Manual drilling tool for corrugated building materials

Abstract

To provide a manual boring tool with which everyone can continuously perform boring work accurately and safely without requiring skill, in boring a through-hole in a top surface of a convex part of a corrugated plate-like building material.SOLUTION: A manual boring tool 1 is constituted of a handle member 4 formed in a cylindrical shape, a guide member 5, a retaining mechanism 10, a drill member 6 and a coil spring 7. The handle member 4 is formed of combined holding cylindrical bodies 8 coaxially connected to a tip of a handle main body 4a. The guide member 5, in which a corrugated jointed seat part 9 to a top surface of a convex part of a corrugated plate-like building material is provided at a tip part, is fitted and held in a coaxial state so that a tip side thereof protrudes by a predetermined length from tips of the holding cylindrical bodies 8 when a rear end side thereof is inserted into the holding cylindrical bodies 8, which can move and rotate in an axial direction with respect to the holding cylindrical bodies 8. The drill member 6, in which a cutting edge 6a is formed at a tip, is disposed coaxially with the handle member 4 and the guide member 5, moves integrally with the handle member 4 to bore a hole in the top surface of the convex part of the corrugated plate-like building material.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a manual drilling tool that enables anyone, without the need for skill, to perform drilling work accurately, safely and continuously in drilling through holes in the top surfaces of protruding parts of corrugated building materials. [Background technology]

[0002] As drilling tools used to drill through holes in the top surfaces of the convex parts of corrugated building materials, a manual drilling tool as shown in Patent Document 1 and electric drilling tools as shown in Patent Documents 2-6 have been proposed. The former manual drilling tool is lightweight, easy to handle, and convenient to use even in conditions where there is no power source.

[0003] Both the manual drilling tool and the electric drilling tool are constructed so that the rotating drill member is covered with a cylindrical guide member that acts as a cover to prevent accidental contact with the drill member, and the drill member and the guide member are in a relationship that allows them to move relatively along the axial direction of the drill member, and a coil spring urges the guide member to move elastically toward the tip of the drill member.

[0004] In addition, to prevent the drilling position of the drill bit from shifting when drilling, as in Patent Document 1, a manual drilling tool has a joint seat portion on the contact surface of the guide member with the corrugated building material, the joint seat portion being shaped to fit the top surface of the convex portion of the corrugated building material, and in the case of an electric drilling tool, as in Patent Documents 2 and 5, an elastic body is provided on the contact surface of the guide member with the corrugated building material, and when drilling with this joint seat portion or elastic body applied to the corrugated building material, the drill bit moves against the elastic force of the coil spring relative to the stopped guide member.

[0005] Incidentally, in the case of a structure in which the coil spring that elastically biases the guide member is exposed to the outside, as in Patent Documents 2 to 4, a skilled worker can use it without any problems. However, when used by general consumers for DIY purposes, there is a risk of injury from getting one's fingers caught in the coil spring, which may result in an accident other than contact with the drill member. For this reason, manual drilling tools that are often used by general consumers have a structure in which the coil spring is enclosed within the handle member, as in Patent Document 1.

[0006] The specific structure of a conventional manual drilling tool, as described in Patent Document 1, is such that a cylindrical guide member is inserted coaxially into the tip side of a handle member which is hollow and open at its tip so that it can move axially, and the drill member which fits between the handle member and the guide member has its rear end fixed to the rear end of the handle member and is set to a length such that its tip fits inside the guide member when the guide member is in the advanced position, and the tip of a coil spring which fits inside the handle member and fits around the drill member is abutted against the rear end of the guide member, giving the guide member elasticity to move towards the tip side, and the advanced position of the guide member is regulated by a pair of anti-slip mechanisms provided inside the handle member at the tip side position and at the rear end of the guide member.

[0007] With this type of manual drilling tool, when drilling, the handle member is gripped and the tip of the guide member is abutted against the corrugated building material, and the drill bit is advanced and rotated via the handle member relative to the fixed guide member to perform the drilling operation. Since the drill bit is advanced and rotated relative to the fixed guide member during drilling, it is necessary to secure a cylindrical space between the inner surface of the guide member and the outer surface of the drill bit to prevent them from rotating together. As both ends of this cylindrical space are open, the opening at the rear end communicates with the internal space in which the coil spring of the handle member is housed.

[0008] When drilling holes in corrugated building material using a manual drilling tool such as the one described above, cutting by the drill bit generates chips of the corrugated building material, which are stored by entering the cylindrical space. However, if the amount of chips increases as continuous drilling is performed, the chips in the cylindrical space will enter the internal space of the handle member that communicates with the cylindrical space, and as the chips accumulate in this internal space, they will become caught between the coil spring housed inside the handle member, causing problems with the expansion and contraction of the coil spring and hindering the drilling operation.

[0009] Here, in conventional manual drilling tools such as that of Patent Document 1, one possible means of preventing problems caused by chips getting caught in the coil spring is to increase the inner diameter of the guide member to widen the width of the cylindrical space and allow the chips to fall naturally from the tip opening of the guide member. However, such an increase in the inner diameter of the guide member is undesirable because it results in an increase in the diameter and weight of the entire manual drilling tool. In addition, even if the inner diameter of the guide member is increased, the relative axial movement of the drill member and guide member that occurs with each drilling operation causes chips in the chip discharge groove provided in the drill member and chips in contact with the inner surface of the guide member or the outer surface of the drill member to rise up and enter the internal space of the handle member, making it impossible to completely prevent chips from getting caught in the coil spring. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Design Registration No. 1271721 [Patent Document 2] JP 2011-224722 A [Patent Document 3] Japanese Utility Model Application Publication No. 3-107184 [Patent Document 4] Japanese Utility Model Application Publication No. 54-112677 [Patent Document 5] Japanese Utility Model Application Publication No. 52-17991 [Patent Document 6] Japanese Utility Model Application Publication No. 52-41085 Summary of the Invention [Problem to be solved by the invention]

[0011] Therefore, the object of this invention is to provide a manual drilling tool that, when drilling holes into the top surface of a convex portion of a corrugated building material, adequately protects the operator's body from the drill bit and the expandable coil spring, while preventing chips generated during drilling from entering and accumulating in the internal portion of the coil spring in the handle member, thereby allowing anyone, without the need for skill, to perform drilling work accurately, safely and continuously. [Means for solving the problem]

[0012] In order to solve the above problems, the present invention provides a manual drilling tool for drilling through holes in the top surfaces of the protruding parts of the corrugated building material, the manual drilling tool comprising a handle member formed in a hollow cylindrical shape with an open tip, a cylindrical guide member, a retaining mechanism, an awl member, and a coil spring, The guide member is cylindrical with both ends open, and has a seat at its tip to be attached to the top surface of the protruding portion of the corrugated building material. By inserting the guide member from the tip to the rear end into the handle member, the guide member is fitted and held coaxially with the handle member so that the tip side protrudes a predetermined length from the tip of the handle member, and the guide member can move axially and rotate about the axis relative to the handle member. the retaining mechanism is formed so that the inside of the tip side of the handle member and the rear end side of the guide member engage with each other with the tip side of the guide member protruding a predetermined length from the tip of the handle member, and hold the guide member in a retaining manner against the tip side of the handle member; the awl member has a cutting edge at its tip, is accommodated within the handle member and the guide member in a coaxial arrangement with the handle member and the guide member, is fixed to the handle member so as to move integrally with the handle member, and has an overall length such that when the relationship between the handle member and the guide member is in an extended state, the cutting edge at the tip is recessed into the guide member, and when the relationship between the handle member and the guide member is in a contracted state, the cutting edge side at the tip protrudes a predetermined length from the tip of the guide member; The coil spring is accommodated in a contracted state inside the handle member, and presses the rear end of the guide member to urge the guide member toward a forward position where a retaining mechanism engages with the guide member. A chip sealing member is interposed inside the handle member between the rear end face of the guide member and the end of the coil spring.

[0013] The handle member can be composed of a handle member main body formed into a hollow cylinder with an open tip, and a retaining cylinder that is coaxially connected to the tip of the handle member main body so as to form an extension thereof and is fitted onto the guide member, and the anti-slip mechanism can be configured to be connected by a step provided on the inner circumference of the retaining cylinder near the tip and a ridge provided on the outer periphery of the rear end of the guide member.

[0014] Furthermore, the guide member can be configured to be made of a transparent hard material.

[0015] In addition, the sealing member can be configured to be able to move axially and rotate inside the handle member, and to be formed as a ring-shaped disk with an inner diameter that is larger than the outer diameter of the guide member and the outer diameter of the coil spring and fits rotatably around the cone member.

[0016] The drill member is provided with a chip discharge groove that extends from the cutting edge at the tip to a position halfway in the axial direction toward the rear end, and the position of the sealing member relative to the chip discharge groove is set so that it is located closer to the rear end of the drill member than the rear end of the chip discharge groove.

[0017] The chip discharge groove may be configured so that its entire length is set within the guide member when the guide member is in an advanced position relative to the handle member where the anti-slip mechanism engages with the guide member. Effect of the Invention

[0018] According to the manual drilling tool of this invention, the awl member is contained within the handle member and guide member when not in use and is not exposed except when drilling holes, and the coil spring fitted around the awl member is contained within the handle member in a contracted state and is not exposed at all times. This prevents an inexperienced operator from accidentally touching the awl member or pinching his or her fingers in the coil spring which expands and contracts when drilling holes, which could result in injury. This advantage of the manual drilling tool is maintained, but a sealing member is interposed between the guide member and the coil spring, which prevents chips from entering and accumulating inside the handle member containing the coil spring when drilling holes continuously, thereby preventing malfunctions caused by chips impeding the expansion and contraction of the coil spring.

[0019] Furthermore, by forming the sealing member into a ring-shaped disk whose outer diameter is larger than the outer diameter of the guide member and the outer diameter of the coil spring and whose inner diameter fits rotatably around the drill member, and by interposing this between the rear end face of the guide member and the end of the coil spring, it is possible to block the communication between the cylindrical space of the guide member and the inside of the handle member, and to prevent fine chips from being rolled up and passing through the inside of the guide member and entering the part enclosed by the coil spring when drilling.

[0020] Furthermore, by interposing the sealing member between the rear end of the guide member and the end of the coil spring, the guide member and the coil spring are not in direct contact with each other, which also makes it possible to prevent the coil spring from getting caught in the anti-slip piece provided at the rear end of the guide member, preventing normal operation.

[0021] Furthermore, when drilling operations are continued continuously, most of the chips are discharged from the tip side of the guide member, but some of them accumulate in the chip discharge groove of the drill member and gradually accumulate and rise from the pointed tip of the drill member toward the handle portion. However, by setting the overall length of the chip discharge groove to a length that fits within the guide member when the guide member is in the advanced position relative to the handle member where the anti-slip mechanism engages, the fitting portion of the drill member with the sealing member always becomes a circular shaft-shaped portion, maintaining the sealing function, and the chip discharge groove does not communicate with the portion enclosed by the coil spring. Therefore, chips that have accumulated in the chip discharge groove can be prevented from entering the portion enclosed by the coil spring, further enhancing the effectiveness of the sealing member. [Brief description of the drawings]

[0022] [Figure 1] 1A is a front view showing a manual drilling tool according to an embodiment of the present invention, and FIG. [Diagram 2] FIG. 2 is a longitudinal sectional side view taken along the arrow aa in FIG. [Diagram 3] 1A is a plan view of a sealing member, and FIG. [Figure 4] FIG. 2 is a front view showing the cone member according to the embodiment of the present invention. [Diagram 5] FIG. 1 is a front view showing a coil spring according to an embodiment of the present invention. [Figure 6] FIG. 2A is a front view showing a guide member according to an embodiment of the present invention, and FIG. [Figure 7] 7 is a cross-sectional view of the guide member in FIG. 6 taken along the arrow cc. [Figure 8]FIG. 2 is a front view showing the retaining member according to the embodiment of the present invention. [Figure 9] 9 is a cross-sectional view of the retaining mechanism of FIG. 8 taken along the arrow dd. [Figure 10] FIG. 2 is a front view showing a handle member and an awl member fixed thereto according to an embodiment of the present invention. [Figure 11] 11 is a cross-sectional view of the handle member of FIG. 10 taken along the arrow ee. [Figure 12] FIG. 2(a) is a front view showing a state during drilling using the manual drilling tool of the present invention, and FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] As shown in Figures 1, 2 and 12, the manual drilling tool 1 of this invention is used to drill a through hole 3a in the top surface 3 of a convex portion of a corrugated building material 2, and is composed of a handle member 4, a cylindrical guide member 5, an drill member 6 and a coil spring 7.

[0024] The handle member 4 comprises a handle main body 4a formed in a hollow cylindrical shape with an open tip, and a holding cylinder 8 coaxially connected to the tip of the handle main body 4a so as to act as an extension of the handle main body 4a. The guide member 5 is cylindrical with both ends open, and has a corrugated joint seat 9 at its tip for connection to the convex top surface 3 of the corrugated building material 2. By inserting the rear end into the holding cylinder 8, the guide member 5 is fitted and held coaxially so that the tip side protrudes a predetermined length from the tip 12 of the holding cylinder 8, and is capable of moving axially and rotating relative to the holding cylinder 8.

[0025] The mating portion between the guide member 5 and the retaining cylindrical body 8 comprises a step portion 10a formed by a protrusion provided on the outer periphery of the rear end side of the guide member 5 and a step portion 10b provided on the inner periphery of the tip side of the retaining cylindrical body 8, and the guide member 5 engages with the retaining cylindrical body 8 with a predetermined length of the guide member 5 protruding from the tip of the retaining cylindrical body 8, thereby forming an anti-slip mechanism 10 that holds the guide member 5 in the forward position on the tip side in an anti-slip manner.

[0026] The awl member 6 has a cutting edge 6a at its tip, and is arranged coaxially with the handle member 4 and the guide member 5 throughout the interior of the handle member 4 and within the guide member 5. Its rear end is fixed to the handle body 4a so as to move integrally with the handle member 4. Its overall length is set so that the cutting edge 6a of the awl member 7 is recessed into the interior of the guide member 5 at a position close to the tip of the guide member 5 when the relationship between the handle member 4 and the guide member 5 is in an extended state as shown in Figure 2.

[0027] The coil spring 7 fits around the drill member 6 in a contracted state within the internal space 4b which is formed continuously from the inside of the handle body 4a of the handle member 4 to the inside of the retaining cylinder 8, with its tip pressed against the chip sealing member 11 interposed between it and the rear end face of the guide member 5, and presses the rear end of the guide member 5 forward in the axial direction via this sealing member 11, urging the guide member 5 to move elastically toward the forward position where the anti-slip mechanism 10 engages with the guide member 5.

[0028] As shown in Figures 2 and 3, the sealing member 11 is formed as a thin ring-shaped disk with an inner diameter that fits exactly around the parallel shaft portion of the drill member 6, allowing relative axial movement with the drill member 6, and an outer diameter that is approximately the same as the rear end face of the guide member 5. The sealing member 11 is constantly in pressure contact with the rear end face of the guide member 5 due to the pressure of the coil spring 7, and moves axially together with the guide member 5 while closing the opening at the rear end of the cylindrical space 5a formed between the inner periphery of the guide member 5 and the drill member 6, thereby blocking communication between the internal space 4b of the handle member 4 and the cylindrical space 5a of the guide member 5.

[0029] In this way, by closing the opening on the rear end side of the guide member 5 with the sealing member 11, it is possible to prevent chips generated inside the guide member 5 when drilling with the drill member 6 from entering the internal space 4b of the handle member 4, and it is possible to prevent the coil spring 7 contained in this internal space 4b from being hindered in its expansion and contraction due to the chips.

[0030] The parallel shaft portion of the drill member 6 is divided into a portion 6b used for drilling and a portion 6c onto which the coil spring 7 fits in an extended state. The diameter of the portion 6c onto which the coil spring 7 fits in an extended state is formed to be larger than the diameter of the portion 6b used for drilling, and the inner diameter 11a of the sealing member 11 and the diameter of the portion 6c onto which the coil spring 7 of the drill member 6 fits are set as nearly as possible to be the same.

[0031] More specifically, it is desirable that the inner diameter 11a of the sealing member 11 is set to be larger than the diameter of the portion 6c of the aperture member 6 on which the coil spring 7 is fitted, within a range of 1 mm or less in terms of the difference in diameter.

[0032] When drilling holes in a corrugated building material 2 using a manual drilling tool 1, the size of the chips will be larger than when drilling holes using an electric drilling tool because the rotation speed of the drill member 6 is slow. Therefore, if the gap between the diameter of the portion 6c where the coil spring 7 of the drill member 6 fits in an extended state and the inner diameter 11a of the sealing member 11 is up to about 1 mm, it is possible to sufficiently prevent the chips from passing through the gap between the sealing member 11 and the drill member 6 and entering the portion enclosed by the coil spring 7.

[0033] Furthermore, by making the sealing member 11 into a flat steel plate, it is possible to prevent it from rubbing against the guide member 5 and becoming worn, or from being pierced by the end of the coil spring 7, thereby suppressing the occurrence of malfunctions. Thus, when the sealing member 11 is made of steel, it is desirable to set its thickness to 1 mm or more so that it will not deform even if it comes into uneven contact with the guide member 5 during use and a concentrated force is applied to one part.

[0034] Incidentally, if the sealing member 11 is made of steel, this alone is sufficient to prevent deformation. However, to prevent chips from sticking to the surface of the sealing member 11 due to static electricity or oil adhesion, which would hinder the smooth discharge of the chips, it is preferable to take anti-fouling measures, such as by subjecting the surface to a chromate treatment.

[0035] The drill bit 6 is configured so that the cutting edge 6a at the tip of the drill bit 6 protrudes a predetermined length from the tip of the guide bit 5 when the relationship between the handle bit 4 and the guide bit 5 is in a contracted state, and the protruding length is desirably set in the range of 13 mm to 30 mm taking into consideration the shape of the corrugated building material 2, and the length of the tapered portion forming the cutting edge 6a at the tip of the drill bit 6 is set to 13 mm or less.

[0036] By setting the length of the cutting edge 6a of the drill bit 7 to 13 mm or less, even if the corrugated building material 2 has a small wave height and the base material 12 is made of steel that cannot be drilled, drilling into the top surface 3 of the convex portion of the corrugated building material 2 is completed before the tip of the cutting edge 6a comes into contact with the base material 12, and the tip of the drill bit 6 is not damaged.

[0037] Incidentally, if the length of the cutting edge 6a of the drill member 6 is set to 13 mm or more, when the corrugated building material 2 is attached to a base material 12 such as steel that cannot be drilled with the manual drilling tool 1, when drilling into the corrugated building material 2 with a small wave height, as the drill member 6 drills and advances from the top surface 3 of the convex portion toward the base material 12, the cutting edge 6a of the drill member 6 comes into contact with the base material 12, causing the drilling to be interrupted midway along the cutting edge 6a, and it is not possible to drill into the corrugated building material 2 until the cutting edge 6a is exceeded and the parallel shaft portion 6b of the drill member 6, which has the optimal drilling diameter, is reached.

[0038] In that case, it would not be possible to perform the drilling work by placing the corrugated building material 2 on the base 12 on which it was originally intended to be installed, and drilling holes in a position other than the base 12 would require specialized skills such as accurate marking, meaning that users who are not normally involved in construction, such as do-it-yourselfers, would not be able to drill holes in the correct position.

[0039] Furthermore, if the length of the drill member 6 is made to protrude beyond the tip of the guide member 5 by more than 30 mm, the overall length of the manual drilling tool 1 will be too long to handle manually, resulting in reduced workability, and the operating range of the guide member 5 will become too large, significantly increasing the frequency of malfunctions.

[0040] The drill member 6 is provided with a chip discharge groove 6d for discharging chips that have accumulated at the cutting edge 6a, which extends from the cutting edge 6a at the tip 13 to a position midway in the axial direction toward the rear end. The chip discharge groove 6d is set to a length such that its entire length fits within the guide member 5 when the guide member 5 is in the forward position relative to the handle member 4 where the anti-slip mechanism 10 engages with it.

[0041] By arranging the chip discharge groove 6d so as not to extend beyond the position of the sealing member 11 toward the rear end side, it is possible to prevent chips generated during drilling from passing through the chip discharge groove 6d, passing through the gap between the drill member 6 and the sealing member 11, and infiltrating into the side of the handle member 4 where the coil spring 7 is enclosed.

[0042] Next, the anti-slip mechanism 10 is formed by a step 10b provided on the inner circumference of the retaining cylindrical body 8 near the tip, and a protruding step 10a provided on the outer circumference of the rear end side of the guide member 5. If step 10b and step 10a are provided in a continuous, unbroken ring shape, even if the retaining cylindrical body 8 is molded from resin for the purpose of improving productivity, the effect can be fully maintained even if step 10b and step 10a become weakened and lose tension through wear.

[0043] The guide member 5 is formed using a transparent hard material, which may be a resin material such as ABS resin or polycarbonate resin. Preferably, polycarbonate resin is used, which makes it possible to obtain more suitable weather resistance and transparency.

[0044] Furthermore, when the above-mentioned resin is used as the material for the guide member 5, it is preferable to provide a peripheral wall thickness of 1.5 mm or more to provide sufficient strength; however, in the above-mentioned anti-slip mechanism 10, when combining the step portion 10b provided on the inner periphery tip side of the retaining cylinder 8 with the step portion 10a of the protrusion provided on the outer periphery of the rear end side of the guide member 5, the guide member 5 is too hard and a large force is required to combine them, which not only reduces the burden on the worker and reduces efficiency but also causes damage to the retaining cylinder 8 and the guide member 5. To avoid this problem, if a plurality of notches 13 are provided from the rear end side of the guide member 5 toward the tip 9, as shown in Figures 6 and 7, it becomes possible to efficiently perform the assembly work. [Explanation of symbols]

[0045] 1 Manual drilling tool 2. Corrugated building materials 3. Top surface of convex part 3a Through hole 4 Handle parts 4a Handle body 4b Interior space 5 Guide member 5a Cylindrical space 6 Cone member 6a cutting edge 6b Part used for drilling 6c Part that fits onto the coil spring 6d Chip discharge groove 7 Coil spring 8 Retaining member 9 Joint seat 10. Locking mechanism 10a Stepped section 10b Stepped section 11 Sealing member 11a Inner diameter 12 Base material 13 Cut

Claims

1. A manual drilling tool for drilling through holes in the top surface of a protruding portion of a corrugated building material, the tool comprising a handle member formed in a hollow cylindrical shape with an open tip, a cylindrical guide member, a retaining mechanism, an awl member, and a coil spring; The guide member is cylindrical with both ends open, and has a seat at its tip for connection to the top surface of the protruding portion of the corrugated building material. By inserting the rear end into the handle member, the guide member is fitted and held coaxially with the handle member so that the tip protrudes a predetermined length from the tip of the handle member, and the guide member can move axially and rotate about the axis relative to the handle member. the retaining mechanism is formed so that the inside of the tip end side of the handle member and the rear end side of the guide member are engaged with each other in a state in which the tip end side of the guide member protrudes a predetermined length from the tip of the handle member, and the guide member is held in a retaining state relative to the tip end side of the handle member; the awl member has a cutting edge at its tip, is fitted coaxially with the handle member and the guide member throughout the handle member and within the guide member, and is fixed to the handle member so as to move integrally with the handle member, and has an overall length such that when the relationship between the handle member and the guide member is in an extended state, the cutting edge at the tip is recessed into the guide member, and when the relationship between the handle member and the guide member is in a contracted state, the cutting edge side at the tip protrudes a predetermined distance from the tip of the guide member; The coil spring is accommodated in a contracted state inside the handle member, and presses the rear end of the guide member, thereby urging the guide member to move elastically toward a forward position where the retaining mechanism engages with the guide member. In a manual drilling tool, A manual drilling tool, characterized in that a sealing member for sealing chips is interposed inside the handle member between a rear end surface of the guide member and an end of the coil spring.

2. 2. The manual drilling tool according to claim 1, characterized in that the handle member is composed of a handle body formed in a hollow cylindrical shape with an open tip, and a retaining cylinder that is coaxially connected to the tip of the handle body so as to extend therefrom and is fitted onto the guide member, and the anti-slip mechanism is formed by a step portion provided on the inner circumference of the retaining cylinder near the tip, and a protrusion provided on the outer periphery of the rear end of the guide member.

3. 3. The manual drilling tool according to claim 1, wherein the guide member is made of a transparent hard material.

4. The manual drilling tool according to any one of claims 1 to 3, characterized in that the sealing member is accommodated inside the handle member so as to be able to move axially and rotate, and is formed as a ring-shaped disk having an inner diameter larger than the outer diameter of the guide member and the outer diameter of the coil spring and fitting rotatably around the drill member.

5. 5. The manual drilling tool according to claim 1, wherein the drill member has a chip discharge groove extending from the cutting edge at the tip to a position midway in the axial direction toward the rear end, and the position of the sealing member relative to the chip discharge groove of the drill member is set so as to be located closer to the rear end of the drill member than the rear end of the chip discharge groove.

6. The manual drilling tool according to claim 5, characterized in that the chip discharge groove provided in the drill member is set to a length such that its entire length fits within the guide member when the guide member is in an advanced position relative to the handle member where the anti-slip mechanism engages with the guide member.

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