 to the discharge cylinder 18, and connects through the cuff 21. The grinding powder is discharged into the dust bag 23 to be cleaned. At this time, if the material to be ground is a material such as wood that is easily charged to (−), the grinding powder is charged to (−) by friction with the nylon main body housing 2 when passing through the introduction path 13. At the same time, the main body housing 2, the dust collecting fan 8, the fan plate 16 and the like generate static electricity charged to (+). However, the (+) charges of the main body housing 2 and the dust collecting fan 8 and the like are dispersed through the synchro belt 9 and the driving roller 4 and leak to the power supply.
On the other hand, in the grinding powder, the cuff 21 having conductivity as described above comes into contact with the ground plate 19 on the outer surface of the discharge cylinder 18 and is electrically connected to the fan plate 16. Grinding powder is cuff 2
1 and its frames 22, 22,..., The (−) charges are dropped from the cuffs 21 to the (+) charged fan plate 16 and the dust collection fan 8 via the earth plate 19. Then, the charges of (+) and (-) are combined and disappear (neutralization), or are leaked to the power supply via the synchro belt 9 and the driving roller 4 as described above.

As described above, according to the above-described embodiment, the cuff 21 connecting the dust bag 23 is electrically connected to the conductor such as the fan plate 16 on the cover 17 side by providing conductivity. The static electricity generated in the grinding powder is neutralized or leaked to the power supply, and the charging of the grinding powder in a state of being collected in the dust bag 23 can be effectively prevented. Therefore, the hand holding the handle 11 by the worker holds the dust bag 2
Even if the user touches or approaches 3, no discharge occurs due to static electricity and the usability is not impaired. Also, frame 22
At the same time, the cuff 21 is integrally formed of a conductive resin, so that conductivity can be imparted to the cuff 21 at low cost while keeping the weight low. In addition, the cuff 21 is obtained as a single part, so that the assembling is simplified.

The purpose of the present invention is to provide conductivity to the cylindrical body to which the dust bag 23 is connected.
May be formed as an integral product made of a metal, for example, a lightweight metal such as aluminum die-cast, or a conductive portion may be formed on the inner surface of a non-conductive cylinder by plating or the like. Further, the shape of the cuffs 21 is not limited to the above-described embodiment, and the design including the number and the shape of the frames 22 can be appropriately changed as long as the dust bags 23 can be connected and connected to the belt sander 1. . Further, in the above-described embodiment, the conduction means to the dust bag assembly 20 and the fan plate 16 is realized by the ground plate 19. In this case, the electrical connection between the two becomes possible with only one part of the earth plate 19,
Although desirable in terms of cost, etc., this configuration can also be changed as appropriate,
A metal sleeve provided with a flange portion or a folded portion which is engaged with an end edge of the discharge tube 18 is fitted into the discharge tube 18, or the cover 17 or the discharge tube 18 is formed of a conductive resin like a cuff 21. The conductive means is not limited as long as it is electrically connected to the internal conductor at the same time when the cuff 21 is mounted, such as when the cuff 21 is mounted.

[0012]

According to the first aspect of the present invention, since the cylindrical body on which the dust bag is mounted is provided with conductivity and is electrically connected to the conductor in the main body housing by the conducting means, Static electricity generated in the grinding powder during dust collection is neutralized or leaked to the power supply, and the charging of the grinding powder in a state of being collected in the dust bag can be effectively prevented.
Therefore, even if the worker's hand holding the handle touches or approaches the dust bag, no electrostatic discharge occurs,
It does not impair usability. According to the second aspect of the present invention, in addition to the effect of the first aspect, since the cylindrical body is integrally formed with the conductive resin, the conductivity can be imparted to the cylindrical body at a low cost at a low cost. Further, the cylindrical body including the frame can be obtained by one part, and the assembling becomes simple.

[Brief description of the drawings]

FIG. 1 is a perspective view of a belt sander.

FIG. 2 is a side view of a belt sander.

FIG. 3 is a bottom view of the belt sander.

FIG. 4 is an explanatory diagram showing a connection state between a discharge cylinder and a dust bag assembly.

[Explanation of symbols]

1. Belt sander, 2. Body housing, 3. Motor, 8. Dust collecting fan, 10. Sanding belt, 11. Handle, 12. Dust collection port, 13. Introduction path, 14.・ Scroll plate, 16 ・ ・ Fan plate, 18 ・ ・ Eject cylinder, 19 ・ ・ Earth plate, 20
..Dust bag assembly, 21. Cufflinks, 22
..Frame, 23..Dust bag.

Claims (2)

[Claims] 1. A grinding machine which is provided with a frame inserted into a dust bag and which has an opening of the dust bag connected thereto, is connected to a grinding powder discharge cylinder provided in a housing, and the grinding powder is discharged from the housing. A sander capable of collecting powder into a dust bag through the cylindrical body, while imparting conductivity to the cylindrical body including the frame, and connecting the housing to the discharge cylinder while simultaneously connecting the cylindrical body to the discharge cylinder. A sander provided with conducting means for electrically connecting to a conductor in the housing. 2. The sander according to claim 1, wherein the cylindrical body is integrally formed of a conductive resin.