JP6735118B2

JP6735118B2 - Hammer drill

Info

Publication number: JP6735118B2
Application number: JP2016041384A
Authority: JP
Inventors: 正規古澤; 啓多森
Original assignee: Makita Corp
Current assignee: Makita Corp
Priority date: 2016-03-03
Filing date: 2016-03-03
Publication date: 2020-08-05
Anticipated expiration: 2036-03-03
Also published as: JP2017154229A

Description

本発明は、先端工具が保持されるツールホルダを、ハウジングに前後移動可能且つ前方へ突出付勢して設け、ツールホルダの前後位置によって動作モードを選択可能としたハンマドリルに関する。 TECHNICAL FIELD The present invention relates to a hammer drill in which a tool holder for holding a tip tool is provided in a housing so as to be movable back and forth and biased forward so that an operation mode can be selected depending on a front and rear position of the tool holder.

ハンマドリルには、特許文献１に開示されるように、ドリルビット等の先端工具を保持するツールホルダをハウジングに前後移動可能且つ前方へ突出付勢して設けると共に、ハウジング内に、モータの回転が伝達される中間軸をツールホルダと平行に設け、その中間軸に、ツールホルダに回転を伝達するギヤと、中間軸の回転をツールホルダ内に収容したピストンシリンダ等の打撃部材の往復動に変換する変換部材と、ツールホルダの前後移動と連係して変換部材と係脱するクラッチとを設けたものが知られている。このハンマドリルでは、モード切替部材の操作により、ツールホルダの後退をクラッチが変換部材と係合しない位置で規制することでドリルモードが選択でき、ツールホルダの後退をクラッチが変換部材と係合する位置まで許容することでハンマドリルモードが選択できるようになっている。 In the hammer drill, as disclosed in Patent Document 1, a tool holder for holding a tip tool such as a drill bit is provided in the housing so as to be movable back and forth and biased forward, and rotation of a motor is performed in the housing. The intermediate shaft to be transmitted is provided in parallel with the tool holder, and the intermediate shaft has a gear that transmits rotation to the tool holder and the rotation of the intermediate shaft is converted into reciprocating motion of a striking member such as a piston cylinder housed in the tool holder. It is known to provide a conversion member that operates and a clutch that engages and disengages with the conversion member in cooperation with the back and forth movement of the tool holder. In this hammer drill, by operating the mode switching member, the drill mode can be selected by restricting the backward movement of the tool holder at the position where the clutch does not engage the conversion member, and the backward movement of the tool holder can be selected at the position where the clutch engages the conversion member. By allowing up to, the hammer drill mode can be selected.

特許第４７４６９２０号公報Japanese Patent No. 4746920

このような小型のハンマドリルでは、中間軸に設けたギヤとツールホルダに設けたギヤとが常に噛合状態であることから、動作モードとしてドリルモードとハンマドリルモードとが選択できるにとどまり、ハンマモードも選択できる大型のハンマドリルのような使い勝手が求められていた。 In such a small hammer drill, since the gear provided on the intermediate shaft and the gear provided on the tool holder are always in mesh with each other, only the drill mode and the hammer drill mode can be selected as the operation mode, and the hammer mode is also selected. There was a need for usability like a large hammer drill that can be used.

そこで、本発明は、前方へ突出付勢されるツールホルダの前後位置によって動作モードを選択可能とするものであっても、さらなる使い勝手の向上が期待できるハンマドリルを提供することを目的としたものである。 Therefore, the present invention has an object to provide a hammer drill that can be expected to be further improved in usability even if the operation mode can be selected depending on the front and rear positions of the tool holder that is urged forward. is there.

上記目的を達成するために、請求項１に記載の発明は、モータを収容するハウジングと、先端工具が保持可能で、ハウジングに前後移動可能且つ前方へ突出付勢して設けられるツールホルダと、ツールホルダ内へ前後移動可能に設けられる打撃部材と、ハウジング内でツールホルダと平行に設けられ、モータの回転が伝達される中間軸と、中間軸に設けられ、中間軸の回転をツールホルダに伝達するギヤと、中間軸に設けられ、中間軸の回転を打撃部材の往復動に変換する変換部材と、を含んでなるハンマドリルであって、
中間軸へ一体回転可能且つ軸方向へスライド可能に設けられ、ツールホルダの前後移動と連係して、変換部材と噛合する後退位置と、変換部材との噛合が解除される前進位置との間を前後移動するクラッチをさらに含み、
ギヤが、中間軸と係合して中間軸と一体回転する後側の係合位置と、中間軸との係合が解除されて中間軸の回転が伝達されない前側の非係合位置との間で前後へスライド可能に設けられると共に、
ツールホルダに、ツールホルダと一体に前後移動する規制部材が設けられ、
ハウジング内に、中間軸と平行に支持されるガイド軸と、ギヤに係止してガイド軸に沿って前後移動可能なスライド部材と、スライド部材をギヤの係合位置へ付勢する付勢手段と、が設けられ、
２つの偏心ピンを備え、回転操作により、規制部材の前後位置と、スライド部材の前後位置とをハウジングの外部から切替可能なモード切替部材が設けられて、
モード切替部材の回転操作により、
一方の偏心ピンが規制部材の後退を規制してツールホルダ及びクラッチを前進位置に維持する位置にあり、他方の偏心ピンがスライド部材の後退を許容してギヤを係合位置にスライドさせる位置にあって、ギヤが中間軸と一体回転してツールホルダに回転のみ生じさせるドリルモードと、
一方の偏心ピンが規制部材とツールホルダ及びクラッチとの後退を許容する位置にあり、他方の偏心ピンがスライド部材の後退を許容してギヤを係合位置にスライドさせる位置にあって、ギヤが中間軸と一体回転してツールホルダに回転と打撃部材の往復動とを生じさせるハンマドリルモードと、
一方の偏心ピンが規制部材とツールホルダ及びクラッチとの後退を許容する位置にあり、他方の偏心ピンがスライド部材を前進させてギヤを非係合位置へスライドさせる位置にあって、ギヤが中間軸の回転と切り離されて打撃部材の往復動のみを生じさせるハンマモードと、の３つの動作モードが選択可能であることを特徴とする。
請求項２に記載の発明は、請求項１の構成において、ギヤの非係合位置でギヤの回転を規制する回転規制手段が設けられていることを特徴とする。
請求項３に記載の発明は、請求項１又は２の構成において、中間軸の端部に、変換部材の設置側よりも小径となる小径部が形成されて、ギヤは、小径部に外装されて、係合位置では小径部の根元に設けた係合部と係合して中間軸と一体回転することを特徴とする。
請求項４に記載の発明は、請求項１乃至３の何れかの構成において、モータは、ハウジング内における中間軸の下側で、回転軸の軸線が中間軸と交差する向きで配置されて、ツールホルダの後方にはハンドルが設けられることを特徴とする。 In order to achieve the above object, the invention according to claim 1 is a housing that accommodates a motor, a tool holder that can hold a tip tool, is movable forward and backward in the housing, and is provided with a forward biasing force. A striking member that can be moved back and forth into the tool holder, an intermediate shaft that is provided in parallel with the tool holder in the housing, and that transmits the rotation of the motor, and an intermediate shaft that are provided to the tool holder. A hammer drill comprising: a transmission gear; and a conversion member, which is provided on the intermediate shaft and converts the rotation of the intermediate shaft into reciprocating motion of a striking member,
It is provided so as to be integrally rotatable with the intermediate shaft and slidable in the axial direction, and is linked with the back-and-forth movement of the tool holder between a retracted position where it meshes with the conversion member and a forward position where the meshing with the conversion member is released. Further includes a clutch that moves back and forth,
Between the rear engagement position where the gear engages with the intermediate shaft and rotates integrally with the intermediate shaft, and the front non-engagement position where the engagement with the intermediate shaft is released and rotation of the intermediate shaft is not transmitted. It is slidable forward and backward with
The tool holder is provided with a regulating member that moves back and forth integrally with the tool holder,
A guide shaft that is supported in parallel with the intermediate shaft in the housing, a slide member that is locked to the gear and is movable back and forth along the guide shaft, and a biasing unit that biases the slide member to the gear engagement position. And are provided,
A mode switching member that includes two eccentric pins and that can switch the front-rear position of the regulating member and the front-rear position of the slide member from the outside of the housing by a rotating operation is provided.
By rotating the mode switching member ,
One of the eccentric pins is in a position that regulates the retracting of the regulating member to maintain the tool holder and the clutch in the forward position, and the other eccentric pin is in the position that allows the sliding member to retract and slide the gear to the engaging position. There is a drill mode in which the gear rotates together with the intermediate shaft and causes only rotation in the tool holder,
One of the eccentric pins is in a position that allows the restricting member, the tool holder, and the clutch to retract, and the other eccentric pin is in a position that allows the sliding member to retract and slides the gear to the engaging position. A hammer drill mode that rotates integrally with the intermediate shaft to cause rotation of the tool holder and reciprocating motion of the striking member,
One of the eccentric pins is in a position that allows the restricting member, the tool holder, and the clutch to retract, and the other eccentric pin is in a position that advances the slide member to slide the gear to the disengagement position, and the gear is in the middle position. It is characterized in that three operation modes, that is, a hammer mode that is separated from the rotation of the shaft and that causes only the reciprocating motion of the striking member, are selectable.
According to a second aspect of the present invention, in the configuration of the first aspect , a rotation restricting unit that restricts rotation of the gear at the gear disengagement position is provided.
According to a third aspect of the present invention, in the configuration of the first or second aspect , a small diameter portion having a diameter smaller than that of the conversion member installation side is formed at the end portion of the intermediate shaft, and the gear is mounted on the small diameter portion. At the engagement position, it engages with an engagement portion provided at the base of the small diameter portion and rotates integrally with the intermediate shaft.
According to a fourth aspect of the present invention, in the configuration according to any one of the first to third aspects, the motor is arranged below the intermediate shaft in the housing in a direction in which the axis of the rotating shaft intersects the intermediate shaft. A handle is provided behind the tool holder.

請求項１に記載の発明によれば、前方へ突出付勢されるツールホルダの前後位置によって動作モードを選択可能とする小型のハンマドリルであっても、ハンマモードを選択でき、さらなる使い勝手の向上が期待できる。
また、ギヤのスライドによって中間軸からの回転伝達の切替が容易に行える。
さらに、ドリルモードがさらに選択可能であるので、３つの動作モードが使用でき、作業の幅が広がる。
加えて、スライド部材を介してギヤをスライドさせるので、ギヤのスライド位置の切替がスムーズに行える。
そして、モード切替部材に設けた偏心ピンでスライド部材を移動させるので、１つのモード切替部材の操作によってハンマモードの選択も行える。
請求項２に記載の発明によれば、請求項１の効果に加えて、回転規制手段の採用により、ハンマモードでの先端工具の回転をロックでき、ハツリ作業等がしやすくなる。
請求項３に記載の発明によれば、請求項１又は２の効果に加えて、中間軸に設けた小径部にギヤを設けたことで、ギヤを小型化でき、省スペース化に繋がる。
請求項４に記載の発明によれば、請求項１乃至３の何れかの効果に加えて、モータとハンドルの配置によって前後方向の寸法をコンパクト化できると共に、ツールホルダの真後ろに設けたハンドルによって押し荷重もロスなく加えることができる。
According to the invention described in claim 1, even with a small hammer drill capable of selecting the operation mode depending on the front and rear position of the tool holder that is urged forward, the hammer mode can be selected, and the usability is further improved. Can be expected.
Further, the transmission of rotation from the intermediate shaft can be easily switched by sliding the gear.
Further , since the drill mode can be further selected, three operation modes can be used, and the range of work is expanded.
In addition, since the gear is slid through the slide member, the sliding position of the gear can be smoothly switched.
Since the slide member is moved by the eccentric pin provided on the mode switching member, the hammer mode can be selected by operating one mode switching member.
According to the invention described in claim 2 , in addition to the effect of claim 1 , by employing the rotation restricting means, the rotation of the tip tool in the hammer mode can be locked, and the chipping work or the like becomes easy.
According to the invention described in claim 3 , in addition to the effect of claim 1 or 2 , by providing the gear on the small diameter portion provided on the intermediate shaft, the gear can be downsized, leading to space saving.
According to the invention of claim 4 , in addition to the effect of any one of claims 1 to 3 , the dimension in the front-rear direction can be made compact by the arrangement of the motor and the handle, and the handle provided directly behind the tool holder can be used. Pushing load can be applied without loss.

ハンマドリルの全体図である（ドリルモード）。It is a general view of a hammer drill (drill mode). ハンマドリルの全体図である（ハンマドリルモード）。It is a general view of a hammer drill (hammer drill mode). クラッチとボススリーブとの噛み合い部分の説明図で、（Ａ）が噛み合い前を、（Ｂ）が噛み合い状態をそれぞれ示す。6A and 6B are explanatory views of a meshing portion between the clutch and the boss sleeve, where FIG. 7A shows a state before meshing and FIG. 7B shows a meshing state. ドリルモードの説明図で、（Ａ）がモード切替レバーの切替位置を、（Ｂ）が前ハウジング内をそれぞれ示す。In the explanatory view of the drill mode, (A) shows the switching position of the mode switching lever, and (B) shows the inside of the front housing. ハンマドリルモードの説明図で、（Ａ）がモード切替レバーの切替位置を、（Ｂ）が前ハウジング内をそれぞれ示す。It is explanatory drawing of a hammer drill mode, (A) shows the switching position of a mode switching lever, (B) shows the inside of a front housing, respectively. ハンマモードの説明図で、（Ａ）がモード切替レバーの切替位置を、（Ｂ）が前ハウジング内をそれぞれ示す。FIG. 3 is an explanatory view of a hammer mode, (A) shows the switching position of the mode switching lever, and (B) shows the inside of the front housing. 図５のＡ−Ａ線断面図である。It is the sectional view on the AA line of FIG. 図７のＢ−Ｂ線断面図である。FIG. 8 is a sectional view taken along line BB of FIG. 7. ハンマモードでのスライドプレートとモード切替レバーとの位置関係を示す説明図である。It is explanatory drawing which shows the positional relationship of the slide plate and mode switching lever in hammer mode.

以下、本発明の実施の形態を図面に基づいて説明する。
図１は、打撃工具でもあるハンマドリルの一例を示す全体図で、本体ハウジングでは、ブラシレスモータ及びスイッチを除いて内部を省略している。このハンマドリル１は、ブラシレスモータ３や図示しないコントローラ等を収容する本体ハウジング２の前側（図１の左側）上部に、出力部６を収容する先細り筒状の前ハウジング５を前向きに突設し、本体ハウジング２の後側上部で後述するツールホルダ１７の真後ろに当たる位置に、トリガ９を備えたスイッチ８を収容するハンドル７を設けてなる。１０は、本体ハウジング２の後側下部に装着されて電源となるバッテリーパックである。
ブラシレスモータ３は、本体ハウジング２内で回転軸４を上向きで且つ斜め後方へ向けた傾斜姿勢で収容されて、回転軸４の先端に設けた第１ギヤ（ベベルギヤ）１１を、前ハウジング５内に突出させている。 Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is an overall view showing an example of a hammer drill that is also a striking tool, and the inside of the main body housing is omitted except for a brushless motor and a switch. In this hammer drill 1, a tapered cylindrical front housing 5 for housing an output portion 6 is provided so as to project forward on the front side (left side in FIG. 1) of a main body housing 2 for housing a brushless motor 3 and a controller (not shown). A handle 7 for accommodating a switch 8 equipped with a trigger 9 is provided at a position on the upper rear side of the main body housing 2 and directly behind a tool holder 17 described later. Reference numeral 10 denotes a battery pack that is mounted on the lower rear side of the main body housing 2 and serves as a power source.
The brushless motor 3 is housed in the main body housing 2 in an inclined posture in which the rotary shaft 4 is directed upward and obliquely rearward, and the first gear (bevel gear) 11 provided at the tip of the rotary shaft 4 is installed in the front housing 5. Is projected.

前ハウジング５の内部には、インナハウジング１２が保持されている。このインナハウジング１２は、前ハウジング５の後端に嵌合して本体ハウジング２との間に組み付けられる長円皿状の後保持部１３と、その後保持部１３から前方へ突出する支持部１４と、支持部１４の前端にネジ止めされるリング状の前保持部１５とからなる。回転軸４の第１ギヤ１１は、後保持部１３に保持される軸受１６に軸支されて前ハウジング５内に突出している。
このインナハウジング１２の前方で前ハウジング５内には、筒状のツールホルダ１７と、その真下に位置する中間軸１８とが前後方向へ向けて収容されている。まず、ツールホルダ１７は、前ハウジング５の前部に設けた軸受１９と、インナハウジング１２の前保持部１５に圧入されるメタル軸受２０とによって回転可能且つ前後移動可能に軸支される。 An inner housing 12 is held inside the front housing 5. The inner housing 12 is fitted with a rear end of the front housing 5 and is assembled with the main body housing 2 in the form of an ellipse-shaped rear holding portion 13, and a supporting portion 14 that projects forward from the holding portion 13. , A ring-shaped front holding portion 15 screwed to the front end of the support portion 14. The first gear 11 of the rotating shaft 4 is axially supported by a bearing 16 held by the rear holding portion 13 and projects into the front housing 5.
In front of the inner housing 12 and inside the front housing 5, a cylindrical tool holder 17 and an intermediate shaft 18 located directly below the tool holder 17 are housed in the front-rear direction. First, the tool holder 17 is rotatably and movably supported by a bearing 19 provided in the front portion of the front housing 5 and a metal bearing 20 press-fitted into the front holding portion 15 of the inner housing 12.

ツールホルダ１７の後部外周には、フランジ２１が形成されてその後方には、ワッシャ２２を介して係止プレート２３と受けプレート２４とが重ねた状態で外装されている。ツールホルダ１７は、受けプレート２４と前保持部１５との間に外装したコイルバネ２５により、常態では前部外周に設けた止めリング２６が軸受１９に当接する前進位置へ突出付勢されている。ツールホルダ１７の後退は、受けプレート２４がメタル軸受２０に当接する図２の位置で規制される。受けプレート２４の下部側方には、図４に示すように、側面視が倒Ｌ字状となる規制板２７が一体に形成されている。 A flange 21 is formed on the outer periphery of the rear portion of the tool holder 17, and a locking plate 23 and a receiving plate 24 are provided behind the tool holder 17 in a stacked state with a washer 22 interposed therebetween. The tool holder 17 is normally biased by a coil spring 25 that is provided between the receiving plate 24 and the front holding portion 15 to a forward position where a retaining ring 26 provided on the outer circumference of the front portion contacts the bearing 19. The retracting of the tool holder 17 is restricted at the position of the receiving plate 24 in contact with the metal bearing 20 shown in FIG. As shown in FIG. 4, a regulation plate 27 having an inverted L-shape when viewed from the side is integrally formed on the lower side of the receiving plate 24.

また、ツールホルダ１７の外周において、フランジ２１と止めリング２６との間には、コイルバネ２８によってツールホルダ１７に設けたクラッチ板２９に押圧されることでツールホルダ１７と一体回転するトルクリミッタ付きの第４ギヤ３０が外装されている。
さらに、ツールホルダ１７の後側内部には、打撃部材としてのピストンシリンダ３１が前後移動可能に収容されている。このピストンシリンダ３１内には、空気室３２を介してストライカ３３が前後へ往復動可能に収容されている。ストライカ３３の前方には、インパクトボルト３４が収容されて、ツールホルダ１７の前端に挿入したビット３５の後端に当接可能となっている。ツールホルダ１７の前端には、ビット３５の着脱用の操作スリーブ３６が設けられている。 Further, on the outer periphery of the tool holder 17, between the flange 21 and the retaining ring 26, there is a torque limiter that rotates integrally with the tool holder 17 by being pressed by a clutch plate 29 provided on the tool holder 17 by a coil spring 28. The fourth gear 30 is exteriorly mounted.
Further, inside the rear side of the tool holder 17, a piston cylinder 31 as a striking member is housed so as to be movable back and forth. A striker 33 is reciprocally housed in the piston cylinder 31 via an air chamber 32. An impact bolt 34 is housed in front of the striker 33 and can come into contact with the rear end of a bit 35 inserted in the front end of the tool holder 17. An operating sleeve 36 for attaching and detaching the bit 35 is provided at the front end of the tool holder 17.

次に、中間軸１８は、前ハウジング５に設けた前軸受３７とインナハウジング１２の後保持部１３に設けた後軸受３８とによって回転可能に軸支されて、後部に設けた第２ギヤ（ベベルギヤ）３９を、回転軸４の第１ギヤ１１と噛合させている。第２ギヤ３９の前方で中間軸１８には、後方から、中間軸１８と別体で回転可能な変換部材としてのボススリーブ４０と、中間軸１８と一体回転するクラッチ４１とが外装されている。ボススリーブ４０は、軸線から傾斜させたスワッシュベアリング４２を有し、その外リング４３から放射方向上側に突設したアーム４４の先端を、ツールホルダ１７のピストンシリンダ３１の後端に連結している。ボススリーブ４０は、第２ギヤ３９との間に介在させたワッシャー４５に後方から係止して第２ギヤ３９との間のコイルバネ４６によってワッシャー４５へ押圧されるストッパリング４７により、後退位置が弾性的に規制されている。また、ボススリーブ４０の前面には、一対の凹部４８，４８が軸心を中心として点対称に形成されている。 Next, the intermediate shaft 18 is rotatably supported by the front bearing 37 provided on the front housing 5 and the rear bearing 38 provided on the rear holding portion 13 of the inner housing 12, and the second gear ( The bevel gear) 39 is meshed with the first gear 11 of the rotary shaft 4. A boss sleeve 40 as a conversion member that is rotatable separately from the intermediate shaft 18 and a clutch 41 that rotates integrally with the intermediate shaft 18 are externally mounted on the intermediate shaft 18 in front of the second gear 39 from the rear. .. The boss sleeve 40 has a swash bearing 42 that is inclined from the axis, and the tip of an arm 44 that projects radially upward from the outer ring 43 is connected to the rear end of the piston cylinder 31 of the tool holder 17. .. The boss sleeve 40 has a retracted position by a stopper ring 47 that is locked from behind by a washer 45 that is interposed between the boss sleeve 40 and the second gear 39 and is pressed against the washer 45 by a coil spring 46 between the boss sleeve 40 and the second gear 39. It is elastically regulated. In addition, a pair of recesses 48, 48 are formed on the front surface of the boss sleeve 40 in point symmetry about the axis.

クラッチ４１は、中間軸１８に形成されたスプライン部４９に結合されて、一体回転且つ軸方向へスライド可能となっているが、前端外周に設けた凹溝５０に、ツールホルダ１７に設けた係止プレート２３の外周が係止することで、ツールホルダ１７と連係して前後移動する。クラッチ４１の後面には、一対の凸部５１，５１が軸心を中心として点対称に形成されて、後方へのスライド位置（噛合位置）では、ボススリーブ４０の凹部４８，４８に嵌合してボススリーブ４０と噛み合い、前方へのスライド位置（非噛合位置）ではボススリーブ４０との噛み合いが解除される。
ここで、クラッチ４１の各凸部５１は、図３（Ａ）にも示すように、回転方向（周方向）の幅が根元側よりも先端側の方が広くなる逆テーパ状に形成されて、凸部５１の外側面に形成される噛み合い面５１ａを外向きに傾斜させている。この傾斜角度αは、放射方向外側から見て、中間軸１８の軸線と平行な直線Ｌに対して例えば５°〜２０°の範囲で設定されている。 The clutch 41 is coupled to a spline portion 49 formed on the intermediate shaft 18 so as to be integrally rotatable and slidable in the axial direction. However, the clutch 41 is provided in a groove 50 formed in the outer periphery of the front end and is provided in the tool holder 17. When the outer periphery of the stop plate 23 is locked, the stop plate 23 is moved back and forth in cooperation with the tool holder 17. On the rear surface of the clutch 41, a pair of convex portions 51, 51 are formed point-symmetrically with respect to the axial center, and are fitted into the concave portions 48, 48 of the boss sleeve 40 at the rearward sliding position (meshing position). Meshes with the boss sleeve 40, and the meshing with the boss sleeve 40 is released at the forward sliding position (non-meshing position).
Here, as shown in FIG. 3(A), each convex portion 51 of the clutch 41 is formed in an inverse taper shape in which the width in the rotation direction (circumferential direction) is wider on the tip side than on the root side. The meshing surface 51a formed on the outer surface of the convex portion 51 is inclined outward. The inclination angle α is set within a range of, for example, 5° to 20° with respect to the straight line L parallel to the axis of the intermediate shaft 18 when viewed from the outside in the radial direction.

これに対して、ボススリーブ４０の各凹部４８も、回転方向の幅が底部側よりも開放側の方が狭くなる逆テーパ状に形成されて、凹部４８の内側面に形成される噛み合い面４８ａを内向きに傾斜させている。この傾斜角度αの設定はクラッチ４１の凸部５１と同じである。
但し、ボススリーブ４０の前面では、クラッチ４１の凸部５１が前方に向かって左回転方向（図３（Ａ）の矢印方向）から噛み合うことから、各凹部４８における噛み合い面４８ａの逆側の内側面が浅くなる（低くなる）逃げ部５２が形成されている。 On the other hand, each recess 48 of the boss sleeve 40 is also formed in a reverse taper shape in which the width in the rotation direction is narrower on the open side than on the bottom side, and the meshing surface 48 a formed on the inner side surface of the recess 48. Is inclined inward. The setting of the inclination angle α is the same as that of the convex portion 51 of the clutch 41.
However, on the front surface of the boss sleeve 40, since the convex portion 51 of the clutch 41 meshes forward from the left rotation direction (the arrow direction in FIG. 3A), the inside of the concave portion 48 on the opposite side of the meshing surface 48a. An escape portion 52 whose side surface becomes shallow (low) is formed.

これにより、クラッチ４１が後退してボススリーブ４０と凹凸部４８，５１同士で噛み合った状態では、図３（Ｂ）に示すように、凸部５１の噛み合い面５１ａでは、凹部４８の噛み合い面４８ａとの前後両端の接触点のうち、根元側接触点（基端側接触点）Ｐ１よりも、先端側接触点Ｐ２の方が、回転方向で相手への噛み合い側（同図下側）にずれた状態となる。逆に、凹部４８の噛み合い面４８ａでは、凸部５１の噛み合い面５１ａとの前後両端の接触点のうち、底部側接触点（基端側接触点）Ｐ３よりも、開放側接触点（先端側接触点）Ｐ４の方が、回転方向で相手への噛み合い側（同図上側）にずれた状態となる。すなわち、互いに基端側接触点Ｐ１，Ｐ３よりも先端側接触点Ｐ２，Ｐ４の方が回転方向で相手への噛み合い側にずれた状態となる。このとき噛み合い面５１ａにおける根元側接触点Ｐ１と先端側接触点Ｐ２の間と、噛み合い面４８ａにおける底部側接触点Ｐ３と開放側接触点Ｐ４の間とは全面に亘って互いに当接している。よって、ボススリーブ４０とクラッチ４１との係合状態では、互いの離反方向で噛み合い面４８ａ，５１ａ同士が干渉して抵抗を生じさせることになる。 As a result, in a state where the clutch 41 retracts and meshes with the boss sleeve 40 and the concave and convex portions 48 and 51, as shown in FIG. 3B, the meshing surface 51 a of the convex portion 51 is the meshing surface 48 a of the concave portion 48. Of the contact points at the front and rear ends with and, the tip side contact point P2 is displaced to the mating side (lower side in the figure) in the rotational direction from the root side contact point (base end side contact point) P1. It will be in a state of being. On the contrary, in the meshing surface 48a of the concave portion 48, among the contact points of the front and rear ends with the meshing surface 51a of the convex portion 51, the open side contact point (tip side) is more than the bottom side contact point (base end side contact point) P3. The contact point) P4 is displaced toward the meshing side (upper side in the figure) with the partner in the rotation direction. That is, the tip end side contact points P2 and P4 are shifted from the base end side contact points P1 and P3 to the engagement side in the rotational direction. At this time, the root-side contact point P1 and the tip-side contact point P2 on the meshing surface 51a and the bottom-side contact point P3 and the open-side contact point P4 on the meshing surface 48a are in contact with each other over the entire surface. Therefore, when the boss sleeve 40 and the clutch 41 are engaged with each other, the meshing surfaces 48a and 51a interfere with each other in a direction in which they disengage from each other, causing resistance.

一方、中間軸１８におけるスプライン部４９の前方には、スプライン部４９より小径の小径部５３が形成され、この小径部５３に、本発明のギヤとしての第３ギヤ５４が回転可能に外装されて、ツールホルダ１７の第４ギヤ３０と噛合している。この第３ギヤ５４は、小径部５３の根元に設けた係合部としてのギヤ部５５に内周が噛合して中間軸１８と回転方向で一体となる図１，２の後退位置（係合位置（第１の状態））と、ギヤ部５５から離れて中間軸１８と回転方向で別体となる図６の前進位置（非係合位置（第２の状態））との間で前後移動可能となっている。第３ギヤ５４の外周には、リング状の係止溝５６が凹設されている。５７は、小径部５３の前部で前軸受３７の後面際に外装されたＯリングで、第３ギヤ５４を小径部５３に外装させてＯリング５７を取り付けることで、第３ギヤ５４の抜け止めとなり、前ハウジング５への組み付けがし易くなる。 On the other hand, a small diameter portion 53 having a smaller diameter than the spline portion 49 is formed in front of the spline portion 49 on the intermediate shaft 18, and a third gear 54 as a gear of the present invention is rotatably mounted on the small diameter portion 53. , Meshes with the fourth gear 30 of the tool holder 17. The third gear 54 has its inner periphery meshing with a gear portion 55 as an engaging portion provided at the base of the small diameter portion 53 so as to be integrated with the intermediate shaft 18 in the rotational direction (the engagement position shown in FIGS. 1 and 2). 6 is moved back and forth between the position (first state)) and the forward position (non-engagement position (second state)) of FIG. 6 which is separated from the gear portion 55 and separate from the intermediate shaft 18 in the rotational direction. It is possible. A ring-shaped locking groove 56 is provided on the outer periphery of the third gear 54. Reference numeral 57 denotes an O-ring that is mounted on the front portion of the small-diameter portion 53 and near the rear surface of the front bearing 37. The third gear 54 is mounted on the small-diameter portion 53 and the O-ring 57 is attached to remove the third gear 54. It becomes a stop, and it becomes easy to assemble to the front housing 5.

５８は、中間軸１８の側方に設けられて前後方向へ帯状に延びるスライド部材としてのスライドプレートで、図７，８に示すように、前端には中間軸１８側へ直角に折曲される係止片５９を有して第３ギヤ５４の係止溝５６に係止させている。また、スライドプレート５８の中間部位は、係止片５９と平行に中間軸１８側へ伸びる折り重ね部６０となっており、この折り重ね部６０と係止片５９とには、前軸受３７の側方で前ハウジング５内に突設したボス６１に前端が差し込み結合されて中間軸１８と平行に後方へ突出するガイド軸６２が貫通している。ガイド軸６２には、前端がボス６１に外装されて後端が係止片５９に当接する付勢手段としてのコイルバネ６３が外装されている。 Reference numeral 58 denotes a slide plate as a slide member which is provided on the side of the intermediate shaft 18 and extends in a belt shape in the front-rear direction. As shown in FIGS. 7 and 8, the front end is bent at a right angle toward the intermediate shaft 18 side. It has a locking piece 59 and is locked in the locking groove 56 of the third gear 54. Further, an intermediate portion of the slide plate 58 is a folded portion 60 extending toward the intermediate shaft 18 side in parallel with the locking piece 59, and the folded portion 60 and the locking piece 59 have the front bearing 37. A front end is inserted and coupled to a boss 61 projecting laterally in the front housing 5, and a guide shaft 62 protruding rearward in parallel with the intermediate shaft 18 penetrates therethrough. The guide shaft 62 is provided with a coil spring 63 as an urging means, the front end of which is externally attached to the boss 61 and the rear end of which is in contact with the locking piece 59.

よって、スライドプレート５８は常態で後方へ付勢されるが、その後退は、インナハウジング１２の後保持部１３の外周に設けたストッパ部６４（図４）に当接する位置で規制される。この後退位置では、係止片５９を介して同時に後退した第３ギヤ５４もギヤ部５５に噛合する後退位置となる。スライドプレート５８において、係止片５９と折り重ね部６０との間には、上方へ伸びてから後方へ折曲する逆Ｌ字状の当接片６５が形成されている。この当接片６５の後方への折曲部分は、受けプレート２４の規制板２７に外側から重なる位置となっている。 Therefore, the slide plate 58 is normally urged rearward, but its retreat is restricted at a position where it abuts on the stopper portion 64 (FIG. 4) provided on the outer periphery of the rear holding portion 13 of the inner housing 12. In this retracted position, the third gear 54 that has simultaneously retracted via the locking piece 59 is also in the retracted position where it meshes with the gear portion 55. In the slide plate 58, an inverted L-shaped contact piece 65 is formed between the locking piece 59 and the folding portion 60 and extends upward and then bends rearward. The rearward bent portion of the contact piece 65 is positioned so as to overlap the regulation plate 27 of the receiving plate 24 from the outside.

さらに、前ハウジング５の前側内面において、中間軸１８を挟んでガイド軸６２と反対側には、図７，８に示すように、ロック部材６６が設けられている。このロック部材６６は、前ハウジング５から中間軸１８と平行に立設される支持ピン６７に貫通支持されて、中間軸１８側に、前進位置の第３ギヤ５４と噛合する係止爪６８，６８を突設してなる。係止爪６８と反対側には、位置決め片６９が突設されて、この位置決め片６９が、前ハウジング５に設けたリブ７０，７０にガイドされることでロック部材６６の回転が規制される。また、位置決め片６９と前ハウジング５との間に設けたコイルバネ７１により、ロック部材６６は、支持ピン６７の先端のクリップ７２に当接する後退位置に付勢されている。すなわち、ロック部材６６、支持ピン６７、コイルバネ７１が、前進位置での第３ギヤ５４の回転を規制する回転規制手段となる。 Further, as shown in FIGS. 7 and 8, a lock member 66 is provided on the front inner surface of the front housing 5 on the side opposite to the guide shaft 62 with the intermediate shaft 18 interposed therebetween. The lock member 66 is penetratingly supported from the front housing 5 by a support pin 67 that is erected parallel to the intermediate shaft 18, and on the intermediate shaft 18 side, a locking claw 68 that meshes with the third gear 54 at the forward position. 68 is projected. A positioning piece 69 is provided on the opposite side of the locking claw 68, and the positioning piece 69 is guided by the ribs 70, 70 provided on the front housing 5, whereby the rotation of the lock member 66 is restricted. .. Further, the coil spring 71 provided between the positioning piece 69 and the front housing 5 urges the lock member 66 to the retracted position where it abuts on the clip 72 at the tip of the support pin 67. That is, the lock member 66, the support pin 67, and the coil spring 71 serve as rotation restricting means that restricts the rotation of the third gear 54 at the forward movement position.

そして、前ハウジング５の側面には、モード切替部材としてのモード切替レバー７３が設けられている。このモード切替レバー７３は、図７に示すように、前ハウジング５に形成した嵌合孔７４へ回転可能に嵌合する円盤状の回転部７５と、その回転部７５の外面で前ハウジング５の外部に露出するツマミ部７６とからなり、回転部７５には、回転中心から偏心した長短２本の第１偏心ピン７７と第２偏心ピン７８とが、中間軸１８側へ突設されている。このうち長い方の第１偏心ピン７７は、スライドプレート５８の上方で、スライドプレート５８の当接片６５及び受けプレート２４の規制板２７の後方から両プレート５８，２４を超えて前ハウジング５内に突出する長さとなっている。短い方の第２偏心ピン７８も、スライドプレート５８の上方で、当接片６５及び規制板２７の後方から前ハウジング５内に突出するが、先端は当接片６５と前後方向で干渉する位置にとどまり、規制板２７とは干渉しない長さとなっている。ここでは当接片６５の先端の延長線上に、第２偏心ピン７８の移動軌跡の上側が重なるようになっている。 A mode switching lever 73 as a mode switching member is provided on the side surface of the front housing 5. As shown in FIG. 7, the mode switching lever 73 has a disk-shaped rotating portion 75 that is rotatably fitted in a fitting hole 74 formed in the front housing 5, and an outer surface of the rotating portion 75 is provided on the front housing 5. The rotary portion 75 has a first eccentric pin 77 and a second eccentric pin 78, which are eccentric from the center of rotation and project toward the intermediate shaft 18 side. .. The first eccentric pin 77, which is the longer one of them, is located above the slide plate 58 and beyond the abutting piece 65 of the slide plate 58 and the regulating plate 27 of the receiving plate 24 beyond both plates 58 and 24 and inside the front housing 5. It has a protruding length. The shorter second eccentric pin 78 also projects above the slide plate 58 into the front housing 5 from the rear of the contact piece 65 and the regulation plate 27, but the tip end thereof is in a position where it interferes with the contact piece 65 in the front-rear direction. The length is such that it does not interfere with the regulation plate 27. Here, the upper side of the movement locus of the second eccentric pin 78 overlaps the extension line of the tip of the contact piece 65.

以上の如く構成されたハンマドリル１においては、モード切替レバー７３のツマミ部７６を把持して９０°ずつ回転部７５を回転させることで、第１、第２偏心ピン７７，７８を回転移動させ、受けプレート２４及び／又はスライドプレート５８に対するスライド規制又はその解除を行うことで、ドリルモード、ハンマドリルモード、ハンマモードの３つの動作モードが選択できる。なお、ツマミ部７６には、コイルバネ７９で突出付勢されるロックボタン８０が設けられて、モード切替レバー７３の回転に伴い、ロックボタン８０に設けられたピン８１が、前ハウジング５の外面に設けた円弧状のガイド溝８２内に沿って移動する。対応する動作モードの位置では、ピン８１がガイド溝８２の外側に設けた係止部８３に係止して動作モードを維持する。以下、各動作モードについて説明する。 In the hammer drill 1 configured as described above, by gripping the knob portion 76 of the mode switching lever 73 and rotating the rotating portion 75 by 90°, the first and second eccentric pins 77 and 78 are rotationally moved, By restricting or releasing the slide on the receiving plate 24 and/or the slide plate 58, three operation modes of a drill mode, a hammer drill mode, and a hammer mode can be selected. It should be noted that the knob portion 76 is provided with a lock button 80 biased by a coil spring 79 so that the pin 81 provided on the lock button 80 is provided on the outer surface of the front housing 5 as the mode switching lever 73 rotates. It moves along the arc-shaped guide groove 82 provided. At the position of the corresponding operation mode, the pin 81 engages with the engaging portion 83 provided outside the guide groove 82 to maintain the operation mode. Hereinafter, each operation mode will be described.

まず、ツマミ部７６を後向きに倒したモード切替レバー７３の回転位置では、図４に示すように、第１偏心ピン７７が回転部７５の回転中心Ｏよりも前側、第２偏心ピン７８が回転中心Ｏよりも後側に位置し、第１偏心ピン７７は、ツールホルダ１７と共に前進位置にある受けプレート２４の規制板２７の後縁に近接している。このときスライドプレート５８は、ストッパ部６４に当接して第３ギヤ５４をギヤ部５５に噛合させる後退位置にある。
よって、ツールホルダ１７の後退は受けプレート２４の規制板２７を介して第１偏心ピン７７により規制され、クラッチ４１がボススリーブ４０から離れる前進位置が維持されて、第３ギヤ５４が中間軸１８と結合されるドリルモードとなる。 First, at the rotational position of the mode switching lever 73 in which the knob portion 76 is tilted backward, as shown in FIG. 4, the first eccentric pin 77 rotates forward of the rotation center O of the rotating portion 75 and the second eccentric pin 78 rotates. The first eccentric pin 77, which is located on the rear side of the center O, is close to the rear edge of the regulation plate 27 of the receiving plate 24 that is in the forward movement position together with the tool holder 17. At this time, the slide plate 58 is in the retracted position where it abuts on the stopper portion 64 and meshes the third gear 54 with the gear portion 55.
Therefore, the retreat of the tool holder 17 is restricted by the first eccentric pin 77 via the restriction plate 27 of the receiving plate 24, the forward position where the clutch 41 is separated from the boss sleeve 40 is maintained, and the third gear 54 is moved by the intermediate shaft 18. The drill mode is combined with.

この状態でトリガ９を押し込んでスイッチ８をＯＮさせ、ブラシレスモータ３を駆動させると、回転軸４が回転し、第１ギヤ１１を介して第２ギヤ３９から中間軸１８を減速して回転させる。このときクラッチ４１及び第３ギヤ５４が一体に回転するが、クラッチ４１はボススリーブ４０と噛み合わないため、ボススリーブ４０は回転せず、ピストンシリンダ３１は動作しない。よって、第３ギヤ５４の回転が第４ギヤ３０を介してツールホルダ１７に伝わり、ビット３５を回転させる。ビット３５を被削材に押し当ててツールホルダ１７を押し込んでも、受けプレート２７の後退が規制されているため、ドリルモードは維持される。 When the trigger 9 is pushed in this state to turn on the switch 8 and drive the brushless motor 3, the rotating shaft 4 rotates, and the intermediate shaft 18 is decelerated from the second gear 39 via the first gear 11 to rotate. .. At this time, the clutch 41 and the third gear 54 rotate integrally, but since the clutch 41 does not mesh with the boss sleeve 40, the boss sleeve 40 does not rotate and the piston cylinder 31 does not operate. Therefore, the rotation of the third gear 54 is transmitted to the tool holder 17 via the fourth gear 30, and the bit 35 is rotated. Even if the bit 35 is pressed against the work material and the tool holder 17 is pushed in, the backward movement of the receiving plate 27 is restricted, so that the drill mode is maintained.

次に、ツマミ部７６を上向きに９０°回転させたモード切替レバー７３の回転位置では、図５に示すように、第１偏心ピン７７は回転部７５の回転中心Ｏの下側に位置して受けプレート２４の規制板２７から後方へ離れ、第２偏心ピン７８は、回転中心Ｏの上側へ移動して当接片６５の先端に近接している。スライドプレート５８の後退位置は変わらない。
よって、ツールホルダ１７の後退が第１偏心ピン７７によって規制されず、クラッチ４１と共に後退位置まで移動できるハンマドリルモードとなる。すなわち、ビット３５を被削材に押し当ててツールホルダ１７を前ハウジング５内へ押し込むと、ツールホルダ１７と共に後退したクラッチ４１の凸部５１，５１がボススリーブ４０の凹部４８，４８に噛み合い、クラッチ４１の回転がボススリーブ４０に伝達される。第３ギヤ５４と第４ギヤ３０との噛合状態は変わらない。
この状態で中間軸１８が回転すると、クラッチ４１の回転がボススリーブ４０へ伝わり、スワッシュベアリング４２によってアーム４４が前後へ揺動してピストンシリンダ３１を前後移動させる。よって、空気室３２を介してストライカ３３が連動して往復動し、インパクトボルト３４を介してビット３５を間接的に打撃する。同時にツールホルダ１７が回転してビット３５を回転させる。 Next, at the rotational position of the mode switching lever 73 in which the knob portion 76 is rotated upward by 90°, the first eccentric pin 77 is positioned below the rotation center O of the rotating portion 75, as shown in FIG. The second eccentric pin 78 moves to the upper side of the center of rotation O and is close to the tip of the contact piece 65 while being separated rearward from the regulation plate 27 of the receiving plate 24. The retracted position of the slide plate 58 does not change.
Therefore, the retreat of the tool holder 17 is not restricted by the first eccentric pin 77, and the hammer drill mode in which the tool holder 17 can move to the retracted position together with the clutch 41 is set. That is, when the tool holder 17 is pushed into the front housing 5 by pressing the bit 35 against the work material, the convex portions 51, 51 of the clutch 41 retracted together with the tool holder 17 mesh with the concave portions 48, 48 of the boss sleeve 40, The rotation of the clutch 41 is transmitted to the boss sleeve 40. The meshing state of the third gear 54 and the fourth gear 30 does not change.
When the intermediate shaft 18 rotates in this state, the rotation of the clutch 41 is transmitted to the boss sleeve 40, and the swash bearing 42 swings the arm 44 back and forth to move the piston cylinder 31 back and forth. Therefore, the striker 33 reciprocates in conjunction with the air chamber 32, and indirectly hits the bit 35 via the impact bolt 34. At the same time, the tool holder 17 rotates to rotate the bit 35.

このハンマドリルモードで使用している際、地面等へのビット３５の押し込み力が弱くなってツールホルダ１７の押し荷重が低下することがあっても、図３（Ｂ）のようにクラッチ４１の凸部５１，５１とボススリーブ４０の凹部４８，４８とは互いに傾斜した噛み合い面５１ａ，４８ａ同士の当接によって離反方向へ抵抗が生じているため、コイルバネ２５の付勢に抗してツールホルダ１７及びクラッチ４１の前進が規制され、クラッチ４１とボススリーブ４０との係合は維持される。よって、作業中に打撃動作が中断することは生じにくくなる。 When the hammer 35 is used in the hammer drill mode, even if the pushing force of the bit 35 onto the ground or the like is weakened and the pushing load of the tool holder 17 is reduced, as shown in FIG. Since the portions 51, 51 and the recesses 48, 48 of the boss sleeve 40 contact each other with the inclining meshing surfaces 51a, 48a, resistance is generated in the separating direction, so that the tool holder 17 is resisted against the bias of the coil spring 25. The forward movement of the clutch 41 is restricted, and the engagement between the clutch 41 and the boss sleeve 40 is maintained. Therefore, the striking operation is unlikely to be interrupted during the work.

次に、ツマミ部７６を前向きに９０°回転させたモード切替レバー７３の回転位置では、図６に示すように、第１偏心ピン７７が回転中心Ｏの後側に位置し、第２偏心ピン７８は回転中心Ｏの前側に位置して、図９にも示すように当接片６５を介してスライドプレート５８をコイルバネ６３の付勢に抗して前進位置へ移動させる。
よって、ツールホルダ１７の後退が規制されず、クラッチ４１と共に後退位置まで移動できるが、スライドプレート５８と共に前進位置へ移動した第３ギヤ５４がギヤ部５５から離れるため、中間軸１８の回転が伝達されないハンマモードとなる。すなわち、ツールホルダ１７を押し込んだ状態で中間軸１８が回転すると、クラッチ４１の回転がボススリーブ４０へ伝わり、ピストンシリンダ３１を前後移動させてストライカ３３を往復動させ、インパクトボルト３４を介してビット３５を打撃するが、ギヤ部５５から離れた第３ギヤ５４は回転しないため、ツールホルダ１７は回転しない。 Next, at the rotational position of the mode switching lever 73 where the knob portion 76 is rotated forward by 90°, as shown in FIG. 6, the first eccentric pin 77 is located on the rear side of the rotation center O and the second eccentric pin 77 is located. 78 is located on the front side of the center of rotation O and moves the slide plate 58 to the forward position against the bias of the coil spring 63 via the contact piece 65 as shown in FIG.
Therefore, although the backward movement of the tool holder 17 is not restricted and the tool holder 17 can move to the backward position together with the clutch 41, the rotation of the intermediate shaft 18 is transmitted because the third gear 54 that has moved to the forward position together with the slide plate 58 separates from the gear portion 55. It becomes a hammer mode that is not done. That is, when the intermediate shaft 18 rotates while the tool holder 17 is pushed in, the rotation of the clutch 41 is transmitted to the boss sleeve 40, the piston cylinder 31 is moved back and forth, the striker 33 is reciprocally moved, and the bit is passed through the impact bolt 34. Although the tool 35 is struck, the tool holder 17 does not rotate because the third gear 54 separated from the gear portion 55 does not rotate.

このハンマモードにおいても、ツールホルダ１７の押し荷重が低下することがあっても、図３（Ｂ）のようにクラッチ４１の凸部５１，５１とボススリーブ４０の凹部４８，４８とは互いに傾斜した噛み合い面５１ａ，４８ａ同士の当接によって離反方向へ抵抗が生じている。よって、クラッチ４１とボススリーブ４０との係合は維持され、打撃動作の中断は生じにくくなる。
また、第３ギヤ５４は、前進位置ではロック部材６６の係止爪６８が係止することで回転が規制されるため、第４ギヤ３０を介してツールホルダ１７の回転もロックされる。よって、ハンマモードへ切り替える際にタガネ等のビット３５の角度を使いやすい角度にしておけば、そのままロックして使用できる。なお、第３ギヤ５４が前進した際、ロック部材６６の係止爪６８がうまく係止しない場合、ロック部材６６をコイルバネ７１の付勢に抗して前方へ押し込んだ状態となるが、ビット３５を介してツールホルダ１７を回転させれば、第４ギヤ３０を介して第３ギヤ５４が回転し、係止爪６８が係止する位置でロック部材６６が前進位置へ復帰してロックされる。 Even in the hammer mode, even if the pushing load of the tool holder 17 is reduced, the convex portions 51, 51 of the clutch 41 and the concave portions 48, 48 of the boss sleeve 40 are inclined to each other as shown in FIG. 3B. The contact between the meshing surfaces 51a and 48a causes resistance in the separating direction. Therefore, the engagement between the clutch 41 and the boss sleeve 40 is maintained, and the impact operation is less likely to be interrupted.
Further, since the rotation of the third gear 54 is restricted by the locking claw 68 of the lock member 66 being locked at the forward position, the rotation of the tool holder 17 is also locked via the fourth gear 30. Therefore, if the angle of the bit 35 such as chisel is set to an easy-to-use angle when switching to the hammer mode, it can be locked and used as it is. If the locking claw 68 of the lock member 66 does not lock properly when the third gear 54 moves forward, the lock member 66 is pushed forward against the bias of the coil spring 71. When the tool holder 17 is rotated via the fourth gear 30, the third gear 54 is rotated via the fourth gear 30, and the locking member 66 is returned to the forward position and locked at the position where the locking claw 68 is locked. ..

このように、上記形態のハンマドリル１によれば、第３ギヤ５４が、中間軸１８の回転が伝達される第１の状態（中間軸１８との係合位置）と、中間軸１８の回転が伝達されない第２の状態（中間軸１８との非係合位置）とに切替可能に設けられると共に、第３ギヤ５４の状態を前ハウジング５の外部から切替操作可能なモード切替レバー７３が設けられて、モード切替レバー７３による第３ギヤ５４の状態の切替により、第３ギヤ５４が中間軸１８と一体回転してツールホルダ１７に回転とピストンシリンダ３１の往復動とを生じさせるハンマドリルモードと、第３ギヤ５４が中間軸１８の回転と切り離されてピストンシリンダ３１の往復動のみを生じさせるハンマモードとの少なくとも２つの動作モードが選択可能となっている。
これにより、前方へ突出付勢されるツールホルダ１７の前後位置によって動作モードを選択可能とする小型のハンマドリル１であっても、ハンマモードを選択でき、さらなる使い勝手の向上が期待できる。
また、第３ギヤ５４を、中間軸１８と係合して一体回転する係合位置と、中間軸１８との係合が解除される非係合位置との間でスライドすることで第１の状態と第２の状態とに切替可能として、モード切替レバー７３を、第３ギヤ５４のスライド位置を前ハウジング５の外部から切替操作するものとしているので、第３ギヤ５４のスライドによって中間軸１８からの回転伝達の切替が容易に行える。 As described above, according to the hammer drill 1 of the above-described embodiment, the rotation of the intermediate shaft 18 is prevented when the third gear 54 is in the first state (engagement position with the intermediate shaft 18) where the rotation of the intermediate shaft 18 is transmitted. A mode switching lever 73 is provided which is switchable to a second state where it is not transmitted (a non-engagement position with the intermediate shaft 18) and which can switch the state of the third gear 54 from the outside of the front housing 5. Then, by switching the state of the third gear 54 by the mode switching lever 73, the hammer drill mode in which the third gear 54 rotates integrally with the intermediate shaft 18 to cause the tool holder 17 to rotate and the piston cylinder 31 to reciprocate, At least two operation modes, which are the hammer mode in which the third gear 54 is separated from the rotation of the intermediate shaft 18 to cause only the reciprocating motion of the piston cylinder 31, can be selected.
As a result, even with a small hammer drill 1 that can select an operation mode depending on the front and rear position of the tool holder 17 that is biased to project forward, the hammer mode can be selected, and further improvement in usability can be expected.
In addition, by sliding the third gear 54 between an engagement position in which the third shaft 54 is engaged with the intermediate shaft 18 and integrally rotates, and a non-engaged position in which the engagement with the intermediate shaft 18 is released, the first gear 54 is slid. Since the state can be switched between the second state and the second state, the mode switching lever 73 is operated to switch the slide position of the third gear 54 from outside the front housing 5, so that the intermediate shaft 18 can be moved by sliding the third gear 54. The rotation transmission from can be easily switched.

特にここでは、モード切替レバー７３は、クラッチ４１のスライド位置を、ボススリーブ４０と噛合して一体回転させる噛合位置と、ボススリーブ４０との噛合が解除される非噛合位置とに切替可能であり、第３ギヤ５４の係合位置とクラッチ４１の非噛合位置との切替によって、第３ギヤ５４が中間軸１８と一体回転してツールホルダ１７に回転のみ生じさせるドリルモードがさらに選択可能であるので、３つの動作モードが使用でき、作業の幅が広がる。
また、第３ギヤ５４の非係合位置で第３ギヤ５４の回転を規制する回転規制手段（ロック部材６６、支持ピン６７、コイルバネ７１）が設けられていることで、ハンマモードでのビット３５の回転をロックでき、ハツリ作業等がしやすくなる。 In particular, here, the mode switching lever 73 is capable of switching the sliding position of the clutch 41 between a meshing position in which the clutch 41 meshes with the boss sleeve 40 and integrally rotates, and a non-meshing position in which the meshing with the boss sleeve 40 is released. By switching the engagement position of the third gear 54 and the non-engagement position of the clutch 41, it is possible to further select a drill mode in which the third gear 54 rotates integrally with the intermediate shaft 18 and causes the tool holder 17 to rotate only. Therefore, three operation modes can be used, and the range of work is expanded.
Further, since the rotation restricting means (lock member 66, support pin 67, coil spring 71) for restricting the rotation of the third gear 54 at the non-engaging position of the third gear 54 is provided, the bit 35 in the hammer mode is provided. The rotation of can be locked, making it easier to carry out chiseling work.

さらに、前ハウジング５内に、中間軸１８と平行に支持されるガイド軸６２と、第３ギヤ５４に係止してガイド軸６２に沿って前後移動可能なスライドプレート５８と、スライドプレート５８を第３ギヤ５４の係合位置へ付勢するコイルバネ６３とが設けられ、モード切替レバー７３の切替操作に伴い、スライドプレート５８がコイルバネ６３の反付勢方向へ移動することで第３ギヤ５４が非係合位置へスライドすることで、第３ギヤ５４のスライド位置の切替がスムーズに行える。
加えて、モード切替レバー７３を、２つの第１、第２偏心ピン７７，７８を備えて回転操作するものとして、当該回転操作に伴い第２偏心ピン７８がスライドプレート５８を反付勢方向へ移動させるので、１つのモード切替レバー７３の操作によってハンマモードの選択も行える。 Further, in the front housing 5, there are provided a guide shaft 62 which is supported in parallel with the intermediate shaft 18, a slide plate 58 which is engaged with the third gear 54 and is movable back and forth along the guide shaft 62. A coil spring 63 that urges the third gear 54 to the engagement position is provided, and the slide plate 58 moves in the opposite urging direction of the coil spring 63 in accordance with the switching operation of the mode switching lever 73. The sliding position of the third gear 54 can be smoothly switched by sliding to the non-engagement position.
In addition, assuming that the mode switching lever 73 is provided with the two first and second eccentric pins 77 and 78 for rotational operation, the second eccentric pin 78 causes the slide plate 58 in the anti-biasing direction along with the rotational operation. Since it is moved, the hammer mode can be selected by operating one mode switching lever 73.

そして、中間軸１８の前端に、ボススリーブ４０の設置側よりも小径となる小径部５３を形成して第３ギヤ５４を小径部５３に外装し、係合位置では小径部５３の根元に設けたギヤ部５５と係合させて中間軸１８と一体回転させているので、第３ギヤ５４を小型化でき、省スペース化に繋がる。
また、ブラシレスモータ３は、本体ハウジング２内における中間軸１８の下側で、回転軸４の軸線が中間軸１８と交差する向きで配置されて、ツールホルダ１７の後方にはハンドル７が設けられることで、前後方向の寸法をコンパクト化できると共に、ツールホルダ１７の真後ろに設けたハンドル７によって押し荷重もロスなく加えることができる。 Then, a small diameter portion 53 having a diameter smaller than that of the installation side of the boss sleeve 40 is formed at the front end of the intermediate shaft 18, and the third gear 54 is exteriorly mounted on the small diameter portion 53, and provided at the base of the small diameter portion 53 at the engagement position. Since the third gear 54 is engaged with the gear portion 55 and integrally rotated with the intermediate shaft 18, the third gear 54 can be downsized, which leads to space saving.
Further, the brushless motor 3 is arranged below the intermediate shaft 18 in the main body housing 2 so that the axis of the rotary shaft 4 intersects with the intermediate shaft 18, and a handle 7 is provided behind the tool holder 17. As a result, the dimension in the front-rear direction can be made compact, and the pushing load can be applied without loss by the handle 7 provided directly behind the tool holder 17.

なお、ハンマモードを選択可能とする発明において、受けプレートやスライドプレート、回転規制手段の構造は上記形態に限らず、規制板や当接片の形状を変えたり、スライドプレートをガイド軸でなくハウジングの内面に設けたリブ等でガイドしたり等、適宜変更可能である。回転規制手段は省略することもできる。
また、上記形態では、クラッチをボススリーブ等の変換部材に係脱させて打撃作動を選択できるようにしているが、クラッチがなく、変換部材が中間軸と一体回転するものであって、回転伝達用のギヤのスライド位置を切り替えることで、ハンマモードとハンマドリルモードとの２つの動作モードが選択できるハンマドリルであっても差し支えない。
さらに、上記形態ではギヤ（第３ギヤ）をスライドさせることで中間軸からの回転伝達を切り替えるようにしているが、ギヤをスライドさせずに中間軸に対して回転フリー状態で設けると共に、中間軸に、一体回転可能且つ軸方向へスライド可能なクラッチ部材を設けて、このクラッチ部材をモード切替部材によってギヤに対して係脱させることで中間軸からの回転伝達を切り替えるようにすることも可能である。 In the invention in which the hammer mode can be selected, the structure of the receiving plate, the slide plate, and the rotation restricting means is not limited to the above-described form, and the shape of the restricting plate or the contact piece may be changed, or the slide plate may be used instead of the guide shaft in the housing. It can be appropriately changed by guiding with a rib or the like provided on the inner surface of the. The rotation restricting means can be omitted.
Further, in the above-described embodiment, the clutch is engaged with and disengaged from the conversion member such as the boss sleeve so that the striking operation can be selected, but the conversion member rotates integrally with the intermediate shaft without the clutch, and the rotation transmission is performed. It is possible to use a hammer drill in which two operation modes, a hammer mode and a hammer drill mode, can be selected by switching the sliding position of the gear for use.
Further, in the above embodiment, the rotation transmission from the intermediate shaft is switched by sliding the gear (third gear). However, the gear is not slid and the rotation transmission is provided with respect to the intermediate shaft. It is also possible to switch the rotation transmission from the intermediate shaft by providing an integrally rotatable clutch member that is slidable in the axial direction and engaging and disengaging this clutch member with respect to the gear by the mode switching member. is there.

一方、上記形態のハンマドリル１によれば、凸部５１及び凹部４８との互いの噛み合い面５１ａ，４８ａが、自身に近い側で相手側の噛み合い面と接触する基端側接触点Ｐ１，Ｐ３よりも、自身から遠い側で相手側の噛み合い面と接触する先端側接触点Ｐ２，Ｐ４の方が、回転方向で相手との噛み合い側にずれる形状をそれぞれ含んでおり、凸部５１と凹部４８との噛み合い状態では、互いの噛み合い面５１ａ，４８ａ同士の干渉によってボススリーブ４０とクラッチ４１との離反方向への抵抗を生じさせるようになっている。
これにより、前方へ突出付勢されるツールホルダ１７と共に後退したクラッチ４１がボススリーブ４０に係合することでハンマドリルモードやハンマモードを選択可能としたものであっても、ボススリーブ４０へのクラッチ４１の係合が外れにくくなり、良好な作業性が維持できる。 On the other hand, according to the hammer drill 1 of the above-described embodiment, the meshing surfaces 51a, 48a of the convex portion 51 and the concave portion 48 with respect to each other are closer to the meshing surface of the other side than the proximal contact points P1, P3. Also, the tip end side contact points P2 and P4 that come into contact with the mating surface of the mating side on the side far from itself include shapes that are displaced toward the mating side with the mating side in the rotational direction, and the convex portion 51 and the concave portion 48 are formed. In the meshed state, the meshing surfaces 51a and 48a interfere with each other to generate resistance in the direction in which the boss sleeve 40 and the clutch 41 separate from each other.
As a result, even if the clutch 41 that has retracted together with the tool holder 17 that is biased to project forward is engaged with the boss sleeve 40 to enable the hammer drill mode or the hammer mode to be selected, the clutch for the boss sleeve 40 is not included. The engagement of 41 is less likely to come off, and good workability can be maintained.

特にここでは、凸部５１と凹部４８との噛み合い状態では、互いの噛み合い面５１ａ，４８ａにおける基端側接触点Ｐ１（Ｐ３）と先端側接触点Ｐ２（Ｐ４）との間の全面同士が互いに当接しているので、離反方向での噛み合い面５１ａ，４８ａ同士の干渉が大きくなって、クラッチ４１の係合がより外れにくくなる。
また、凸部５１は、根元側よりも先端側の方が回転方向の幅が広く形成されて傾斜する外側面が噛み合い面５１ａとなる逆テーパ形状であり、凹部４８は、底部側よりも開放側の方が回転方向の幅が狭く形成されて傾斜する内側面が噛み合い面４８ａとなる逆テーパ形状であるので、係合が外れにくい噛み合い面５１ａ，４８ａが簡単に形成できる。 In particular, here, in the meshing state of the convex portion 51 and the concave portion 48, the entire surfaces between the proximal end side contact point P1 (P3) and the distal end side contact point P2 (P4) on the meshing surfaces 51a and 48a are mutually mutually. Since they are in contact with each other, the interference between the meshing surfaces 51a and 48a in the disengagement direction becomes large, and the engagement of the clutch 41 becomes more difficult to disengage.
Further, the convex portion 51 has an inverted taper shape in which the width of the tip end side is wider in the rotational direction than the root side and the inclined outer side surface is the meshing surface 51a, and the concave portion 48 is open more than the bottom side. Since the side has a reverse taper shape in which the width in the rotation direction is narrower and the inclined inner side surface is the meshing surface 48a, the meshing surfaces 51a and 48a that are difficult to disengage can be easily formed.

さらに、凸部５１及び凹部４８の両噛み合い面５１ａ，４８ａの傾斜角度を、中間軸１８の軸線と平行な直線Ｌに対して５°〜２０°の範囲内としているので、噛み合いやすく外れにくい噛み合い面５１ａ，４８ａが設定可能となる。
加えて、凹部４８が形成されるボススリーブ４０の端面には、凸部５１との噛み合い面４８ａの反対側の内側面が当該噛み合い面４８ａよりも浅くなる逃げ部５２が形成されているので、凸部５１が凹部４８に進入しやすくなって噛み合いがスムーズになされる。 Furthermore, since the angle of inclination of the meshing surfaces 51a and 48a of the convex portion 51 and the concave portion 48 is within the range of 5° to 20° with respect to the straight line L parallel to the axis of the intermediate shaft 18, the meshing is easy and the meshing is difficult to disengage. The surfaces 51a and 48a can be set.
In addition, at the end surface of the boss sleeve 40 in which the concave portion 48 is formed, since the inner surface on the side opposite to the meshing surface 48a with the convex portion 51 is formed with a relief portion 52 that is shallower than the meshing surface 48a, The convex portion 51 easily enters the concave portion 48, and the meshing is smoothly performed.

なお、凸部と凹部との形状に係る発明において、凹凸部の数は上記形態に限らず、３つ以上設けてもよいし、両側面が傾斜する逆テーパでなく、噛み合い側の面のみを傾斜させてもよい。
また、上記形態では、凹凸部の噛み合い面を傾斜平面としているが、凹凸部の一方の噛み合い面を円弧状に膨らむ凸曲面、他方の噛み合い面を当該膨出部が嵌合する凹曲面とすることもできる。
さらに、噛み合い面の全面を傾斜平面や曲面にする必要はなく、例えば凸部では根元側を同幅とし、先端側を逆テーパにして、これに対応する凹部を、底部側を逆テーパにし、開放側を同幅とすることも考えられる。すなわち、凹凸部の側面の一部に離反方向で干渉が生じる噛み合い面を形成しても差し支えない。従って、根元側半分が傾斜平面や曲面となって先端側半分が先細りとなるような凸部とこれに嵌合する凹部とであっても、凸部の根元側と凹部の開放側とで離反方向に干渉は生じることになる。 In the invention relating to the shapes of the convex portion and the concave portion, the number of the concave and convex portions is not limited to the above-mentioned form, and three or more may be provided, or only the meshing side surface may be provided instead of the reverse taper in which both side surfaces are inclined. You may incline.
Further, in the above embodiment, the meshing surface of the uneven portion is an inclined plane, but one meshing surface of the uneven portion is a convex curved surface that bulges in an arc shape, and the other meshing surface is a concave curved surface to which the bulging portion fits. You can also
Further, it is not necessary to make the entire meshing surface into an inclined flat surface or a curved surface. For example, in the convex portion, the base side is the same width, the tip side is inversely tapered, and the corresponding concave portion is inversely tapered on the bottom side. It is also possible to make the open side the same width. That is, it is possible to form a meshing surface that causes interference in a separating direction on a part of the side surface of the uneven portion. Therefore, even if the convex portion is such that the root half is an inclined flat surface or a curved surface and the tip half is tapered and the concave portion that fits into this convex portion, the root side of the convex portion and the open side of the concave portion are separated from each other. Interference will occur in the direction.

そして、上記形態では、第３ギヤをスライドさせてハンマモードも選択できるようにしているが、第３ギヤがスライドせず、ツールホルダとクラッチとの前後移動によってドリルモードとハンマドリルモードとの２つの動作モードのみが選択できるハンマドリル等の他の打撃工具であっても、凸部と凹部との形状に係る本発明は採用可能である。 In the above embodiment, the third gear is slid so that the hammer mode can also be selected. However, the third gear does not slide, and the tool holder and the clutch move back and forth to provide two modes, a drill mode and a hammer drill mode. The present invention relating to the shapes of the convex portion and the concave portion can be applied to other hammering tools such as a hammer drill in which only the operation mode can be selected.

１・・ハンマドリル、２・・本体ハウジング、３・・ブラシレスモータ、４・・回転軸、５・・前ハウジング、６・・出力部、７・・ハンドル、１１・・第１ギヤ、１２・・インナハウジング、１７・・ツールホルダ、１８・・中間軸、２３・・係止プレート、２４・・受けプレート、２５・・コイルバネ、２７・・規制板、３０・・第４ギヤ、３１・・ピストンシリンダ、３３・・ストライカ、３５・・ビット、３９・・第２ギヤ、４０・・ボススリーブ、４１・・クラッチ、４８・・凹部、４８ａ，５１ａ・・噛み合い面、４９・・スプライン部、５１・・凸部、５２・・逃げ部、５３・・小径部、５４・・第３ギヤ、５５・・ギヤ部、５８・・スライドプレート、５９・・係止片、６２・・ガイド軸、６５・・当接片、６６・・ロック部材、６７・・支持ピン、７３・・モード切替レバー、７５・・回転部、７６・・ツマミ部、７７・・第１偏心ピン、７８・・第２偏心ピン、Ｐ１・・根元側接触点、Ｐ２・・先端側接触点、Ｐ３・・底部側接触点、Ｐ４・・開放側接触点。 1... Hammer drill, 2... Main body housing, 3... Brushless motor, 4... Rotating shaft, 5... Front housing, 6... Output section, 7... Handle, 11... First gear, 12... Inner housing, 17・・Tool holder, 18・・Intermediate shaft, 23・・Locking plate, 24・・Reception plate, 25・・Coil spring, 27・・Regulator plate, 30・・4th gear, 31・・Piston Cylinder, 33, striker, 35, bit, 39, second gear, 40, boss sleeve, 41, clutch, 48, recess, 48a, 51a, meshing surface, 49, spline portion, 51 ..Convex part, 52..Escape part, 53..Small diameter part, 54..Third gear, 55..gear part, 58..slide plate, 59..locking piece, 62..guide shaft, 65 ..Abutting pieces, 66..Locking members, 67..Supporting pins, 73..Mode switching lever, 75..rotating part, 76..knob part, 77..first eccentric pin, 78..second Eccentric pin, P1... Root contact point, P2... Tip contact point, P3... Bottom contact point, P4... Open contact point.

Claims

A housing for housing the motor,
A tool holder capable of holding a tip tool, movable forward and backward in the housing, and provided with a biasing force projecting forward;
A striking member provided to be movable back and forth in the tool holder,
An intermediate shaft that is provided in the housing in parallel with the tool holder and transmits the rotation of the motor,
A gear that is provided on the intermediate shaft and transmits the rotation of the intermediate shaft to the tool holder;
A hammer drill comprising a conversion member provided on the intermediate shaft and converting the rotation of the intermediate shaft into the reciprocating motion of the striking member,
A retracted position, which is provided so as to be integrally rotatable with the intermediate shaft and slidable in the axial direction, and which is linked to the back-and-forth movement of the tool holder, and which is meshed with the conversion member, and a forward position, in which the meshing with the conversion member is released. Further including a clutch that moves back and forth between
The rear engagement position where the gear engages with the intermediate shaft and integrally rotates with the intermediate shaft, and the front non-engagement position where the rotation of the intermediate shaft is not transmitted because the engagement with the intermediate shaft is released. It is slidable back and forth between the mating position,
The tool holder is provided with a regulation member that moves back and forth integrally with the tool holder,
A guide shaft that is supported in parallel with the intermediate shaft in the housing, a slide member that is locked to the gear and is movable back and forth along the guide shaft, and the slide member that engages the gear at the engagement position. Urging means for urging to,
A mode switching member that includes two eccentric pins and that can switch the front-rear position of the restriction member and the front-rear position of the slide member from the outside of the housing by a rotation operation is provided.
By rotating the mode switching member ,
The one eccentric pin is in a position that regulates the retreat of the regulating member to maintain the tool holder and the clutch in the forward position, and the other eccentric pin allows the retreat of the slide member to allow the gear to move. In a position to slide to the engaging position, the drill mode in which the gear rotates integrally with the intermediate shaft and causes only rotation in the tool holder,
The one eccentric pin is at a position allowing the retreat of the restriction member, the tool holder and the clutch, and the other eccentric pin allows the retreat of the slide member to slide the gear to the engagement position. A hammer drill mode in which the gear rotates integrally with the intermediate shaft to cause the tool holder to rotate and reciprocate the striking member,
The one eccentric pin is at a position allowing the retreat of the restricting member, the tool holder and the clutch, and the other eccentric pin advances the slide member to slide the gear to the non-engaging position. A hammer mode in which the gear is separated from the rotation of the intermediate shaft to cause only the reciprocating motion of the striking member;
The hammer drill is characterized in that the three operation modes can be selected.

Hammer drill according to claim 1, characterized in that rotation restricting means is provided for restricting the rotation of the gear in the disengaged position of the gear.

A small-diameter portion having a smaller diameter than the installation side of the conversion member is formed at the end of the intermediate shaft, the gear is externally mounted on the small-diameter portion, and provided at the base of the small-diameter portion at the engagement position. The hammer drill according to claim 1 or 2 , wherein the hammer drill engages with the engaging portion and integrally rotates with the intermediate shaft.

The motor is arranged below the intermediate shaft in the housing in a direction in which an axis of a rotation shaft intersects with the intermediate shaft, and a handle is provided at the rear of the tool holder. The hammer drill according to any one of Items 1 to 3 .