JPH05157107A - Self drill anchor - Google Patents

Abstract

PURPOSE: To provide an improved self-drilling anchor which is installable in a wall only by means of a screwdriver. CONSTITUTION: A shank section 10 has at its upper end a head 12 having a diameter larger than that of the shank section 10. The shank section 10 has a root 14, and a spiral threading is wound about the root 14. The anchor has a longitudinal bore threadably to receive a threaded member serving to hold an object against an outer surface of a wall. Integral with the shank section 10 and extending axially therefrom is a drill section 11 having at least one cutting blade 16A and guide blades 17A, B therefor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anchor, which is installed in a hole drilled in a wall and can accommodate a screw part for fixing a fixture or other object to the wall. More particularly, the present invention relates to a self-drilling anchor that requires no tools other than a screwdriver to install the anchor and can be used with screws of various lengths.

[0002]

BACKGROUND OF THE INVENTION For exterior surfaces of walls made of gypsum board, slab, fiberboard and other materials used in hollow wall construction,
Hollow anchors are commonly used for such purposes when mounting brackets, fixtures, or other objects having mounting holes. Traditional hollow anchors made of metal or plastic, when driven into a pre-drilled hole in the wall and secured, will be inserted into the fixture's mounting holes to accommodate threaded components or mounting screws that enter the hollow portion of the anchor Will be able to.

Which length of mounting screw is required depends on
It depends on the thickness of the fixture or the object to be hung on the wall. Therefore, when the object is a thin metal bracket, the required screw length is shorter than when the object is a thick plate that requires long screws.

Conventional anchor attachment is accomplished by three different movements. The first and most basic step is to drill a hole in the wall. At this time, the diameter of the hole should be approximately equal to the diameter of the anchor. If the diameter of the hole is too large, the next step of driving the anchor into the hole is that the anchor will not be firmly fixed and will be somewhat loose. As a result, the third step cannot be executed either.

In the third step, the threaded part has to be turned into the hollow part of the anchor. At this time, tap the anchor lightly. However, if the anchor is somewhat loose in the hole in the wall, when the screw part is turned, the anchor will rotate with it. Therefore, the screw cannot be turned into the anchor.

There may be a fourth step to consider. When it becomes necessary to remove an object mounted on the wall or change it to something else, first unscrew the anchor fixed to the wall. However, if a torque is applied to the screw when the screw is removed, this torque also rotates the anchor together with the screw, and the screw cannot be pulled out from the anchor. Therefore, there is a demand for an anchor that does not rotate counterclockwise when fixed in a hole drilled in a wall and that allows the threaded component to be removed from the installed anchor.

Conventional hollow anchors require three tools for installation. A drill with a drill bit whose diameter is approximately equal to the diameter of the anchor; a hammer for striking the anchor in a hole drilled in the wall; turning screw parts into and out of the anchor A screwdriver to do this.

[0008] People who do not work mainly for anchors or general households often have hammers and screwdrivers but do not have drills. Further, even if the user has a drill, it often does not have a drill bit that matches the diameter of the anchor to be attached.
However, the use of hollow wall anchors to attach objects to a wall offers many advantages over the use of screws, nails, and other threaded components. With such parts it is not necessary to drill holes in the wall, but their holding power is relatively weak and not particularly strong when used on walls made of fragile material. As described above, due to the presence of the drill, there have been various problems in the use of the hollow anchor by an amateur in the past.

Hollow wall anchors are used extensively by professional installers. It is very inconvenient in terms of practical use because it is necessary to drill a hole with a drill and drive the anchor into the hole, which requires a long working time and limits the number of anchors that can be attached within a certain time. further,
Drill bits that match the size of one anchor must be replaced with those for other anchors, such as when installing anchors of different sizes. Therefore, the time is wasted and the workability of the installer is deteriorated.

In order to solve such a drawback, 198
US Pat. No. 4,601,625 to Ernst et al. For 6 years. Drywall anchor with externally threaded cylindrical portion and unthreaded drill part. Is mentioned. This shaft part is for inserting a screw part. Only manual screwdrivers are required to attach such anchors. Therefore, no drill or hammer is needed. The upper part of the anchor has a thin head in cross section, and the head of the anchor attached to the surface of the dry wall is flush with the wall.

Ernst et al
Describes an anchor formed of zinc as an example, and another example discloses an anchor formed of a plastic material. Both embodiments include drill components that can be laterally offset as the mounting screws are inserted therein. Therefore, even when the object to be mounted on the wall has various thicknesses, it is possible to use one type of mounting screw or screw component having an appropriate length. Longer threaded components can be used if this becomes necessary.

Ernst et al
In that patent, the drill part has a notched free end,
It is formed by a flat blade defining a central spike and a pair of peripheral spikes on either side of the central spike. Such a central spike extends below the peripheral spike and therefore penetrates the surface of the drying wall first. The central spike has the function of maintaining the position of the rotating drill part as it is drilled by the peripheral spike. In fact, when a single blade is used to drill a hole in a brittle material such as a dry wall, the hole drilled by this blade is not a perfect circle. When such material is present in the center or around the guide spokes, the material will change the position of the blade. As a result, drilling is off center and the holes drilled are either too large or oval.

An anchor having an externally threaded shaft part in its pending application No. 396,109 (filed Aug. 21, 1989), entitled "Self Drilling Anchor for Walls" of the present invention. Is listed. The shaft part extends to a drill part having a guide tip. In contrast to the externally threaded parts of the Ernst et al. Cylinder, the shaft part of the Applicant's anchor has a root that tapers towards the drill part. , There is a thread cut around the bottom of this valley. The threading is a series of turns with the crest of the thread being substantially the same diameter as the diameter of the shaft part. With such a structure, the anchor can be screwed into a wall made of a fragile material. Furthermore, the crushed and powdered wall material has the advantage that it is pressed into the threaded portion with a relatively high density, increasing the strength of the shaft part around the shaft part and keeping it from the wall.

[0014]

The self-drilling anchor described in the applicant's ongoing application has a flange-like head that is not as thick as the Ernst et al anchor. is doing. Thus, both self-drilling anchors, when rotated and attached to the wall, do not have the resistance to rotate and slip, and the attached anchors are flush with the surface of the wall. However, it must be resistant to disengagement. When it becomes necessary to remove the mounting screws and screw parts from the anchor, these are rotated by a screwdriver and then removed, but this operation also rotates the anchor together. Therefore, the threaded component cannot be removed from the anchor.

In view of the above mentioned problems, the main object of the present invention is that it can be mounted on a wall using a screwdriver,
To provide an improved self-drilling anchor that fits securely onto fasteners or other threaded components for holding objects to the wall and does not require tools other than screwdrivers such as drills and hammers for mounting. It is in.

More particularly, it is an object of the present invention to provide an anchor having an externally threaded shaft part and a drill part extending from the shaft part. When screwing the anchor into the wall, drill parts are used to drill holes in the wall. This hole is lightly engraved by cutting the shaft part.

The invention is primarily characterized by an anchor threaded into a drill part having multiple cutting edges. Each cutting edge is associated with a guide blade to ensure that the drill component is screwed into the wall. The blade is moved to make a hole, but the cross section of this hole is circular and does not deviate from a circle or become oval. Therefore, if the hole is nicked by the shaft part of the anchor, an appropriate threading shape and maximum holding strength can be obtained.

The invention is also characterized by a shaft component.
The head of the axle piece presses against the wall surface when the anchor is attached to the wall. In addition, the head of the shaft component is provided with grip teeth that prevent the anchor from rotating and coming off.
If the threaded part needs to be removed from the anchor, the anchor will not disengage from the wall. Therefore, the problem that the screw component cannot be pulled out does not occur.

Another object of the present invention is to provide an anchor in which the drill part is bisected so as to be able to enter further into the threaded part if it is forcibly engaged by the tip of the threaded part when entering the shaft part. To do. By doing so, the length of the screw part to be used can be extended to the length of the shaft part.

Yet another object of the present invention is to provide an anchor having a drill part extending axially from an externally threaded shaft part. The drill part is a cylindrical core drill in which the holes are aligned with the holes of the shaft part. Thus, it is possible to thread the elongated threaded part from under the shaft part to the drill part.

Another object of the present invention is to provide an anchor in which the shaft component has a tapered bottom and a thread is cut around the bottom. The threading is a series of turns with the crest of the thread being substantially the same diameter as the shaft component. With this configuration, when the anchor is screwed into a wall made of a fragile material, the particles generated by the screwing work are pushed into the threaded portion with a relatively high density, and the shaft is rotated around the shaft part. The strength of the part is increased so that it does not come off the wall

Another object of the present invention is to provide a plastic anchor which can be manufactured relatively inexpensively using a material having high strength.

[0023]

In order to solve the above-mentioned problems, according to the present invention, there is provided a self-drilling anchor which can be attached to a wall by means of a screwdriver or similar tool, and which is attached to the upper part of the shaft part. Inserting the tool for screwing the anchor into the wall into the head, the head having a wider diameter than the shaft part, the shaft part having a valley bottom, and turning a spiral thread cut in the valley bottom. And has a longitudinal hole for threadably accommodating a screw part for holding an object with respect to the outer surface of the wall, and is integrally formed with the shaft part,
Screwing the anchor into the wall by the tool by having a drill part extending axially from the shaft part, the drill part comprising at least one cutting member and guide means for the cutting member Sometimes the cutting member digs through the wall to make a circular hole, the bank of holes engages the guide means to ensure the hole is circular, and the shaft part defines the head and wall. An anchor is obtained, characterized in that it penetrates into the hole and knurls it until it engages with the outer surface and the attachment of the anchor is completed.

In another embodiment of the invention, the drill portion is a core drill having one or more cutting teeth, the cylindrical outer surface of which serves as a guide means to secure the drilled holes. It has a round shape.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1-4, a self-drilling anchor according to the present invention is shown. The anchor shown in the drawing is formed by using a synthetic plastic material, and has a hollow shaft part 10 and a drill part 11 formed integrally with the shaft part 10.

The synthetic plastic material from which the anchor is molded must be strong and capable of sharpening the hollow wall material to which the anchor is attached by the blade when formed into the shape of a sharp blade. The wall is made hollow using gypsum board, slab, fiberboard or other material. Such materials are generally brittle. That is, it should be taken into account that the material is fragile when mounting anchors on such walls, as it will easily crumble.

The anchors are preferably reinforced with long glass fibers (about 30% by weight) and molded from nylon, which is a low cost moldable, ductile composite. The glass fiber as a component of the composite can provide the strength and rigidity required for the anchor, and also make the cutting edge of the drill part effective. actually,
Since the color of the composite material is natural or neutral, it matches the color of the surface of the hollow wall.

The hollow shaft component 10 accommodates an externally threaded screw component or a mounting screw, and mounts a bracket or a fixture having a mounting hole, a plate or other object to the surface of a wall on which the anchor is mounted. Hold. The length of the screw part is approximately the same as the thickness of the object to be held.

The shaft part 10 has an enlarged head 12 at the top, that is, a flange having no thickness. This flange is frustoconical in shape. When attaching the anchor to a hollow wall made of gypsum board or other relatively soft material, the head 12 sinks into the wall and becomes flush with the surface of the wall.

A radial array of ratchet teeth T is formed on the lower surface of the head 12. The ratchet tooth triangle is such that when the anchor is rotated clockwise and screwed into the wall, the tooth engages the wall. That is, the teeth rub in this direction unimpeded in rotation. However, counterclockwise movement of the anchor is impeded because the teeth engage the wall when attempting to rotate the anchor out. Due to this feature, even if it becomes necessary to remove the threaded component from the anchor mounted on the wall, the work of removing the threaded component does not cause the anchor to be removed together. This makes it difficult, if not impossible, to remove the threaded component from the anchor. The flange or head 12 is made of a composite material of nylon having a somewhat bent portion, so that the teeth T provided on the lower surface of the head bend when the anchor is screwed into the wall. Therefore, it does not scrape plasterboard or other wall materials.

The advantage of the anchor being flush with the wall on which it is mounted is that the head does not allow any space between the wall and the fixture or other object to be attached to the wall. In addition, it is not necessary to remove the anchor if you later remove the fixture from the wall or want to hide the anchor. All you have to do is repair the top of the head and clean the wall surface.

The shaft component 10 has a longitudinal cavity 13 therein. The cavity extends in the length direction of the shaft part and has a cross shape that defines a 90-degree peak R. For the ridge R surrounding the central portion of the cavity, the thread of the female screw can be cut by using a metal mounting screw or threading of a screw part. Therefore, it becomes possible to use not only screws having a predetermined diameter but also screws having various diameters within a limited range as mounting screws for the anchors. As will be described below, the drill component allows the screw to extend slightly below the shaft component so that the mounting screw can be adapted to fit fasteners or other objects of varying thickness that are wall mounted.
It may be longer than the length of.

The cruciform shape of the cavity serves as a socket for accommodating the blade of the screwdriver in the head portion 12 of the shaft component 10. This screwdriver is a Phillip type
s-type) or any other conventional screwdriver, either manually or electrically driven.

The shaft component 10 has a tapered bottom 14. On the other hand, the spiral threading 15 provided around the valley bottom
The convolution has a thread crest whose diameter is substantially the same as the diameter of the shaft part except for the last convolution 15F. This last convolution has a somewhat smaller diameter to connect to the drill 11. Therefore, there is no sudden transition from the drill part 11 to the shaft part 10.

The threading and the valley bottom are such that when the shaft part is screwed into the wall, the material that can be easily crushed becomes a dense mass that enters the shaft and prevents the anchor from slipping out of the wall. It is in.

The drill part 11 is provided with a pair of cutting edges 16A and 16B. These extend in opposite directions from the longitudinal axis X of the anchor, as best seen in FIG. Thus, the flat cutting edges E of these blades are diametrically opposed and act to scrape the wall and drill a hole H when screwing the anchor. A pair of guide blades 17A and 17B are provided at right angles to each cutting blade. This guide blade engages the bank of holes H so that the holes drilled in the wall are circular. At this time, the axis X of the anchor is collinear with the central axis of the hole.

The outer edge O _e of the guide blade has a convex shape. This causes the bank of holes to be curved, with the outer end slipping into the bank when turning the drill part. In this way, a circular hole is made in the wall, and Ernst et al.
The single-edged drill piece, as shown in the et al) patent, eliminates the possibility of creating oversized or oval holes.

Cutting blades 16A and 16B and guide blade 17A
The lower ends of 17B and 17B are chamfered. The lower end of the cutting blade, which is slightly longer than the guide blade, defines a triangular point P. Therefore, if you press the anchor against the surface of the wall,
The point P cuts into the surface. Further, when the torque generating tool is used to rotate the anchor, the wall surface is pierced by the cutting edge guided by the guide blade for keeping the shape of the hole circular.

In practice, the self-drilling anchor as shown in FIGS. 1-4 may be molded from materials other than synthetic plastic materials. For example, it may be formed of a metal having a corrosion resistance such as zinc or brass.

Referring to FIG. 5, an anchor according to the present invention mounted on hollow wall 18 is shown. Since the anchor shaft part 10 is longer than the wall thickness, a part of this shaft part extends from the inner surface of the wall.
The anchorless head 12 is flush with the outer surface of the wall. That is, the teeth T provided on the lower surface of the head 12
Is embedded in the material of the wall, and the anchor does not rotate and come off.

A mounting screw 19 for holding the fixture 20 against the wall surface is inserted into the hollow of the shaft component 10. The fixture 20 has a mounting hole 21 for inserting a screw.
have. The length of the mounting screw 19 is such that the tip of the screw fits in the conical recess 22 at the lower end of the cavity provided in the hollow shaft component 10 immediately above the drill portion. In practice, the cavity may be threaded laterally to insert the mounting screw, or when the mounting screw is screwed into the cavity without threading, it may be threaded into the cavity.

Since the mounting screw 19 fits closely into the cavity of the shaft part, when it is turned all the way below the shaft part, the drill part 11 is held in the shape shown in FIG.

However, when mounting the anchor as shown in FIG. 6, a longer mounting screw 23 is used which, when screwed into the shaft part 10, projects below the recess at the lower end of the cavity. In such a case, the drill part 11 is bisected and the mounting screw emerges from the shaft part. Since the drill part has already performed the function as a drill, even if the drill part is divided after the drilling, the attachment of the anchor is not affected. Furthermore, the halving of the drill part goes outside the wall, so that the holding force of the anchor is not affected.

It is not necessary to attach a notch or notch to the anchor to allow the mounting screw to be easily removed from the shaft part. The tip of the mounting screw fits into the conical recess of the cavity of the shaft part and penetrates the drill part from its center to bisect the drill part. At this time, it is considered that the two cutting blades and the guide blade are V-shaped.

In the anchor shown in FIG. 7, the mounting screw 2
When 3 is screwed into the shaft part 10 and the drill part 11, it breaks or shifts laterally from the shaft part rather than splitting as shown in FIG. In order to facilitate such movement, it is not necessary to provide a circular groove or notch at the joint between the shaft part of the anchor and the drill part. Since this joint part is originally weak, the drill part will be damaged if force is applied by screwing the mounting screw. Therefore, the mounting screw can be pushed out of the shaft part. In practice, the strength of the bridge between the two cutting edges of the drill part is determined when the drill part breaks into a triangle or breaks.

In FIG. 8, the anchor is attached to a double wall formed of a wall 18 and a wall 18 'having the same thickness. In this case, when the anchor is attached, the shaft part 10 does not extend to the inside of the hollow wall but is completely buried in the wall. As a result, the apex of the V-shape is in the wall 18 'when the drill part 10 breaks into a V-shape. Furthermore, the V-shaped wings act as toggles so that the anchor cannot come out of the wall. Therefore, the retention force of the anchor according to the invention is even stronger when mounted on a double wall, which is usually of high quality commercial construction.

Referring to FIGS. 9-12, a reusable self-drilling anchor according to the present invention is shown at 24. The anchor is molded from a synthetic plastic material such as nylon or a corrosion resistant metal such as zinc. The anchor has a hollow shaft part 25. Furthermore, the upper end is provided with a head 26 having a diameter larger than that of the shaft, that is, a frustoconical, non-thick flange. When the anchor is attached to a wall made of gypsum board or other relatively soft material, the head 26 is embedded within the wall and flush with the outer surface of the wall.

A radial array of teeth 27 is formed on the lower surface of the head 26. Preferably, the teeth are triangular ratchets and the teeth engage the wall when the anchor is rotated clockwise and screwed into the wall. That is, the teeth rub in this direction unimpeded in rotation. However, counterclockwise movement of the anchor is impeded because the teeth engage the wall when attempting to rotate the anchor out.

The shaft part 25 has a longitudinal hole 28 therein. This hole extends in the lengthwise direction of the shaft part and has a cross shape that defines a 90-degree rib or ridge 28R. On the ridge 28R that surrounds the central portion of the hole 28, the thread of the female thread can be cut by using a metal mounting screw or thread cutting of a screw component. Therefore, it becomes possible to use not only screws having a predetermined diameter but also screws having various diameters within a limited range as mounting screws for the anchors.

The cross shape of the hole serves as a socket for accommodating the blade of the screwdriver in the head portion 26 of the shaft component 25. This screwdriver is a Phillips-type
e), or any other conventional screwdriver, which may be manually turned or electrically driven.

The shaft component 25 has a tapered valley bottom 29. On the other hand, the spiral threading 30 provided around the valley bottom
The convolution is substantially the same as the diameter of the shaft part, except for the final convolution, which is somewhat smaller in diameter.

As described in another embodiment of the anchor according to the present invention, the threading and the valley bottom allow the easily crushable material to enter into a high-density mass around the shaft when the shaft part is screwed into the wall. , There is a relationship that prevents the anchor from falling out of the wall.

A cylindrical core drill component 31 is formed extending from the shaft component 25 in the axial direction and integrated with the shaft component 25. The outer diameter of the core drill component is the same as the outer diameter of the tapered valley bottom 29 at the bottom of the shaft component. Therefore, the bottom of the shaft part and the drill part are continuously connected. The longitudinal holes 32 of the drill part are aligned with the longitudinal holes 28 of the shaft part.

The diameter of the bore 32 is suitable for any mounting screw or threaded component that can score the bore 28 of a shaft component. As mentioned above, it is not necessary to use a threaded part with a predetermined diameter for the anchor, but for the anchor to have a diameter that allows the threaded part to penetrate the hole without causing distraction or breakage or defects. With regard to threaded parts, threaded parts with various diameters can be used within a limited range.

A conventional core drill is a hollow drill that removes a cylindrical core from a drill hole, such a core drill having a cylindrical drill blade that acts as a cutting element for the drill. There is.

In the core drill part 31 according to the invention, the drill blade for this drill part is composed of a pair of diametrically opposed cutting teeth T ₁ and T ₂ . Each tooth is defined by a triangular curved wall. The beveled edges of the triangle serve as the cutting edges and the tips of sharp nails and sharps.

Thus, as shown in FIG. 13, when the anchor is pushed into a typical wall made of a relatively soft material, the points P ₁ and P ₂ of the core drill part penetrate the wall and these points Corresponds to both poles having a diameter D of a hole H to be drilled. This diameter is equal to the diameter of the cylindrical core drill part.

The outer surface of the core drill component acts as a guide, and the holes drilled by the drill are always circular. This is because when the core drill part is screwed into the wall blank using a screwdriver, the teeth T ₁ and T ₂ of the drill blade advance while making a circular hole, the shape of which is defined by the cylindrical outer surface. This is because it has been done.

When a hole is drilled in the wall W by a drill part and then the anchor is rotated by a screwdriver, the anchor part is brought into engagement with the surface of the wall as shown in FIG. The shaft parts of the will enter into this hole.

The length of the self-drilling anchor depends on the thickness of the hollow wall in which the anchor is mounted. This is because for most materials the drill part 31 projects from the back of the wall when the anchor is installed and before the threading of the shaft part engages with the drilled hole to score the hole. To do so. In FIG. 14, the shaft component 2
The length of 5 is longer than the wall thickness. Therefore, the lower side of the shaft component projects from the wall.

In order to hold the fixture 33 on the outer surface of the wall W, the threaded screw component 34 is inserted from the attachment hole of the fixture into the hole of the shaft component and the screw is turned. At this time, the screw part goes into the inside while making a hole. Fixture 34
Is longer than the anchor. Therefore, when the fixture is rotated and screwed in, it passes through the hole in the shaft part and into the hole in the cylindrical core drill part. Further, as shown in FIG. 14, the screw comes out of the drill part.

In such a self-drilling anchor,
Nothing else blocks the passage of the threaded parts other than the crushed wall material core that has entered the holes of the core drill part. Furthermore, if the threaded part penetrates under the shaft part, it will push the core of crushed material out of the drill part. At this time, the drill parts are not adversely affected and the drill parts are not broken to form the passage.
Therefore, the anchor remains completely intact. Furthermore, if it becomes necessary to remove the anchor from the wall later, it can be easily removed. Therefore, the anchor can be reused.

The preferred embodiments of the self-drilling anchor according to the present invention have been described above with reference to the drawings.
It can be easily understood that various changes and modifications can be made without departing from the basic gist of the present invention. Therefore, instead of forming the drill blade of the core drill component with a pair of opposed teeth, it is also possible to use a circular array of teeth as the drill blade.

[0064]

As described above, according to the present invention,
It can be attached to the wall using only a screwdriver, which has the effect of providing an anchor that fits a screw component for holding fixtures or other objects on the wall.

[Brief description of drawings]

FIG. 1 is a perspective view showing a self-drilling anchor according to the present invention.

FIG. 2 is a plan view showing an anchor according to the present invention.

FIG. 3 is an enlarged perspective view of a drill part of an anchor according to the present invention.

FIG. 4 is a cross-sectional view showing a drill component of an anchor according to the present invention, which is a view for explaining a relationship between a cutting blade and a guide blade.

FIG. 5 shows an anchor mounted on a hollow wall, with a threaded threaded part of the anchor having the same length as the shaft part but not extending below the shaft part. It is a figure which shows the state inserted inside.

FIG. 6 shows an anchor mounted with a threaded component of such length that it breaks and opens the drill component.

7 is a view similar to FIG. 6 except that the drill part is broken by the screw part.

FIG. 8 is a view showing a state where the drill part of the anchor is broken by using the same screw part as that of FIG. 6, and is a view showing a case where the anchor is attached to the double wall.

FIG. 9 is a perspective view of a self-drilling anchor having a core drill component according to the present invention.

FIG. 10 is a front view of the anchor.

FIG. 11 is a vertical sectional view of an anchor.

12 is a transverse cross-sectional view of a portion indicated by line 12-12 in FIG.

FIG. 13 is a diagram showing a relationship between holes formed by a drill and drill parts.

FIG. 14 shows an anchor attached to a hollow wall with a threaded component that extends below the anchor.

[Explanation of symbols]

 10 Shaft Parts 11 Drill Parts 12 Head 15 Screw Cutting 16 Cutting Blade 17 Guide Blade 18 Wall 19 Mounting Screw 20 Fixing Tool 21 Mounting Hole

Claims (10)

[Claims] 1. A self-drilling anchor that can be attached to a wall by means of a screwdriver or similar tool, comprising: (a) a head having a diameter larger than that of the shaft part at the top of the shaft part; The tool for screwing into the wall is inserted into the head, the shaft part has a root, the spiral thread is turned on the root, and for holding an object against the outer surface of the wall (B) a drill part formed integrally with the shaft part and extending in the axial direction from the shaft part, the drill part having at least one drill part; By providing a cutting member and guide means for the cutting member, the cutting member drills a circular hole into the wall when the anchor is screwed into the wall by the tool, and the bank of holes is Engaging the guide means with the hole The shaft part is surely circular, and the shaft part enters the hole and knurls the hole until the head is engaged with the outer surface of the wall to complete the attachment of the anchor. Drill anchor. 2. The self-drilling anchor of claim 1, wherein the anchor is molded of synthetic plastic material. 3. The self-drilling anchor of claim 1, wherein the anchor is made of a metal having corrosion resistance. 4. The drill part comprises a cylindrical core drill having a longitudinal hole aligned with the hole of the shaft part, the drill having a drill cutting edge and a cylindrical outer surface functioning as a guide means. 2. The self-drilling anchor according to claim 1, further comprising: a threaded part that can be threaded into the hole of the shaft part, and that allows a threaded part longer than the shaft part to penetrate the hole of the drill part. 5. A self-drilling anchor attachable to a wall with a screwdriver or similar tool, comprising: (a) threadably housing a threaded component for holding an object against the outer surface of the wall. An externally threaded shaft part having a hole in the longitudinal direction, the upper part of the shaft part having a head having a diameter larger than that of the shaft part, and containing the tool for screwing the anchor into the wall, (B) comprising a substantially cylindrical core drill component integrally formed with the shaft component and extending axially from the shaft component, the drill component being substantially the hole of the shaft component. With a longitudinal hole aligned with a threaded part threadably insertable into the hole of the shaft part and longer than the shaft part, the drill part being defined by at least one cutting tooth Equipped with a drill blade By,
Rotation of the tool when screwing the anchor into the wall causes the teeth to dig a hole in the wall to make a hole, and the cylindrical outer surface of the drill component acting as a guide means ensures that the hole is circular. A self-drilling anchor, characterized in that the threaded shaft part is inserted into the hole and the hole is scored until the head of the shaft part is flush with the outer surface of the wall. 6. The shaft component has a tapered valley bottom integrally formed with the cylindrical drill component, and a diameter of the valley bottom and a diameter of the drill component are different at a joint point with the drill component. Self-drilling anchor according to claim 5, characterized in that they are equal. 7. The head is frustoconical and comprises an array of teeth on a lower surface of the head that engages a surface of the wall to prevent rotation of the anchor. 5
Self-drilling anchor as described. 8. The self-drilling anchor according to claim 5, wherein the tooth has a triangular shape, and the slanted end of the triangle forms a cutting edge. 9. The self-drilling anchor according to claim 5, wherein the longitudinal hole provided in the shaft part is threaded by the threaded part. 10. The self-drilling anchor of claim 5, wherein the anchor is formed of nylon.