JPH0616710U - Screw with drill for pilot hole - Google Patents

Abstract

(57) [Abstract] [Purpose] A screw having a pilot hole drill that can smoothly perform pilot hole drilling and screwing operation at the same time without being disturbed by chips or the like generated when drilling a pilot hole. To provide. [Structure] A chip escape groove is formed in a spiral shape from the front end to the rear end of a cylindrical main body of a screw having a drill portion, and the front drill cutting blade of the drill portion is used for rear drill cutting of the main body portion. Smaller than the blade. [Effect] The pilot hole can be opened and the screwing operation can be performed at the same time, the chips discharged from the drill can be removed reliably, there is no obstruction to the screwing operation by the chips, and the screw after screwing loosens,
There is no dropout.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a screw having a pilot hole drill capable of performing a screwing operation while drilling a screw pilot hole.

[0002]

[Prior art]

 Conventionally used screws such as screws have a screw part with a spiral groove formed on the outer peripheral surface, and by rotating the head of this screw part with a screwdriver or the like, the screw or the like can be attached to an object such as a wall or plate. It is designed to be screwed in.

[0003]

[Problems to be solved by the device]

 When performing a screwing operation using such a screw, since the screwing operation is performed after the pilot hole is drilled in the object in advance using a drill or the like, the drilling operation and the screwing operation are performed separately. It has to be done using tools, which makes the work cumbersome. In addition, if the pilot hole is not drilled correctly, there is a possibility that a screwing failure may occur, the screw may loosen even if it is screwed in, or in some cases, the screw hole may come off the screw hole. In recent years, there is also one in which a drill part is integrally formed at the tip of the screw part and the screw can be rotated while the pilot hole of the screw is drilled while the screw is rotated. . However, in such a screw, the chips generated when the screw hole is drilled by the drill portion interferes with the rotation or insertion of the screw, and there is a drawback that a smooth screw operation cannot be performed. there were.

The present invention has been made in order to solve the problems of the above-described prior art, and is capable of smoothly forming a pilot hole without being disturbed by chips or the like generated when the pilot screw hole is drilled. An object of the present invention is to provide a screw having a pilot hole drill capable of simultaneously performing the loading operation.

[0005]

Means for Solving the Problems The present invention for achieving the above object includes a screw portion having a spiral groove formed on an outer peripheral surface thereof, and a head for rotation provided at a rear end of the screw portion. In the screw having, the screw part starts from the cylindrical main body part, the drill part for the pilot hole provided at the tip of the main body part and having the drill point and the cutting edge, and the drill point. It has a chip escape groove formed in a spiral shape up to the rear end of the main body, and a front drill cutting blade and a rear drill cutting blade are formed on the drill portion and the main body, respectively. It is a screw having a pilot hole drill. A concave groove may be formed at a position where a surface orthogonal to the central axis of the main body of the screw portion intersects the outer peripheral surface, and a packing ring may be fitted in the concave groove. In this case, the inner diameter of the groove is smaller than the inner diameter of the circle formed at the bottom of the chip escape groove, and the outer diameter of the packing ring fitted in the groove is slightly larger than the outer diameter of the main body. It is preferable to increase it.

[0006]

[Action]

 In this invention, when the head is rotated by using a screwdriver or a spanner, first, the front drill cutting blade of the drill portion for the pilot hole drills the pilot hole in the object. The chips generated at this time are discharged through the chip relief groove formed in the drill part. Further, when the head is rotated, the rear drill cutting blade formed on the main body expands the diameter of the prepared hole formed by the drill portion. The chips generated at this time are also discharged through the chip relief grooves formed in the main body. Therefore, the chips do not enter between the screw portion and the pilot hole during drilling of the pilot hole by the drill part and during drilling of the large pilot hole by the main body, It does not get in the way and the screwing operation is always easy. Also, in the case where the packing ring is provided on the main body, the packing ring is inserted into the prepared hole when the screwing operation is performed, so that the main body of the screw is elastically pressed and the screw is prevented from falling off.

[0007]

【Example】

 Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. FIG. 1 is a front view showing an embodiment of the present invention, and FIGS. 2 and 3 are sectional views taken along lines 2-2 and 3-3 of FIG. 1, respectively. As shown in FIG. 1, the present embodiment has a screw portion 2 having a spiral groove 21 formed on the outer peripheral surface thereof, and a rotating head 6 provided at the rear end of the screw portion 2. The screw portion 2 and the head portion 6 are integrally formed of, for example, iron or synthetic resin, and the screw portion 2 is screwed into an object by rotating the head portion 6.

The screw portion 2 is composed of a cylindrical main body portion 2 a and a drill portion 3. The drill portion 3 has a relatively short axial length at the tip portion of the main body portion 2 a. The drill point 31 and the cutting edge 32 are formed at one end, and the other end is attached to the drill root 20. In addition to the spiral groove 21 formed on the outer peripheral surface, the cylindrical main body portion 2a starts from the drill point 31 (a portion where the drill comes into contact with an object) and has a rear end on the head 6 side. A chip escape groove 4 is also formed in a spiral shape so as to extend up to. The drill part 3 is formed with a front drill cutting blade 33, and the body part 2a is formed with a rear drill cutting blade 22. This rear drill cutting blade 22 has a larger radial dimension than the front drill cutting blade 33, so that the prepared hole formed by the front drill cutting blade 33 has a larger diameter than the rear drill cutting blade 22. It has become.

Further, in the main body portion 2 a of the screw portion 2, a concave groove 23 is formed at a position where a surface orthogonal to the central axis 10 intersects the outer peripheral surface, and the packing ring 5 is fitted in the concave groove 23. is doing. The packing ring 5 is made of an elastic material such as an O-ring, and when the screw is screwed into an object, the packing ring 5 enters the pilot hole together with the screw to prevent the screw from loosening or falling off. Therefore, the inner diameter of the concave groove 23 is smaller than the inner diameter of the circle formed at the bottom of the chip escape groove portion 4, and the outer diameter of the packing ring 5 fitted in the concave groove 23 is the outer diameter of the main body portion 2a. It is slightly larger than the outer diameter.

Next, the operation of the above embodiment will be described.

When the head 6 is rotated using a screwdriver or a spanner, first, the front drill cutting blade 33 of the drill hole 3 for the pilot hole punches the pilot hole in the object. The chips generated at this time are discharged through the chip relief groove portion 4 formed in the drill portion 3. Further, when the head portion 6 is rotated, the rear drill cutting blade 22 formed on the main body portion 2a expands the diameter of the prepared hole formed by the drill portion. The chips generated at this time are also discharged through the chip escape groove portion 4 formed in the main body portion 2a. Therefore, the chips do not enter between the screw portion and the inner peripheral wall of the pilot hole when the pilot hole is drilled by the drill portion 3 and the main body portion 2a is drilled. The screwing operation is always easy without any damage.

By this screwing, the spiral groove 21 formed on the outer periphery of the main body portion 2a bites into the inner peripheral wall of the prepared hole, and the tightening work is performed. The present invention is not limited to the above-described embodiments, but can be variously modified within the scope of the claims for utility model registration. For example, it is preferable that the material used for the screw has appropriate hardness, strength, and other mechanical characteristics, which can improve work safety and the life of the screw. . Further, the ratio of the lengths of the drill portion and the main body of the screw portion can be appropriately selected, and the shape of the head can be appropriately selected such as a hexagonal shape or a hexagonal hole. can do.

[0013]

[Effect of device]

 As described above, according to the present invention, the drill portion is provided at the tip of the screw portion and the chip escape groove portion extending from the tip of the drill portion to the rear end of the body portion is formed. Not only can the operations be performed at the same time, but the chips discharged from the drill can be reliably removed, and the chips do not interfere with the screwing operation. Further, since the packing ring is fitted to the main body of the screw portion, the screw does not loosen or fall off after screwing.

[Brief description of drawings]

FIG. 1 is a front view of an embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a sectional view taken along line 3-3 of FIG.

[Explanation of symbols]

2 ... screw part, 2a ... main body part
3 ... Drill part, 4 ... Chip escape groove part, 5 ... Packing ring, 6 ... Head part, 10 ... Central axis line, 21 ... Spiral groove, 22 ... Rear drill cutting blade, 23 ... Recessed groove, 31 ... Drill point, 32 … Cutting edge, 33… Front drill cutting edge.

Claims (3)

[Scope of utility model registration request] 1. A screw part having a spiral groove (21) formed on an outer peripheral surface thereof.
(2) and a screw having a head (6) for rotation provided at the rear end of the screw part (2), the screw part (2) includes a cylindrical body part (2a), A drill part (3) for a pilot hole provided at the tip of this body part (2a) and having a drill point (31) and a cutting edge (32), and a body part started from the drill point (31) (2a) has a chip escape groove (4) spirally drilled up to the rear end, and the front drill cutting blade (33) formed in the drill part (3) is attached to the main body part (2a). A screw having a pilot hole drill, characterized in that the length thereof in the radial direction is shorter than that of the formed rear drill cutting blade (22). 2. A main body portion (2a) of the screw portion (2) has a packing ring (23) formed in a concave groove (23) formed at a position where a surface orthogonal to a central axis (10) intersects an outer peripheral surface. The screw having the pilot hole drill according to claim 1, wherein the screw is fitted. 3. The inner diameter of the concave groove (23) is smaller than the inner diameter of a circle formed at the bottom of the chip escape groove portion (4), and a packing ring fitted in the concave groove (23). The screw having a pilot hole drill according to claim 2, wherein the outer diameter of (5) is slightly larger than the outer diameter of the main body (2a).