JP5295174B2

JP5295174B2 - Spare blade saw

Info

Publication number: JP5295174B2
Application number: JP2010119090A
Authority: JP
Inventors: 道介友定
Original assignee: レザーソー工業株式会社
Priority date: 2010-05-25
Filing date: 2010-05-25
Publication date: 2013-09-18
Anticipated expiration: 2030-05-25
Also published as: JP2011245672A

Abstract

<P>PROBLEM TO BE SOLVED: To provide a blade replaceable saw improved in sharpness and durability. <P>SOLUTION: An upper side of a saw blade plate 1 is inserted in a cross-sectionally inverted U-shaped back metal 2, and the base of the plate 1 is inserted in a helve 3. Notches 4 and 5 are provided in the back metal 2 and the edge of shank of the saw blade plate 1, and by shallowing the notch 4 of the plate 1, the plate 1 is pushed up with the top of a screw 6 threaded from under the helve 3 so that the plate 1 is brought into close contact with the inner upper edge of the back metal 2. A linear contacting section 7 brought into close contact with the back metal 2 is formed in the base end of the plate 1, and a noncontact section 9 positioned below the inner upper edge of the back metal 2, with the front end of the contact section 7 as supporting point 8, is formed ahead of the supporting point 8. Vibration generated in cutting work is absorbed by a spring effect of the plate 1 itself, and does not affect the whole of the plate. <P>COPYRIGHT: (C)2012,JPO&INPIT

Description

この発明は、断面倒Ｕ字状の背金と、背金に挿入する鋸刃板と、背金及び鋸刃板の基部である中子部分を挿入保持する把持柄とで構成する替刃鋸に関する発明である。 The present invention relates to a replaceable blade saw composed of a back metal having an inverted U-shaped cross section, a saw blade plate to be inserted into the back metal, and a grip handle for inserting and holding the core part which is the base of the back metal and the saw blade plate. It is invention regarding.

替刃鋸には、断面倒Ｕ字状の背金と、背金に挿入する鋸刃板と、背金及び鋸刃板の基部である中子部分を挿入保持する把持柄とで構成し、把持柄に挿入する背金及び鋸刃板の基部である中子部分の下縁にそれぞれ切欠部を設け、切欠部の深さを、背金の切欠部よりも鋸刃板の切欠部を浅く形成し、把持柄の下方から螺入させたねじの先端で鋸刃板を押し上げ、鋸刃板の上縁を背金の内面上縁に密接させて鋸刃板を安定させる替刃鋸が知られている。 The replaceable blade saw is composed of a back metal having a U-shaped cross section, a saw blade plate to be inserted into the back metal, and a grip handle for inserting and holding the core part which is the base of the back metal and the saw blade plate, A notch is provided at the lower edge of the core that is the base of the back metal and the saw blade plate to be inserted into the gripping handle, and the depth of the notch is shallower than the notch of the back metal. A replaceable blade saw that stabilizes the saw blade plate by pushing up the saw blade plate with the tip of the screw formed and screwed from below the gripping handle, bringing the upper edge of the saw blade plate into close contact with the upper edge of the inner surface of the back metal It has been.

実公昭４７−１５７４９号公報Japanese Utility Model Publication No. 47-15749 実開昭５５−１５１５０１号公報Japanese Utility Model Publication No. 55-151501 特開２００５−２８００４０号公報JP 2005-280040 A 特開２００７−３３１１３１号公報JP 2007-331131 A

特許文献１及び２に記載された発明は、背金の全長にわたって鋸刃板の上縁が密接して保持される。このとき、特許文献１及び２の実施形態では、背金が鋸刃板の先端にまで達していない。特許文献３に記載された発明は、背金の代わりに把持柄内に倒Ｖ字状の支受金具を配置し、支受金具の範囲において鋸刃板を支持している。このような従来技術は、鋸刃板の剛性によって強度を維持しているため、鋸刃板の厚みはある程度厚いものが利用されている。 In the inventions described in Patent Documents 1 and 2, the upper edge of the saw blade plate is held in close contact over the entire length of the back metal. At this time, in the embodiments of Patent Documents 1 and 2, the back metal does not reach the tip of the saw blade plate. In the invention described in Patent Document 3, an inverted V-shaped support fitting is arranged in the grip handle instead of the back metal, and the saw blade plate is supported in the range of the support fitting. In such a conventional technique, since the strength is maintained by the rigidity of the saw blade plate, the saw blade plate having a certain thickness is used.

特許文献４に記載された発明では、背金が鋸刃板の前端にまで延長されているため、強度が向上し薄くて切れ味の鋭い鋸刃板を採用することができる。しかしながら、引用文献４に記載された替刃鋸では、鋸刃板の上縁が背金の全長にわたって密接する構造であるため、切断作業によって鋸歯に発生した振動が背金を介して鋸刃板全体に伝わり、切断精度や切れ味に悪影響を及ぼし、ひいては鋸刃板や鋸歯を損傷させる可能性があることが判明した。 In the invention described in Patent Document 4, since the back metal is extended to the front end of the saw blade plate, it is possible to adopt a saw blade plate that has improved strength and is thin and sharp. However, in the replaceable blade saw described in the cited document 4, since the upper edge of the saw blade plate is in close contact over the entire length of the back metal, the vibration generated in the saw teeth by the cutting operation is caused through the back metal to the saw blade plate. It has been found that it has a negative effect on cutting accuracy and sharpness, and may damage the saw blade and the saw blade.

上記、従来技術の欠点に鑑み、本発明は鋸刃板下縁の鋸歯に発生する振動の伝播を抑制して切れ味を向上させるとともに、振動による鋸刃板の損傷を防止して耐久性を向上させる替刃鋸を実現することを目的とするものである。さらに、本発明の他の目的は、より薄い鋸刃板の採用を可能とし、精度の高い切断が可能な替刃鋸を実現することである。 In view of the above-mentioned drawbacks of the prior art, the present invention improves the sharpness by suppressing the propagation of vibration generated in the saw blade at the lower edge of the saw blade plate, and improves the durability by preventing damage to the saw blade plate due to vibration. The purpose is to realize a replaceable blade saw. Furthermore, another object of the present invention is to realize a replaceable blade saw capable of using a thinner saw blade plate and capable of cutting with high accuracy.

本発明に係る替刃鋸は、断面倒Ｕ字状の背金２に鋸刃板１の上辺部分を挿入し、背金２及び鋸刃板１の基部であって把持柄３に挿入する中子部分1a、2aの下縁にそれぞれ切欠部を設け、切欠部の深さを背金２の切欠部５よりも鋸刃板１の切欠部４を浅く形成し、把持柄３の下方から螺入させたねじ６の先端で鋸刃板１の切欠部４を押し上げ、鋸刃板１の上縁を背金２の内面上縁に密接させる替刃鋸に関するものである。 In the replaceable blade saw according to the present invention, the upper side portion of the saw blade plate 1 is inserted into the back metal 2 having a U-shaped cross section and inserted into the grip handle 3 at the base of the back metal 2 and the saw blade plate 1. A notch is provided at the lower edge of each of the child parts 1a and 2a, and the notch is formed so that the notch 4 is shallower than the notch 5 of the back metal 2 and the saw blade plate 1 is shallower than the grip handle 3. The present invention relates to a replaceable blade saw that pushes up the notch portion 4 of the saw blade plate 1 with the tip of the screw 6 inserted so that the upper edge of the saw blade plate 1 is in close contact with the upper edge of the inner surface of the back metal 2.

前記目的を達成する請求項１記載の発明は、背金２の内面上縁を全長にわたって直線状に形成する。一方、鋸刃板１には、上縁基部であって基端から切欠部４よりも先方位置に達し、背金２に密接する直線状の接触部分７を形成するとともに、接触部分７の前端を支点部８とし、支点部８よりも先方の鋸刃板１上縁を背金２の内面上縁よりも下方に位置させて非接触部分９とする。 In the invention according to claim 1, which achieves the object, the upper edge of the inner surface of the back metal 2 is formed linearly over the entire length. On the other hand, the saw blade plate 1 is formed with a linear contact portion 7 which is an upper edge base portion and reaches a position ahead of the notch portion 4 from the base end and is in close contact with the back metal 2, and the front end of the contact portion 7. Is the fulcrum part 8, and the upper edge of the saw blade plate 1 ahead of the fulcrum part 8 is positioned below the upper edge of the inner surface of the back metal 2 to form a non-contact part 9.

請求項２記載の発明は、接触部分７の直線方向に対して支点部８よりも先方の上縁を下方に傾斜する直線状に形成することによって鋸刃板１上縁の非接触部分９を形成することである。
請求項３記載の発明は、鋸刃板１上縁の支点部８に段部10を形成し、この段部10より先方を接触部分７よりも下方に位置し、接触部分７の直線方向と平行に非接触部分９を形成することである。 According to the second aspect of the present invention, the non-contact portion 9 on the upper edge of the saw blade plate 1 is formed by forming the upper edge ahead of the fulcrum portion 8 in a straight line shape inclined downward with respect to the linear direction of the contact portion 7. Is to form.
According to the third aspect of the present invention, a step portion 10 is formed at the fulcrum portion 8 at the upper edge of the saw blade plate 1, and the tip of the step portion 10 is positioned below the contact portion 7, and the linear direction of the contact portion 7 is The non-contact part 9 is formed in parallel.

請求項４記載の発明は、断面倒Ｕ字状に形成する背金２の左右両側壁間の隙間Ｘを、鋸刃板１の厚みＴと一致させ、鋸刃板１の面方向の振れを防止するとともに、背金２によって鋸刃板１に面方向の挟持力が作用しないようにすること、請求項５記載の発明は、背金２の先端を、鋸刃板１の前端よりも前方に突出させることである。 In the invention according to claim 4, the gap X between the left and right side walls of the back metal 2 formed in a U-shaped cross section is made to coincide with the thickness T of the saw blade plate 1, so that the vibration in the surface direction of the saw blade plate 1 is made. And preventing the clamping force in the surface direction from acting on the saw blade plate 1 by the back metal 2. The invention according to claim 5 is configured such that the tip of the back metal 2 is in front of the front end of the saw blade plate 1. To project.

請求項１記載の発明によれば、鋸刃板１の上縁は、直線状の接触部分７が背金２の内面上縁に密着して安定する。木材などの切断作業によって鋸歯11に力が作用した場合、すなわち、鋸刃板１の下縁に振動や衝撃が発生し、あるいは鋸刃板１を上方に押し上げる力が作用した場合、鋸刃板１の非接触部分９が上方に撓む、すなわち鋸刃板１の弾性（スプリング効果）によって上方への振動や衝撃を吸収し、鋸刃板１全体を安定させ、切れ味を向上させる効果がある。また、振動を吸収する結果、個々の鋸歯に対する負担が軽減し、耐久性を向上させる。
鋸刃板１の上縁全体が背金に密接している場合は、鋸歯11に発生した振動が鋸刃板１全体に伝播し、鋸歯11全体が振動し円滑な切断作用を阻害する可能性がある。 According to the first aspect of the present invention, the upper edge of the saw blade plate 1 is stabilized by the linear contact portion 7 being in close contact with the upper edge of the inner surface of the back metal 2. When a force is applied to the saw blade 11 by cutting work such as wood, that is, when vibration or impact is generated on the lower edge of the saw blade plate 1 or a force pushing the saw blade plate 1 upward is applied, the saw blade plate 1 non-contact portion 9 bends upward, that is, it has the effect of absorbing upward vibration and impact by the elasticity (spring effect) of the saw blade plate 1, stabilizing the entire saw blade plate 1 and improving the sharpness. . Further, as a result of absorbing the vibration, the burden on the individual saw teeth is reduced and the durability is improved.
When the entire upper edge of the saw blade plate 1 is in close contact with the back metal, the vibration generated in the saw blade 11 may propagate to the entire saw blade plate 1 and the entire saw blade 11 may vibrate and hinder smooth cutting action. There is.

請求項２記載の発明は、非接触部分９を形成する一実施例であるが、鋸刃板１の上縁全体をへ字状に形成することになり、支点部８を支点として先方全体が安定的に上方に撓む状態を実現することができる。請求項３記載の発明は、非接触部分９を形成する他の実施例であるが、非接触部分９全体の確実な非接触状態を実現し、段部10形成部分において撓みを助長し、衝撃や振動を吸収する効果がある。 The invention according to claim 2 is an embodiment for forming the non-contact portion 9, but the entire upper edge of the saw blade plate 1 is formed in a hemispherical shape, and the entire tip is formed with the fulcrum portion 8 as a fulcrum. It is possible to realize a state of bending upward stably. The invention according to claim 3 is another embodiment for forming the non-contact portion 9, but realizes a reliable non-contact state of the entire non-contact portion 9, promotes bending at the step 10 forming portion, And has the effect of absorbing vibration.

請求項４記載の発明によれば、鋸刃板１が上方に撓む際、鋸刃板１を挟持することによって鋸刃板１に無理な力が作用しない。したがって、従来の替刃鋸に比較して非常に薄い鋸刃板を使用し、精度の高い切断をすることができる。
請求項５記載の発明によれば、鋸刃板１の全長にわたって上辺部分を保持するため、鋸刃板１を確実に保持することができる。 According to the fourth aspect of the present invention, when the saw blade plate 1 bends upward, an unreasonable force does not act on the saw blade plate 1 by sandwiching the saw blade plate 1. Therefore, a very thin saw blade plate can be used as compared with a conventional replaceable saw and cutting can be performed with high accuracy.
According to the fifth aspect of the present invention, since the upper side portion is held over the entire length of the saw blade plate 1, the saw blade plate 1 can be reliably held.

図１は、一部を切断拡大表示した、本発明替刃鋸の正面図、FIG. 1 is a front view of the replaceable blade saw of the present invention, partially enlarged and displayed. 図２は、鋸刃板と背金を分離させた状態を示す替刃鋸の正面図、FIG. 2 is a front view of a replaceable blade saw showing a state where the saw blade plate and the back metal are separated, 図３は、一部省略の替刃鋸の縦断面図、FIG. 3 is a longitudinal sectional view of a partly omitted replaceable blade saw, 図４は、図３のIV−IV線拡大断面図、4 is an enlarged sectional view taken along line IV-IV in FIG. 図５は、図３のV−V線拡大断面図、FIG. 5 is an enlarged cross-sectional view taken along line VV in FIG. 図６は、鋸刃板の別の実施形態を示す正面図ある。FIG. 6 is a front view showing another embodiment of the saw blade plate.

以下、本発明に係る替刃鋸の実施形態を添付の図面に基づいて説明する。
図１は、本発明替刃鋸の正面図であって、一部を切断拡大表示している。本発明に係る替刃鋸は、断面倒Ｕ字状の背金２に鋸刃板１の上辺部分を挿入し、背金２に鋸刃板１の上辺部分を挿入した状態で、中子部分1a、2aを把持柄３の挿入孔12に挿入している。 DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a replaceable blade saw according to the present invention will be described with reference to the accompanying drawings.
FIG. 1 is a front view of the replaceable blade saw of the present invention, and a part of the blade is enlarged and displayed. The replaceable blade saw according to the present invention has a core portion in a state where the upper side portion of the saw blade plate 1 is inserted into the back metal 2 having a U-shaped cross section and the upper side portion of the saw blade plate 1 is inserted into the back metal 2. 1a and 2a are inserted into the insertion holes 12 of the grip handle 3.

背金２及び鋸刃板１を把持柄３に固定するには、鋸刃板１の基部である中子部分1aを背金２の基部である中子部分2aにぴったりと挿入できる幅に形成し、一体的に挿入した中子部分を把持柄３の挿入孔12に挿入する。このとき、把持柄３の挿入孔12に挿入する鋸刃板１及び背金２の中子部分には、下縁の重なり合う位置に同じ幅の切欠部４、５を設けている。そして、鋸刃板１の切欠部４は、背金５の切欠部５よりも浅く形成し、把持柄３の下方から螺入させたねじ６の先端で切欠部４において鋸刃板１を押し上げることによって、鋸刃板１の上縁を背金２の内面上縁に密接させるとともに把持柄３の定位置に固定できるようにしている。 In order to fix the back metal 2 and the saw blade plate 1 to the gripping handle 3, the core portion 1a which is the base portion of the saw blade plate 1 is formed with a width that can be inserted into the core portion 2a which is the base portion of the back metal 2 exactly. Then, the core part inserted integrally is inserted into the insertion hole 12 of the grip handle 3. At this time, in the core portion of the saw blade plate 1 and the back metal 2 to be inserted into the insertion hole 12 of the gripping handle 3, cutout portions 4 and 5 having the same width are provided at positions where the lower edges overlap. The notch portion 4 of the saw blade plate 1 is formed shallower than the notch portion 5 of the back metal 5, and the saw blade plate 1 is pushed up at the notch portion 4 by the tip of the screw 6 screwed from below the gripping handle 3. Thus, the upper edge of the saw blade plate 1 is brought into close contact with the upper edge of the inner surface of the back metal 2 and can be fixed to a fixed position of the gripping handle 3.

図中13は、把持柄３の挿入孔12に固定した雌ねじ部材であり、ねじ６を雌ねじ部材12に螺合させてねじ６の先端で鋸刃板１を上方に押し上げるとともに、切欠部４、５の幅をねじ６の直径と一致させることによって、鋸刃板１と背金２の長手方向の移動を阻止している。 In the figure, reference numeral 13 denotes a female screw member fixed to the insertion hole 12 of the gripping handle 3. The screw 6 is screwed into the female screw member 12 to push the saw blade plate 1 upward at the tip of the screw 6. By making the width of 5 coincide with the diameter of the screw 6, the longitudinal movement of the saw blade 1 and the back metal 2 is prevented.

図２に示すように、背金２の上辺は、全長に渡って直線的に形成する。すなわち、所定の形状に形成した板材を二つ折りとして形成する。
一方、薄い鋼板で形成する鋸刃板１の上辺は、ほぼ中子部分、具体的には把持柄３の先端よりも少し先方位置を支点部８とし、支点部８よりも基方を直線的な接触部分７とし、支点部８よりも先方の上辺をやや下向きの直線に形成して非接触部分８としている。 As shown in FIG. 2, the upper side of the back metal 2 is formed linearly over the entire length. That is, the plate material formed in a predetermined shape is formed in half.
On the other hand, the upper side of the saw blade plate 1 formed of a thin steel plate has a fulcrum portion 8 at a position slightly ahead of the core portion, specifically the tip of the gripping handle 3, and the base is straighter than the fulcrum portion 8. The contact portion 7 is formed as a non-contact portion 8 by forming the upper side ahead of the fulcrum portion 8 as a straight line slightly downward.

上記構成とすることによって、中子部分を把持柄３の挿入孔12に挿入し、ねじ６を締め上げた場合に、ねじ６によって切欠部４を押し上げられた鋸刃板１は、直線的な接触部分７が背金２の内面上縁に押圧されて密接する。
一方、支点部８よりも先方の鋸刃板１の上縁は、背金２の内面上縁に接触しない非接触部分９となる。非接触部９は先方へ行くにしたがって大きな隙間Ｚとなる。隙間Ｚは、最小で２mm程度とするのが効果的であった。 With the above configuration, when the core portion is inserted into the insertion hole 12 of the gripping handle 3 and the screw 6 is tightened, the saw blade plate 1 whose notch 4 is pushed up by the screw 6 is linear. The contact portion 7 is pressed against and closely contacts the upper edge of the inner surface of the back metal 2.
On the other hand, the upper edge of the saw blade plate 1 ahead of the fulcrum portion 8 becomes a non-contact portion 9 that does not contact the upper edge of the inner surface of the back metal 2. The non-contact portion 9 becomes a large gap Z as it goes further. It was effective to set the gap Z to a minimum of about 2 mm.

図３に示す替刃鋸で切断作業を行うと、切断作業にともなって鋸歯部分に発生した振動、衝撃は鋸刃板１の弾性、すなわち撓みによって吸収され鋸刃板１全体に伝播しない。切断作業に際して、木目の偏り、節の存在などによって一部の鋸歯に衝撃や振動が発生する場合があるが、本発明では発生した振動が鋸刃板１全体に伝播せず、振動が発生した部分以外の鋸歯は、振動や衝撃の影響を受けることなく切断作業を行うことができる。すなわち、切断材料に部分的な硬さの変化がある場合であっても、切れ味に変化がなく、円滑に切断することができることになる。 When the cutting operation is performed with the replaceable blade saw shown in FIG. 3, the vibration and impact generated in the sawtooth portion due to the cutting operation are absorbed by the elasticity of the saw blade plate 1, that is, bent, and do not propagate to the entire saw blade plate 1. In the cutting operation, impact and vibration may occur in some of the saw blades due to the deviation of the grain, the presence of nodes, etc., but in the present invention, the generated vibration does not propagate to the entire saw blade plate 1 and vibration is generated. The saw blades other than the portion can be cut without being affected by vibration or impact. That is, even when there is a partial change in hardness in the cutting material, there is no change in sharpness and cutting can be performed smoothly.

非接触部分９は、図２に示す実施形態のように鋸刃板１の上縁を全体としてへ字状に形成するほか、図６に示すように支点部８に段部10を形成し、段部10より先方を接触部７と平行に形成することもできる。この実施形態では、非接触部分は、その全長において背金２内面上縁との間に一定の隙間Ｚが形成されることになる。 As shown in FIG. 2, the non-contact portion 9 is formed in the upper edge of the saw blade plate 1 as a whole in a U-shape, as shown in FIG. 6, and a step portion 10 is formed on the fulcrum portion 8 as shown in FIG. The part ahead of the step part 10 can also be formed in parallel with the contact part 7. In this embodiment, a constant gap Z is formed between the non-contact portion and the upper edge of the inner surface of the back metal 2 over its entire length.

鋸刃板１の上辺部分は、倒Ｕ字状に折曲した背金２に支持されるが、背金２の左右両側壁間の隙間Ｘは、鋸刃板１の厚みＴとできるだけ一致させるのが好ましい。この、隙間Ｘを鋸刃板１の厚みＴと一致させる精度は、鋸刃板１の面方向の振れを防止することができるとともに、背金２によって鋸刃板１に面方向の挟持力が作用しない範囲である。
また、背金２は図３に示すように、鋸刃板１よりも長く形成し、鋸刃板１の全長を背金２で支持することができるようにするのが好ましい。これにより、非常に薄い鋸刃板１を使用する場合であっても、十分な強度を得ることができる。 The upper side portion of the saw blade plate 1 is supported by a back metal 2 bent in an inverted U shape, and the gap X between the left and right side walls of the back metal 2 is made to match the thickness T of the saw blade plate 1 as much as possible. Is preferred. The accuracy with which the gap X matches the thickness T of the saw blade plate 1 can prevent the saw blade plate 1 from being shaken in the surface direction, and the back blade 2 provides a clamping force in the surface direction to the saw blade plate 1. It is the range that does not work.
Further, as shown in FIG. 3, the back metal 2 is preferably formed longer than the saw blade plate 1 so that the entire length of the saw blade plate 1 can be supported by the back metal 2. Thereby, even if it is a case where the very thin saw blade board 1 is used, sufficient intensity | strength can be obtained.

本発明者らは、鋸刃板の厚みを、例えば0.15mm程度の非常に薄い板材を採用し、振動を鋸刃板のスプリング効果で吸収し、精度の高い切断を行うことができる替刃鋸を実現した。
鋸刃板１の上縁全体が背金２に密接している従来の替刃鋸では、背金２と鋸刃板１が相対的に移動することがないため、鋸刃板１が背金２にしっかりと挟持されるものであっても、鋸刃板１に応力が発生しない。ところが、本発明では鋸刃板１の上縁と背金の内面上縁との間に隙間が形成され、背金２と鋸刃板１が相対的に上下方向に移動する。そのため、鋸刃板１が背金２に挟持された状態であると、鋸刃板１と背金２の相対的な移動にともなって応力が発生し、鋸刃板１の板厚が薄いものであると変形や歪となってしまう。したがって、背金２の左右両側壁間の隙間Ｘは、鋸刃板１の厚みＴよりもプラス側の誤差であって、誤差は可能な限り小さいことが望ましい。 The present inventors adopt a very thin plate material having a saw blade plate thickness of, for example, about 0.15 mm, absorb the vibration by the spring effect of the saw blade plate, and can perform highly accurate cutting. Realized.
In the conventional spare blade saw in which the entire upper edge of the saw blade plate 1 is in close contact with the back metal 2, the back metal 2 and the saw blade plate 1 do not move relative to each other. No stress is generated on the saw blade plate 1 even if it is firmly held between the two. However, in the present invention, a gap is formed between the upper edge of the saw blade plate 1 and the inner edge of the inner surface of the back metal, and the back metal 2 and the saw blade plate 1 move relatively in the vertical direction. Therefore, when the saw blade plate 1 is sandwiched between the back metal 2, stress is generated with the relative movement of the saw blade plate 1 and the back metal 2, and the thickness of the saw blade plate 1 is thin. If it is, it will become a deformation | transformation and distortion. Therefore, the gap X between the left and right side walls of the back metal 2 is an error on the plus side of the thickness T of the saw blade plate 1 and is desirably as small as possible.

１…鋸刃板、 1a、2a…中子部分、２…背金、３…把持柄、４、５…切欠部、６…ねじ、７…接触部分、８…支点部、９…非接触部分、 10…段部、 11…鋸歯、 12…挿入孔、 13…雌ねじ部材。 DESCRIPTION OF SYMBOLS 1 ... Saw blade board, 1a, 2a ... Core part, 2 ... Back metal, 3 ... Grip handle, 4, 5 ... Notch part, 6 ... Screw, 7 ... Contact part, 8 ... Supporting part, 9 ... Non-contact part , 10 ... Stepped part, 11 ... Saw tooth, 12 ... Insertion hole, 13 ... Female thread member.

Claims

Insert the upper side portion of the saw blade plate into a U-shaped back metal with a cross-section, and provide notches on the lower edge of the core portion which is the base of the back metal and the saw blade plate and is inserted into the gripping handle. The depth of the part is formed shallower than the notch of the back metal, and the notch of the saw blade is pushed up by the tip of the screw threaded from below the gripping handle. In a replaceable blade saw that brings the upper edge into close contact with the inner upper edge of the back metal,
While forming the upper edge of the inner surface of the back metal in a straight line over the entire length, reaching the position ahead of the notch at the upper edge base of the saw blade plate, and forming a linear contact portion in close contact with the back metal, A replaceable blade saw characterized in that the front end of the contact portion is a fulcrum portion, and the upper edge of the saw blade plate ahead of the fulcrum portion is positioned below the upper edge of the inner surface of the back metal to be a non-contact portion.

2. The replaceable blade saw according to claim 1, wherein the non-contact portion of the upper edge of the saw blade plate is formed in a linear shape in which the upper edge ahead of the fulcrum portion is inclined downward with respect to the linear direction of the contact portion. .

The upper edge of the saw blade plate is formed with a step portion at a fulcrum portion, the tip portion of the saw blade portion is positioned below the contact portion, and a non-contact portion parallel to the linear direction of the contact portion is formed. The replaceable blade saw according to Item 1.

The gap between the left and right side walls of the back metal formed in an inverted U-shaped cross section is matched with the thickness of the saw blade plate to prevent the saw blade plate from swinging in the surface direction. The replaceable blade saw according to any one of claims 1 to 3, wherein the clamping force is not applied.

The replaceable blade saw according to any one of claims 1 to 4, wherein the tip of the back metal protrudes forward from the front end of the saw blade plate.