JP5252589B2

JP5252589B2 - Electric screwdriver with tilt detection function and screw tightening method with electric screwdriver

Info

Publication number: JP5252589B2
Application number: JP2010061014A
Authority: JP
Inventors: 侑山本
Original assignee: NEC Infrontia Corp
Current assignee: NEC Platforms Ltd
Priority date: 2010-03-17
Filing date: 2010-03-17
Publication date: 2013-07-31
Anticipated expiration: 2030-03-17
Also published as: JP2011194483A

Description

本発明は、傾き検出機能付き電動ドライバ及び電動ドライバによるネジ締め付け方法に関する。 The present invention relates to an electric driver with an inclination detection function and a screw tightening method using the electric driver.

電動ドライバを用いて、ネジ穴の設けられた対象物にネジ（雄ネジ）を締め付ける際には、ドライバビット（単に、ビットと称されることもある。）の軸がネジ締め面に垂直でないときは、ネジのネジ山や対象物のネジ穴を損傷し、あるいはドライバビットの先端の磨耗を早めたりする。ネジ締め面とは、ネジ穴の開口が設けられた対象物の表面領域であって、そのネジ穴の開口縁を含む領域の平面を指し、そのネジ穴の軸と直交する。ドライバビットは磁化されており、ドライバビットにネジの頭を吸着することにより、ドライバビットの先端はネジの頭の穴に嵌り、ネジはドライバビットに同軸に取り付けられる。 When an electric screwdriver is used to tighten a screw (male screw) to an object provided with a screw hole, the axis of the driver bit (sometimes simply referred to as a bit) is not perpendicular to the screw tightening surface. Sometimes it damages the thread of the screw or the screw hole of the object, or accelerates the wear of the tip of the driver bit. The screw tightening surface is a surface area of an object provided with an opening of a screw hole, and refers to a plane of an area including an opening edge of the screw hole, and is orthogonal to the axis of the screw hole. The driver bit is magnetized, and by adsorbing the screw head to the driver bit, the tip of the driver bit is fitted into the hole of the screw head, and the screw is coaxially attached to the driver bit.

ネジ締め面を水平に設定したときにおけるドライバビットの軸の垂直からの傾きが所定角度を超えたときには、電動ドライバのモータの駆動回路を遮断する「垂直検知機能付き電動ドライバ」なる発明が特許文献１に開示されている。特許文献１の技術では、電動ドライバ本体に可動導体を吊るし、電動ドライバ本体が所定角度を超えて傾くと、可動導体と導体受け部との接触が遮断する構造を採用している。そして、特許文献１の電動ドライバの構造では、モータの駆動回路にその接触部を電気的に直列に配置することにより、ドライバビットの軸が所定角度を超えて傾いたときに、電動ドライバのモータの駆動回路が遮断され、モータの回転が自動的に停止する。 An invention called “electric driver with vertical detection function” that shuts off the drive circuit of the motor of the electric driver when the inclination from the vertical of the axis of the driver bit when the screw tightening surface is set horizontally exceeds a predetermined angle is disclosed in Patent Literature 1 is disclosed. The technique of Patent Document 1 employs a structure in which a movable conductor is suspended from an electric driver main body, and when the electric driver main body is tilted beyond a predetermined angle, contact between the movable conductor and the conductor receiving portion is interrupted. And in the structure of the electric driver of patent document 1, when the axis | shaft of a driver bit inclines beyond a predetermined angle by arrange | positioning the contact part electrically in series with the drive circuit of a motor, the motor of an electric driver The drive circuit of the motor is cut off and the rotation of the motor is automatically stopped.

特許文献２には、対象物が床又は天井であるときに、ドライバビットをネジ締め面に垂直に設定することを容易にする「センサ付き電動ドライバ」なる考案が開示されている。この特許文献２の技術では、水平姿勢指示器を電動ドライバの本体に備え、ドライバビットの向きが垂直であることを目視より認識することにより、ドライバビットの軸とネジ締め面の法線とのなす角度を一定値以内に保持できるようにしている。 Patent Document 2 discloses a device called “electric driver with sensor” that facilitates setting a driver bit perpendicular to a screw tightening surface when an object is a floor or a ceiling. In the technique of Patent Document 2, a horizontal posture indicator is provided in the main body of the electric driver, and by visually recognizing that the direction of the driver bit is vertical, the axis of the driver bit and the normal of the screw tightening surface are The formed angle can be kept within a certain value.

特開２００２−３６１３６号公報JP 2002-36136 A 実開平４−１０４５１４号公報Japanese Utility Model Publication No. 4-104514

特許文献１に記載された垂直検知機能付き電動ドライバは、ネジ締め面を水平に設定したときにおけるドライバビットの軸がネジ締め面の法線（ネジ締め面に対し垂直な線）から所定角度を超えて傾いたときには、電動ドライバのモータの回転を停止できる。しかしながら、特許文献１に記載された垂直検知機能付き電動ドライバは、ネジ締め面が水平に設定できないときは、使用できない。 In the electric driver with a vertical detection function described in Patent Document 1, when the screw tightening surface is set horizontally, the axis of the driver bit has a predetermined angle from the normal line of the screw tightening surface (a line perpendicular to the screw tightening surface). When tilted beyond this, the rotation of the motor of the electric driver can be stopped. However, the electric driver with a vertical detection function described in Patent Document 1 cannot be used when the screw tightening surface cannot be set horizontally.

特許文献２に記載されたセンサ付き電動ドライバは、ネジ締め面が床や天井等という水平面であるときに、ドライバビットの軸とネジ締め面の法線とのなす角度を一定値以内に保持できる。しかしながら、特許文献２に記載されたセンサ付き電動ドライバは、水平姿勢指示器を目視より認識することにより、ドライバビットの向きが垂直であることを判定できるようにしているから、ネジ締め作業中は注意力を継続的に維持し続けなければ、ドライバビットの軸とネジ締め面の法線とのなす角度を一定値以内に保持できない。 The electric driver with a sensor described in Patent Document 2 can keep the angle formed by the axis of the driver bit and the normal of the screw tightening surface within a certain value when the screw tightening surface is a horizontal surface such as a floor or a ceiling. However, since the electric driver with a sensor described in Patent Document 2 recognizes the horizontal posture indicator by visual observation so that it can be determined that the direction of the driver bit is vertical, during the screw tightening operation Unless the attention is continuously maintained, the angle formed by the axis of the driver bit and the normal of the screw fastening surface cannot be maintained within a certain value.

そこで、本発明は、上記課題を解決し、ネジ締め面が水平でなくても、ネジ締め面の法線とドライバビットの軸が同一であることを判定でき、またネジ締め作業者に注意力の維持を求めなくても、ドライバビットの軸とネジ締め面の法線とのなす角度が所定値以内であるときだけにモータの回転を可能にする傾き検出機能付き電動ドライバ及び電動ドライバによるネジ締め付け方法を提供することを目的とする。 Therefore, the present invention solves the above-mentioned problem, and even if the screw tightening surface is not horizontal, it can be determined that the normal of the screw tightening surface and the axis of the driver bit are the same, and attention is paid to the screw tightening operator. Even if the maintenance of the screw is not required, the screwdriver with the tilt detection function and the screwdriver can be used only when the angle between the axis of the driver bit and the normal of the screw fastening surface is within a predetermined value. An object is to provide a tightening method.

前述の課題を解決するために本発明は次の手段を提供する。
（１）本発明の傾き検出機能付き電動ドライバは、重力方向に関するドライバビットの軸の角度を検知する３軸加速度センサを内蔵し、傾き検出モードで、ネジ締め面の法線とドライバビットの軸が同一となったときに、該３軸加速度センサで検出した該軸の角度をネジ締め角度として記憶手段に記憶し、通常動作モードで、該記憶手段に記憶した該ネジ締め角度と該３軸加速度センサで検出した該軸の角度との差が所定角度以内であるときだけに、該ドライバビット駆動用のモータの回転を可能にする。
（２）本発明の電動ドライバによるネジ締め付け方法は、内蔵の３軸加速度センサにより重力方向に関するドライバビットの軸の角度を検知し、傾き検出モードで、ネジ締め面の法線とドライバビットの軸が同一となったときに、該３軸加速度センサで検出した該軸の角度をネジ締め角度として記憶し、通常動作モードで、該記憶した該ネジ締め角度と該３軸加速度センサで検出した該軸の角度との差が所定角度以内であるときだけに、該ドライバビット駆動用のモータの回転を可能にする。 In order to solve the above-mentioned problems, the present invention provides the following means.
(1) The electric driver with a tilt detection function of the present invention has a built-in triaxial acceleration sensor that detects the angle of the axis of the driver bit with respect to the direction of gravity, and the normal of the screw tightening surface and the axis of the driver bit in the tilt detection mode. Is stored in the storage means as a screw tightening angle and the screw tightening angle stored in the storage means and the three axes in the normal operation mode. Only when the difference from the angle of the axis detected by the acceleration sensor is within a predetermined angle, the motor for driving the driver bit can be rotated.
(2) The screw tightening method using the electric screwdriver of the present invention detects the angle of the driver bit shaft with respect to the direction of gravity by the built-in triaxial acceleration sensor, and in the tilt detection mode, the screw tightening surface normal and the driver bit shaft Is stored as a screw tightening angle, and in the normal operation mode, the stored screw tightening angle and the three-axis acceleration sensor detect the shaft angle. Only when the difference from the angle of the shaft is within a predetermined angle, the motor for driving the driver bit can be rotated.

本発明によれば、ネジ締め面の法線とドライバビットの軸が同一であることを判定でき、またネジ締め作業者に注意力の維持を求めなくても、ドライバビットの軸とネジ締め面の法線とのなす角度が所定角度以内であるときだけにモータの回転を可能にする傾き検出機能付き電動ドライバ及び電動ドライバによるネジ締め付け方法を提供できる。 According to the present invention, it is possible to determine that the normal of the screw tightening surface is the same as the axis of the driver bit, and the screw bit shaft and the screw tightening surface are not required to maintain the attention of the screw tightening operator. It is possible to provide an electric driver with an inclination detection function that enables rotation of the motor only when an angle formed with the normal line is within a predetermined angle, and a screw tightening method using the electric driver.

本発明の一実施形態である傾き検出機能付き電動ドライバにおける動作モードを示す図である。It is a figure which shows the operation mode in the electric driver with an inclination detection function which is one Embodiment of this invention. 図１に示した本発明の一実施形態の傾き検出機能付き電動ドライバの正面図（Ａ）及び他の実施形態の傾き検出機能付き電動ドライバの正面図（Ｂ）である。It is a front view (A) of the electric driver with an inclination detection function of one embodiment of the present invention shown in FIG. 1 and a front view (B) of an electric driver with an inclination detection function of another embodiment. 図１に示した本発明の一実施形態である傾き検出機能付き電動ドライバの要部を示す図である。It is a figure which shows the principal part of the electric driver with an inclination detection function which is one Embodiment of this invention shown in FIG. 図１に示した本発明の一実施形態である傾き検出機能付き電動ドライバが面接触状態であるときにおける要部を示す正面図（Ａ）およびその電動ドライバがセンサ接触検知状態であるときにおける要部を示す正面図（Ｂ）である。The front view (A) which shows the principal part in case the electric driver with an inclination detection function which is one Embodiment of this invention shown in FIG. 1 is in a surface contact state, and the point in case the electric driver is in a sensor contact detection state It is a front view (B) which shows a part. 図１に示した本発明の一実施形態である傾き検出機能付き電動ドライバにより、ネジ締め面が水平線に対し傾斜しているときにおけるネジ締め角度を検出しているときの検出加速度を例示する図（Ａ）、及びその電動ドライバにより、ネジ締め面が水平であるときにおけるネジ締め角度を検出しているときの検出加速度を例示する図（Ｂ）である。The figure which illustrates the detection acceleration when detecting the screw tightening angle when the screw tightening surface is inclined with respect to the horizontal line by the electric screwdriver with the tilt detecting function which is one embodiment of the present invention shown in FIG. It is a figure (B) which illustrates detection acceleration when detecting the screw tightening angle when the screw tightening surface is horizontal by (A) and its electric driver. 図１に示した本発明の一実施形態の傾き検出機能付き電動ドライバにおいて、モータの回転制御に関連する主要な構成を示すブロック図である。FIG. 2 is a block diagram showing a main configuration related to motor rotation control in the electric driver with an inclination detection function of the embodiment of the present invention shown in FIG. 1. 本発明の傾き検出機能付き電動ドライバにおける可動部の変形例を示す斜視図（Ａ）及び平面図（Ｂ）である。It is the perspective view (A) and top view (B) which show the modification of the movable part in the electric driver with an inclination detection function of this invention. 図１に示した本発明の一実施形態である傾き検出機能付き電動ドライバの要部であって、図３に示す構成にばね７０を付加した構成（変形例）を示す図である。FIG. 4 is a diagram showing a configuration (modification) of the main part of the electric driver with an inclination detection function according to the embodiment of the present invention shown in FIG. 1, in which a spring 70 is added to the configuration shown in FIG. 3.

図１から図６は本発明の一実施形態である傾き検出機能付き電動ドライバを示す図である。以下に、図１から図６を参照してその傾き検出機能付き電動ドライバ及びその電動ドライバによるネジ締め付け方法を説明する。 FIG. 1 to FIG. 6 are views showing an electric driver with a tilt detection function according to an embodiment of the present invention. Hereinafter, an electric driver with an inclination detection function and a screw tightening method using the electric driver will be described with reference to FIGS.

本実施の形態の傾き検出機能付き電動ドライバ１は、電動ドライバ本体１１、電動ドライバ本体１１に備えられる切替スライドスイッチ１３、固定部１４、可動部１５、センサ起動スイッチ（接触感知手段）２１ａ，２１ｂ、３軸加速度センサ２２、制御部２３、モータ２４を含んで構成される。図において、符号１００は切替スライドスイッチ１３のスライド方向を示す矢印であり、符号１０１は可動部１５の進退方向を示す矢印である。また、符号１１ａは傾き検出機能付き電動ドライバ本体１１の先端部を示す。符号１４ａ及び１４ｂは、固定部１４における上部及び下部の内側面をそれぞれ示し、符号１４ｃは、固定部１４の一方の端面であって、傾き検出の際に、ネジ締めの対象物におけるネジ締め面２に接触させる側の面を示す。符号１５ａは可動部１５の上部に設けた鍔部を示し、符号１５ａ１は鍔部１５ａのセンサ起動スイッチ側端面を示し、符号１５ｂは、可動部１５の一方の端面であって、センサ起動スイッチ２１ａ，２１ｂから遠い側のものを示す。 The electric driver 1 with an inclination detection function according to the present embodiment includes an electric driver main body 11, a switching slide switch 13, a fixed portion 14, a movable portion 15, and sensor activation switches (contact sensing means) 21a and 21b provided in the electric driver main body 11. A three-axis acceleration sensor 22, a control unit 23, and a motor 24 are included. In the figure, reference numeral 100 is an arrow indicating the sliding direction of the switching slide switch 13, and reference numeral 101 is an arrow indicating the advancing / retreating direction of the movable portion 15. Reference numeral 11a denotes the tip of the electric driver main body 11 with a tilt detection function. Reference numerals 14a and 14b denote inner and lower inner surfaces of the fixed portion 14, respectively, and reference numeral 14c denotes one end face of the fixed portion 14, which is a screw tightening surface of the object to be screwed when detecting the inclination. 2 shows a surface on the side to be brought into contact with. Reference numeral 15a denotes a flange provided on the upper part of the movable part 15, reference numeral 15a1 denotes a sensor activation switch side end face of the flange 15a, and reference numeral 15b denotes one end face of the movable part 15, which is a sensor activation switch 21a. , 21b is the far side.

また、図３に示すように、ａはドライバビット１２の径、ｂは可動部１５における鍔部１５ａの径、ｃは可動部１５の内周面の径、ｄは固定部１４の外径、ｅは固定部１４の下部にあって、可動部１５の外周の摺動面との摺動面をなす円筒内面１４ｂ（内周）の径、ｆは可動部１５の外周の摺動面の径である。ａ，ｂ，ｃ，ｄ，ｅ及びｆの関係は、ｄ＞ｂ＞ｅ＞ｆ＞ｃ＞ａである。可動部１５の内周面の径ｃはドライバビット１２の径ａより大きいので、図４（Ｂ）に示すようにドライバビット１２の先端が可動部１５の端面１５ｂ付近までに至る状態（図１（Ｄ）の加速度測定時）も可能である。図４（Ａ）に示すように、固定部１４におけるセンサ起動スイッチ２１ａ，２１ｂの接触部から固定部１４の一方の端面１４ｃ（図３参照）までの距離ｇと、可動部１５の中心線方向の長さｈとは等しい。ｈは、可動部１５の端面１５ａ１と１５ｂとの距離である。 Also, as shown in FIG. 3, a is the diameter of the driver bit 12, b is the diameter of the flange portion 15a in the movable portion 15, c is the diameter of the inner peripheral surface of the movable portion 15, d is the outer diameter of the fixed portion 14, e is a diameter of a cylindrical inner surface 14b (inner periphery) which is located below the fixed portion 14 and forms a sliding surface with the outer peripheral sliding surface of the movable portion 15, and f is a diameter of the outer sliding surface of the movable portion 15. It is. The relationship among a, b, c, d, e, and f is d> b> e> f> c> a. Since the diameter c of the inner peripheral surface of the movable portion 15 is larger than the diameter a of the driver bit 12, the state where the tip of the driver bit 12 reaches the vicinity of the end surface 15b of the movable portion 15 as shown in FIG. (D) (acceleration measurement) is also possible. As shown in FIG. 4A, the distance g from the contact portion of the sensor activation switches 21a and 21b in the fixed portion 14 to one end face 14c (see FIG. 3) of the fixed portion 14 and the direction of the center line of the movable portion 15 Is equal to the length h. h is the distance between the end faces 15a1 and 15b of the movable portion 15.

固定部１４は、電動ドライバ本体１１の筐体に設けられ、その筐体に設けられている円筒（図示は省略）の内周を案内面として、ドライバビット１２の軸方向に進退可能である。固定部１４の内周には、径が鍔部１５ａの径ｂより僅か大きく、可動部１５の鍔部１５ａと摺動する上部摺動面と、径がｅであり、可動部１５の下部と摺動する下部摺動面１４ｂが設けてある。その上部摺動面と下部摺動面１４ｂとの境界が段差１４ｄをなしている。上部摺動面はセンサ起動スイッチ２１ａ，２１ｂの取付面１４ｅと段差１４ｄとの間にあり、下部摺動面１４ｂは段差１４ｄと端面１４ｃとの間にある。切替スライドスイッチ１３は固定部１４に連結されている。切替スライドスイッチ１３の手動操作により、ドライバビット１２の軸方向に固定部１４を進退させることができる。本実施の形態では、まず固定部１４をドライバビット１２の軸方向に進出させて傾き検出モード（図１（Ｃ））とする。 The fixing portion 14 is provided in the housing of the electric driver main body 11 and can advance and retreat in the axial direction of the driver bit 12 with the inner periphery of a cylinder (not shown) provided in the housing as a guide surface. On the inner periphery of the fixed portion 14, the diameter is slightly larger than the diameter b of the flange portion 15 a, an upper sliding surface that slides with the flange portion 15 a of the movable portion 15, a diameter e, and a lower portion of the movable portion 15 A lower sliding surface 14b that slides is provided. The boundary between the upper sliding surface and the lower sliding surface 14b forms a step 14d. The upper sliding surface is between the mounting surface 14e and the step 14d of the sensor activation switches 21a and 21b, and the lower sliding surface 14b is between the step 14d and the end surface 14c. The change slide switch 13 is connected to the fixed portion 14. The fixed portion 14 can be moved back and forth in the axial direction of the driver bit 12 by manual operation of the switching slide switch 13. In the present embodiment, first, the fixing portion 14 is advanced in the axial direction of the driver bit 12 to enter the inclination detection mode (FIG. 1C).

可動部１５は、頭部に設けた径ｂの鍔部１５ａと、鍔部１５ａと一体であって径ｆの本体部とでなり、外周の摺動面で固定部１４の内周の摺動面と摺動し、固定部１４の軸方向に進退可能である。鍔部１５ａの径ｂは、固定部１４の上部摺動面の径ｂ'（ｂ'の図示は省略。）より僅かに小さいが、鍔部１５ａの外周が固定部１４の上部摺動面にほぼ接触する程度にその上部摺動面の径ｂ'に近い。ただし、鍔部１５ａの厚みは極く薄いので、ｂとｂ'との差は僅かでも、可動部１５はその軸を固定部１４の軸に対し傾き得る。可動部１５の頭部に設けた鍔部１５ａの径ｂが固定部１４の下部摺動面の内周（径：ｅ）より大きいので、可動部１５が固定部１４から抜け落ちることはない。電動ドライバ本体１１を手で保持し、電動ドライバ本体１１の姿勢を調整し、ドライバビット１２の先端が垂直に下方を向くようにすると、可動部１５は自重により、最下端まで下がる。可動部１５が最下端にあるとき、鍔部１５ａの下面は、固定部１４における径ｅの段差に当接している。この状態が図１（Ｃ）に示す傾き検出モードである。 The movable portion 15 is composed of a flange portion 15a having a diameter b provided on the head and a main body portion having a diameter f which is integral with the flange portion 15a, and slides on the inner periphery of the fixed portion 14 on the outer peripheral sliding surface. It slides on the surface and can advance and retreat in the axial direction of the fixed portion 14. The diameter b of the flange portion 15 a is slightly smaller than the diameter b ′ of the upper sliding surface of the fixed portion 14 (the illustration of b ′ is omitted), but the outer periphery of the flange portion 15 a is the upper sliding surface of the fixed portion 14. It is close to the diameter b ′ of the upper sliding surface to such an extent that it almost contacts. However, since the thickness of the flange portion 15a is extremely thin, the movable portion 15 can tilt its axis with respect to the axis of the fixed portion 14 even if the difference between b and b ′ is slight. Since the diameter b of the flange portion 15 a provided at the head of the movable portion 15 is larger than the inner circumference (diameter: e) of the lower sliding surface of the fixed portion 14, the movable portion 15 does not fall out of the fixed portion 14. When the electric driver main body 11 is held by hand, the posture of the electric driver main body 11 is adjusted, and the tip of the driver bit 12 is directed vertically downward, the movable portion 15 is lowered to the lowest end by its own weight. When the movable portion 15 is at the lowermost end, the lower surface of the flange portion 15a is in contact with the step of the diameter e in the fixed portion 14. This state is the tilt detection mode shown in FIG.

検出モードにおいて、電動ドライバ本体１１をネジ締め対象物のネジ締め面２に近接させ、図４（Ａ）に示すように、可動部１５の先端側（図１の下側）の端面１５ｂ（図３参照）をネジ締め面２に当接させ、更に電動ドライバ本体１１を下げ、図４（Ｂ）に示すように、固定部１４の先端側（図１の下側）の端面１４ｃ（図３参照）をネジ締め面２に当接させる。このように、傾き検出モードから更に電動ドライバ本体１１を下げる過程で、可動部１５は固定部１４内に後退し、図１（Ｄ）の加速度測定の状態に至る。この加速度測定の状態は、前述の面接触状態に対応する。図１（Ｄ）の加速度測定状態は図４（Ｂ）に示す状態と同じである。 In the detection mode, the electric driver main body 11 is brought close to the screw tightening surface 2 of the object to be screwed, and as shown in FIG. 4 (A), the end surface 15b (the lower side in FIG. 1) of the movable portion 15 is shown. 3) is brought into contact with the screw tightening surface 2, and the electric driver main body 11 is further lowered. As shown in FIG. 4B, the end surface 14c (FIG. 3) on the distal end side (lower side in FIG. 1) of the fixing portion 14 is obtained. Reference) is brought into contact with the screw tightening surface 2. Thus, in the process of further lowering the electric driver main body 11 from the tilt detection mode, the movable portion 15 is retracted into the fixed portion 14 and reaches the state of acceleration measurement of FIG. This acceleration measurement state corresponds to the aforementioned surface contact state. The acceleration measurement state in FIG. 1D is the same as the state shown in FIG.

電動ドライバ本体１１の上下方向（ドライバビット１２の軸方向）移動は手動で行う。そこで、電動ドライバ本体１１の姿勢は必ずしも安定せず、加速度測定の状態（図１（Ｄ））では、ネジ締め面２に当接した固定部１４の端面１４ｃは、ネジ締め面２に平行であることもあるし、平行でない場合もあり得る。固定部１４はドライバビット１２と同軸であるから、固定部１４の端面１４ｃがネジ締め面２に平行に当接すれば、ドライバビット１２の軸とネジ締め面２とは直交し、すなわちドライバビット１２の軸はネジ締め面２の法線に一致する。 The electric driver main body 11 is moved manually in the vertical direction (axial direction of the driver bit 12). Therefore, the posture of the electric driver main body 11 is not always stable. In the acceleration measurement state (FIG. 1D), the end surface 14c of the fixing portion 14 that is in contact with the screw tightening surface 2 is parallel to the screw tightening surface 2. It may or may not be parallel. Since the fixing portion 14 is coaxial with the driver bit 12, if the end surface 14c of the fixing portion 14 abuts the screw fastening surface 2 in parallel, the axis of the driver bit 12 and the screw fastening surface 2 are orthogonal, that is, the driver bit 12 This axis coincides with the normal of the screw tightening surface 2.

前述のように、固定部１４におけるセンサ起動スイッチ２１ａ，２１ｂから固定部１４の一方の端面１４ｃ（図３参照）までの距離ｇと、可動部１５の中心線方向の長さ（端面１５ａ１と１５ｂとの距離）ｈとは等しいので、固定部１４の端面１４ｃがネジ締め面２に平行であれば、図１（Ｄ）及び図４（Ｂ）に示す加速度測定時には、可動部１５の上側端面（鍔部１５ａの上側端面１５ａ１）はセンサ起動スイッチ２１ａ及び２１ｂの接触部に等しい力で同時に接触し、センサ起動スイッチ２１ａ及び２１ｂは接触を感知し、接触信号を出力する。この接触信号は、制御部２３（図６）に設けてある判定部に送られる。判定部は、センサ起動スイッチ２１ａ及び２１ｂの両方から接触信号を受けたときに、ドライバビット１２の軸と同軸の固定部１４の端面１４ｃがネジ締め面２に平行に接触している、即ち、ドライバビット１２の軸とネジ締め面２とは直交していると判定し、他方、センサ起動スイッチ２１ａ又は２１ｂの一方からのみ接触信号を受けたときは、固定部１４の端面１４ｃがネジ締め面２に平行に接触していない、即ち、ドライバビット１２の軸とネジ締め面２とは直交していないと判定する。このように、判定部が、ドライバビット１２の軸と同軸の固定部１４の端面１４ｃがネジ締め面２に平行に接触していると判定したとき、ドライバビット１２の軸がネジ締め面２に直交しているので、このときのドライバビット１２の軸の角度でネジ締め面２のネジ穴にネジを締め付けることにより、ネジ頭部の穴やネジ穴に損傷を与えることなく、またドライバビット１２の先端の磨耗も少なくすることができる。したがって、本実施の形態の傾き検出機能付き電動ドライバは、ネジ締め作業者に注意力の維持を求めなくても、ドライバビット１２の軸とネジ締め面２の法線とのなす角度が一定値以内であるときだけにモータの回転を可能にする。 As described above, the distance g from the sensor activation switches 21a and 21b in the fixed portion 14 to one end surface 14c (see FIG. 3) of the fixed portion 14 and the length in the center line direction of the movable portion 15 (end surfaces 15a1 and 15b). If the end surface 14c of the fixed portion 14 is parallel to the screw tightening surface 2, the upper end surface of the movable portion 15 is measured during the acceleration measurement shown in FIGS. 1 (D) and 4 (B). The upper end surface 15a1 of the flange portion 15a simultaneously contacts the contact portions of the sensor activation switches 21a and 21b with the same force, and the sensor activation switches 21a and 21b sense the contact and output a contact signal. This contact signal is sent to the determination part provided in the control part 23 (FIG. 6). When the determination unit receives contact signals from both of the sensor activation switches 21a and 21b, the end surface 14c of the fixing unit 14 coaxial with the axis of the driver bit 12 is in contact with the screw tightening surface 2 in parallel. When it is determined that the axis of the driver bit 12 and the screw tightening surface 2 are orthogonal to each other and a contact signal is received only from one of the sensor activation switches 21a or 21b, the end surface 14c of the fixing portion 14 is screw tightening surface. 2, that is, it is determined that the axis of the driver bit 12 and the screw tightening surface 2 are not orthogonal to each other. As described above, when the determination unit determines that the end surface 14c of the fixing portion 14 coaxial with the axis of the driver bit 12 is in contact with the screw tightening surface 2, the shaft of the driver bit 12 contacts the screw tightening surface 2. Since they are orthogonal to each other, by tightening the screw into the screw hole of the screw fastening surface 2 at the angle of the axis of the driver bit 12 at this time, the screw bit 12 is not damaged and the driver bit 12 is not damaged. The wear of the tip of the can also be reduced. Therefore, in the electric driver with an inclination detection function of the present embodiment, the angle formed by the axis of the driver bit 12 and the normal line of the screw tightening surface 2 is a constant value without requiring the screw tightener to maintain attention. The motor can be rotated only when it is within.

そこで、本実施の形態では、傾き検出モードにおいて、センサ起動スイッチ２１ａ及び２１ｂが同時に接触を検知したときにおける３軸加速度センサ２２（図６）で検知したドライバビット１２の角度をネジ締め角度としてネジ締め角度記憶メモリに記憶する。そして、本実施の形態の電動ドライバによりネジ締め面２のネジ穴にネジを締め付ける通常動作モード（図１（Ｂ））では、３軸加速度センサ２２（図６）で検知したドライバビット１２の角度とその記憶メモリに記憶したネジ締め角度との差である軸傾き角度が所定角度以下であるか否かをモータ回転許容部で判断し、その軸傾き角度が所定角度以下であるときだけに、モータに電源が供給でき、モータが回転できるようにしてある。図１（Ａ）は、通常モードにおいてネジ締め面２に設けてあるネジ穴（図示省略）にネジ３を締め付ける状態を示している。軸傾き角度が所定角度以下であるとモータ回転許容部が判定しないときは、ドライバビット１２を回転させるモータには電源は供給されない。判定部、ネジ締め角度記憶メモリ及びモータ回転許容部は、図６の制御部２３に設けられる。 Therefore, in the present embodiment, in the tilt detection mode, the angle of the driver bit 12 detected by the triaxial acceleration sensor 22 (FIG. 6) when the sensor activation switches 21a and 21b detect contact at the same time is used as the screw tightening angle. Store in the tightening angle storage memory. Then, in the normal operation mode (FIG. 1B) in which the screw is tightened into the screw hole of the screw tightening surface 2 by the electric driver according to the present embodiment, the angle of the driver bit 12 detected by the three-axis acceleration sensor 22 (FIG. 6). And whether or not the shaft tilt angle, which is the difference between the screw tightening angle stored in the storage memory, is equal to or less than a predetermined angle, is determined by the motor rotation permission unit, and only when the shaft tilt angle is equal to or less than the predetermined angle, Power can be supplied to the motor so that the motor can rotate. FIG. 1A shows a state in which the screw 3 is tightened in a screw hole (not shown) provided in the screw tightening surface 2 in the normal mode. When the motor rotation permission unit does not determine that the shaft inclination angle is equal to or less than the predetermined angle, power is not supplied to the motor that rotates the driver bit 12. The determination unit, screw tightening angle storage memory, and motor rotation allowance unit are provided in the control unit 23 of FIG.

本実施例の電動ドライバ１では、固定部１４の下部摺動面１４ｂの径ｅが可動部１５の本体部の摺動面の径ｆより相当に大きく、固定部１４の下部摺動面１４ｂと可動部１５の本体部の摺動面とは、密着していない。そこで、３軸加速度センサ２２による加速度測定時に、固定部１４の端面１４ｃがネジ締め面２に平行に当接していないと、可動部１５の中心線が、固定部１４の中心線（ドライバビット１２と同軸）と平行ではなくなり、可動部１５の中心線は固定部１４の中心線に対し傾く。この状態では、固定部１４の端面１４ｃの一部および可動部１５の端面１５ｂがネジ締め面２に接触し、可動部１５の上側端面１５ａ１がセンサ起動スイッチ２１ａに接触しても、可動部１５の上側端面１５ａ１は他方のセンサ起動スイッチ２１ｂには接触しない。 In the electric driver 1 of the present embodiment, the diameter e of the lower sliding surface 14b of the fixed portion 14 is considerably larger than the diameter f of the sliding surface of the main body portion of the movable portion 15, and the lower sliding surface 14b of the fixed portion 14 It is not in close contact with the sliding surface of the main body portion of the movable portion 15. Therefore, if the end surface 14c of the fixed portion 14 is not in contact with the screw tightening surface 2 at the time of acceleration measurement by the triaxial acceleration sensor 22, the center line of the movable portion 15 becomes the center line of the fixed portion 14 (driver bit 12). And the center line of the movable portion 15 is inclined with respect to the center line of the fixed portion 14. In this state, even if a part of the end surface 14c of the fixed portion 14 and the end surface 15b of the movable portion 15 are in contact with the screw fastening surface 2 and the upper end surface 15a1 of the movable portion 15 is in contact with the sensor activation switch 21a, the movable portion 15 The upper end face 15a1 does not contact the other sensor activation switch 21b.

傾き検出モード（図１（Ｃ））において、上述のように、センサ起動スイッチ２１ａ及び２１ｂの一方のみが接触を感知したときは、３軸加速度センサ２２で測定したドライバビット１２の軸角度をネジ締め角度記憶メモリに記憶しない。 In the tilt detection mode (FIG. 1C), as described above, when only one of the sensor activation switches 21a and 21b senses contact, the shaft angle of the driver bit 12 measured by the three-axis acceleration sensor 22 is screwed. It is not stored in the tightening angle memory.

上記実施の形態では、説明を容易にするために、センサ起動スイッチ２１は２つ（２１ａ及び２１ｂ）であるとした。しかし、センサ起動スイッチ２１の個数が３又はそれ以上であれば、傾き検出モードにおいて、ドライバビット１２の軸がネジ締め面２の法線に対してなす角度が閾値以内であるか否かを判定部で正確に判定できるので、センサ起動スイッチ２１の個数が３又はそれ以上あることが好ましい。 In the above embodiment, in order to facilitate the explanation, the sensor activation switch 21 is assumed to be two (21a and 21b). However, if the number of sensor activation switches 21 is 3 or more, it is determined whether or not the angle formed by the axis of the driver bit 12 with respect to the normal of the screw tightening surface 2 is within a threshold value in the inclination detection mode. It is preferable that the number of sensor activation switches 21 is 3 or more since the determination can be made accurately by the unit.

上記実施の形態では、ネジ締め面２が水平面にある場合を想定して説明した。しかし、本実施の形態は、ネジ締め面２が水平面から傾斜していても実施可能である。例えば、図５（Ａ）に示すように、ネジ締め面２が水平面から４５度傾いていても、可動部１５は、傾き検出モードにおいて、自重により固定部１４からネジ締め面２側に向かって滑り降りるので、可動部１５の端面１５ｂをネジ締め面２に当接することができる。 In the said embodiment, the case where the screw fastening surface 2 exists in a horizontal surface was demonstrated. However, this embodiment can be implemented even if the screw fastening surface 2 is inclined from the horizontal plane. For example, as shown in FIG. 5 (A), even if the screw tightening surface 2 is inclined 45 degrees from the horizontal plane, the movable portion 15 moves from the fixed portion 14 toward the screw tightening surface 2 by its own weight in the inclination detection mode. Since it slides down, the end surface 15b of the movable part 15 can be brought into contact with the screw tightening surface 2.

上記実施の形態では、傾き検出モードにおいて、可動部１５が自重により固定部１４からネジ締め面２側に向かって滑り降りるとしたが、ネジ締め面２が垂直近くまで水平面から傾いていたり、ネジ締め面２が水平であっても天井のように、ドライバビット１２の軸を上向きにせざるを得ないときは、以上に説明した実施の形態は適用できないの。このような用途には、図８に示すように、ばね７０を設け、可動部１５にセンサ起動スイッチ２１から固定部１４の端面１４ｃの方向に向かう付勢を与える。図８は、図１から図６に示した実施の形態の変形例である。図８の変形例では、鍔部１５ａの径を図３のものよりやや大きくし、また固定部１４におけるセンサ起動スイッチ２１の外側に溝を設け、その鍔部１５ａの外縁近傍と溝との間にばね７０を設けてある。図８の変形例の採用により、ネジ締め面２が垂直近くまで水平面から傾いていたり、ネジ締め面２が水平であっても、天井のように、ドライバビット１２の軸を上向きにせざるを得ないときでも、ネジ締めが可能である。このときのドライバビット１２の軸の角度でネジ締め面２のネジ穴にネジを締め付けることにより、ネジ頭部の穴やネジ穴に損傷を与えることなく、またドライバビット１２の先端の磨耗も少なくすることができる。 In the above-described embodiment, in the tilt detection mode, the movable portion 15 slides down from the fixed portion 14 toward the screw tightening surface 2 due to its own weight. However, the screw tightening surface 2 is inclined from the horizontal plane to near vertical, Even when the surface 2 is horizontal, the embodiment described above cannot be applied when the axis of the driver bit 12 has to be upward like the ceiling. For such an application, as shown in FIG. 8, a spring 70 is provided to bias the movable portion 15 from the sensor activation switch 21 toward the end surface 14 c of the fixed portion 14. FIG. 8 shows a modification of the embodiment shown in FIGS. In the modified example of FIG. 8, the diameter of the flange portion 15a is slightly larger than that of FIG. 3, and a groove is provided on the outer side of the sensor activation switch 21 in the fixed portion 14, and the gap between the vicinity of the outer edge of the flange portion 15a and the groove is provided. A spring 70 is provided. By adopting the modified example of FIG. 8, even if the screw tightening surface 2 is inclined from the horizontal plane to near vertical or the screw tightening surface 2 is horizontal, the axis of the driver bit 12 must be directed upward like a ceiling. Even when it is not, screw tightening is possible. By tightening the screw into the screw hole of the screw tightening surface 2 at the angle of the axis of the driver bit 12 at this time, the screw head hole and the screw hole are not damaged, and the tip of the driver bit 12 is less worn. can do.

図７は、変形例の可動部５０を示す図である。図７において、５０ａ，５０ｂ，５０ｃ，５０ｄは可動部５０の摺動円柱、５０ｅは可動部５０におけるドライバビット挿入円筒を示す。図７（Ａ）は斜視図、同図（Ｂ）は平面図である。図３に構造を詳しく示した図１乃至図６の実施の形態では、可動部１５は一本の円筒でなっていたが、図７の可動部７０は、４本の摺動円柱を備える。図７の変形例は、４本の円柱であるが、３本以上の多角形であってもよい。 FIG. 7 is a diagram illustrating a movable unit 50 according to a modification. In FIG. 7, 50 a, 50 b, 50 c, and 50 d are sliding cylinders of the movable portion 50, and 50 e is a driver bit insertion cylinder in the movable portion 50. FIG. 7A is a perspective view, and FIG. 7B is a plan view. In the embodiment shown in FIG. 1 to FIG. 6 whose structure is shown in detail in FIG. 3, the movable portion 15 is a single cylinder, but the movable portion 70 in FIG. 7 includes four sliding cylinders. Although the modification of FIG. 7 is four cylinders, it may be three or more polygons.

以上に、実施形態を挙げ、本発明を詳しく説明したが、本発明はこれらの実施の形態に限定されるものでないことは勿論である。 While the present invention has been described in detail with reference to the embodiments, it is needless to say that the present invention is not limited to these embodiments.

１傾き検出機能付き電動ドライバ
２ネジ締め面
３ネジ
１１傾き検出機能付き電動ドライバ本体
１１ａ傾き検出機能付き電動ドライバ本体の先端部
１２ドライバビット
１３切替スライドスイッチ
１４固定部
１４ａ鍔部１５ａの摺動面と摺動する固定部１４の内側面
１４ｂ可動部１５下部摺動面と摺動する固定部１４の内側面
１４ｃネジ締め面２に接触する側の固定部の端面
１４ｄ固定部１４における段差
１４ｅ固定部１４におけるセンサ起動スイッチ２１ａ，２１ｂの取付面
１５可動部
１５ａ可動部１５の鍔部
１５ａ１鍔部１５ａのセンサ起動スイッチ側端面
１５ｂネジ締め面２に接触する側の可動部の端面
２１，２１ａ，２１ｂセンサ起動スイッチ（接触感知手段）
２２３軸加速度センサ
２３制御部
２４モータ
５０可動部（変形例）
５０ａ，５０ｂ，５０ｃ，５０ｄ可動部５０の摺動円柱
５０ｅ可動部５０におけるドライバビット挿入円筒
７０ばね
１００切替スライドスイッチのスライド方向を示す矢印
１０１可動部の進退方向を示す矢印
ａドライバビット１２の径
ｂ可動部１５における鍔部１５ａの外径
ｃ可動部１５の内周面の径
ｄ固定部１４の外径
ｅ固定部１４の下部にあって、可動部１５の外周の摺動面との摺動面をなす円筒内面（内周）の径
ｆ可動部１５の外周の摺動面の径（外径）
ｇセンサ起動スイッチ２１の接触部から一方の端面１４ｃまでの距離
ｈ可動部１５の中心線方向の長さ DESCRIPTION OF SYMBOLS 1 Electric driver with an inclination detection function 2 Screw tightening surface 3 Screw 11 Electric driver main body with an inclination detection function 11a The front-end | tip part of the electric driver main body with an inclination detection function 12 Driver bit 13 Switching slide switch 14 Fixing part 14a Sliding surface of the collar part 15a The inner surface 14b of the fixed portion 14 that slides with the movable portion 15 The lower sliding surface of the movable portion 15 and the inner surface 14c of the fixed portion 14 that slides The end surface 14d of the fixed portion that contacts the screw tightening surface 2 14d The step 14e at the fixed portion 14 Mounting surfaces of the sensor activation switches 21a and 21b in the portion 14 15 movable portion 15a flange 15a1 of the movable portion 15 sensor activation switch side end surface 15b of the flange 15a end surfaces 21a, 21a of the movable portion on the side in contact with the screw tightening surface 2 21b Sensor start switch (contact sensing means)
22 3-axis acceleration sensor 23 Control part 24 Motor 50 Movable part (modification)
50a, 50b, 50c, 50d Sliding cylinder of the movable part 50e Driver screw insertion cylinder in the movable part 50 70 Spring 100 Arrow indicating the sliding direction of the switching slide switch 101 Arrow indicating the forward / backward direction of the movable part a Diameter of the driver bit 12 b The outer diameter of the flange portion 15a in the movable portion 15 c The diameter of the inner peripheral surface of the movable portion 15 d The outer diameter of the fixed portion 14 e The sliding portion of the lower portion of the fixed portion 14 with the outer sliding surface of the movable portion 15 Diameter of cylindrical inner surface (inner circumference) forming moving surface f Diameter of outer sliding surface of movable part 15 (outer diameter)
g Distance from the contact portion of the sensor activation switch 21 to one end face 14c h Length of the movable portion 15 in the center line direction

Claims

重力方向に関するドライバビットの軸の角度を検知する３軸加速度センサを内蔵し、傾き検出モードで、ネジ締め面の法線とドライバビットの軸が同一となったときに、該３軸加速度センサで検出した該軸の角度をネジ締め角度として記憶手段に記憶し、通常動作モードで、該記憶手段に記憶した該ネジ締め角度と該３軸加速度センサで検出した該軸の角度との差が所定角度以内であるときだけに、該ドライバビット駆動用のモータの回転を可能にすることを特徴とする傾き検出機能付き電動ドライバ。 Built-in triaxial acceleration sensor that detects the angle of the driver bit axis with respect to the direction of gravity. When the normal of the screw tightening surface and the axis of the driver bit are the same in the tilt detection mode, the triaxial acceleration sensor The detected angle of the shaft is stored in the storage means as a screw tightening angle, and a difference between the screw tightening angle stored in the storage means and the angle of the shaft detected by the three-axis acceleration sensor in a normal operation mode is predetermined. An electric driver with an inclination detection function, which enables rotation of the motor for driving the driver bit only when the angle is within an angle.

前記傾き検出モードにおいて前記ドライバビットの軸がネジ締め面の法線と同一であることを検出する傾き検出手段と、前記通常動作モードにおいて前記差が所定角度以内であるときだけに前記モータの回転を可能にするモータ回転許容手段を有し、
前記傾き検出手段は、前記軸と同軸の第１の円筒形摺動面を内周に有する固定部と、第１の円筒形摺動面と摺動する第２の円筒形摺動面を外周に有する可動部と、手動操作に応じ該固定部の一方の端面を前記ドライバビットの先端より更に先まで延伸させる固定部延伸手段と、該固定部に取り付けられた複数の接触感知手段と、該ドライバビットの軸がネジ締め面の法線と同一であるか否かを判定する傾き判定手段とを有してなり、
前記記憶手段は、前記ドライバビットの軸がネジ締め面の法線と同一であると該判定手段が判定したときにおける該３軸加速度センサで検出した該軸の角度を前記ネジ締め角度として記憶し、
前記固定部の一方の端面であり、前記傾き検出モードにおいて前記ネジ締め面に当接される側のネジ締め面当接端面は、前記軸に直交する平面であり、
前記可動部における第２の円筒形摺動面をなす円筒の中心線方向の両端面は該中心線に直交する平面であり、
前記接触感知手段の接触部と前記ネジ締め面当接端面との距離は、前記可動部の前記中心線方向の長さに等しく、
第２の摺動面を第１の摺動面に摺動させながら前記可動部を前記接触感知手段から離隔させる向きの前記軸方向に移動させ、該可動部の前記端面の一方を前記ネジ締め面に接触させた状態を面接触状態と称し、該面接触状態を経て、第２の摺動面を第１の摺動面に摺動させながら該可動部を該接触感知手段に近接させる向きの前記軸方向に移動させ、少なくとも１つの該接触感知手段が接触を検知し、しかも前記ネジ締め面当接端面を該ネジ締め面に平行に接触させた状態をセンサ接触検知状態と称するとき、
前記傾き判定手段は、前記センサ接触検知状態において、全ての前記複数の接触感知手段が前記接触を検知したときだけに、前記ドライバビットの軸がネジ締め面の法線と同一であると判定する
ことを特徴とする傾き検出機能付き電動ドライバ。 Inclination detection means for detecting that the axis of the driver bit is the same as the normal of the screw tightening surface in the inclination detection mode, and rotation of the motor only when the difference is within a predetermined angle in the normal operation mode Motor rotation permitting means that enables
The inclination detecting means includes a fixed portion having a first cylindrical sliding surface coaxial with the shaft on the inner periphery, and a second cylindrical sliding surface sliding with the first cylindrical sliding surface on the outer periphery. A movable part, a fixed part extending means for extending one end face of the fixed part further beyond the tip of the driver bit according to a manual operation, a plurality of contact sensing means attached to the fixed part, Inclination determination means for determining whether or not the axis of the driver bit is the same as the normal of the screw tightening surface;
The storage means stores, as the screw tightening angle, the angle of the shaft detected by the triaxial acceleration sensor when the determining means determines that the axis of the driver bit is the same as the normal line of the screw tightening surface. ,
One end face of the fixed portion, and the screw tightening surface abutting end face on the side abutting on the screw tightening surface in the tilt detection mode is a plane orthogonal to the axis,
Both end surfaces in the center line direction of the cylinder forming the second cylindrical sliding surface in the movable part are planes orthogonal to the center line,
The distance between the contact portion of the contact sensing means and the screw tightening surface contact end surface is equal to the length of the movable portion in the center line direction,
While moving the second sliding surface to the first sliding surface, the movable portion is moved in the axial direction to be separated from the contact sensing means, and one of the end surfaces of the movable portion is screwed. The state in contact with the surface is referred to as the surface contact state, and the direction in which the movable part is brought close to the contact sensing means while the second sliding surface slides on the first sliding surface through the surface contact state. The state in which at least one of the contact sensing means detects contact and the screw tightening surface contact end surface is in parallel with the screw tightening surface is referred to as a sensor contact detection state.
The inclination determination means determines that the axis of the driver bit is the same as the normal of the screw tightening surface only when all of the plurality of contact detection means detect the contact in the sensor contact detection state. An electric driver with an inclination detection function characterized by that.

前記可動部を前記接触感知手段から遠ざける向きの前記軸方向に、該可動部を付勢するばねを有することを特徴とする請求項１又は２の何れかに記載の傾き検出機能付き電動ドライバ。 The electric driver with an inclination detection function according to claim 1, further comprising a spring that biases the movable part in the axial direction in a direction in which the movable part is moved away from the contact sensing unit.

内蔵の３軸加速度センサにより重力方向に関するドライバビットの軸の角度を検知し、傾き検出モードで、ネジ締め面の法線とドライバビットの軸が同一となったときに、該３軸加速度センサで検出した該軸の角度をネジ締め角度として記憶し、通常動作モードで、該記憶した該ネジ締め角度と該３軸加速度センサで検出した該軸の角度との差が所定角度以内であるときだけに、該ドライバビット駆動用のモータの回転を可能にすることを特徴とする電動ドライバによるネジ締め付け方法。 The built-in triaxial acceleration sensor detects the angle of the driver bit axis with respect to the direction of gravity. When the normal of the screw tightening surface and the driver bit axis are the same in the tilt detection mode, the triaxial acceleration sensor The detected angle of the shaft is stored as a screw tightening angle, and only in the normal operation mode when the difference between the stored screw tightening angle and the shaft angle detected by the three-axis acceleration sensor is within a predetermined angle. And a screw tightening method using an electric screwdriver, which enables rotation of the motor for driving the driver bit.

前記傾き検出モードにおいて前記ドライバビットの軸がネジ締め面の法線と同一であることを検出する傾き検出手段と、前記通常動作モードにおいて前記差が所定角度以内であるときだけに、前記モータの回転を可能にするモータ回転許容手段を有し、
前記傾き検出モードにおいて、前記軸と同軸の第１の円筒形摺動面を内周に有する固定部と、第１の円筒形摺動面と摺動する第２の円筒形摺動面を外周に有する可動部と、手動操作に応じ該固定部の一方の端面を前記ドライバビットの先端より更に先まで延伸させる固定部延伸手段と、該固定部に取り付けられた複数の接触感知手段と、該軸の傾き角度が前記閾値以内であるか否かを判定する傾き判定手段とを有してなる傾き検出手段により、前記ドライバビットの軸がネジ締め面の法線と同一であることを検出し、
前記固定部の一方の端面であり、前記傾き検出モードにおいて前記ネジ締め面に当接される側のネジ締め面当接端面は、前記軸に直交する平面としておき、
前記可動部における第２の円筒形摺動面をなす円筒の中心線方向の両端面は該中心線に直交する平面としておき、
前記接触感知手段の接触部と前記ネジ締め面当接端面との距離は、前記可動部の前記中心線方向の長さに等しくしておき、
第２の摺動面を第１の摺動面に摺動させながら前記可動部を前記接触感知手段から離隔させる向きの前記軸方向に移動させ、該可動部の前記端面の一方を前記ネジ締め面に接触させた状態を面接触状態と称し、該面接触状態を経て、第２の摺動面を第１の摺動面に摺動させながら該可動部を該接触感知手段に近接させる向きの前記軸方向に移動させ、少なくとも１つの該接触感知手段が接触を検知し、しかも前記ネジ締め面当接端面を該ネジ締め面に平行に接触させた状態をセンサ接触検知状態と称するとき、
前記傾き判定手段により、前記センサ接触検知状態において、全ての前記複数の接触感知手段が前記接触を検知したときだけに、前記ドライバビットの軸がネジ締め面の法線と同一であると判定する
ことを特徴とする請求項４に記載の電動ドライバによるネジ締め付け方法。 Inclination detection means for detecting that the axis of the driver bit is the same as the normal of the screw tightening surface in the inclination detection mode, and only when the difference is within a predetermined angle in the normal operation mode. Having a motor rotation permitting means that enables rotation;
In the tilt detection mode, a fixed portion having a first cylindrical sliding surface coaxial with the shaft on the inner periphery, and a second cylindrical sliding surface sliding with the first cylindrical sliding surface on the outer periphery A movable part, a fixed part extending means for extending one end face of the fixed part further beyond the tip of the driver bit according to a manual operation, a plurality of contact sensing means attached to the fixed part, An inclination detection means comprising an inclination determination means for determining whether or not the inclination angle of the shaft is within the threshold value detects that the axis of the driver bit is the same as the normal of the screw tightening surface. ,
One end face of the fixed portion, a screw tightening surface abutting end surface on the side abutting on the screw tightening surface in the tilt detection mode is a plane orthogonal to the axis,
Both end faces in the direction of the center line of the cylinder forming the second cylindrical sliding surface in the movable part are set as planes orthogonal to the center line,
The distance between the contact portion of the contact sensing means and the screw tightening surface contact end surface is equal to the length of the movable portion in the center line direction.
While moving the second sliding surface to the first sliding surface, the movable portion is moved in the axial direction to be separated from the contact sensing means, and one of the end surfaces of the movable portion is screwed. The state in contact with the surface is referred to as the surface contact state, and the direction in which the movable part is brought close to the contact sensing means while the second sliding surface slides on the first sliding surface through the surface contact state. The state in which at least one of the contact sensing means detects contact and the screw tightening surface contact end surface is in parallel with the screw tightening surface is referred to as a sensor contact detection state.
The inclination determination means determines that the axis of the driver bit is the same as the normal of the screw tightening surface only when all the plurality of contact detection means detect the contact in the sensor contact detection state. The screw tightening method with an electric screwdriver according to claim 4.

前記可動部を前記接触感知手段から遠ざける向きの前記軸方向に、該可動部をばねにより付勢することを特徴とする請求項４又は５の何れかに記載の電動ドライバによるネジ締め付け方法。 6. The screw tightening method using an electric screwdriver according to claim 4, wherein the movable part is biased by a spring in the axial direction in which the movable part is moved away from the contact sensing means.