WO2013051580A1 - Power tool, and power tool manufacturing method - Google Patents

Power tool, and power tool manufacturing method Download PDF

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Publication number
WO2013051580A1
WO2013051580A1 PCT/JP2012/075556 JP2012075556W WO2013051580A1 WO 2013051580 A1 WO2013051580 A1 WO 2013051580A1 JP 2012075556 W JP2012075556 W JP 2012075556W WO 2013051580 A1 WO2013051580 A1 WO 2013051580A1
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Prior art keywords
power tool
lubricant
ball
manufacturing
amount
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PCT/JP2012/075556
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French (fr)
Japanese (ja)
Inventor
直樹 藤松
亮 砂塚
雄志 高橋
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株式会社マキタ
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Publication of WO2013051580A1 publication Critical patent/WO2013051580A1/en

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B23/00—Portable grinding machines, e.g. hand-guided; Accessories therefor
    • B24B23/02—Portable grinding machines, e.g. hand-guided; Accessories therefor with rotating grinding tools; Accessories therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B23/00—Portable grinding machines, e.g. hand-guided; Accessories therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B24—GRINDING; POLISHING
    • B24B—MACHINES, DEVICES, OR PROCESSES FOR GRINDING OR POLISHING; DRESSING OR CONDITIONING OF ABRADING SURFACES; FEEDING OF GRINDING, POLISHING, OR LAPPING AGENTS
    • B24B41/00—Component parts such as frames, beds, carriages, headstocks
    • B24B41/007—Weight compensation; Temperature compensation; Vibration damping
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B25—HAND TOOLS; PORTABLE POWER-DRIVEN TOOLS; MANIPULATORS
    • B25F—COMBINATION OR MULTI-PURPOSE TOOLS NOT OTHERWISE PROVIDED FOR; DETAILS OR COMPONENTS OF PORTABLE POWER-DRIVEN TOOLS NOT PARTICULARLY RELATED TO THE OPERATIONS PERFORMED AND NOT OTHERWISE PROVIDED FOR
    • B25F5/00—Details or components of portable power-driven tools not particularly related to the operations performed and not otherwise provided for
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16F—SPRINGS; SHOCK-ABSORBERS; MEANS FOR DAMPING VIBRATION
    • F16F15/00—Suppression of vibrations in systems; Means or arrangements for avoiding or reducing out-of-balance forces, e.g. due to motion
    • F16F15/32—Correcting- or balancing-weights or equivalent means for balancing rotating bodies, e.g. vehicle wheels
    • F16F15/36—Correcting- or balancing-weights or equivalent means for balancing rotating bodies, e.g. vehicle wheels operating automatically, i.e. where, for a given amount of unbalance, there is movement of masses until balance is achieved
    • F16F15/363—Correcting- or balancing-weights or equivalent means for balancing rotating bodies, e.g. vehicle wheels operating automatically, i.e. where, for a given amount of unbalance, there is movement of masses until balance is achieved using rolling bodies, e.g. balls free to move in a circumferential direction

Definitions

  • the present invention relates to a power tool having a ball balancer and a method for manufacturing the power tool.
  • Japanese Patent Laid-Open No. 2001-300841 describes a grinder equipped with a vibration isolator.
  • This vibration isolator has a plurality of balance balls and is attached to rotate integrally with a grindstone receiver disposed on the outer periphery of the drive shaft.
  • the balance ball moves, and the balance ball moves so that the center of gravity of the rotating part and the center of rotation of the driving shaft coincide. This prevents the rotating part from vibrating.
  • an object of the present invention is to provide a technique related to a ball balancer that allows a ball to operate smoothly.
  • a rotary shaft to which a tip tool is attached and a ball balancer that rotates integrally with the rotary shaft are provided.
  • the ball balancer includes a plurality of balls, a ball storage member provided with a rotation area having a predetermined volume for holding the balls so as to be rotatable around a rotation axis, and a lubricant filled in the rotation area. is doing.
  • the filling amount of the lubricant is a filling amount that reduces the vibration value generated in the power tool when the power tool is driven by smoothly rotating the ball.
  • the filling amount of the lubricant is set to an amount capable of smoothly rotating the ball, the ball balancer can be operated efficiently. Thereby, the vibration value which arises in a power tool can be reduced.
  • the filling amount of the lubricant is such that the filling rate X with respect to the volume of the rotating region is expressed by the following formula (1) with respect to the value ⁇ corresponding to the viscosity of the lubricant. It is an amount corresponding to the filling rate satisfying.
  • the “volume of the rotation area” is a volume obtained by subtracting the total volume of the balls from the volume in which the balls can rotate in the rotation area.
  • the lubricant has a viscosity of VG100 or less, and the filling amount of the lubricant is an amount having a filling rate of 27% or less with respect to the volume of the rotating region.
  • the “volume of the rotation area” is a volume obtained by subtracting the total volume of each ball from the volume in which the ball in the rotation area can rotate. Note that VG is a symbol representing the ISO viscosity grade, and the numerical value following VG is the midpoint kinematic viscosity expressed in units of mm 2 / s.
  • a ball balancer capable of smoothly operating a ball by appropriately setting the viscosity and filling amount of the lubricant. Therefore, the vibration which a power tool generate
  • the power tool is a grinder.
  • vibration generated by the power tool can be efficiently reduced with respect to the grinder as the power tool.
  • the power tool includes a rotating shaft to which a tip tool is attached and a ball balancer that rotates integrally with the rotating shaft.
  • the ball balancer includes a plurality of balls, a ball storage member provided with a rotation area having a predetermined volume for holding the balls so as to be rotatable around a rotation axis, and a lubricant filled in the rotation area. is doing. Then, the filling amount of the lubricant is determined so that the vibration value generated in the power tool when the power tool is driven is equal to or less than a predetermined value, and the determined filling amount of the lubricant is filled in the rotation region.
  • a ball balancer is formed.
  • the present invention it is possible to determine the amount of lubricant filling so that the vibration value is equal to or less than a predetermined value, and appropriately set the amount of lubricant filling while suppressing vibration generated in the power tool.
  • a power tool equipped with a balancer can be manufactured.
  • the filling amount of a lubricant is the following with respect to the value (micro
  • the “volume of the rotation area” is a volume obtained by subtracting the total volume of the balls from the volume in which the balls can rotate in the rotation area.
  • the ball balancer that can smoothly operate the ball by setting the filling rate according to the viscosity of the lubricant.
  • the power tool provided with the ball balancer which can reduce the vibration which a power tool generate
  • the viscosity of a lubricant is VG100 or less
  • the filling amount of a lubricant is an amount whose filling amount with respect to the volume of a rotation area
  • region is 27% or less.
  • the “volume of the rotation area” is a volume obtained by subtracting the total volume of each ball from the volume in which the ball in the rotation area can rotate.
  • VG is a symbol representing the ISO viscosity grade
  • the numerical value following VG is the midpoint kinematic viscosity expressed in units of mm 2 / s.
  • a ball balancer capable of smoothly operating a ball by appropriately setting the viscosity and filling amount of the lubricant.
  • the power tool provided with the ball balancer which can reduce the vibration which a power tool generate
  • the filling amount of a lubricant is determined so that the vibration value which arises in a power tool may be 2.5 m / s ⁇ 2 > or less in a hand-arm vibration value. ing.
  • the filling amount of the lubricant can be appropriately determined so that the vibration value generated in the power tool is 2.5 m / s 2 or less in terms of hand-arm vibration value.
  • the daily vibration exposure countermeasure value of 2.5 m / s 2 is specified. That is, to reduce the possibility of symptoms related to hand-arm vibration syndrome to users of hand-held vibration and striking equipment, tools and workpieces when the daily vibration exposure countermeasure value of 2.5 m / s 2 is achieved. It is a value that is considered to be.
  • This 2.5 m / s 2 daily vibration exposure control value is generally accepted by medical professionals, scientists and government agencies, research institutions and industries in the United States and other countries.
  • a power tool is a grinder.
  • FIG. 2 is a cross-sectional view taken along line II-II in FIG. It is a plane sectional view of a ball balancer.
  • FIG. 4 is a sectional view taken along line IV-IV in FIG. 3. It is a flowchart which determines the filling rate of the lubricating oil of a ball balancer. It is a figure which shows the relationship between the filling rate of lubricating oil, and the vibration value of a grinder.
  • a grinder will be described as an example of a power tool.
  • This grinder is a power tool that rotates a grinding tool such as a grinding tool or a polishing tool or a tip tool such as a cutting tool by a motor to perform grinding, polishing, cutting, or the like on a workpiece.
  • the grinder 1 is mainly composed of a main housing 10, a gear housing 20, a rear cover 30, and a wheel cover 40.
  • the main housing 10 is a substantially cylindrical housing and houses the motor 100.
  • the rotation shaft 101 of the motor 100 is disposed so as to protrude toward the gear housing 20.
  • the gear housing 20 is provided on one side of the main housing 10 and houses the first bevel gear 200, the second bevel gear 201, the spindle 202, the bearings 203, 204, and the like.
  • the first bevel gear is externally mounted on the rotating shaft 101 of the motor 100.
  • the second bevel gear 201 is disposed so as to be screwed with the first bevel gear 200.
  • a spindle 202 is disposed at the center of the second bevel gear 201, and the second bevel gear 201 and the spindle 202 rotate together. Thereby, the rotation output of the motor 100 is converted into a rotational force around the axis of the spindle 202 orthogonal to the rotation axis 101.
  • the spindle 202 is held by two bearings 203 and 204.
  • the rear cover 30 is provided on the opposite side of the main housing 10 from the gear housing 20 and accommodates the power supply wiring portion 300.
  • the power supply wiring unit 300 is provided with a power supply cord 301 that supplies current from an external power supply and a switch 302 that switches ON / OFF of the drive of the grinder 1.
  • the power supply wiring unit 300 is electrically connected to the motor 100.
  • the wheel cover 40 is a substantially semicircular part that is detachably attached to the outside of the gear housing 20.
  • a ball balancer 400 is attached to a portion of the spindle 202 that protrudes outside the gear housing 20. Further, an outer flange 41 that can be attached to and detached from the spindle 202 is screwed to the spindle 202 at the tip of the spindle 202.
  • the grindstone 2 is detachably held between the ball balancer 400 and the outer flange 41.
  • the wheel cover 40 is configured so as to cover the outside of the grindstone 2 attached to the spindle 202 half a circumference. Thereby, the wheel cover 40 suppresses scattering of fragments of the workpiece processed by the grindstone 2 and protects the user from the rotating grindstone 2.
  • This grindstone 2 is an implementation structural example corresponding to the "tip tool" of the present invention.
  • the ball balancer 400 is mainly composed of a balancer body 401, balls 402, and a balancer cover 403.
  • the balancer body 401 is a metal substantially disk-shaped member.
  • a through hole 404 through which the spindle 202 is inserted is formed at the center of the balancer body 401.
  • a groove 405 opened on one surface of the balancer body 401 is formed around the through hole 404.
  • the ball 402 is a metal sphere, and eight balls 402 are held in the groove 405 so as to be movable around the through hole 404 in the groove 405.
  • a balancer cover 403 is disposed on one surface of the balancer body 401 so as to close the opening of the groove 405. Note that lubricating oil (not shown) for smooth movement of the ball 402 is enclosed in the groove 405.
  • the balancer body 401 and the balancer cover 403 are an implementation configuration example corresponding to the “ball storage member” of the present invention.
  • the groove 405 is an implementation configuration example corresponding to the “rotation region” of the present invention.
  • the grinder 1 configured as described above is supplied with electric power from the external power supply to the motor 100 via the electric wiring unit 300 when the switch 302 is operated. As a result, the motor 100 is driven to rotate, and the first bevel gear 200 attached to the rotating shaft 101 rotates. When the first bevel gear 200 and the second bevel gear 201 are screwed together and rotated, the rotation output of the motor 100 is converted into a rotational force around the spindle 202 and rotated integrally with the second bevel gear 201. The grindstone 2 mounted on the spindle 202 is rotated. The workpiece can be processed by pressing the rotating grindstone 2 against the workpiece.
  • the grinder 1 vibrates.
  • the ball balancer 400 attached to the spindle 202 rotates integrally with the spindle 202.
  • the plurality of balls 402 rotate in the groove 405 so as to reduce the distance between the center of gravity of the grindstone 2 and the like rotating together with the spindle 202 and the rotation axis of the spindle 202. That is, in the present embodiment, vibration generated in the grinder 1 by the ball balancer 400 is reduced.
  • the amount of lubricating oil charged is determined so that the vibration value generated in the grinder 1 when the grinder 1 is driven is less than or equal to a predetermined value by smoothly rotating the ball 402. is doing.
  • the ball balancer 400 is formed by filling the rotation region with the determined amount of lubricating oil.
  • This filling amount is determined from the relationship between the viscosity of the lubricating oil and the filling rate of the lubricating oil.
  • the filling rate is calculated as the filling amount of the lubricating oil with respect to the volume obtained by subtracting the sum of the volumes of the eight balls 402 from the volume of the region in which the balls 402 can rotate in the groove 405.
  • the applicant sets the filling rate of the lubricating oil based on experiments conducted in advance. The experiment will be described with reference to FIG.
  • step 1 (S1) is a step of “setting the dimensions of the ball balancer 400”.
  • Step 2 (S2) is a step of “setting lubricating oil to be filled”.
  • Step 3 (S3) is a step of “measuring the relationship between the filling rate and the vibration value”.
  • Step 4 (S4) is a step of “determining the filling rate of the lubricating oil”.
  • each dimension of the ball balancer 400 is set (S1).
  • the dimensions of the ball balancer 400 in FIGS. 3 and 4 are as follows.
  • the inner diameter R1 of the groove 405 is 36 mm
  • the outer diameter R2 is 55 mm
  • the depth D is 9.8 mm.
  • the diameter of the ball 402 is 8.73 mm.
  • the lubricating oil filled in the groove 405 is set (S2).
  • Shell (registered trademark) terrace oil is used as the lubricating oil.
  • VG32, VG68, VG100 lubricating oil
  • S3 the relationship between the filling rate and the vibration value
  • the acceleration is measured in a state where the grinder 1 is held at two points in the axial direction of the rotary shaft 101 so that the rotary shaft 101 of the motor 100 matches the horizontal direction and the spindle 202 matches the vertical direction.
  • the acceleration of each of the three axes was measured with a pickup. Then, the measured acceleration was appropriately filtered, and a value obtained by synthesizing the accelerations in the three axis directions was set as a vibration value. The relationship between the filling rate of the lubricating oil and the vibration value was obtained.
  • FIG. 6 is a graph showing the relationship between the filling rate of the lubricating oil and the vibration value as an experimental result in S3.
  • the vertical axis of the graph shown in FIG. 6 represents a vibration value, and is a value obtained by synthesizing accelerations in three axis directions.
  • the unit of vibration value is (m / s 2 ).
  • the horizontal axis of the graph shown in FIG. 6 represents the filling rate of the lubricating oil, and the unit of the filling rate is (%).
  • the lubricating oil has a viscosity of VG100 or less and a filling rate of 27% or less that gives a vibration value of 2.5 m / s 2 or less.
  • ⁇ corresponding to the viscosity
  • the value following the symbol VG representing the ISO viscosity grade was used.
  • This vibration value corresponds to the daily vibration exposure countermeasure value of 2.5 m / s 2 stipulated in the European Union Human Body Vibration Directive 2002/44 / EC.
  • a predetermined vibration value F is set, and the filling rate of the lubricating oil according to the viscosity can be determined so as to satisfy the formula (4).
  • the predetermined vibration value F may be set to 2.5, and the filling rate of the lubricating oil according to the viscosity may be determined so as to satisfy Formula (5).
  • the ball balancer 400 is formed by filling the groove 405 with a filling amount of lubricating oil corresponding to the filling rate determined as described above. Then, the grinder 1 is formed by attaching the ball balancer 400 to the spindle 202 integrally.
  • the filling rate is defined as the filling amount of the lubricating oil with respect to the volume obtained by subtracting the volume of the ball 402 (the total volume of each ball 402) from the volume of the region in which the ball 402 can rotate in the groove 405. is doing.
  • the filling rate may be defined as the filling amount of the lubricating oil with respect to the volume of the groove 405, and the relationship between the filling rate and the vibration value may be calculated to determine the filling amount of the lubricating oil.
  • the ball 402 can be operated smoothly by setting the filling rate of the lubricating oil according to the viscosity of the lubricating oil.
  • the grinder 1 provided with the ball balancer 400 with which the ball 402 operates smoothly can be formed.
  • the vibration generated by the grinder 1 can be efficiently reduced.
  • the filling amount of lubricating oil can be reduced compared with the case where the groove 405 is filled with lubricating oil, and the grinder 1 can be reduced in cost.
  • Shell (registered trademark) terrace oil is used as the lubricating oil.
  • the filling rate can be set according to the viscosity of the lubricant even when other lubricants are used. It is.
  • the vibration value of 2.5 corresponds to the vibration value of 2.5 m / s 2 defined in the European Union Human Body Vibration Directive 2002/44 / EC.
  • the predetermined vibration value F can be appropriately set according to the required performance.
  • the vibration value F may be a value corresponding to the vibration value.
  • the vibration value F may be the vibration value itself, or may be a value obtained by making the vibration value dimensionless.
  • the value ⁇ following the symbol VG representing the ISO viscosity grade is used as the value ⁇ corresponding to the viscosity, but the value of the viscosity itself may be used.
  • a value obtained by making the viscosity dimensionless may be used.
  • the grinder is taken as an example of the power tool, but it is not limited to this.
  • the present invention can be applied to a hammer drill driven by a motor, a brush cutter driven by an engine, or the like.
  • the power tool according to the present invention can be configured in the following manner.
  • (Aspect 1) “Rotating shaft to which the tip tool is attached, A ball storage member provided with a plurality of balls and a rotation area having a predetermined volume for rotatably holding the balls around the rotation shaft while rotating integrally with the rotation shaft;
  • a power tool comprising a ball balancer having a lubricant filled in the region, The filling amount of the lubricant is a filling amount that reduces a vibration value generated in the power tool when the power tool is driven by smoothly rotating the ball, and is based on the volume of the rotation region.
  • the vibration value is A power tool characterized by an amount corresponding to a filling rate satisfying the following mathematical formula (6) that is equal to or less than a predetermined vibration value F.
  • the following aspect can be comprised in the manufacturing method of the power tool which concerns on this invention.
  • (Aspect 2) “Rotating shaft to which the tip tool is attached, A ball housing member that rotates integrally with the rotation shaft and that has a plurality of balls and a rotation area having a predetermined volume for rotatably holding the balls around the rotation shaft; and the rotation A method of manufacturing a power tool comprising a ball balancer having a lubricant filled in a region, By smoothly rotating the ball, the amount of the lubricant filled is adjusted so that the vibration value generated in the power tool when the power tool is driven is less than or equal to a predetermined value.
  • the filling factor X with respect to the volume of the region is based on the coefficients a and b determined by the viscosity of the lubricant, the coefficient c determined by the roundness and surface roughness of the ball, and the value ⁇ corresponding to the viscosity of the lubricant.
  • the vibration value is determined to be an amount corresponding to the filling rate that satisfies the following mathematical formula (7) that is equal to or less than the predetermined vibration value F, A method of manufacturing a power tool, wherein the ball balancer is formed by filling the rotation region with the determined amount of the lubricant.
  • grinder 2 grindstone 10 main housing 20 gear housing 30 rear cover 40 wheel cover 41 outer flange 100 motor 101 rotating shaft 200 first bevel gear 201 second bevel gear 300 power wiring section 301 power cord 302 switch 400 ball balancer 401 balancer body 402 ball 403 Balancer cover 404 Through hole 405 Groove

Abstract

[Problem] To provide ball balancer technology for smooth ball action. [Solution] A grinder (1) is provided with a spindle (202) on which a grindstone (2) is installed, and a ball balancer (400) that rotates as a unit with the spindle (202). The ball balancer (400) is provided with multiple balls (402) and a groove (405) that holds the balls (402) around the spindle (202) so as to allow rotation. The groove (405) is filled with lubricant. The lubricant filling rate (X) with respect to the volume of the groove (405) and a value µ, which corresponds to the viscosity of the lubricant, satisfy the numeric formula (1).

Description

動力工具、および動力工具の製造方法Power tool and method of manufacturing power tool
　本発明は、ボールバランサを有する動力工具、および動力工具の製造方法に関する。 The present invention relates to a power tool having a ball balancer and a method for manufacturing the power tool.
　特開２００１－３００８４１号には、防振装置を備えたグラインダが記載されている。この防振装置は、複数のバランスボールを有し、駆動軸の外周に配置された砥石受けと一体的に回転するように取り付けられている。砥石を含む回転部分の重心が駆動軸の回転中心と一致しない場合には、バランスボールが移動して、回転部分の重心と駆動軸の回転中心とが一致するようにバランスボールが移動する。これにより、回転部分が振動することを防止している。 Japanese Patent Laid-Open No. 2001-300841 describes a grinder equipped with a vibration isolator. This vibration isolator has a plurality of balance balls and is attached to rotate integrally with a grindstone receiver disposed on the outer periphery of the drive shaft. When the center of gravity of the rotating part including the grindstone does not coincide with the center of rotation of the drive shaft, the balance ball moves, and the balance ball moves so that the center of gravity of the rotating part and the center of rotation of the driving shaft coincide. This prevents the rotating part from vibrating.
特開２００１－３００８４１号公報JP 2001-300841 A
　ところで、ボールの移動によって振動を抑制するボールバランサは、ボールの移動は円滑であることが望ましい。そのため、ボールバランサのボールが移動する領域には、潤滑油が必要である。しかしながら、ボールが移動する領域に潤滑油が充満されていると、潤滑油の流体抵抗によりボールの移動を妨げる力が発生する。すなわち、ボールの円滑な移動が阻害され、動力工具の振動を低減させるボールバランサの効果を希釈させるおそれがある。そこで、本発明は、上記に鑑み、ボールが円滑に動作するためのボールバランサに関する技術を提供することを目的とする。 By the way, it is desirable that the ball balancer that suppresses vibration by moving the ball smoothly moves the ball. Therefore, lubricating oil is required in the region where the ball of the ball balancer moves. However, if the region in which the ball moves is filled with lubricating oil, a force that prevents the ball from moving is generated due to the fluid resistance of the lubricating oil. That is, the smooth movement of the ball is hindered, and the effect of the ball balancer that reduces the vibration of the power tool may be diluted. Therefore, in view of the above, an object of the present invention is to provide a technique related to a ball balancer that allows a ball to operate smoothly.
　上記課題を解決するため、本発明に係る動力工具の好ましい形態によれば、先端工具が取り付けられる回転軸と、その回転軸と一体的に回転するボールバランサを備えている。当該ボールバランサは、複数のボールと、ボールを回転軸周りに回動可能に保持する所定の容積を有する回動領域が設けられたボール収納部材と、回動領域に充填された潤滑剤を有している。そして、潤滑剤の充填量は、ボールを円滑に回動させることによって、動力工具が駆動したときの当該動力工具に生じる振動値を低減させる充填量である。 In order to solve the above-mentioned problems, according to a preferred embodiment of the power tool according to the present invention, a rotary shaft to which a tip tool is attached and a ball balancer that rotates integrally with the rotary shaft are provided. The ball balancer includes a plurality of balls, a ball storage member provided with a rotation area having a predetermined volume for holding the balls so as to be rotatable around a rotation axis, and a lubricant filled in the rotation area. is doing. And the filling amount of the lubricant is a filling amount that reduces the vibration value generated in the power tool when the power tool is driven by smoothly rotating the ball.
　本発明によれば、潤滑剤の充填量は、ボールを円滑に回動させることができる量に設定されているため、ボールバランサを効率よく作動させることができる。これにより、動力工具に生じる振動値を低減させることができる。 According to the present invention, since the filling amount of the lubricant is set to an amount capable of smoothly rotating the ball, the ball balancer can be operated efficiently. Thereby, the vibration value which arises in a power tool can be reduced.
　本発明に係る動力工具の更なる形態によれば、潤滑剤の充填量は、回動領域の容積に対する充填率Ｘが、当該潤滑剤の粘度に対応する値μに対して、下記数式（１）を満たす充填率に対応する量である。この「回動領域の容積」とは、回動領域におけるボールが回動可能な容積から、ボールの容積の合計を差し引いた容積である。 According to the further form of the power tool according to the present invention, the filling amount of the lubricant is such that the filling rate X with respect to the volume of the rotating region is expressed by the following formula (1) with respect to the value μ corresponding to the viscosity of the lubricant. It is an amount corresponding to the filling rate satisfying. The “volume of the rotation area” is a volume obtained by subtracting the total volume of the balls from the volume in which the balls can rotate in the rotation area.
数式（１）
Figure JPOXMLDOC01-appb-I000003
Formula (1)
Figure JPOXMLDOC01-appb-I000003
　本形態によれば、潤滑剤の粘度に応じて、充填率を設定することで、ボールを円滑に動作させることができるボールバランサが提供される。これにより、動力工具が発生する振動を効率よく低減することができる。 According to this embodiment, it is possible to provide a ball balancer that can smoothly operate the ball by setting the filling rate according to the viscosity of the lubricant. Thereby, the vibration which a power tool generate | occur | produces can be reduced efficiently.
　本発明に係る動力工具の更なる形態によれば、潤滑剤は、粘度がＶＧ１００以下であり、かつ当該潤滑剤の充填量は、回動領域の容積に対する充填率が２７％以下の量である。この「回動領域の容積」とは、回動領域におけるボールが回動可能な容積から、各ボールの容積の合計を差し引いた容積である。なお、ＶＧとは、ＩＳＯの粘度グレードを表す記号であり、ＶＧに続く数値はその中点動粘度を ｍｍ２／ｓ の単位で表したものである。 According to the further form of the power tool according to the present invention, the lubricant has a viscosity of VG100 or less, and the filling amount of the lubricant is an amount having a filling rate of 27% or less with respect to the volume of the rotating region. . The “volume of the rotation area” is a volume obtained by subtracting the total volume of each ball from the volume in which the ball in the rotation area can rotate. Note that VG is a symbol representing the ISO viscosity grade, and the numerical value following VG is the midpoint kinematic viscosity expressed in units of mm 2 / s.
　本形態によれば、潤滑剤の粘度と充填量を適切に設定することで、ボールを円滑に動作させることができるボールバランサが提供される。これにより、動力工具が発生する振動を効率よく低減することができる。 According to this embodiment, a ball balancer capable of smoothly operating a ball by appropriately setting the viscosity and filling amount of the lubricant is provided. Thereby, the vibration which a power tool generate | occur | produces can be reduced efficiently.
　本発明に係る動力工具の更なる形態によれば、動力工具は、グラインダである。 According to a further aspect of the power tool according to the present invention, the power tool is a grinder.
　本形態によれば、動力工具としてのグラインダに対して、動力工具が発生する振動を効率よく低減することができる。 According to this embodiment, vibration generated by the power tool can be efficiently reduced with respect to the grinder as the power tool.
　本発明に係る動力工具の製造方法の好ましい形態によれば、動力工具は、先端工具が取り付けられる回転軸と、その回転軸と一体的に回転するボールバランサを備えている。当該ボールバランサは、複数のボールと、ボールを回転軸周りに回動可能に保持する所定の容積を有する回動領域が設けられたボール収納部材と、回動領域に充填された潤滑剤を有している。そして、動力工具が駆動したときの当該動力工具に生じる振動値が所定値以下となるように、潤滑剤の充填量を決定し、決定された充填量の潤滑剤を回動領域に充填してボールバランサを形成している。 According to a preferred embodiment of the method for manufacturing a power tool according to the present invention, the power tool includes a rotating shaft to which a tip tool is attached and a ball balancer that rotates integrally with the rotating shaft. The ball balancer includes a plurality of balls, a ball storage member provided with a rotation area having a predetermined volume for holding the balls so as to be rotatable around a rotation axis, and a lubricant filled in the rotation area. is doing. Then, the filling amount of the lubricant is determined so that the vibration value generated in the power tool when the power tool is driven is equal to or less than a predetermined value, and the determined filling amount of the lubricant is filled in the rotation region. A ball balancer is formed.
　本発明によれば、振動値が所定値以下となるように、潤滑剤の充填量を決定することができ、潤滑剤の充填量を適切に設定しつつ、動力工具に生じる振動を抑制できるボールバランサを備えた動力工具を製造することができる。 According to the present invention, it is possible to determine the amount of lubricant filling so that the vibration value is equal to or less than a predetermined value, and appropriately set the amount of lubricant filling while suppressing vibration generated in the power tool. A power tool equipped with a balancer can be manufactured.
　本発明に係る動力工具の製造方法の更なる形態によれば、潤滑剤の充填量は、回動領域の容積に対する充填率Ｘが、当該潤滑剤の粘度に対応する値μに対して、下記数式（２）を満たす量である。この「回動領域の容積」とは、回動領域におけるボールが回動可能な容積から、ボールの容積の合計を差し引いた容積である。 According to the further form of the manufacturing method of the power tool which concerns on this invention, the filling amount of a lubricant is the following with respect to the value (micro | micron | mu) with which the filling rate X with respect to the volume of a rotation area | region respond | corresponds to the viscosity of the said lubricant. This is the amount that satisfies the formula (2). The “volume of the rotation area” is a volume obtained by subtracting the total volume of the balls from the volume in which the balls can rotate in the rotation area.
数式（２）
Figure JPOXMLDOC01-appb-I000004
Formula (2)
Figure JPOXMLDOC01-appb-I000004
　本形態によれば、潤滑剤の粘度に応じて、充填率を設定することで、ボールを円滑に動作させることができるボールバランサが提供される。これにより、動力工具が発生する振動を効率よく低減することができるボールバランサを備えた動力工具を製造することができる。 According to this embodiment, it is possible to provide a ball balancer that can smoothly operate the ball by setting the filling rate according to the viscosity of the lubricant. Thereby, the power tool provided with the ball balancer which can reduce the vibration which a power tool generate | occur | produces efficiently can be manufactured.
　本発明に係る動力工具の製造方法の更なる形態によれば、潤滑剤は、粘度がＶＧ１００以下であり、潤滑剤の充填量は、回動領域の容積に対する充填量が２７％以下の量である。この「回動領域の容積」とは、回動領域におけるボールが回動可能な容積から、各ボールの容積の合計を差し引いた容積である。なお、ＶＧとは、ＩＳＯの粘度グレードを表す記号であり、ＶＧに続く数値はその中点動粘度を ｍｍ２／ｓ の単位で表したものである。 According to the further form of the manufacturing method of the power tool which concerns on this invention, the viscosity of a lubricant is VG100 or less, and the filling amount of a lubricant is an amount whose filling amount with respect to the volume of a rotation area | region is 27% or less. is there. The “volume of the rotation area” is a volume obtained by subtracting the total volume of each ball from the volume in which the ball in the rotation area can rotate. Note that VG is a symbol representing the ISO viscosity grade, and the numerical value following VG is the midpoint kinematic viscosity expressed in units of mm 2 / s.
　本形態によれば、潤滑剤の粘度と充填量を適切に設定することで、ボールを円滑に動作させることができるボールバランサが提供される。これにより、動力工具が発生する振動を効率よく低減することができるボールバランサを備えた動力工具を製造することができる。 According to this embodiment, a ball balancer capable of smoothly operating a ball by appropriately setting the viscosity and filling amount of the lubricant is provided. Thereby, the power tool provided with the ball balancer which can reduce the vibration which a power tool generate | occur | produces efficiently can be manufactured.
　本発明に係る動力工具の製造方法の更なる形態によれば、動力工具に生じる振動値が、手腕振動値で、２．５ｍ／ｓ２以下となるように、潤滑剤の充填量を決定している。 According to the further form of the manufacturing method of the power tool which concerns on this invention, the filling amount of a lubricant is determined so that the vibration value which arises in a power tool may be 2.5 m / s < 2 > or less in a hand-arm vibration value. ing.
　本形態によれば、動力工具に生じる振動値を手腕振動値で２．５ｍ／ｓ２以下となるように、潤滑剤の充填量を適切に決定することができる。なお、欧州連合議会が公布した欧州連合人体振動指令２００２／４４／ＥＣによると、２．５ｍ／ｓ２の日振動暴露対策値を規定している。すなわち、２．５ｍ／ｓ２の日振動暴露対策値を達成した時に手持ち式振動及び打撃機器、工具及びワークピースの使用者に手腕振動症候群に関係する症状の発現の可能性を低減することになると考えられる値である。この２．５ｍ／ｓ２の日振動暴露対策値は、アメリカ合衆国及び他の国の医療関係者、科学者及び政府機関、研究機関並びに業界で一般的に認められている。 According to this embodiment, the filling amount of the lubricant can be appropriately determined so that the vibration value generated in the power tool is 2.5 m / s 2 or less in terms of hand-arm vibration value. According to the European Union Human Body Vibration Directive 2002/44 / EC promulgated by the European Parliament, the daily vibration exposure countermeasure value of 2.5 m / s 2 is specified. That is, to reduce the possibility of symptoms related to hand-arm vibration syndrome to users of hand-held vibration and striking equipment, tools and workpieces when the daily vibration exposure countermeasure value of 2.5 m / s 2 is achieved. It is a value that is considered to be. This 2.5 m / s 2 daily vibration exposure control value is generally accepted by medical professionals, scientists and government agencies, research institutions and industries in the United States and other countries.
　本発明に係る動力工具の製造方法の更なる形態によれば、動力工具は、グラインダである。 According to the further form of the manufacturing method of the power tool which concerns on this invention, a power tool is a grinder.
　本形態によれば、動力工具としてのグラインダに対して、動力工具が発生する振動を効率よく低減することができる動力工具を製造することができる。 According to this embodiment, it is possible to manufacture a power tool that can efficiently reduce vibrations generated by the power tool with respect to a grinder as a power tool.
　本発明によれば、ボールが円滑に動作するためのボールバランサに関する技術を提供することができる。 According to the present invention, it is possible to provide a technique related to a ball balancer that allows a ball to operate smoothly.
本発明の実施形態に係るグラインダの全体構造を示す断面図である。It is sectional drawing which shows the whole grinder structure concerning embodiment of this invention. 図１におけるII－II線の断面図である。FIG. 2 is a cross-sectional view taken along line II-II in FIG. ボールバランサの平断面図である。It is a plane sectional view of a ball balancer. 図３におけるIV－IV線の断面図である。FIG. 4 is a sectional view taken along line IV-IV in FIG. 3. ボールバランサの潤滑油の充填率を決定するフローチャートである。It is a flowchart which determines the filling rate of the lubricating oil of a ball balancer. 潤滑油の充填率とグラインダの振動値の関係を示す図である。It is a figure which shows the relationship between the filling rate of lubricating oil, and the vibration value of a grinder.
　以下、本発明に実施形態につき、図１～図６を参照しつつ、詳細に説明する。本実施形態では、動力工具としてグラインダを例に挙げて説明する。このグラインダは、モータにより研削工具や研磨工具などの砥石や切断工具等の先端工具を回転させて、被加工材に対して研削や研磨および切断等を行う動力工具である。 Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. In the present embodiment, a grinder will be described as an example of a power tool. This grinder is a power tool that rotates a grinding tool such as a grinding tool or a polishing tool or a tip tool such as a cutting tool by a motor to perform grinding, polishing, cutting, or the like on a workpiece.
　図１、図２に示すように、グラインダ１は、メインハウジング１０とギアハウジング２０とリアカバー３０とホイールカバー４０を主体として構成されている。 1 and 2, the grinder 1 is mainly composed of a main housing 10, a gear housing 20, a rear cover 30, and a wheel cover 40.
　メインハウジング１０は、略円筒形状のハウジングであり、モータ１００を収容している。モータ１００の回転軸１０１は、ギアハウジング２０に向かって突出するように配置されている。 The main housing 10 is a substantially cylindrical housing and houses the motor 100. The rotation shaft 101 of the motor 100 is disposed so as to protrude toward the gear housing 20.
　ギアハウジング２０は、メインハウジング１０の一方側に設けられ、第１べベルギア２００、第２べベルギア２０１、スピンドル２０２、ベアリング２０３，２０４等を収容している。第１べベルギアは、モータ１００の回転軸１０１に外装されている。第２べベルギア２０１は、第１べベルギア２００と螺合するように配置されている。第２べベルギア２０１の中心部には、スピンドル２０２が配置されており、第２べベルギア２０１とスピンドル２０２は一体になって回転する。これにより、モータ１００の回転出力を回転軸１０１と直交するスピンドル２０２の軸周りの回転力に変換している。このスピンドル２０２は、２つのベアリング２０３，２０４に保持されている。 The gear housing 20 is provided on one side of the main housing 10 and houses the first bevel gear 200, the second bevel gear 201, the spindle 202, the bearings 203, 204, and the like. The first bevel gear is externally mounted on the rotating shaft 101 of the motor 100. The second bevel gear 201 is disposed so as to be screwed with the first bevel gear 200. A spindle 202 is disposed at the center of the second bevel gear 201, and the second bevel gear 201 and the spindle 202 rotate together. Thereby, the rotation output of the motor 100 is converted into a rotational force around the axis of the spindle 202 orthogonal to the rotation axis 101. The spindle 202 is held by two bearings 203 and 204.
　リアカバー３０は、メインハウジング１０のギアハウジング２０と反対側に設けられ、電源配線部３００を収容している。電源配線部３００には、外部の電源から電流を供給する電源コード３０１と、グラインダ１の駆動のＯＮ／ＯＦＦを切り替えるスイッチ３０２が設けられている。この電源配線部３００は、モータ１００に電気的に接続されている。 The rear cover 30 is provided on the opposite side of the main housing 10 from the gear housing 20 and accommodates the power supply wiring portion 300. The power supply wiring unit 300 is provided with a power supply cord 301 that supplies current from an external power supply and a switch 302 that switches ON / OFF of the drive of the grinder 1. The power supply wiring unit 300 is electrically connected to the motor 100.
　ホイールカバー４０は、ギアハウジング２０の外部に着脱可能に取り付けられた略半円形状の部品である。スピンドル２０２のギアハウジング２０の外側に突出する部分には、ボールバランサ４００が取り付けられている。さらに、スピンドル２０２の先端部には、スピンドル２０２に対して着脱可能なアウタフランジ４１がスピンドル２０２と螺合している。そして、ボールバランサ４００とアウタフランジ４１よって、砥石２が着脱可能に挟持されている。このスピンドル２０２に取り付けられた砥石２の外側を半周覆うようにホイールカバー４０が構成されている。これにより、ホイールカバー４０は、砥石２によって加工された被加工材の破片の飛散を抑制するとともに、回転する砥石２からユーザを保護している。この砥石２が本発明の「先端工具」に対応する実施構成例である。 The wheel cover 40 is a substantially semicircular part that is detachably attached to the outside of the gear housing 20. A ball balancer 400 is attached to a portion of the spindle 202 that protrudes outside the gear housing 20. Further, an outer flange 41 that can be attached to and detached from the spindle 202 is screwed to the spindle 202 at the tip of the spindle 202. The grindstone 2 is detachably held between the ball balancer 400 and the outer flange 41. The wheel cover 40 is configured so as to cover the outside of the grindstone 2 attached to the spindle 202 half a circumference. Thereby, the wheel cover 40 suppresses scattering of fragments of the workpiece processed by the grindstone 2 and protects the user from the rotating grindstone 2. This grindstone 2 is an implementation structural example corresponding to the "tip tool" of the present invention.
　次に、図３、図４を参照して、ボールバランサ４００について詳細に説明する。ボールバランサ４００は、バランサボディ４０１、ボール４０２、バランサカバー４０３を主体として構成されている。 Next, the ball balancer 400 will be described in detail with reference to FIGS. The ball balancer 400 is mainly composed of a balancer body 401, balls 402, and a balancer cover 403.
　バランサボディ４０１は、金属製の略円盤状の部材である。バランサボディ４０１の中心部には、スピンドル２０２が挿通される貫通孔４０４が形成されている。また、貫通孔４０４の周囲には、バランサボディ４０１の一面に開口した溝４０５が形成されている。ボール４０２は、金属製の球体であり、溝４０５内において８個のボール４０２が、溝４０５内を貫通孔４０４周りに移動可能に保持されている。バランサボディ４０１の一面には、溝４０５の開口を塞ぐようにバランサカバー４０３が配置されている。なお、溝４０５内には、ボール４０２の移動を円滑にするための図示しない潤滑油が封入されている。このバランサボディ４０１とバランサカバー４０３が、本発明の「ボール収納部材」に対応する実施構成例である。また、溝４０５が、本発明の「回動領域」に対応する実施構成例である。 The balancer body 401 is a metal substantially disk-shaped member. A through hole 404 through which the spindle 202 is inserted is formed at the center of the balancer body 401. In addition, a groove 405 opened on one surface of the balancer body 401 is formed around the through hole 404. The ball 402 is a metal sphere, and eight balls 402 are held in the groove 405 so as to be movable around the through hole 404 in the groove 405. A balancer cover 403 is disposed on one surface of the balancer body 401 so as to close the opening of the groove 405. Note that lubricating oil (not shown) for smooth movement of the ball 402 is enclosed in the groove 405. The balancer body 401 and the balancer cover 403 are an implementation configuration example corresponding to the “ball storage member” of the present invention. Further, the groove 405 is an implementation configuration example corresponding to the “rotation region” of the present invention.
　以上の通り構成されたグラインダ１は、スイッチ３０２が操作されることによって、外部の電源から電気配線部３００を介して、モータ１００に電力が供給される。これにより、モータ１００が回転駆動し、回転軸１０１に取り付けられた第１べベルギア２００が回転する。第１べベルギア２００と第２べベルギア２０１が螺合して回転することで、モータ１００の回転出力をスピンドル２０２周りの回転力に変換して、第２べベルギア２０１と一体となって回転するスピンドル２０２に装着された砥石２を回転させる。回転する砥石２を被加工材に押し当てることで被加工材を加工することができる。 The grinder 1 configured as described above is supplied with electric power from the external power supply to the motor 100 via the electric wiring unit 300 when the switch 302 is operated. As a result, the motor 100 is driven to rotate, and the first bevel gear 200 attached to the rotating shaft 101 rotates. When the first bevel gear 200 and the second bevel gear 201 are screwed together and rotated, the rotation output of the motor 100 is converted into a rotational force around the spindle 202 and rotated integrally with the second bevel gear 201. The grindstone 2 mounted on the spindle 202 is rotated. The workpiece can be processed by pressing the rotating grindstone 2 against the workpiece.
　グラインダ１が駆動するとグラインダ１には振動が生じる。スピンドル２０２と一体となって回転する砥石２等の重心位置とスピンドル２０２の回転軸との離隔距離（偏心距離）が大きい時ほどグラインダ１に生じる振動が大きい。このとき、スピンドル２０２に取り付けられたボールバランサ４００が、スピンドル２０２と一体となって回転する。これにより、複数のボール４０２が、スピンドル２０２と一体となって回転する砥石２等の重心位置とスピンドル２０２の回転軸との離隔距離を縮めるように、溝４０５内を回動する。すなわち、本実施形態においては、ボールバランサ４００によってグラインダ１に生じる振動を低減している。 ¡When the grinder 1 is driven, the grinder 1 vibrates. The greater the distance (eccentric distance) between the position of the center of gravity of the grindstone 2 and the like that rotates integrally with the spindle 202 and the rotation axis of the spindle 202, the greater the vibration generated in the grinder 1. At this time, the ball balancer 400 attached to the spindle 202 rotates integrally with the spindle 202. As a result, the plurality of balls 402 rotate in the groove 405 so as to reduce the distance between the center of gravity of the grindstone 2 and the like rotating together with the spindle 202 and the rotation axis of the spindle 202. That is, in the present embodiment, vibration generated in the grinder 1 by the ball balancer 400 is reduced.
　次にグラインダ１の製造方法について説明する。グラインダ１の製造方法は公知の製造方法であるため、ボールバランサ４００の製造方法について説明する。 Next, a method for manufacturing the grinder 1 will be described. Since the manufacturing method of the grinder 1 is a well-known manufacturing method, the manufacturing method of the ball balancer 400 is demonstrated.
　ボールバランサ４００の溝４０５内が潤滑油で充満されていると、潤滑油の流体抵抗により、ボール４０２の移動を妨げてしまう。そのため、溝４０５内に封入する潤滑油の量を適切に設定する必要がある。本実施形態の製造方法においては、ボール４０２を円滑に回動させることによって、グラインダ１が駆動したときの当該グラインダ１に生じる振動値が所定値以下となるように、潤滑油の充填量を決定している。そして、決定された充填量の潤滑油を回動領域に充填してボールバランサ４００を形成している。 If the groove 405 of the ball balancer 400 is filled with the lubricating oil, the movement of the ball 402 is hindered by the fluid resistance of the lubricating oil. Therefore, it is necessary to appropriately set the amount of lubricating oil sealed in the groove 405. In the manufacturing method of the present embodiment, the amount of lubricating oil charged is determined so that the vibration value generated in the grinder 1 when the grinder 1 is driven is less than or equal to a predetermined value by smoothly rotating the ball 402. is doing. The ball balancer 400 is formed by filling the rotation region with the determined amount of lubricating oil.
　この充填量は、潤滑油の粘度と、潤滑油の充填率の関係から決定される。充填率は、溝４０５においてボール４０２が回動可能な領域の容積から８個のボール４０２の容積の合計を差し引いた容積に対する潤滑油の充填量として算出される。この充填率について、出願人は、予め行った実験に基づき潤滑油の充填率を設定している。その実験について、図５を参照して説明する。図５において、ステップ１（Ｓ１）は「ボールバランサ４００の寸法を設定」するステップである。ステップ２（Ｓ２）は「充填する潤滑油を設定」するステップである。ステップ３（Ｓ３）は「充填率と振動値の関係を測定」するステップである。ステップ４（Ｓ４）は「潤滑油の充填率を決定」するステップである。 This filling amount is determined from the relationship between the viscosity of the lubricating oil and the filling rate of the lubricating oil. The filling rate is calculated as the filling amount of the lubricating oil with respect to the volume obtained by subtracting the sum of the volumes of the eight balls 402 from the volume of the region in which the balls 402 can rotate in the groove 405. Regarding this filling rate, the applicant sets the filling rate of the lubricating oil based on experiments conducted in advance. The experiment will be described with reference to FIG. In FIG. 5, step 1 (S1) is a step of “setting the dimensions of the ball balancer 400”. Step 2 (S2) is a step of “setting lubricating oil to be filled”. Step 3 (S3) is a step of “measuring the relationship between the filling rate and the vibration value”. Step 4 (S4) is a step of “determining the filling rate of the lubricating oil”.
　最初に、ボールバランサ４００の各寸法を設定する（Ｓ１）。図３、図４におけるボールバランサ４００の各寸法は、次の通りである。溝４０５の内径Ｒ１は３６ｍｍで、外径Ｒ２は５５ｍｍであり、深さＤは９．８ｍｍである。また、ボール４０２の直径は８．７３ｍｍである。 First, each dimension of the ball balancer 400 is set (S1). The dimensions of the ball balancer 400 in FIGS. 3 and 4 are as follows. The inner diameter R1 of the groove 405 is 36 mm, the outer diameter R2 is 55 mm, and the depth D is 9.8 mm. The diameter of the ball 402 is 8.73 mm.
　次に、溝４０５に充填する潤滑油を設定する（Ｓ２）。ここでは、潤滑油としてシェル（登録商標）テラスオイルを使用している。 Next, the lubricating oil filled in the groove 405 is set (S2). Here, Shell (registered trademark) terrace oil is used as the lubricating oil.
　そして、粘度の異なる３種類の潤滑油（ＶＧ３２、ＶＧ６８、ＶＧ１００）について、充填量を変えてグラインダ１を駆動させた。グラインダ１の駆動によってグラインダ１に生じる加速度を測定した。これにより、充填率と振動値の関係を測定した（Ｓ３）。なお、ＶＧとは、ＩＳＯの粘度グレードを表す記号であり、ＶＧに続く数値はその中点動粘度を ｍｍ２／ｓ の単位で表したものである。 And about three types of lubricating oil (VG32, VG68, VG100) from which a viscosity differs, the filling amount was changed and the grinder 1 was driven. The acceleration generated in the grinder 1 by driving the grinder 1 was measured. Thereby, the relationship between the filling rate and the vibration value was measured (S3). Note that VG is a symbol representing the ISO viscosity grade, and the numerical value following VG is the midpoint kinematic viscosity expressed in units of mm 2 / s.
　なお、加速度の測定は、モータ１００の回転軸１０１が水平方向と一致し、スピンドル２０２が鉛直方向と一致するようにグラインダ１を回転軸１０１の軸方向２点で保持した状態で、３軸加速度ピックアップにより３軸それぞれの加速度を測定した。そして、測定した加速度について、適宜フィルタ処理を施し、３軸方向の加速度を合成した値を振動値として設定した。そして、潤滑油の充填率と振動値の関係を求めた。 The acceleration is measured in a state where the grinder 1 is held at two points in the axial direction of the rotary shaft 101 so that the rotary shaft 101 of the motor 100 matches the horizontal direction and the spindle 202 matches the vertical direction. The acceleration of each of the three axes was measured with a pickup. Then, the measured acceleration was appropriately filtered, and a value obtained by synthesizing the accelerations in the three axis directions was set as a vibration value. The relationship between the filling rate of the lubricating oil and the vibration value was obtained.
　以上に基づき、潤滑油の充填率を決定する（Ｓ４）。図６は、Ｓ３における実験結果である潤滑油の充填率と振動値の関係を示すグラフである。図６に示されるグラフの縦軸は、振動値を表しており、３軸方向の加速度を合成した値である。振動値の単位は（ｍ／ｓ２）である。また、図６に示されるグラフの横軸は、潤滑油の充填率を表しており、充填率の単位は（％）である。このグラフによると、潤滑油は、粘度がＶＧ１００以下であって、振動値２．５ｍ／ｓ２以下となる充填率である２７％以下であることが好ましい。 Based on the above, the filling rate of the lubricating oil is determined (S4). FIG. 6 is a graph showing the relationship between the filling rate of the lubricating oil and the vibration value as an experimental result in S3. The vertical axis of the graph shown in FIG. 6 represents a vibration value, and is a value obtained by synthesizing accelerations in three axis directions. The unit of vibration value is (m / s 2 ). Further, the horizontal axis of the graph shown in FIG. 6 represents the filling rate of the lubricating oil, and the unit of the filling rate is (%). According to this graph, it is preferable that the lubricating oil has a viscosity of VG100 or less and a filling rate of 27% or less that gives a vibration value of 2.5 m / s 2 or less.
　また一方で、出願人は、潤滑油の充填率Ｘと振動値Ｙの関係が下記数式（３）の２次関数で近似できることを知見した。 On the other hand, the applicant has found that the relationship between the filling rate X of the lubricating oil and the vibration value Y can be approximated by a quadratic function of the following formula (3).
数式（３）
Figure JPOXMLDOC01-appb-I000005
Formula (3)
Figure JPOXMLDOC01-appb-I000005
　ここで、ａ，ｂは、封入する潤滑油の粘度によって決まる係数でａ＝４．５×１０－６μ，ｂ＝３０－０．５μとなる。また、ｃは、ボール４０２の真円度や表面粗さによって決まる値である。一般的な加工である場合、ｃ＝１．５程度である。ここでは、粘度に対応するμは、ＩＳＯの粘度グレードを表す記号ＶＧの後に続く値を用いた。 Here, a and b are coefficients determined by the viscosity of the lubricating oil to be enclosed, and a = 4.5 × 10 −6 μ and b = 30−0.5 μ. Further, c is a value determined by the roundness and surface roughness of the ball 402. In the case of general processing, c = about 1.5. Here, as the μ corresponding to the viscosity, the value following the symbol VG representing the ISO viscosity grade was used.
　振動値Ｙが所定の振動値Ｆよりも小さくなる条件を求めると、下記数式（４）の通りとなる。 When the condition that the vibration value Y is smaller than the predetermined vibration value F is obtained, the following equation (4) is obtained.
数式（４）
Figure JPOXMLDOC01-appb-I000006
Formula (4)
Figure JPOXMLDOC01-appb-I000006
　ここで、所定の振動値Ｆを２．５であるとすると、下記数式（５）の通りとなる。この振動値は、欧州連合人体振動指令２００２／４４／ＥＣにおいて規定されている日振動暴露対策値２．５ｍ／ｓ２に対応している。 Here, when the predetermined vibration value F is 2.5, the following formula (5) is obtained. This vibration value corresponds to the daily vibration exposure countermeasure value of 2.5 m / s 2 stipulated in the European Union Human Body Vibration Directive 2002/44 / EC.
数式（５）
Figure JPOXMLDOC01-appb-I000007
Formula (5)
Figure JPOXMLDOC01-appb-I000007
　以上の知見に基づき、所定の振動値Ｆを設定し、数式（４）を満たすように粘度に応じた潤滑油の充填率を決定することができる。一方、所定の振動値Ｆを２．５と設定して、数式（５）を満たすように粘度に応じた潤滑油の充填率を決定してしてもよい。 Based on the above knowledge, a predetermined vibration value F is set, and the filling rate of the lubricating oil according to the viscosity can be determined so as to satisfy the formula (4). On the other hand, the predetermined vibration value F may be set to 2.5, and the filling rate of the lubricating oil according to the viscosity may be determined so as to satisfy Formula (5).
　以上によって決定された充填率に対応する充填量の潤滑油を溝４０５内に充填し、ボールバランサ４００を形成している。その後、ボールバランサ４００をスピンドル２０２に一体的に取り付けることで、グラインダ１を形成している。 The ball balancer 400 is formed by filling the groove 405 with a filling amount of lubricating oil corresponding to the filling rate determined as described above. Then, the grinder 1 is formed by attaching the ball balancer 400 to the spindle 202 integrally.
　以上の各設定値等は、実施構成例であり、本願発明の内容を限定するものではない。また、本実施形態では、充填率を、溝４０５においてボール４０２が回動可能な領域の容積からボール４０２の容積（各ボール４０２の容積の合計）を差し引いた容積に対する潤滑油の充填量と定義している。しかしながら、充填率を、溝４０５の容積に対する潤滑油の充填量と定義して、充填率と振動値の関係を算出して、潤滑油の充填量を決定してもよい。 The above set values and the like are examples of implementation configurations and do not limit the contents of the present invention. Further, in the present embodiment, the filling rate is defined as the filling amount of the lubricating oil with respect to the volume obtained by subtracting the volume of the ball 402 (the total volume of each ball 402) from the volume of the region in which the ball 402 can rotate in the groove 405. is doing. However, the filling rate may be defined as the filling amount of the lubricating oil with respect to the volume of the groove 405, and the relationship between the filling rate and the vibration value may be calculated to determine the filling amount of the lubricating oil.
　以上の通り、潤滑油の粘度に応じて潤滑油の充填率を設定することで、ボール４０２を円滑に動作させることができる。これにより、ボール４０２が円滑に動作するボールバランサ４００を備えたグラインダ１を形成することができる。その結果、グラインダ１が発生する振動を効率よく低減することができる。さらに、本実施形態においては、溝４０５に潤滑油を充満させる場合に比べて潤滑油の充填量を少なくすることができ、グラインダ１をコストダウンすることができる。 As described above, the ball 402 can be operated smoothly by setting the filling rate of the lubricating oil according to the viscosity of the lubricating oil. Thereby, the grinder 1 provided with the ball balancer 400 with which the ball 402 operates smoothly can be formed. As a result, the vibration generated by the grinder 1 can be efficiently reduced. Furthermore, in this embodiment, the filling amount of lubricating oil can be reduced compared with the case where the groove 405 is filled with lubricating oil, and the grinder 1 can be reduced in cost.
　以上においては、潤滑油としてシェル（登録商標）テラスオイルを使用しているが、他の潤滑剤を用いても、上記の通り、その潤滑剤の粘度に応じて充填率を設定することが可能である。 In the above, Shell (registered trademark) terrace oil is used as the lubricating oil. However, as described above, the filling rate can be set according to the viscosity of the lubricant even when other lubricants are used. It is.
　以上においては、所定の振動値Ｆとして、２．５を適用している。振動値である２．５は、欧州連合人体振動指令２００２／４４／ＥＣにおいて規定されている振動値２．５ｍ／ｓ２に対応している。しかしながら、所定の振動値Ｆは要求される性能に応じて、適宜設定することが可能である。なお、振動値Ｆは、振動値に対応する値を用いてもよい。また振動値Ｆは、振動値そのものの値を用いてもよく、また、振動値を無次元化した値を用いてもよい。 In the above, 2.5 is applied as the predetermined vibration value F. The vibration value of 2.5 corresponds to the vibration value of 2.5 m / s 2 defined in the European Union Human Body Vibration Directive 2002/44 / EC. However, the predetermined vibration value F can be appropriately set according to the required performance. The vibration value F may be a value corresponding to the vibration value. The vibration value F may be the vibration value itself, or may be a value obtained by making the vibration value dimensionless.
　また、以上においては、粘度に対応する値μとして、ＩＳＯの粘度グレードを表す記号ＶＧの後に続く値を用いているが、粘度そのものの値を用いてもよい。また、粘度を無次元化した値を用いてもよい。 In the above description, the value μ following the symbol VG representing the ISO viscosity grade is used as the value μ corresponding to the viscosity, but the value of the viscosity itself may be used. A value obtained by making the viscosity dimensionless may be used.
　以上においては、動力工具としてグラインダを例に説明したが、これには限られない。例えば、モータで駆動するハンマドリルや、エンジンで駆動する刈払機等に本発明を適用することも可能である。 In the above description, the grinder is taken as an example of the power tool, but it is not limited to this. For example, the present invention can be applied to a hammer drill driven by a motor, a brush cutter driven by an engine, or the like.
　上記発明の趣旨に鑑み、本発明に係る動力工具は、下記の態様が構成可能である。
（態様１）
「先端工具が取り付けられる回転軸と、
　前記回転軸と一体的に回転するとともに、複数のボールと、当該ボールを前記回転軸周りに回動可能に保持する所定の容積を有する回動領域が設けられたボール収納部材と、前記回動領域に充填された潤滑剤と、を有するボールバランサを備えた動力工具であって、
　前記潤滑剤の充填量は、前記ボールを円滑に回動させることによって、前記動力工具が駆動したときの当該動力工具に生じる振動値を低減させる充填量であって、前記回動領域の容積に対する充填率Ｘが、前記潤滑剤の粘度によって定まる係数ａおよびｂと、ボールの真円度と表面粗さによって定まる係数ｃと、前記潤滑剤の粘度に対応する値μに対して、振動値が所定の振動値Ｆ以下となる下記数式（６）を満たす充填率に対応する量であることを特徴とする動力工具。」 In view of the gist of the present invention, the power tool according to the present invention can be configured in the following manner.
(Aspect 1)
“Rotating shaft to which the tip tool is attached,
A ball storage member provided with a plurality of balls and a rotation area having a predetermined volume for rotatably holding the balls around the rotation shaft while rotating integrally with the rotation shaft; A power tool comprising a ball balancer having a lubricant filled in the region,
The filling amount of the lubricant is a filling amount that reduces a vibration value generated in the power tool when the power tool is driven by smoothly rotating the ball, and is based on the volume of the rotation region. For the filling factor X, coefficients a and b determined by the viscosity of the lubricant, coefficient c determined by the roundness and surface roughness of the ball, and a value μ corresponding to the viscosity of the lubricant, the vibration value is A power tool characterized by an amount corresponding to a filling rate satisfying the following mathematical formula (6) that is equal to or less than a predetermined vibration value F. "
数式（６）
Figure JPOXMLDOC01-appb-I000008
Formula (6)
Figure JPOXMLDOC01-appb-I000008
　また、上記発明の趣旨に鑑み、本発明に係る動力工具の製造方法は、下記の態様が構成可能である。
（態様２）
「先端工具が取り付けられる回転軸と、
　前記回転軸と一体的に回転するとともに、複数のボールと、当該ボールを前記回転軸周りに回動可能に保持する所定の容積を有する回動領域が設けられたボール収納部材と、前記回動領域に充填された潤滑剤と、を有するボールバランサを備えた動力工具の製造方法であって、
　前記ボールを円滑に回動させることによって、前記動力工具が駆動したときの当該動力工具に生じる振動値が所定値以下となるように、前記潤滑剤の充填量を、前記潤滑剤の前記回動領域の容積に対する充填率Ｘが、前記潤滑剤の粘度によって定まる係数ａおよびｂと、ボールの真円度と表面粗さによって定まる係数ｃと、前記潤滑剤の粘度に対応する値μに対して、振動値が所定の振動値Ｆ以下となる下記数式（７）を満たす充填率に対応する量となるように決定し、
　決定された前記充填量の前記潤滑剤を前記回動領域に充填して前記ボールバランサを形成することを特徴とする動力工具の製造方法。」 Moreover, in view of the meaning of the said invention, the following aspect can be comprised in the manufacturing method of the power tool which concerns on this invention.
(Aspect 2)
“Rotating shaft to which the tip tool is attached,
A ball housing member that rotates integrally with the rotation shaft and that has a plurality of balls and a rotation area having a predetermined volume for rotatably holding the balls around the rotation shaft; and the rotation A method of manufacturing a power tool comprising a ball balancer having a lubricant filled in a region,
By smoothly rotating the ball, the amount of the lubricant filled is adjusted so that the vibration value generated in the power tool when the power tool is driven is less than or equal to a predetermined value. The filling factor X with respect to the volume of the region is based on the coefficients a and b determined by the viscosity of the lubricant, the coefficient c determined by the roundness and surface roughness of the ball, and the value μ corresponding to the viscosity of the lubricant. The vibration value is determined to be an amount corresponding to the filling rate that satisfies the following mathematical formula (7) that is equal to or less than the predetermined vibration value F,
A method of manufacturing a power tool, wherein the ball balancer is formed by filling the rotation region with the determined amount of the lubricant. "
数式（７）
Figure JPOXMLDOC01-appb-I000009
Formula (7)
Figure JPOXMLDOC01-appb-I000009
１　グラインダ
２　砥石
１０　メインハウジング
２０　ギアハウジング
３０　リアカバー
４０　ホイールカバー
４１　アウタフランジ
１００　モータ
１０１　回転軸
２００　第１べベルギア
２０１　第２べベルギア
３００　電源配線部
３０１　電源コード
３０２　スイッチ
４００　ボールバランサ
４０１　バランサボディ
４０２　ボール
４０３　バランサカバー
４０４　貫通孔
４０５　溝 1 grinder 2 grindstone 10 main housing 20 gear housing 30 rear cover 40 wheel cover 41 outer flange 100 motor 101 rotating shaft 200 first bevel gear 201 second bevel gear 300 power wiring section 301 power cord 302 switch 400 ball balancer 401 balancer body 402 ball 403 Balancer cover 404 Through hole 405 Groove

Claims (9)

  1. 　先端工具が取り付けられる回転軸と、
    　前記回転軸と一体的に回転するとともに、複数のボールと、当該ボールを前記回転軸周りに回動可能に保持する所定の容積を有する回動領域が設けられたボール収納部材と、前記回動領域に充填された潤滑剤と、を有するボールバランサを備えた動力工具であって、
    　前記潤滑剤の充填量は、前記ボールを円滑に回動させることによって、前記動力工具が駆動したときの当該動力工具に生じる振動値を低減させる充填量であることを特徴とする動力工具。     A rotating shaft to which the tip tool is attached;
    A ball housing member that rotates integrally with the rotation shaft and that has a plurality of balls and a rotation area having a predetermined volume for rotatably holding the balls around the rotation shaft; and the rotation A power tool comprising a ball balancer having a lubricant filled in the region,
    The power tool is characterized in that the filling amount of the lubricant is a filling amount that reduces a vibration value generated in the power tool when the power tool is driven by smoothly rotating the ball.
  2. 　請求項１に記載の動力工具であって、
    　前記潤滑剤の充填量は、前記回動領域の容積に対する充填率Ｘが、当該潤滑剤の粘度に対応する値μに対して、下記数式（１）を満たす充填率に対応する量であることを特徴とする動力工具。
    数式（１）
    Figure JPOXMLDOC01-appb-I000001
    The power tool according to claim 1,
    The filling amount of the lubricant is an amount corresponding to the filling rate that satisfies the following mathematical formula (1) with respect to the value μ corresponding to the viscosity of the lubricant, with respect to the filling rate X with respect to the volume of the rotating region. Power tool characterized by
    Formula (1)
    Figure JPOXMLDOC01-appb-I000001
  3. 　請求項１に記載の動力工具であって、
    　前記潤滑剤は、粘度がＶＧ１００以下であり、かつ当該潤滑剤の充填量は、前記回動領域の容積に対する充填率が２７％以下となる量であることを特徴とする動力工具。     The power tool according to claim 1,
    The power tool according to claim 1, wherein the lubricant has a viscosity of VG100 or less, and a filling amount of the lubricant is an amount such that a filling rate with respect to a volume of the rotating region is 27% or less.
  4. 　請求項１～３のいずれか１項に記載の動力工具であって、
    　前記動力工具は、グラインダであることを特徴とする動力工具。     The power tool according to any one of claims 1 to 3,
    The power tool is a grinder.
  5. 　先端工具が取り付けられる回転軸と、
    　前記回転軸と一体的に回転するとともに、複数のボールと、当該ボールを前記回転軸周りに回動可能に保持する所定の容積を有する回動領域が設けられたボール収納部材と、前記回動領域に充填された潤滑剤と、を有するボールバランサを備えた動力工具の製造方法であって、
    　前記ボールを円滑に回動させることによって、前記動力工具が駆動したときの当該動力工具に生じる振動値が所定値以下となるように、前記潤滑剤の充填量を決定し、
    　決定された前記充填量の前記潤滑剤を前記回動領域に充填して前記ボールバランサを形成することを特徴とする動力工具の製造方法。     A rotating shaft to which the tip tool is attached;
    A ball housing member that rotates integrally with the rotation shaft and that has a plurality of balls and a rotation area having a predetermined volume for rotatably holding the balls around the rotation shaft; and the rotation A method of manufacturing a power tool comprising a ball balancer having a lubricant filled in a region,
    By smoothly rotating the ball, the amount of the lubricant charged is determined so that a vibration value generated in the power tool when the power tool is driven is a predetermined value or less,
    A method of manufacturing a power tool, wherein the ball balancer is formed by filling the rotation region with the determined amount of the lubricant.
  6. 　請求項５に記載の動力工具の製造方法であって、
    　前記充填量は、前記潤滑剤の前記回動領域の容積に対する充填率Ｘが、当該潤滑剤の粘度に対応する値μに対して、下記数式（２）を満たす充填率に対応する量であることを特徴とする動力工具の製造方法。
    数式（２）
    Figure JPOXMLDOC01-appb-I000002
    It is a manufacturing method of the power tool according to claim 5,
    The filling amount is an amount corresponding to a filling rate where the filling rate X with respect to the volume of the rotation region of the lubricant satisfies the following mathematical formula (2) with respect to a value μ corresponding to the viscosity of the lubricant. A method for manufacturing a power tool.
    Formula (2)
    Figure JPOXMLDOC01-appb-I000002
  7. 　請求項５に記載の動力工具の製造方法であって、
    　前記潤滑剤は、粘度がＶＧ１００以下であり、
    　前記充填量は、前記回動領域の容積に対する充填率が２７％以下となる量であることを特徴とする動力工具の製造方法。     It is a manufacturing method of the power tool according to claim 5,
    The lubricant has a viscosity of VG100 or less,
    The method of manufacturing a power tool, wherein the filling amount is an amount such that a filling rate with respect to the volume of the rotating region is 27% or less.
  8. 　請求項５～７のいずれか１項に記載の動力工具の製造方法であって、
    　前記振動値は、手腕振動値であって、
    　前記所定値は、２．５ｍ／ｓ２であることを特徴とする動力工具の製造方法。     A method of manufacturing a power tool according to any one of claims 5 to 7,
    The vibration value is a hand-arm vibration value,
    The method for manufacturing a power tool, wherein the predetermined value is 2.5 m / s 2 .
  9. 　請求項５～８のいずれか１項に記載の動力工具の製造方法であって、
    　前記動力工具は、グラインダであることを特徴とする動力工具の製造方法。     A method for manufacturing a power tool according to any one of claims 5 to 8,
    The method of manufacturing a power tool, wherein the power tool is a grinder.
PCT/JP2012/075556 2011-10-04 2012-10-02 Power tool, and power tool manufacturing method WO2013051580A1 (en)

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JP6634248B2 (en) 2015-09-10 2020-01-22 株式会社マキタ Grinders and covers
JP6632840B2 (en) 2015-09-10 2020-01-22 株式会社マキタ Grinder
JP6667236B2 (en) 2015-09-10 2020-03-18 株式会社マキタ Grinders, covers and cover sets
JP6571463B2 (en) 2015-09-10 2019-09-04 株式会社マキタ Grinder and cover
DE112016004315T5 (en) 2015-09-25 2018-08-23 Makita Corporation sharpener
CN107538439B (en) * 2016-06-29 2023-09-12 苏州宝时得电动工具有限公司 Vibration reduction system and method for swinging machine and swinging machine with vibration reduction system
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