JP2018065349A - Slide material for electric tool and electric tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slide material for electric tool which is excellent in slipperiness to a material to be worked and prevents occurrence of static electricity to a plastic material to be worked, and to provide an electric tool having the same, and to easily re-adhere the slide material when the slide material is degraded by handling.SOLUTION: In an electric tool 1 having a base 5, a slide material 6 is provided so as to be re-adhered to a bottom surface 5b of the base 5 via a double-sided tape and slides with a material to be worked and is formed of a resin sheet having conductivity, and the resin sheet is a sheet formed of a resin composition obtained by blending carbon black being a conductivity blending agent with a base resin such as an ultra-high-molecular-weight polyethylene resin.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sliding material to be attached to a base in an electric tool including a base such as an electric circular saw, a grid board, a router, or a jigsaw. Moreover, it is related with the electric tool provided with this sliding material.

  Conventionally, an electric tool such as an electric circular saw has been widely used when processing wood. Such an electric tool has a base, and the base cuts with a saw blade while sliding with a workpiece (a counterpart material). A conventional example of a power tool will be described with reference to FIG. FIG. 3 is a partial cross-sectional view showing an example of a conventional electric tool (portable circular saw). As shown in FIG. 3, the portable circular saw 11 includes a saw blade 12, an electric motor 13, a housing 14 containing the electric motor 13, a saw cover 16 provided so as to partially cover the saw blade 12, a saw And a base 15 having an opening on the lower surface through which the blade 12 protrudes. The saw blade 12 is rotationally driven by an electric motor 13 via a gear or the like. The base 15 is fixed to the housing 14 and the saw cover 16. The base 15 is made of, for example, aluminum die cast, magnesium die cast, iron plate, hard plastic plate, or the like. Further, the surface of the base 15 on the workpiece side is a plated surface or an untreated material surface. The portable circular saw 11 having this configuration moves the circular saw in the cutting direction while pressing the base 15 against the workpiece, and cuts the workpiece with the saw blade 12. In this way, the base 15 (sliding surface) of the base 15 slides in close contact with the workpiece during operation.

In the portable circular saw having such a configuration, there is a risk that the bottom surface of the base and the workpiece are rubbed and the workpiece is damaged. In particular, in the case of a material to be cut that attaches importance to the surface state of a decorative board or the like, there is a risk of becoming a fatal defect.
In addition, when the work material is a material that generates dust like gypsum board, this dust is interposed between the bottom surface of the base and the work material, and the work material may be damaged similarly to the above, There is a risk that the slidability of the base will decrease. In view of such a point, for example, those shown in Patent Documents 1 to 3 below have been proposed as electric tools with improved slidability of the base.

(1) Patent Document 1: Electric power tool in which a sliding contact sheet made of ultrahigh molecular polyethylene, ultra high density polyethylene, and high density polyethylene synthetic resin having wear resistance and low friction properties is installed on the bottom surface of the base. .
(2) Patent Document 2: An electric tool having a base bottom coated with a resin containing fluorine.
(3) Patent Document 3: A plate having a sliding contact surface (for example, a fluororesin plate) having a sliding resistance smaller than that of the base is attached, and the front end surface and the sliding contact surface in the cutting direction of the plate are inclined or curved. A power tool with a connected shape.

JP 2001-315075 A JP 2006-026886 A JP 2006-289869 A

  However, the conventional sliding contact sheet, resin coating, plate, and the like provided on the base surface are all made of synthetic resin and easily generate static electricity. For example, when processing plastic workpieces (plastic decorative board, plywood with plastic decorative paper, plastic board, corrugated board, etc.), processing scraps adhere to the sliding sheet on the base surface due to static electricity. There was a problem that was hindering work. In particular, there was a problem that the processing waste adhered by static electricity damaged the surface of the decorative board.

  The present invention has been made to cope with such a problem, and is excellent in slipperiness with respect to a workpiece, and for an electric tool capable of preventing generation of static electricity with respect to a plastic workpiece. An object of the present invention is to provide a sliding material and an electric tool including the same. Another object of the present invention is to enable easy replacement of the sliding material when the sliding material is deteriorated by handling.

  The sliding material for an electric tool of the present invention is a sliding material that is provided on the bottom surface of the electric tool provided with a base and slides on the workpiece. The sliding material is made of a conductive resin sheet. It is characterized by becoming.

  The resin sheet is a sheet of a resin composition containing a conductive compounding agent. The conductive compounding agent is carbon black.

  The resin sheet is a sheet of a resin composition having an ultrahigh molecular weight polyethylene (UHMWPE) resin as a base resin. The resin sheet has a thickness of 0.2 mm to 0.8 mm.

  The sliding material for an electric power tool has a double-sided tape adhered to one surface of the resin sheet, and is adhered to the base via the double-sided tape.

  The power tool of the present invention is a power tool provided with a base, wherein a sliding material is provided on the bottom surface of the base, and the sliding material is the sliding material for the power tool of the present invention. .

  In the electric power tool of the present invention, the sliding material is bonded to the base via a double-sided tape and can be replaced.

  The sliding material for an electric power tool of the present invention is a sliding material that is provided on the bottom surface of the electric tool including the base and slides on the workpiece, and is made of a conductive resin sheet. By applying the material to the electric tool, it is possible to prevent the generation of static electricity on the plastic workpiece, and the processing waste does not adhere to the bottom surface of the base, so that the work is not hindered. Moreover, the problem that a processing waste damages the decorative board surface does not arise. Furthermore, since the sliding resistance is smaller than that of the base itself, it is excellent in slipperiness with respect to the work material, and the operation feeling of the electric tool is excellent.

  Since the said resin sheet is a sheet | seat of the resin composition containing an electroconductive compounding agent, generation | occurrence | production of static electricity can be prevented effectively. In particular, by using carbon black as the conductive compounding agent, conductivity can be imparted without deteriorating slip characteristics.

  Since the said resin sheet is a sheet | seat of the resin composition which uses UHMWPE resin as a base resin, it is excellent in the abrasion-proof characteristic with respect to a process waste.

  Since the thickness of the resin sheet is 0.2 mm to 0.8 mm, it has excellent tear resistance and can be prevented from peeling from the base.

  The power tool of the present invention is a power tool provided with a base, and a slip material is provided on the bottom surface of the base, and the slip material is made of a conductive resin sheet. It is possible to prevent the generation of static electricity on the material, and the effect of applying the above-described sliding material to the electric tool, such as no adhesion of processing scraps to the bottom surface of the base material and no hindrance to work.

  Further, since the sliding material can be replaced, the sliding material can be replaced when the sliding surface is damaged and deteriorated by handling. In addition, the static electricity removing effect can be continued by replacing the sliding material. Furthermore, the sliding material can be easily replaced by adhering the sliding material to the base with a double-sided tape.

It is a perspective view which shows an example of the electric tool provided with the sliding material of this invention. It is a partial expanded sectional view of the base periphery. It is a partial cross section figure showing an example of the structure of an electric tool.

  The electric tool provided with the sliding material for electric tools of this invention is demonstrated based on FIG. 1 and FIG. FIG. 1 is a perspective view of a portable circular saw as an embodiment of the electric tool of the present invention, and FIG. 2 is a partially enlarged sectional view of the periphery of the base of the electric tool of FIG. As shown in FIG. 1, a portable circular saw 1 includes a saw blade 2, a housing 3 that houses an electric motor (not shown), a saw cover 4 that is provided so as to partially cover the saw blade 2, and a saw blade. And a base 5 having an opening 5a for projecting 2 on the bottom surface 5b. The saw blade 2 is rotationally driven by an electric motor through a gear or the like. The base 5 is fixed to the housing 3 and the saw cover 4. Here, the sliding material 6 is provided on the bottom surface 5 b of the base 5. The basic structure inside the power tool is the same as that of the conventional product shown in FIG.

  The sliding material 6 is the sliding material for electric tools of the present invention. The sliding material 6 is composed of a resin sheet. This resin sheet has conductivity and a sliding resistance smaller than the sliding resistance of the base itself. For this reason, generation | occurrence | production and accumulation | storage of static electricity can be suppressed and adhesion of processing wastes, such as a plastic workpiece, can be prevented, making it possible to improve the slip property with the workpiece which is a counterpart material.

  The sliding material 6 is bonded to the bottom surface 5b of the base 5 with an adhesive or an adhesive. In particular, by using an adhesive such as a double-sided tape, when a resin sheet is scratched, torn, or peeled off, it can be replaced with a new sheet material. The sliding member 6 has an opening 6c that communicates with the opening 5a of the base 5, and the saw blade 2 protrudes from the opening 6c.

  Since the portable circular saw 1 has a configuration in which the sliding material 6 is provided, the material of the base 5 is not particularly limited, and the base material and structure of the existing electric tool can be applied as they are. Generally, iron, aluminum or stainless steel is used as the material of the base 5, but it may be made of hard synthetic resin or ceramic. The portable circular saw 1 moves the circular saw in the cutting direction while pressing the base 5 (with the sliding material 6 on the bottom surface 5b) against the workpiece to be mated, and cuts the workpiece with the saw blade 2. . During the cutting operation, the work material slides in close contact with the sliding material 6 provided on the bottom surface of the base 5.

  FIG. 2 shows a partially enlarged sectional view around the base. In the form shown in FIG. 2, the sliding material 6 is bonded to the base 5 via an adhesive double-sided tape 7. The surface of the sliding material 6 on the workpiece side becomes the sliding surface 6a. Further, a surface 6 b opposite to the sliding surface 6 a is an adhesive surface with the base 5. As the sliding material 6, for example, a resin sheet in which a double-sided tape 7 is bonded in advance to an opposite surface 6 b that is one side can be used. Such a sliding material 6 is obtained by cutting a resin sheet having a double-sided tape attached on one side thereof into a predetermined shape (appearance shape and opening shape) matched to the base with a press or a plotter cutter. The obtained sliding material is bonded to the bottom surface 5 b of the base 5 via the double-sided tape 7. More specifically, the bottom surface 5b of the base 5 is degreased, the release paper provided on the adhesive surface of the double-sided tape 7 to the base 5 is peeled off, and the exposed double-sided tape 7 and the base 5 are brought into close contact with each other. Glue.

  If the resin sheet is torn or worn during use, and it becomes difficult to use, remove the sliding material 6 from the base 5, peel off the release paper from the new sliding material, and use the double-sided tape as the base. A sliding material 6 is attached to 5.

  The thickness of the resin sheet which is the sliding material 6 is preferably 0.2 mm to 0.8 mm. The resin sheet is a sheet having a constant thickness over the entire surface of the sheet. When the resin sheet is thinner than 0.2 mm, the tear resistance may be inferior depending on the use conditions. On the other hand, when the resin sheet exceeds 0.8 mm, it may be easily peeled off from the base.

  Moreover, it is preferable that the thickness of adhesive layers, such as an adhesive, is 20 micrometers-200 micrometers. When the double-sided tape 7 is used, the thickness of the double-sided tape 7 is preferably in the above range (20 μm to 200 μm). As the double-sided tape 7, one having a pressure-sensitive adhesive layer such as a silicone pressure-sensitive adhesive layer on both sides of the resin substrate can be used, and the thickness of the double-sided tape is the total thickness (not including the release paper). When the thickness of a double-sided tape or the like is thinner than 20 μm, the adhesive layer is also thin, and the adhesive effect may not be sufficiently obtained. On the other hand, when the thickness of the double-sided tape or the like exceeds 200 μm, the flatness on the sliding surface of the resin sheet may be deteriorated. Further, the thickness of the entire sliding material combined with the resin sheet becomes too thick (for example, more than 1 mm), and there is a risk that the workpiece is caught by the step at the end of the sheet.

  The present invention is characterized in that the sliding member 6 is composed of a conductive resin sheet. As this resin sheet, the sheet | seat of the resin composition containing an electroconductive compounding agent is mentioned. The method for forming the sheet material can be appropriately determined according to the resin material used as the base resin. Examples of the conductive compounding agent include carbon black, carbon fiber, carbon nanotube, fullerene, natural graphite, artificial graphite, carbon-based compounding agent such as glassy carbon obtained by carbonizing phenol resin or furan resin, conductive ceramic powder, metal powder. And other metal-based compounding agents. Here, the metal-based compounding agent is not preferable because it has hard characteristics and may cause scratches when the workpiece to be processed is made of plastic. Therefore, a carbon-type compounding agent is preferable, and carbon black which is carbon powder is the most desirable among them. Carbon black efficiently releases static electricity and does not damage the mating material. Carbon black has no shape anisotropy and is excellent in cost performance.

Carbon black produced by any known method can be used, but furnace black, acetylene black, and ketjen black (registered trademark) are preferably used from the viewpoint of conductivity. Among these, ketjen black is conductive. It is more preferable because of its excellent properties. Ketjen black preferably has a primary particle size of 30 to 38 nm. When the primary particle size is in this range, a sufficient volume resistance value can be obtained even with a small amount. Further, the BET specific surface area of ketjen black is preferably 1000 to 1500 m ² / g. Within this specific surface area range, the stability of the volume resistance value is excellent even with a small amount. As such a ketjen black, a ketjen black EC-600JD made by a ketjen black international company is mentioned.

  Synthetic resins that serve as the base resin of the resin composition forming the resin sheet include fluorine resins such as polytetrafluoroethylene (PTFE) resin and tetrafluoroethylene-perfluoroalkyl vinyl ether copolymer (PFA) resin, and low density polyethylene. Examples thereof include polyethylene (PE) resins such as resins, high-density polyethylene resins, and ultrahigh molecular weight polyethylene (UHMWPE) resins, polyamide (PA) resins, polyacetal (POM) resins, and polyethylene terephthalate (PET) resins. In particular, UHMWPE resin is preferable because it has high wear resistance and a long life as a sliding material.

  The UHMWPE resin suitable as the synthetic resin is a non-melt moldable UHMWPE resin that cannot be melt-molded such as injection molding or extrusion molding. UHMWPE resin is a PE resin in which the molecular weight of 20,000 to 300,000 of PE resin, which is a crystalline thermoplastic resin obtained by polymerizing ethylene, is increased to 500,000 to 7 million. It has adhesiveness and low friction characteristics, and has high insulation and is easily charged with static electricity. UHMWPE resin also has improved wear resistance and excellent low friction properties. However, among UHMWPE resins, especially those having a molecular weight exceeding 1 million have extremely high viscosity at the time of melting and hardly flow. Therefore, it is very difficult to mold by ordinary injection molding or extrusion molding. After forming the material by ram extrusion, it is processed into a desired shape by machining. Such a non-melt moldable UHMWPE resin has a lower friction characteristic than a melt-moldable UHMWPE resin and is excellent in wear resistance.

  The UHMWPE resin that can be used in the present invention is UHMWPE resin powder having a weight average molecular weight of 1,000,000 to 4,000,000. Examples of such UHMWPE powder include Mitsui Chemicals, trade name Hi-Zex Million (weight average molecular weight 500,000 to 6,000,000), and Mipperon (weight average molecular weight 2 million). Further, the UHMWPE resin particles are preferably non-spherical. Among non-spherical particles, it is desirable that each particle is an irregularly shaped particle having a different shape rather than a particle having a specific shape. The UHMWPE resin of irregularly shaped particles causes a lot of contact between the particles even when a compounding agent (such as a conductive compounding agent) is blended during compression molding, and the particles are easily fused. Excellent wear resistance.

  When a non-melt moldable UHMWPE resin is used as the base resin, the resin sheet can be manufactured by the following manufacturing method. Weigh each raw material to make a uniform mixture. This uniform mixture is put into a molding die, and a billet as a molding material is formed by compression molding including preliminary molding, firing, and main molding. The billet is attached to a lathe, and a sheet material is obtained by skiving like a wig.

  If necessary, the resin composition forming the resin sheet may be blended with other compounding agents such as a lubricity imparting agent as long as the conductivity and slipperiness are not impaired. Examples of the lubricity-imparting agent include PTFE resin powder, silicone resin powder, and graphite powder. By blending these powders, the low friction characteristics of the resin sheet are improved. When blending such a lubricity imparting agent, for example, 0.5 to 5 parts by weight is blended with respect to 100 parts by weight of the base resin.

As for the conductive properties of the resin sheet, the volume resistance value is preferably in the range of 1.0 × 10 ^{4 to} 1.0 × 10 ¹⁰ Ωcm. By having a volume resistance value in such a range, generation and accumulation of static electricity can be suppressed even when sliding with the workpiece, and adhesion of machining waste can be prevented. In order to make a volume resistance value into the said range, what is necessary is just to mix | blend 2-15 weight part of electroconductive compounding agents with respect to 100 weight part of base resins in the resin composition which forms a resin sheet. For example, when using non-melt-moldable UHMWPE resin particles (powder) as the base resin, and carbon black as a conductive compounding agent, and compression molding, the above-mentioned compounding ratio is used to form nanoparticles. A certain carbon black can be uniformly dispersed between the particles of the UHMWPE resin, and the volume resistance value (1.0 × 10 ^{4 to} 1.0 × 10 ¹⁰ Ωcm) can be realized even when processed into a sheet material.

  The electric power tool of the present invention is an electric power tool provided with a base, and the sliding material of the present invention is provided on the bottom surface of the base. In particular, the present invention is an electric tool for processing a plastic workpiece such as a plastic decorative board, a plywood with plastic decorative paper, a plastic board, and a corrugated board. Since the sliding material is made of a resin sheet having conductivity, it is possible to prevent the generation of static electricity on the plastic workpiece as described above, and there is no adhesion of processing waste to the bottom of the base, hindering work. Don't be. In addition, since the sliding material is bonded to the double-sided tape so that the sliding material can be replaced, the sliding material can be easily replaced when the sliding surface of the resin sheet is damaged and deteriorated by handling.

  The sliding material for an electric power tool of the present invention is excellent in slipping property against a work material, can prevent generation of static electricity on a plastic work material, and can be easily replaced. , And can be suitably used for an electric tool provided with a base, for example, an electric circular saw, a lathe, a router, and a jigsaw.

1 Portable circular saw (electric tool)
2 Saw blade 3 Housing 4 Saw cover 5 Base 6 Sliding material 7 Double-sided tape

Claims (8)

A sliding material provided on the bottom surface of the base of the electric tool including the base and sliding with the workpiece,
The sliding material for a power tool, wherein the sliding material is made of a conductive resin sheet.   The said resin sheet is a sheet | seat of the resin composition containing an electroconductive compounding agent, The sliding material for electric tools of Claim 1 characterized by the above-mentioned.   The sliding material for electric tools according to claim 2, wherein the conductive compounding agent is carbon black.   The said resin sheet is a sheet | seat of the resin composition which uses ultra high molecular weight polyethylene resin as a base resin, The sliding material for electric tools of any one of Claim 1- Claim 3 characterized by the above-mentioned.   The thickness of the said resin sheet is 0.2 mm-0.8 mm, The sliding material for electric tools of any one of Claim 1- Claim 4 characterized by the above-mentioned.   The said sliding material for electric tools has a double-sided tape adhere | attached on the one surface of the said resin sheet, and is adhere | attached on the said base through this double-sided tape. The sliding material for electric tools of any one of these.   It is an electric tool provided with a base, and a sliding material is provided on the bottom surface of the base, and the sliding material is the sliding material according to any one of claims 1 to 5. A featured electric tool.   The power tool according to claim 7, wherein the sliding material is bonded to the base via a double-sided tape and can be replaced.

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