WO2018159697A1

WO2018159697A1 - Expanding-type anchor and expanding member used therein

Info

Publication number: WO2018159697A1
Application number: PCT/JP2018/007570
Authority: WO
Inventors: 敏次濱田
Original assignee: 敏次濱田
Priority date: 2017-02-28
Filing date: 2018-02-28
Publication date: 2018-09-07
Also published as: JPWO2018159697A1; JP6972104B2

Abstract

This anchor is a split-tip type of anchor in which a slit 2 opens to a distal end surface 3a of an expanding part 3, and the expanding part 3 expands in diameter due to balls 4 pushed by a bolt 6. The inner peripheral surface of the expanding part 3 is straight. Therefore, the entire expanding part 3 expands in diameter straightly throughout a wide range. Because the entire expanding part 3 expands in diameter, protruding (or wedging) in a lower hole 10 is satisfactory. As a result, high pull-out resistance is exhibited.

Description

Expandable anchor and expansion member used therefor

The present invention relates to an expandable anchor suitable for use in a stone-based member such as concrete or brick, and an expandable member used for this.

Extensible anchors are used as a means of attaching various members to concrete structures such as buildings and tunnels. In general, the expandable anchor is formed in a tip-breaking manner in which a plurality of slits are opened to the distal end surface, and it is common to strike a tapered pin and expand it.

However, in the method of hitting the pin, there are problems such as an inability to adjust the opening degree of the extension part, and a problem that a great burden is imposed on the swinging up of the hammer. In particular, in the case of construction on a ceiling surface, the hammer must be lifted upward, so that the burden on the operator is very large.

On the other hand, with regard to the expandable anchor, a method has been proposed in which a ball is pushed with a bolt to expand the expanded portion, and examples thereof are disclosed in

Patent Documents

1 and 2. Further, the applicant of the present application disclosed in Patent Document 3 an example in which the diameter of the expanded portion is increased by a group of balls, taking as an example a closed-type anchor having a closed tip portion.

Japanese Utility Model Publication No. 4-27209 microfilm JP 2004-218421 A PCT / JP2016 / 52833

As in Patent Documents 1 to 3, in the method of expanding the extended portion by pushing the ball with a bolt, the extent of expansion of the extended portion can be adjusted, so that the pullout resistance can be easily adjusted. In addition, since the bolt can be easily rotated by a power driver or the like, there is an advantage that the burden on the operator can be reduced even when it is installed on the ceiling surface. Furthermore, in the structure of patent document 3, since the pressing force of an expansion part acts from the direction orthogonal to the pilot hole, there exists an advantage that the cone fracture | rupture of concrete can be suppressed.

The present invention has been made on the basis of such a current situation, and intends to provide an improved anchor by effectively utilizing the idea of Patent Document 3.

The present invention includes an expandable anchor and an expansion member used therefor, and each includes various configurations.

The first invention relates to an expandable anchor, and this expandable anchor is
"It is an expandable anchor that is used by inserting it into a pilot hole vacated in the construction department,
It has a cylindrical main body formed with an extension part on the front end side, a plurality of balls arranged in the main body, and a bolt that pushes the plurality of balls toward the front end side of the extension part. ,
One or a plurality of slits are formed in the extended portion so as to facilitate extending the diameter of the extended portion in a direction perpendicular to the axis so as to extend long in the longitudinal direction of the extended portion. ,
When the ball is pushed toward the distal end side of the extended portion, the expanded portion expands and stretches into the prepared hole. ''
It is the basic composition.

And in addition to the above basic structure,
“The expansion portion includes a cylindrical portion in which the ball is movably disposed and has a substantially straight inner diameter, and a stopper portion that is continuous with the tip of the cylindrical portion and holds the ball in an unremovable manner. And forming the slit so that the stopper portion is also divided and opened to the tip surface of the extension portion, so that the stopper portion and the cylindrical portion are joined together by pushing the ball with the bolt. The diameter can be expanded to
At least one ball is arranged so as to hit the stopper portion.
The structure is added.

The second invention is a development example of the first invention, and in this invention, the outer peripheral surface of the expanded portion is formed in a tapered shape.

The third invention is a development example of the first invention or the second invention, and in this invention, a protrusion having a cross-sectional mountain shape is formed on the outer peripheral surface of the expansion portion.

The fourth invention is an example of the development of the first invention.
“In the inside of the cylindrical part, a rod-shaped intermediate member that does not expand and deform is disposed so as to be movable in the axial direction, and one or more balls are disposed on both front and rear sides of the intermediate member.”
It is the composition.

The fifth invention is directed to an expansion member used for an expandable anchor. That is, this invention
“A group of expansion members that are loaded inside the expandable anchor and are unitized as a whole by a package or other holding means”
It is the composition.

In the expandable anchor of the present invention, since the expanded portion is pushed straight by the group of balls and expands in a straight shape, the pilot hole in the construction portion such as concrete can be pressed over a wide area as in Patent Document 3. Although estimated to be due to this, it is possible to prevent or greatly suppress the cone breakage in which the construction portion is detached in a trapezoidal cross section.

In addition, when compared with the closed method exemplified in Patent Document 3, if the length of the extension portion is the same, the total length of the anchor can be shortened in the present invention, so that the cost can be suppressed and the processing of the pilot hole can be performed. Time and effort can be reduced. Furthermore, since it is a tip cracking method, the inner surface of the construction part can be strongly pressed by effectively utilizing the pressing force caused by screwing in the bolt to spread the expansion part. Thereby, it can be said that high pull-out resistance can be secured.

Now, since the anchor is stretched and stretches into the pilot hole of the construction part, when you try to pull it out, the resistance gradually increases according to the drawing dimension, and finally it will come out of the pilot hole (the construction part is If not destroy).

However, the feature of the expandable anchor of the present invention is that the resistance required to pull out the unit length is larger than that of the hammered anchor. That is, assuming that 5 mm is pulled out, the magnitude of the resistance in the present invention is larger than that of the hammer-type anchor. Alternatively, when the anchor is pulled with the same force, the anchor of the present invention has a smaller moving amount than the hammer-type anchor. This means that the anchor of the present invention is less likely to slip out (not slippery) from the pilot hole.

As an evaluation of the performance of an expandable anchor, there are the maximum resistance to pulling out and the amount of movement when a unit load is applied. Usually, the load on the anchor is set to a fraction of the maximum resistance in consideration of the safety factor. Therefore, it can be said that it is advantageous to hold the workpiece stably as it is difficult to come off (non-slip) as in the present invention.

And in this invention, although the outer peripheral surface may have the taper shape, the cylindrical part of an expansion part is basically straight as a whole. For this reason, due to the diameter expanding action by the group of balls, most of the expanded portion tends to expand (swell) in a straight shape.

Therefore, compared with the case where the extended portion spreads and deforms in a trumpet shape, it is possible to increase the bite into the pilot hole and make it difficult to come out from the pilot hole. Further, since the expandable anchor of the present invention is a tip-breaking method in which the slit is open to the tip, it is possible to expand the diameter of the expanded portion as a whole (swelling deformation) from the closed method (first-closed method). Can be done with light force. Alternatively, when the bolt is tightened with the same torque, the tension force against the pilot hole can be made larger than in the closed method. Also in this aspect, high fastening strength can be secured by effectively using the screwing force of the bolt.

In the second invention, it was useful for improving the pull-out resistance. The reason is not necessarily elucidated, but it is presumed that when the pulling force of the anchor is increased, the resistance by the group of balls is also increased. Or since the expansion part spreads and becomes easy to deform | transform because thickness becomes small toward a front-end | tip, it is estimated that the tensile force with respect to the pilot hole of a construction part is also increasing.

When the protrusion is formed in the extended portion as in the third aspect of the invention, the protrusion can bite into the pilot hole in the construction portion, thereby improving the pull-out resistance and stabilization. In addition, since it becomes easy to bite into a construction part, so that a protrusion is high in hardness, it is useful to perform surface treatment so that the surface hardness of a protrusion may become high at least.

Now, the inventors of the present application have repeated trial manufactures and experiments, but when a large number of balls are put into the expansion part, when the ball is pressed with a bolt, the expansion part does not expand so much and the ball collapses and deforms. Was seen. That is, there was a phenomenon in which the pressing force by the bolt was consumed for deformation of the ball, and the diameter of the expanded portion became insufficient.

And, the ball tends to be greatly crushed at the portion close to the bolt. Therefore, even if the bolt is screwed in, the group of balls located near the bolt is crushed into one lump, and this lump is formed. As a result, the ball group becomes clogged with the base of the extension (the end opposite to the stopper), and as a result, even if the bolt is screwed in, the pressing force of the bolt cannot be transmitted to the ball on the tip side. Sometimes occurred. In this case, only the base portion close to the bolt in the expanded portion has a large diameter (swells), and on the distal end side, there is room for expansion, but the diameter expansion is insufficient.

This phenomenon is because the hardness of the ball is low. When a ball having a hardness that does not crush and deform at all is used, the pressing force of the bolt is transmitted to the ball at the tip, so that the diameter of the expanded portion can be expanded as a whole.

However, since the ball of the present invention requires toughness, the use of a ball having excellent toughness and hardness increases the cost. Therefore, in consideration of economic efficiency, a device that can expand the diameter of the expanded portion as a whole while using a ball having a certain degree of hardness is required.

The fourth invention responds to this demand. In the fourth invention, the pressing force of the bolt is transmitted to the ball group on the tip side via the intermediate member, so that it is expanded on both sides before and after the intermediate member. The part is expanded. As a result, even if an excessively hard ball is not used, it is possible to ensure a high fastening strength by expanding the diameter of the extended portion as a whole. A plurality of intermediate members can be provided apart in the axial direction.

In the fourth invention, it is also possible to arrange a group of balls of the same diameter on both sides before and after sandwiching the intermediate member, but when using a single large-diameter ball and a small-diameter ball group as in the embodiment, The large-diameter balls exerted the pressing function in the axial direction, and the group of small-diameter balls exhibited the function of expanding the expanded portion, and the action of expanding the expanded portion as a whole was promoted. Therefore, the bolt tightening force is effectively used for expanding the diameter of the expanded portion, thereby greatly contributing to the improvement of the fastening strength. In this case, as in the embodiment, it is preferable to form the distal end portion of the intermediate member into a tapered portion having a tapered shape because the expansion action of the expansion portion by the group of small diameter balls can be promoted.

When manufacturing an expandable anchor, it is necessary to load an expansion member such as a ball on the main body. However, when the expansion member is loaded manually, it is troublesome to load the expansion anchor one by one. Moreover, it cannot be said that there is no mistake in the number and size. In this respect, in the fifth invention, since the expansion member such as a ball is unitized so as not to be separated, the expansion anchor can be assembled accurately and easily.

1A and 1B are views showing a first embodiment, wherein FIG. 1A is a side view, FIG. 1G is a longitudinal side view, FIG. 1C is a CC view of FIG. 1A, and FIG. (E) is a longitudinal side view in a fully expanded state, and (G) and (F) are cross-sectional views showing examples of use. It is a figure which shows an effect, (A) is a graph which shows the relationship between a drawing dimension and drawing resistance, (B) is an external view of this-application embodiment, (C) is an external view of a prior art example. It is a figure which shows 2nd Embodiment, (A) is a side view of an external appearance, (B) is a vertical side view in an expanded state. (A) is a side view of the main part of the third embodiment, (B) is a view taken along the line BB of (A), (C) is a diagram showing the action, and (D) is a diagram showing the action of the fourth embodiment. (E) is the principal part side view of 5th Embodiment. (A) is a side view of the sixth embodiment, (B) is a BB view of (A), (C) is a cross-sectional view of the main part of the seventh embodiment, and (D) is a side view of the eighth embodiment. (E) is a side view of the ninth embodiment, and (F) is a side view of the tenth embodiment. It is a figure which shows embodiment regarding the holding means of an expansion member, (A) is process drawing of 11th Embodiment, (B) is the isolation | separation figure of 12th Embodiment, (C) is the fragmentary figure of 13th Embodiment. . (A) is a vertical side view of the fourteenth embodiment, (B) is a vertical side view of the fifteenth embodiment, (C) is a side sectional view of the sixteenth embodiment, and (D) is a vertical side view of the seventeenth embodiment. (E) is a cross-sectional view taken along line EE of (D), and (F) is a cross-sectional view taken along line FF of (D). It is a figure which shows 18th Embodiment, (A) is a vertical side view in the state before preliminary diameter expansion, (B) is a vertical side view in the state after preliminary diameter expansion, (C) is the first of the constriction method. (D) is a longitudinal side view showing a second aspect of the constriction method. It is a figure which shows a reference example, (A) is a side view in a 1st process stage, (B) is a side view in a 2nd process stage, (C) is a side view in a 3rd process stage, (D) is a use condition. FIG.

Next, an embodiment of the present invention will be described with reference to the drawings. Hereinafter, the expandable anchor is simply referred to as “anchor”.

(1). First Embodiment First, the first embodiment shown in FIG. 1 will be described. The anchor is used for a concrete structure, for example, and includes a main body 1 made of steel. In addition, the main body 1 can also be made from other metals according to a use.

The main body 1 has a hollow cylindrical shape, and an extended portion 3 having four slits 2 is formed on the tip side. That is, by forming the four slits 2, the extended portion 3 is formed on the distal end side. Four slits 2 are formed at equal intervals in the circumferential direction, and each of the slits 2 opens on the distal end surface 3a of the extension portion 3 (or the main body 1). Therefore, the expandable anchor has a tip cracking method. Moreover, the expansion part 3 is an aggregate of strips (bands) from which the slits 2 are divided.

The inside of the main body 1 is filled with a large number of balls 4 for expanding the diameter of the expanded portion 3. A female screw 5 is formed on the inner periphery of the main body 1, and a bolt 6 for pushing the group of balls 4 is screwed into the female screw 5. Although the balls 4 are displayed in the same size, in practice, it can be said that it is preferable to fill a plurality of types of balls having different outer diameters and to make the inside as dense as possible. The bolt 6 does not have a head and has an engagement hole into which the wrench 7 is fitted at one end. The female screw 5 can be formed over the entire length of the main body 1.

An inward stopper portion 8 that prevents the ball 4 from coming off is formed at the tip of the main body 1. Therefore, the stopper portion 8 is also divided into four by the slit 2. The inner peripheral surface 3 b of the extension part 3 is formed straight except for the stopper part 8. In other words, the portion of the expansion portion 3 excluding the stopper portion 8 is a straight cylindrical portion having a constant inner diameter and outer diameter (equal thickness). Therefore, most of the extended portion 3 is a straight cylindrical portion.

After the anchor is inserted into the pilot hole 10 of the concrete construction part (mating member) 9 and the bolt 6 is screwed with the wrench 7, the group of balls 4 is in the axial direction and the radial direction (direction perpendicular to the axis). When pushed, the expanded portion 3 expands (swells) so that its outer diameter increases. As a result, the expansion portion 3 is strongly stretched to the pilot hole 10 (the construction portion 9), and the anchor is fixed to the pilot hole 10. Since the extended portion 3 has a straight shape on both the inner periphery and the outer periphery, the pressing force by the balls 4 acts substantially uniformly over the entire length of the extended portion 3. For this reason, in the state in which the ball 4 is ideally expanded in diameter without being crushed and deformed at all, the expanded portion 3 is straight in the expanded state, and a slight range of the base end portion becomes the tapered portion 11. ing.

The work fixing method may be selected according to the application. FIG. 1F shows a state in which the suspension bolt 12 is attached. The suspension bolt 12 is fixed to the main body 1 with a nut 13. FIG. 1G shows a state in which a member 14 such as a metal fitting is fixed with a bolt 15.

(2). Evaluation FIG. 2A shows the relationship between the drawing size and the drawing resistance when a drawing load is applied in the same state for the first embodiment and the conventional product 16. . In the graph of (A), the vertical axis represents the pulling resistance, and the unit is N, for example. The horizontal axis is the drawing dimension, and the unit is, for example, mm. E is that of the first embodiment, and P is a conventional product. S1 is a load actually used.

As shown in (C), the conventional product 16 is an anchor that is expanded by a pin 17, and the expanded portion 3 extends in a tapered shape. In (B), the anchor of the first embodiment is schematically displayed. Both the product of the present embodiment and the conventional product do not move until a certain load is applied, and starts moving after exceeding a certain load.

Although the embodiment product of the present application and the conventional product 16 have variations, the increase rate of the drawing resistance S with respect to the increase rate of the drawing dimension R (that is, the inclination angle θ of the line) shows that the embodiment product of the present application is compared with the conventional product 16. Θ is small, and this point is consistent with each sample. That is, the embodiment product of the present application is much smaller than the conventional product 16 in the dimension of moving in the pulling direction when the same load is applied.

Regarding the maximum value of the pull-out resistance, the conventional product 16 may be excellent, or the embodiment of the present application may be excellent, and variation was observed. In actual use, it is used with an expectation of several times the safety factor. Therefore, in the normal use state, the product of the embodiment of the present invention does not move in the pulling direction at all or moves very little. The member can be stably held. On the other hand, the conventional product 16 tends to slip out at a large rate when the load reaches a certain level, and can be said to be slippery.

Furthermore, the feature of the present embodiment product is that when the pulling force increases to a certain extent, the amount of movement increases while maintaining the maximum resistance. On the other hand, in the conventional product 16, when the pulling force reaches a certain level, the pull-out resistance decreases while the amount of pull-out increases. Therefore, in the present embodiment, a high resistance is maintained until the anchor is completely pulled out, and the holding force is high.

The reason why θ is small in the embodiment of the present application is presumed to be that the angle of the taper portion 11 at the base of the expansion portion 3 is large, and the root strongly bites into the pilot hole 10. Moreover, since the anchor moves while the root of the expansion part 3 is biting into the pilot hole 10, it is estimated that the maximum resistance is maintained.

On the other hand, since the conventional product 16 is weakly hooked to the pilot hole 10, the ratio of the moving amount to the load increase rate is large (θ is large), and the frictional resistance of the expansion portion gradually decreases while moving. Finally, it is speculated that the resistance will drop rapidly. That is, it can be estimated that the conventional product 16 is easy to slide the pilot hole 10, but the cause is not clear.

(3). Second embodiment (FIG. 3)
In the second embodiment shown in FIG. 3, the outer peripheral surface 3c of the expansion part 3 is formed in a tapered shape before the expansion. The inner peripheral surface 3b has a straight shape. Therefore, the thickness of the extended portion 3 decreases toward the tip. However, as a whole, the shape is close to straight. In this embodiment, when the expansion part 3 is pushed by the ball 4, the outer peripheral surface of the expansion part 3 is in close contact with the pilot hole 10. It becomes a taper shape that spreads forward.

Now, when the anchor moves in the pulling direction due to the load, the resistance acts strongly on the taper portion 11 at the base. For this reason, as shown by the arrow 18 in FIG. Then, the ball 4 tends to move to the tip side as indicated by an arrow 19. Then, as indicated by an arrow 20, the distal end portion of the expansion portion 3 is pushed by the ball 4 and tries to expand so as to increase the radius (expansion is attempted). That is, when the anchor moves in the pulling direction, the ball 4 tends to expand the expansion portion 3 in a tapered shape. Thereby, it is estimated that high extraction resistance is exhibited.

When the balls 4 have hardness and toughness that do not deform at all, a complete ball hitting phenomenon occurs, and the pressing force of the bolts 6 acts on each ball 4. Therefore, the expansion part 3 expands uniformly (swells) while maintaining a straight shape. However, when the balls 4 are crushed and deformed, the group of balls 4 positioned at the base end portion of the extended portion 3 may be crushed into a state of being in close contact with each other, and may be in a lump state. In this way, when the group of balls 4 is in a lump state at the base end portion of the expansion portion 3, the entire expansion portion 3 can be evenly expanded in diameter without the pressing force of the bolt 6 acting on the distal end side. It is not possible to obtain the intended pulling force.

In this respect, in the present embodiment, the expansion portion 3 has a slightly low hardness because the ball 4 is easily moved to the tip side by expanding the inner diameter in a tapered shape. The pressing force of the bolt 6 can be made to act strongly on the ball 4 on the tip side. Therefore, the uniform diameter expansion of the expansion part 3 can be promoted. Thereby, it can be said that the drawing resistance can be improved.

Further, when the expansion portion 3 moves in the pulling direction, the expansion portion 3 tries to constrict, but since the inner diameter of the expansion portion 3 is widened, the group of balls 4 has a strong resistance to the deformation of the expansion portion 3. Acts as In this respect as well, it can be said that the high resistance against drawing is exhibited.

(4) Third to fifth embodiments (FIG. 4)
In the third embodiment shown in FIG. 4A, a plurality (four) of annular (square or rectangular) annular grooves 21 are formed in the extended portion 3. The annular groove 21 located closest to the proximal end is located closer to the distal end than the proximal end of the slit 2. In this embodiment, since the strength of the portion of the annular groove 21 is weakened, the portion of the annular groove 21 is bent as shown in FIG. Thereby, it can be said that the

edges

21a and 21b constituting the opening edge of the annular groove 21 bite into the pilot hole 10 (into the construction portion 9) and exhibit a high pulling resistance.

The fourth embodiment shown in FIG. 4 (D) is a modification of the third embodiment. In this embodiment, the annular groove 21 has an edge 21a that is angular only on the distal end side, and the proximal end side is inclined. It becomes the surface 21c and is formed in the substantially trapezoid as a whole. In this embodiment, since only the edge 21a on the base end side greatly bites into the prepared hole 10 (the construction portion 9), it can be said that the pull-out resistance is further increased. The annular groove 21 may be a triangle (a right triangle).

The fifth embodiment shown in FIG. 4E is also a modification of the third embodiment. In this embodiment, the annular groove 21 is formed in a square or rectangular square (rectangular shape) as in the third embodiment. The annular groove 21 (19 ′) located on the most proximal side is disposed at the proximal end of the slit 2.

In this embodiment, in the diameter-expanded state, the state is bent at the position of the annular groove 21 (21 ') located closest to the base end side, so the position of the annular groove 21 (21') positioned closest to the base end side It can be said that the edge 21a on the front end side of the plate bites into the pilot hole 10 strongly. Therefore, it can be said that a high pull-out resistance can be ensured also in this embodiment. The groove width of the annular groove 21 (21 ′) located on the most proximal side can be made larger than that of the other annular grooves 21.

The number of slits 2 can be set arbitrarily. It is also possible to divide the extended portion 3 into two portions, the distal end side and the proximal end side, and to make the number of slits different between the proximal end side and the distal end side. For example, three slits 2 are formed on the base end side, and six slits are formed on the distal end side by adding three other slits in addition to the extension of the slit 2 on the base end side. It is possible to do. It is also possible to fit a ring made of a hard material into the annular groove 21.

(5) Sixth to tenth embodiments (FIG. 5)
In the sixth embodiment shown in FIGS. 5A and 5B, the outer peripheral surface of the expansion portion 3 is formed in a tapered shape, and the pilot hole 10 (the construction portion 9, The protrusion 23 which bites into (concrete) is formed. The circumferential length of the protrusion 23 is set to a dimension far smaller than the width of the strip-shaped piece sandwiched between the slits 2 in the extended portion 3. Moreover, the protrusion 23 is formed in a triangular mountain shape in order to improve the bite into the concrete.

The group of protrusions 23 is formed on the strips separated by the slits 2 at equal intervals in the axial direction. The adjacent strip-shaped projections 23 are arranged in the circumferential direction, but the adjacent strip-shaped projections 23 may be arranged so as to be shifted in the axial direction (a staggered arrangement may be used).

The main body 1 is manufactured from a material whose outer peripheral surface is straight, and in forming the outer peripheral surface of the expansion portion 3 in a tapered shape, first, an annular protrusion is formed by leaving the portion of the protrusion 23, and then forming an annular protrusion. The protrusion 23 having a small width is formed by partially cutting a part of the annular protrusion with a cutter or a grindstone. That is, the material is cut so that the portion of the protrusion 23 remains. Therefore, the diameter of the circumscribed circle of the protrusion 23 is the same as the material diameter of the main body 1. Further, the protrusion 23 closer to the tip is higher in height.

In this embodiment, when the diameter of the expansion portion 3 is increased by the group of balls 4, the outer peripheral surface of the expansion portion 3 is in close contact with the pilot hole 10 of the construction portion 9, and each projection 23 is in the pilot hole 10 (concrete). Bite. Thereby, an extremely high pulling resistance can be realized. And since the main body 1 is manufactured with the straight material, it is very easy to form the protrusion 23, and manufacture is easy. Moreover, since an outer peripheral surface is a taper shape, the same effect as 2nd Embodiment is exhibited.

In the seventh embodiment shown in FIG. 5C, the protrusion 23 has a cross-sectional shape of a right triangle in which an inclined surface is formed only on the tip side. For this reason, it can be said that the pull-out resistance is further increased. This form is applicable to each embodiment provided with the protrusion 23. The width dimension, the number of arrangement, the height, and the cross-sectional shape of the protrusion 23 can be arbitrarily set.

5 (D) and 5 (E), the thickness of the expansion portion 3 is smaller than that of other portions. However, by setting both the outer diameter and the inner diameter to a small diameter, the thickness of the expansion portion 3 is reduced. It is also possible to set the same dimensions as other parts. In (A), when the inner peripheral surface is also formed to have a tapered shape, the expanded portion 3 can be formed to have an equal thickness over the entire surface.

In the sixth embodiment of FIG. 5 (A), the extended portion 3 is formed in a tapered shape. However, in the eighth embodiment of FIG. 5 (D), the entire extended portion 3 is a straight having a slightly smaller diameter than other portions. Is formed. Therefore, each protrusion 23 has the same height. Also in this embodiment, the entire extension portion 3 excluding the root is uniformly expanded in diameter, and each protrusion 23 bites into the pilot hole 10. And since each protrusion 23 is the same height, it can be said that extraction resistance becomes still higher.

In the ninth embodiment shown in FIG. 5 (E), the extended portion 3 is formed in a straight shape slightly smaller in diameter than the other portions except for the portion of the stopper portion 8, and a large number of protrusions 23 are formed on the small diameter portion. Forming. In this embodiment, in use, the small diameter portion swells and deforms, and each protrusion 23 bites into the pilot hole 10. Also in this case, since each protrusion 23 is the same height, a high extraction resistance can be ensured.

In FIG. 5F, in the tenth embodiment, the protrusions 23 are left in a ring shape and are separated by the slits 22. That is, the protrusion 23 is formed over the entire width of the strip. When a plurality of protrusions 23 (projections) are formed on each strip, the one that extends over the entire width of the strip and the one that is smaller than the width of the strip are alternately formed in the circumferential direction. Is also possible. Alternatively, the protrusion 23 can be formed only at one position in the axial direction.

Each embodiment of FIG. 5 uses the deformation of the expansion portion 3 to cause the projection 23 to bite into the pilot hole 10, and the projection 23 is the reference outer peripheral surface of the main body 1 (the outer peripheral surface of the material) before the expansion. ), The insertion of the pilot hole 10 has no problem at all. Moreover, if the expansion part 3 is expanded to some extent, the protrusion 23 bites into the pilot hole 10 and the protrusion 23 becomes non-rotatable, so that the expansion operation is easy.

(6). Eleventh to thirteenth embodiments (FIG. 6)
Now, as in the present invention, when a plurality of balls 4 are used as the diameter expanding means of the expansion portion 3, it is necessary to accurately load a predetermined number of balls of a predetermined size. In this case, it is possible to hold the balls 4 separately in the main body and then hold the bolts 6 so that they cannot be detached. However, in the loading operation, the number of balls 4 inserted may be wrong due to carelessness. A problem is assumed. In particular, when a plurality of types of balls having different sizes are used, it can be said that erroneous loading is likely to occur.

Therefore, in the embodiment of FIG. 6, the group of balls 4 is unitized so as not to be separated by the holding means, and the unitization is loaded into the main body 1, thereby assembling reliability and ease. ing.

In the eleventh embodiment shown in FIG. 6A, a resin tube is used as the holding means. That is, using a long strip raw fabric 30 in a strip shape, one end is sealed to form the bottom 31, and at the same time, the package is cut into a package (unit tube) 32 of a predetermined length, After the group of balls 4 is put into 32, the opening 33 is closed by heat sealing or the like and sealed.

That is, after a predetermined number of balls 4 have been put into the hopper, the tip of a chute such as a cylinder is inserted into the opening edge of the packaging body 32, and then the shutter is opened and a group of balls is thrown into the packaging body 32. Then, the opening of the package 32 is sealed. This process can be automated as a whole or manually.

When the long tube raw material 30 is used, first, the bottom portion is formed by heat sealing or the like, and then a group of balls 4 is inserted to close the opening portion by heat sealing or the like. And then closing the opening, and then cutting the package 32 enclosing the balls 4 from the tube stock 30 and simultaneously forming the bottom of the next package 32 by heat sealing. Can be adopted.

In the twelfth embodiment shown in FIG. 6B, a bottomed cylindrical case 34 is prepared as a holding means (holding tool), and a group of balls 4 is inserted into the case 34 and then closed with a cap (lid) 35. It is out. In this embodiment, the case 34 is loaded inside the main body 1. The cap 35 may be forcibly fitted. The case 34 and the cap 35 may be made of resin or paper.

Further, in the thirteenth embodiment shown in FIG. 6C, the adhesive 36 is used as the holding means, the balls 4 are joined together with the adhesive 36, and the entire group of balls 4 is unitized into one unit. ing. As another holding means, for example, a group of balls may be immersed in UV resin, and the UV resin may be cured with ultraviolet rays and integrated.

When using a bag as the holding means, it is also possible to use a rubber bag. In this case, since the entrance is widened, there is an advantage that the ball can be easily inserted. Whether it is a bag or a tube, the opening can be sealed by connecting the bag itself.

(7). Fourteenth to seventeenth embodiments (FIG. 7)
FIG. 7 shows an embodiment in which the intermediate member 38 is used. In these embodiments, the structure of the main body 1 is the same as that of the first embodiment, for example (the number of slits 2 may be three or four).

In the fourteenth embodiment shown in FIG. 7 (A), a solid rod-like intermediate member 38 made of steel or the like is disposed in the expansion portion 3, and one large-diameter ball 4a is provided on both the front and rear sides of the intermediate member 38. And a plurality of small-diameter balls 4b. The distal end portion of the intermediate member 38 is formed in a tapered portion 38a that is tapered. Further, in front of the intermediate member 38, the large and

small balls

4a and 4b are arranged such that the large-diameter ball 4a is located in front (closed to the stopper portion 8) and the group of small-diameter balls 4b is located behind ( (It is close to the intermediate member 38).

On the other hand, the

balls

4a and 4b located behind the intermediate member 38 are arranged such that the small-diameter ball 4b is located in front and the large-diameter ball 4a is located behind. In addition, a shaft-like pusher 39 that pushes the large-diameter ball 4a located behind is disposed on the main body 1. It is also possible to push the rear large-diameter ball 4 a with the bolt 6 without using the pusher 39.

In the fifteenth embodiment shown in FIG. 7 (B), only the small-diameter ball 4b is disposed at a location in front of the intermediate member 38.

In the embodiment of FIGS. 7A and 7B, the small-diameter ball 4b moves in the radial direction on both the front and rear sides of the intermediate member 38, so that the expanded portion 3 is indicated by a one-dot chain line in FIG. In addition, the diameter is expanded evenly as a whole, or the diameter is expanded so as to be widened as shown by a two-dot chain line in FIG. When the diameter expansion action before and after the intermediate member 38 is the same level, the diameter is expanded like a one-dot chain line, and when the diameter expansion action in front of the intermediate member 38 is high, the diameter is expanded like a two-dot chain line. It can be said that.

7 (A) and 7 (B) is characterized in that the rear small-diameter ball 4b moves in the radial direction when the large-diameter ball 4a is pushed, and the rear large-diameter ball 4a is intermediate. The pressing force can be made to act strongly on the

balls

4a and 4b in front by contacting the rear surface of the member 38. Therefore, the rear surface of the intermediate member 38 is preferably a flat surface orthogonal to the axis. The formation of the tapered portion 38a at the front end portion (front portion) of the intermediate member 38 greatly contributes to ensuring that the small-diameter ball 4b located in front of the intermediate member 38 moves in the radial direction. is doing.

If a large-diameter ball 4a is disposed in front of the intermediate member 38 and is brought into contact with the stopper portion 8, the ball 4b can be prevented from coming out of the stopper portion 8 when the expansion portion 3 is expanded in diameter. Is preferred.

In the sixteenth embodiment shown in FIG. 7C, the

balls

4a and 4b, the intermediate member 38, and the pusher 39 of the fourteenth embodiment are unitized into one unit by a tube-shaped packaging body 32. Therefore, the assembly work can be performed accurately and easily.

In the seventeenth embodiment shown in FIGS. 7D to 7E, a plurality of

wedge bodies

40a and 40b arranged in the circumferential direction are integrally provided on both front and rear sides of the intermediate member 40, and are surrounded by the

wedge bodies

40a and 40b. Only the large-diameter ball 4 is disposed in the broken part. The front wedge body 40a is divided into six equal parts, and the rear wedge body 40b is divided into three equal parts. Therefore, the rear wedge body 40b is not easily deformed. The fractions of the

wedge bodies

40a and 40b can be arbitrarily set.

Each

wedge body

40a, 40b has a radial thickness that decreases from the proximal end toward the distal end. For this reason, the group of the

wedge bodies

40a and 40b constitutes a tapered tube whose inner surface is widened. Accordingly, the

wedge bodies

40a and 40b are bent and deformed so as to spread in the radial direction by the pressing action of the ball 4a, and as a result, the expanded portion 3 is expanded in diameter.

(8). Eighteenth embodiment (FIG. 8)
In the eighteenth embodiment shown in FIG. 8, the expansion portion 3 is once spread and deformed with a tool, and then is narrowed so as to enter the prepared hole 10. In (C), the slit 2 is narrowed so as to remain open, and in (D), the slit 2 is closed by being closed. In this embodiment, it can be said that the diameter expansion at the time of construction can be facilitated by the curved portion being attached to the expanded portion 3.

(9) Reference example (Fig. 9)
FIG. 9 shows a reference example regarding a closed anchor. In this reference example, in a closed type anchor in which the slit 2 does not open to the distal end surface, a plurality (two) of engaging bodies 51 extending rearward are formed in the extended portion 3 in the circumferential direction. The engaging body 51 is surrounded by the slit 2 except for its root. Therefore, the engagement body 51 is in the form of a cantilever beam extending backward.

As a manufacturing method, the material is processed so as to have a portion to become the engaging body 51 as shown in (A), and then the slit 2 is formed as shown in (B), whereby the cantilever-like engaging body 51 is formed. Then, the engagement body 51 is pushed and bent inward as shown in (C).

The engaging body 51 has a radial thickness that increases toward the free end. Therefore, the engagement body 51 has a long claw shape in the axial direction. In a state before use, the engaging body 51 is bent inward so as not to protrude to the outer periphery of the expansion portion 3, and in use, the engaging body 51 is formed in a tapered shape with a tapered tip. It is spread with a bolt 6. In this embodiment, as the pulling force increases, the engagement body 51 bites into the pilot hole 10 and can be expected to exhibit a very strong resistance to pulling.

In the figure, the engaging body 51 is expanded with the bolt 6, but the taper pin (wedge member) can also be pressed with the bolt 6. Alternatively, it is possible to drive the taper pin with an impact hammer without using the bolt 6. In the figure, the engagement body 51 is in the form of a cantilever, but it can also project from the extended portion 3.

(10). Others While the embodiments of the present invention have been described above, the present invention can be embodied in various ways. For example, the anchor can be formed in a polygonal shape or an elliptical shape instead of a cylindrical shape (perfect circle shape). As a work attachment means, it is also possible to form a male screw at the base end of the main body and press and fix the member to the construction part with a nut screwed into the male screw.

The number of slits may be one. It is also possible to form the slit in a posture inclined with respect to the axial center (or a posture twisted around the axial center). The unitization of the expansion member by the holding means can also be applied to the expansion member used in the closed type anchor.

The invention of the present application can be embodied in an anchor for concrete and its expansion member. Therefore, it can be used industrially.

DESCRIPTION OF SYMBOLS 1 Main body 2 Slit 3 Expansion part 3a Tip surface 3b Inner peripheral surface 3c Tapered outer

peripheral surface

4, 4a, 4b Ball 5 Female screw 6 Bolt 8 Stopper part 9 Construction part (partner material, concrete)
DESCRIPTION OF SYMBOLS 10 Pilot hole 32 Package as example of holding means for unitization 34 Case as example of holding means for unitization 38 Intermediate member 39 Pusher

Claims

It is an expandable anchor that is used by inserting it into a pilot hole opened in the construction part,
It has a cylindrical main body formed with an extension part on the front end side, a plurality of balls arranged in the main body, and a bolt that pushes the plurality of balls toward the front end side of the extension part. ,
One or a plurality of slits are formed in the extended portion so as to facilitate extending the diameter of the extended portion in a direction perpendicular to the axis so as to extend long in the longitudinal direction of the extended portion. ,
When the ball is pushed toward the front end side of the extension part, the extension part expands in diameter and extends into the pilot hole,
The extension portion includes a cylindrical portion in which the ball is movably arranged and has a substantially straight inner diameter, and a stopper portion that is continuous with the tip of the cylindrical portion and holds the ball in an unremovable manner. And forming the slit so that the stopper portion is also divided and opened to the tip surface of the extension portion, so that the stopper portion and the cylindrical portion are brought together by pushing the ball with the bolt. The diameter can be expanded,
At least one ball is disposed so as to hit the stopper portion,
Expandable anchor.
The outer peripheral surface of the extension portion is formed in a tapered shape that is tapered.
The expandable anchor according to claim 1.
On the outer peripheral surface of the extension part, a protrusion having a cross-sectional angle is formed,
Being
The expandable anchor according to claim 1 or 2.
Inside the cylindrical portion, a rod-shaped intermediate member that does not expand and deform is disposed so as to be movable in the axial direction, and one or more balls are disposed on both front and rear sides of the intermediate member,
The expandable anchor according to claim 1.
A group of expansion members to be loaded inside the expandable anchor, which are unitized as a whole by a package or other holding means;
Expansion member used for expandable anchors.