INJECTION NOZZLE FOR USE IN PINNING METHOD

AND PINNING METHOD USING THE SAME

Technical Field

This invention relates to an injection nozzle for use in a pining method which is employed in repairing a wall body such as an outer wall or an inner wall in which a so-called "separation" has occurred, and also relates to a pinning method using the injection nozzle. Background Art

As this kind of injection nozzle, there is known one which is made up of: a nozzle main body (body itself) having a resin flow passage formed along an axial center thereof; and an injection needle (nozzle inner cylinder) the base end portion of which is held by the nozzle main body and which is in communication with the resin flow passage ^r and has formed therein an injection passage (see JP-A-2003/147971) . In this case, the nozzle main body is made of fluororubber and has at its front end portion a tapered portion for sealing an opening portion of a charging hole. On the other hand, as a pinning method using this injection nozzle, there is known one comprising: a boring step of boring a charging hole in a portion to be repaired of an outer

wall made up of a finishing material (tile, stone, or the like) , mortar, and concrete framework; a resin injection step of injecting an adhesive resin (adhesive) into the bored charging hole by using a resin injector which is equipped with an injection nozzle; and a pin charging step of charging an anchor pin into the charging hole into which the resin has been injected.

In this case, in the resin injection step, when the injection nozzle of the resin injector is inserted into the bored charging hole and is urged, the tapered portion is brought into close contact with the opening portion of the charging hole to thereby seal it. When the resin injector is operated (pumped) in this state, the resin is gradually filled into the charging hole from the innermost portion thereof and is spread over separated portions between the concrete framework and the mortar. By performing pumping for a given number of times, the injection of resin is finished. However, with this kind of injection nozzle, in case the separated portions have occurred not only between the concrete framework and the mortar but also between the mortar and the finishing material, the air is vented through the "separated" portions. As a result, the resin is likely to be first spread only to the separated portions between the concrete and the

mortar, and there is thus a possibility that the resin will not reach the "separated" portion between the mortar and the finishing material. In such a case, it was necessary to inject the resin to such a portion while withdrawing the injection nozzle. However, at the time of withdrawing the injection nozzle, the sealing at the opening portion of the charging hole is released. As a result, there is a problem in that the resin cannot sufficiently be spread to the "separated" portion between the mortar and the finishing material.

Disclosure of Invention

As a solution, this invention has an object of providing an injection nozzle for use in a pinning method which can sufficiently inject an adhesive even to the shallow portion on the near side of a charging hole, and a pinning method using the injection nozzle. According to one aspect of this ^' invention, there is provided an injection nozzle for use in a pinning method, the injection nozzle being arranged to be mounted on an injector main body while in use, the pinning method being performed by injecting an adhesive into a charging hole bored through a wall member to a predetermined depth, while sealing an opening portion of the charging hole, the injection nozzle comprising: a nozzle body to be mounted on the injector main body

and having therein an adhesive passage in communication with the injector main body; and a nozzle inner cylinder held by the nozzle body in a state of projecting from a front end of the nozzle body and having a discharge port at a front end thereof and a first injection passage communicating the discharge port with the adhesive passage, wherein a second injection passage is formed in a clearance between an inner cylinder holding portion of the nozzle body for holding the nozzle inner cylinder and the nozzle inner cylinder, the second injection passage being communicated with the adhesive passage and being open toward a front end portion of the nozzle body.

In this case, it is preferable that the first injection passage and the second injection passage be configured such that, at an initial stage of injecting the adhesive, a flow resistance of the adhesive flowing through the first injection passage is smaller than that of the adhesive flowing through the second injection passage.

According to the above configuration, when the adhesive is injected into the charging hole while sealing the opening portion of the charging hole by the nozzle body, the adhesive is first discharged out of the discharge port through the first injection passage of the nozzle inner cylinder and is gradually filled

from the innermost portion of the charging hole. The adhesive will soon reach a separated portion between the concrete framework and mortar and flows into the separated portion. At substantially the same time, the adhesive is discharged out of the front end portion of the nozzle body through the second injection passage which is provided in the clearance between the nozzle body and the nozzle inner cylinder and is filled into the charging hole from the near side thereof. The adhesive will soon be spread over the shallow portion on the near side of the charging hole, such as the separated portion between the mortar and the finishing material, or the like.

In this case, it is preferable that the nozzle body comprise: a nozzle main body which holds the nozzle inner cylinder and which seals the opening portion of the charging hole with a peripheral surface thereof; and mounting fittings for mounting the nozzle main body on the injector main body, wherein the nozzle main body is made of an elastic material.

According to this configuration, when the nozzle body is urged against the opening portion of the charging hole, the peripheral surface of the nozzle main body comes into close contact therewith and, at the same time, the elastic material is appropriately deformed, thereby sealing the opening portion. As a

result of this sealing, the returning of the adhesive from the charging hole is blocked, whereby the adhesive can be filled in proper quantities. By the way, the elastic material is of such a nature as to allow for a slight deformation under the pressing force of an operator and does not, therefore, block the second injection passage.

In this case, it is preferable that the nozzle body comprise: a nozzle main body which holds the nozzle inner cylinder and which seals an opening portion of the charging hole with a peripheral surface thereof; and mounting fittings for mounting the nozzle main body on the injector main body, wherein the nozzle main body comprises a nozzle outer cylinder which constitutes the inner cylinder holding portion and a sealing member which encloses the nozzle outer cylinder and which seals the opening portion, wherein the nozzle outer cylinder is made of a hard resin ^' material or a metallic material, and wherein the sealing member is made of an elastic material.

According to this configuration, when the nozzle body of the injection nozzle is urged against the opening portion of the charging hole, the peripheral surface of the nozzle main body comes into close contact therewith and, at the same time, the elastic material is appropriately deformed, thereby sealing the

opening portion. As a result of this sealing, the returning of the adhesive from the charging hole is blocked, whereby the adhesive can be filled in proper quantities. Further, since the nozzle outer cylinder is of a hard material, the second injection passage can be prevented from deforming due to the urging by the nozzle body. The flow amount, the flow resistance, etc. of the adhesive can be stabilized.

In this case, it is preferable that the elastic material be fluororubber .

According to this configuration, since fluororubber is solvent-resistant, deterioration with time by the adhesive can be prevented.

In this case, it is preferable that the nozzle inner cylinder be held by the inner cylinder holding portion in a freely advancing and retracting manner.

According to this configuration, when the adhesive is injected, the nozzle inner cylinder advances in the injecting direction relative to the nozzle body due to the viscous resistance (flow resistance) of the adhesive which flows through the first injection passage inside the nozzle inner cylinder. Since the nozzle inner cylinder consequently comes into abutment with the innermost portion of the charging hole, the adhesive can always be injected from the innermost portion of the charging hole, even if the

charging hole may vary in depth. Accordingly, there is no possibility that an air pocket is formed in the innermost portion of the charging hole. Alternatively, the nozzle inner cylinder may be extended to the maximum extent so as to bring it into abutment with the innermost portion of the charging hole (retract) and, thereafter, the adhesive is injected.

According to another aspect of this invention, there is provided a pinning method for repairing a wall member by using an adhesive injector having the above- described injection nozzle for use in a pinning method and the injector main body on which the injection nozzle is detachably mounted, the method comprising the steps of: boring the charging hole by boring through the wall member to a predetermined depth; injecting the adhesive into the charging hole while sealing an opening portion of the charging hole by means of the adhesive injector; and charging an anchor pin into the charging hole having the adhesive injected therein. According to this configuration, after the charging hole has been bored in the place of the wall member which must be repaired, the adhesive is injected by the adhesive injector from the innermost portion of the charging hole. Thereafter, the anchor pin is charged into the innermost portion of the charging hole into which the adhesive has been filled. In this case,

since there is used the above-described injection nozzle having the first injection passage and the second injection passage, the adhesive will be injected from the side of the innermost portion of, and from the side of the opening of, the charging hole. In this manner, it is possible to sufficiently spread the adhesive into the separated portion, e.g., between the concrete framework and mortar as well as between the mortar and the finishing material. As described hereinabove, according to this invention, since the adhesive can be injected through the second injection passage also from the side of the opening portion of the charging hole, the adhesive can sufficiently be injected into the shallow portion on the near side of the charging hole such as the

"separation" which has occurred in the space between the mortar and the finishing material. It is therefore possible to perform complete repairs of the wall member in which the "separation" has occurred.

Brief Description of Drawings

Fig. 1 is a sectional schematic view in which an adhesive injector having an injection nozzle for use in a pinning method relating to an embodiment of this invention is used for a charging hole formed in an outer wall;

Fig. 2 is a plan view of the adhesive injector;

Figs. 3A and 3B are a plan view of the injection nozzle and a sectional view of the injection nozzle, respectively; Fig. 4 is a plan view of an anchor pin;

Figs . 5A to 5C are a procedural diagram of a boring step, a first procedural diagram, and a second procedural diagram of an adhesive injection step, respectively, in the pinning method relating to this embodiment;

Figs . 6A to 6C are procedural diagrams of a third step, a fourth step, and a fifth step, respectively, of the adhesive injection step;

Figs. 7A to 7C are a procedural diagram of an anchor pin charging step, a procedural diagram of an anchor pin charging step relating to a first modified example of the anchor pin, and a procedural diagram of an anchor pin charging step relating to a second modified example of the anchor pin; and Fig. 8 is a sectional view of an injection nozzle relating to a second embodiment of this invention.

Best Mode for Carrying Out the Invention With reference to the accompanying drawings, a description will now be made about an injection nozzle for use in a pinning method as well as about a pinning

method using the same relating to an embodiment of this invention. In this pinning method, an injection nozzle of an adhesive injector is inserted into a charging hole which is bored into that portion to be repaired of an outer wall of a building structure, an inner wall (wall body) of stairwell, a hall, or the like at which a "separation" has occurred. An adhesive is then injected into the charging hole and, thereafter, an anchor pin is filled thereinto, thereby repairing the separation. A description will now be made about an example in which this repairing is made on an outer wall of a building structure.

Fig. 1 is a schematic view of a case in which the adhesive injector is used with an outer wall. As shown in Fig. 1, the outer wall 1 of a building is made up, as seen from the left side of the Fig., of: a concrete framework 2 which serves as a base; mortar 3 which is adhered to the surface thereof; and a finishing material 4, such as tiles or the like, which is adhered thereto. The space between the concrete framework 2 and the mortar 3 has given rise to a first separated portion (clearance) 6, and the space between the mortar 3 and the finishing material 4 has given rise to a second separated portion 7. For the purpose of repairing them, the outer wall 1 has formed therein a charging hole 8 which is penetrated into the finishing

material 4 and the mortar 3 and bored to a predetermined depth of the concrete framework 2. By injecting into the charging hole 8 an adhesive R with an adhesive injector 10 and by charging an anchor pin 70 (see Figs. 4 and 7A to 7C) thereinto, the repairing of the outer wall 1 is performed.

With reference to Fig. 2, a description will be made about the adhesive injector 10. The adhesive injector 10 is made up of: an injector main body 15 which forms the main part and is of a pump type to supply the adhesive R; and an injection nozzle 16, for use in the pinning method, which is detachably mounted on a front end portion of the injector main body 15. The injector main body 15 is provided with: a cylindrical casing 18 which extends to the base end side; a pump main body 19 on which is detachably mounted the casing 18; and a substantially L-shaped lever 20 which is held by the pump main body 19. The casing 18 has filled therein the adhesive R. The pump main body 19 has set thereto the casing 18 from the right side as seen in the Fig. and has mounted thereon the injection nozzle 16 from the left side as seen in the Fig.. The injector main body 15 is thus arranged to discharge the adhesive R from the injection nozzle 16 by a certain amount through the manual operation

(pumping) of the lever 20. As the adhesive R an epoxy

resin which is of adhesive base is used. Instead of limiting to the above, there may be used an inorganic adhesive having viscosity, or the like.

The injection nozzle 16 is made up, as shown in Figs. 3A and 3B, of a nozzle inner cylinder 25 which is located on the side of the front end and is small in diameter; and a nozzle body 26 which constitutes the main part of the injection nozzle 16. The nozzle body 26 is made up of: a nozzle main body 27 which holds the base end side of the nozzle inner cylinder 25; and mounting fittings 28 for mounting on the injector main ^' body 15 the nozzle main body 27 in a state of holding it.

The mounting fittings 28 are made up of: a joint member 29 which is screwed with the pump main body 19 of the injector main body 15; and a cylindrical fastening member 30 for fixedly mounting the joint member 29 on the nozzle main body 27. ^' The injection nozzle 16 is engaged with the nozzle main body 27 with the base end side of the nozzle inner cylinder 25 being in a nested manner. The front end side of the joint member 29 is inserted into the base end side of the nozzle main body 27, and the fastening member 30 is put on the top from the front end side of the nozzle main body 27, and then the fastening member 30 is screwed into the joint member ^' 29, thereby assembling the

injection nozzle 16.

The nozzle inner cylinder 25, which is formed into the shape of a syringe needle by using a metallic pipe such as stainless steel, or the like, or a resin pipe, is held inside the nozzle main body 27 in a manner to be slidable (movable back and forth) and is made up of: a discharge port 35 which opens at the front end portion; and a restriction portion 36 which is formed at the base portion thereof. A first injection passage 37 which communicates from the restriction portion 36 to the discharge port 35 is formed along the axis of the nozzle inner cylinder 25. This first injection passage 37 is communicated with an adhesive passage (to be described hereinafter) of the joint member 29 through the restriction portion 36. The discharge port 35 is slantingly cut to form an opening which is elliptical in cross-section. It is thus so arranged that, even in a state in which the front end portion of the nozzle inner cylinder 25 is brought into abutment with the innermost portion of the discharge hole 28, the discharge port 35 is not blocked, whereby the adhesive R can adequately be injected. The restriction portion 36 is formed to expand like a funnel to facilitate the introduction of the adhesive R which flows from the adhesive passage 58, and also to prevent the injection nozzle 16 from dropping out of

position at the time of pulling it out. In addition, the length of the nozzle inner cylinder 25 is arranged to be longer (by about 100 mm) than the distance between the innermost portion of the charging hole 8 and a slip-prevention portion 51 of the nozzle outer cylinder 40 (to be described hereinafter) in a state in which the discharge port 35 is brought into abutment with the innermost portion of the charging hole 8. The diameter of the nozzle inner cylinder 25 is formed, e.g., into 2 mm in outside diameter and 1.8 mm in inner diameter .

The nozzle main body 27 is made up of: a nozzle outer cylinder 40 into which is loosely fitted the nozzle inner cylinder 25; and a sealing member 41 which encloses the nozzle outer cylinder 40. The sealing member 41 is made of fluororubber and is integrally formed of: a tapered portion 43 which is formed into a taper to become smaller toward the front end side; a cylinder portion 44 which is connected to the tapered portion 43 and is formed into a cylindrical shape; and a large-diameter portion 45 which is larger in diameter than the cylinder portion 44. In this case, since the fluororubber is solvent-resistant, the deterioration thereof with the lapse of time can be prevented. On the inside of the large-diameter portion 45, there is provided a cylindrical mounting groove 46 into which is

fit a plug portion 55 of the joint member 29 (to be described hereinafter) in such a manner as to leave the base end portion open. In addition, in the axis from the tapered portion 43 to the cylinder portion 44, there is provided a through hole 47 which communicates with the mounting groove 46 and which is smaller in diameter than the mounting groove 46.

The nozzle outer cylinder 40 is formed into a cylindrical shape with a metallic pipe such as stainless steel, or the like, or a resin pipe and is fitted into the above-described through hole 47. The nozzle outer cylinder 40 is formed slightly longer than, and is slightly larger in diameter than, the through hole 47. Therefore, when the nozzle outer cylinder 40 is inserted under pressure into the through hole 47 so as to align with the base end portion of the through hole 47, the front end portion thereof protrudes slightly beyond the front end portion ^' of the tapered portion 43. The nozzle outer cylinder 40 will thus be held by the through hole 47 in a state of being firmly fitted therewith. It is also possible to make the length of the nozzle outer cylinder 40 equal to the through hole 47 so that the front end portion of the nozzle outer cylinder 40 and the front end portion of the tapered portion flush with each other. Further, it is also possible to make the nozzle outer cylinder 40

and the through hole 47 equal in diameter so as to bring the nozzle outer cylinder 40 in hermetically sealed abutment with the through hole 47. According to this configuration, the nozzle outer cylinder 40 prevents the second injection passage 52 from getting deformed due to urging, thereby stabilizing the flow amount and flow resistance of the adhesive R.

Around the front end portion of the nozzle outer cylinder 40, a leak port 50 of the second injection passage 52 to be described later is formed at a space between the nozzle outer cylinder 40 and the nozzle inner cylinder 25. The nozzle inner cylinder 25 is loosely fitted into the axis of the nozzle outer cylinder 40 so as to extend over the entire length thereof. The second injection passage 52 which is in communication with the leak port 50 is formed in the clearance between the nozzle inner cylinder 25 and the nozzle outer cylinder 40. In other words, at the nozzle main body 27 the nozzle inner cylinder 25 and the nozzle outer cylinder 40 are in the form of a double tube with the first injection passage 37 being configured on the inner surface of the nozzle inner cylinder 25 and the second injection passage 52 being configured in the clearance between the nozzle inner cylinder 25 and the nozzle outer cylinder 40. At the time of injecting the adhesive, the discharge port 35

which opens at the front end of the nozzle inner cylinder 25 lies opposite to the innermost portion of the charging hole 8, and the leak port 50 which opens at the front end of the nozzle outer cylinder 40 lies close to opening portion of the charging hole 8.

Further, the second injection passage 52 is, similar to the first injection passage 37, in communication with the adhesive passage 58 in the joint member 29 through the slip-prevention portion 51. In this case, too, the slip-prevention portion 51 guides into the second injection passage 52 the adhesive R flowing from the adhesive passage 58 and, at the same time, prevents the nozzle outer cylinder 40 from slipping out of position. The nozzle outer cylinder 40 is formed into a shape, e.g., about 40 mm in length, 3 mm in outer diameter and 2.6 mm in inner diameter. The above- described first injection passage 37 and the second injection passage 52 are configured such that, at the initial period of injecting the adhesive R, the flow resistance of the adhesive R to be flowed through the first injection passage 37 becomes smaller than that of the adhesive R to be flowed through the second injection passage 52. In other words, at the initial stage of injecting the adhesive R, the adhesive R is mainly injected through the first injection passage 37 and, at the point of time in which the adhesive R has

reached the first separated portion 6 between the concrete framework 2 and the mortar 3, the adhesive R is then injected mainly through the second injection passage 52. In more concrete, as shown in Figs. 5A to 5C and Figs. 6A to 6C, when the nozzle body 26 is urged against the opening portion of the charging hole 8, the opening portion is sealed. At the same time, the front end portion of the nozzle body 26, i.e., the leak port 50, lies in front of the second separated portion 7.

When the adhesive R is injected into the charging hole 8 while maintaining the sealed state, the nozzle inner cylinder 25 first advances in the injecting direction due to the viscous resistance (flow resistance) of the adhesive R which flows through the first injection passage 37 in the nozzle inner cylinder 25 and due to the injection force of the adhesive R which is received by the restriction portion 36. Once the nozzle inner cylinder 25 has come into abutment with the innermost portion of the charging hole 8, due to the fact that the flow resistance of the first injection passage 37 is smaller at the initial stage of injection, the adhesive R is discharged from the discharge port 35 through the first injection passage 37, whereby the adhesive R is gradually filled into the charging hole 8 from the innermost portion thereof. The adhesive R

will soon reach the first separated portion 6 between the concrete framework 2 and the mortar 3, thereby- flowing to spread over the entire portion of the first separated portion 6. When the adhesive R is further injected, the flow resistance in the first injection passage 37 becomes large due to the adhesive R that has already flowed thereinto. The adhesive R will then be discharged out of the leak port 50 through the second injection passage 52 which is not under the influence of the internal pressure, whereby the adhesive R comes to be filled from the near side of the charging hole.8. The adhesive R will soon be spread over the entire portion of the second separated portion 7 between the mortar 3 and the finishing material 4, thereby being filled into the first separated portion 6 and the second separated portion 7 in proper quantities.

As shown in Figs. 3A and 3B, the joint member 29 is formed of a metallic material such as stainless steel, steel, or the like, and is integrally made up of: a plug portion 55 which is fitted into the mounting groove 46 in the sealing member 41; a large-diameter screwed engagement portion 56 which is larger in diameter and is connected to the base end side of the plug potion 55; and a small-diameter screwed engagement portion 57 which is connected to the base end side of the large-diameter screwed engagement portion 56. In

addition, the adhesive passage 58 which is in communication with the injector main body 15 is formed through the axis of the joint member 29. As described hereinabove, the adhesive passage 58 is in communication with the first injection passage 37 and the second injection passage 52. The plug portion 55 is formed into a cylindrical shape having the same diameter as the mounting groove 46 and, by plugging into the mounting groove 46, the adhesive passage 58 and each of the injection passages 37 and 52 are brought into fluid flow communication with each other. The large-diameter screwed engagement portion 56 is formed into a cylindrical shape which is larger in diameter than the plug portion 55 and is screwed with a male thread on the outer periphery thereof and, at the same time, a pair of spanner engaging portions 59 which are ground flat are formed. An outer periphery of the small-diameter screwed engagement portion 57 is also provided with a male so as to be engaged in a screwed manner with the injector main body 15. The inner diameter of the joint member 29 which serves as the adhesive passage 58 is configured to be larger than the diameter of the restriction portion 36 of the nozzle inner cylinder 25 and the slip-prevention portion 51 of the nozzle outer cylinder 40.

The fastening member 30 is formed into a

cylindrical shape with a metallic material such as stainless steel, steel, or the like, and is made up of: a large-diameter fastening portion 65 which is the largest in diameter in the injection nozzle 16; and a small-diameter fastening portion 66 which is formed on the front-end side and in communication with the large- diameter fastening portion 65. The inner diameter of the large-diameter fastening portion 65 is formed in the same diameter as the large-diameter portion 45 of the sealing member 41 and is provided with a female thread on the inner peripheral surface on the base end side thereof. The small-diameter fastening portion 66 is formed so as to cover the cylindrical portion 44 of the sealing member 41 and its inner diameter is formed in the same diameter as the cylindrical portion 44 of the sealing member 41. Then, an inner stepped portion between the large-diameter fastening portion 56 and the small-diameter fastening portion 57 is engaged with the outer stepped portion between the cylindrical portion 44 and the large-diameter cylindrical portion 45 of the sealing member 41. The fastening member 30 holds the nozzle main body 27 together with the joint member 29.

As a result, when the plug portion 55 of the joint member 29 is plugged into the mounting groove 46 of the nozzle main body 27, and the fastening member 30 is covered on the top ^' from the front-end side so that

the male thread of the large-diameter screwed engagement portion 56 and the female thread of the small-diameter fastening engagement portion 66 are engaged in a screwed manner with each other, the mounting groove 46 and the plug portion 55 are brought into close contact with each other, whereby the adhesive passage 58 and each of the injection passages 37, 52 are connected together. When the adhesive R flows from the injector main body 15 into the adhesive passage 58 of the joint member 29, the adhesive R is divided into the one which flows from the restriction portion 36 of the nozzle inner cylinder 25 into the first injection passage 37 and the other which flows from the slip-prevention portion 51 of the nozzle outer cylinder 40 into the second flow passage 52, and is discharged out of the discharge port 35 and the leak port 50, respectively. Since the nozzle inner cylinder 25 is formed to have the above-described length, it does not block the slip-prevention portion 51 of the nozzle outer cylinder 40.

Next, with reference to Fig. 4, a description will be made about an anchor pin 70. The anchor pin 70 is made of stainless steel, or the like and comprises: a disk-shaped pin head 71 which is formed to have a small thickness (0.3 mm to 0.5 mm) larger than the opening portion of the charging hole 8; and a bar-

shaped pin body portion 72 which is formed integrally with the pin head portion 71. When the anchor pin 70 is charged into the charging hole 8, the pin head portion 71 comes into abutment with the opening portion of the charging hole 8 and the pin body portion 72 reaches the innermost portion of the charging hole 8.

In order to increase the pull-resistance strength, the pin body portion 72 is provided with a male thread on the outer peripheral surface and is formed slightly smaller in diameter than the diameter of the charging hole 8. The top surface, i.e., the upper surface of the pin head portion 71 is decorated with a color by baking, or the like so ^' as to harmonize with the color of the finishing material 4. When the anchor pin 70 is charged into the charging hole 8, the pin body portion 72 anchors the concrete framework 2, the mortar 3, and the finish material 4 through the adhesive R. The pin head portion 71 thus blocks the opening portion of the charging hole 8 and also protrudes beyond the surface of the finishing material 4 by the amount equal to the thickness thereof. The pin head portion 71 is thus not flush with the finishing material 4 but, since it is formed to have a thin thickness, it hardly hits the eyes of an observer. In other words, the anchor pin 70 prevents the adhesive R from leaking out of the

charging hole 8, and the adhesive R solidifies in this state. The pin body portion 72 is thus firmly adhered to the charging hole 8.

With reference to the procedural diagrams in Figs . 5A to 5C to Figs. 7A to 7C, a description will be made about the pinning method, in the order of steps, for performing repairs of the outer wall 1 by using the above-described adhesive injector 10. This pinning method is made up of: a step of hammering the outer wall with a hammer to determine the boring position

(separated portion) for boring the charging hole 8; a step of boring the charging hole 8 through the outer wall 1 at the boring position; a step of injecting the adhesive R into the charging hole 8 by using the adhesive injector 10; and a step of charging the anchor pin 70 into the charging hole 8 into which the adhesive R has already been injected.

In the hammering step, the outer wall 1 is hammered with a hammer, or the like and, based on the hammering sound to detect that portion of the outer wall 1 which requires repairing, i.e., the first separated portion 6 between the concrete framework 2 and the mortar 3 and the second separated portion 7 between the mortar 3 and the finishing material 4, thereby determining the position of boring the charging hole 8. Subsequently, the boring position is

adequately marked up.

In the boring step, by using a boring tool 75 such as a diamond core drill, or the like, boring is made at each of the boring positions of the outer wall 1. In other words, the concrete framework 2 is bored to the predetermine depth by penetrating through the finishing material 4 and the mortar 3 to thereby form the charging holes 8. At this time, the boring is made at right angles to the outer wall 1, and the boring depth into the concrete framework 2 shall be greater than or equal to 30 mm. In addition, the charging hole 8 shall be formed slightly larger (by 1 mm to 2 mm) in diameter so that the anchor pin 70 can be loosely fit thereinto. Thereaftr, since the boring debris, or the like, of the concrete framework 2 remain in the charging hole 8, they are blown out with a blower or sucked with a vacuum cleaner, or the like, thereby- cleaning the charging hole 8. This cleaning step, however, is omitted in case the debris are driven out with cooling water.

In the adhesive injection step, the injecting nozzle 16 is inserted into the charging hole 8 until the inserting depth is restricted by the abutment of the nozzle main body 27 with the tapered portion 43, whereby the opening portion of the charging hole 8 is sealed with the tapered portion 43. In this state, the

discharge port 35 of the nozzle inner cylinder 25 has not reached the innermost portion of the charging hole 8. While urging the opening portion of the charging hole 8 with the tapered portion 43 in this state, the lever 20 of the injector main body 15 is operated (pumped) to thereby inject the adhesive R into the charging hole 8.

Once the pumping is started, the nozzle inner cylinder 25 advances toward the innermost portion relative to the nozzle main body 27. When the front end portion of the nozzle inner cylinder 25 has come into abutment with the innermost portion of the charging hole 8, the adhesive R is discharged from the discharge port 35 so as to be gradually injected from the innermost portion of the charging hole 8. The adhesive R soon flows into the first separated portion 6 between the concrete framework 2 and the mortar 3 and, at substantially the same time, the adhesive R is discharged also out of the leak port 50 so as to flow into the second separated portion 7 between the mortar 3 and the finishing material 4. At this time, air pocket will be formed in an intermediate portion of the charging hole between the mortar 3 and the finishing material 4. The air therein will however be vented by the negative pressure at the time of pulling out the injection nozzle 16 from the charging hole 8.

In the pin charging step, the anchor pin 70 is charged into the charging hole 8 which has been filled with the adhesive R, while the pin body portion 72 thereof is guided. The anchor pin 70 is charged into the innermost portion in such a manner as to push the adhesive R inside the charging hole 8. As a result of this operation, the adhesive R flows into the clearance so as to be spread over the pin body portion 72. Part of the adhesive R is further pushed toward the opening portion of the charging hole 8. Once the pin body portion 72 of the anchor pin 70 has reached the innermost portion, .the pin head portion 71 closes the opening portion of the charging hole 8. In this case, in the step of injecting the adhesive, it is so arranged that the volume of the adhesive non-injected portion which occurs after the nozzle inner cylinder 25 has been pulled out becomes substantially the same as that of the anchor pin 70. Therefore, when the anchor pin is inserted into the charging hole 8, the adhesive R will not leak, if any, out of the charging hole 8, whereby the charging hole 8 can be filled with the adhesive R almost to the full. By curing in this state, the anchor pin 70 serves to anchor with sufficient pull-resistance strength the concrete framework 2 and the mortar 3, as well as the mortar.3 and the finishing material 4.

As described hereinabove, according to the injection nozzle 16 of this embodiment, the adhesive R can be injected from the innermost portion of the discharge port 35 which is in communication with the first injection passage 37, and from the near side of the charging hole 8 through the leak port 50 which is in communication with the second injection passage 52. Therefore, the adhesive R can sufficiently be injected into the "separated portions" which have occurred between the concrete framework 2 and the mortar 3, as well as between the mortar 3 and the finishing material 4 (the adhesive will spread substantially into a circular shape about the charging hole 8) . As a result, the anchor pin 70 and the adhesive R can efficiently be acted upon the outer wall 1, whereby a complete repairing can be performed on the outer wall 1 in which "separated portions" have occurred.

Next, with reference to Fig. 7B, a description will now be made about a modified example of the anchor pin in the pinning method of the first embodiment.

This anchor pin 80 is made of stainless steel, or the like and is integrally made up of a pin body portion 82, and a pin head portion 81 which serves to hold the finishing material 4 in position. Further, in order to increase the pull-resistance strength, a male thread is formed on the peripheral surface of the pin body

portion 82. The pin head portion 81 is formed into a countersunk shape and, as in the first embodiment, is formed to have a diameter slightly larger than that of the opening portion of the charging hole 8. In other words, the pin head portion 81 has a mode similar to the head portion of the countersunk screw, or the like (but without a groove for engaging the tool) so as to have a sufficient strength. Further, the top surface of the pin head portion 81 is, as in the first embodiment, colored by baking, or the like so as to harmonize with the tint of the surface of the finishing material 4.

A description will now be made about the pinning method in case the above-described anchor pin 80 is used. It is to be noted that, in the following description, only what is different from the first embodiment is mainly described. In the same manner as in the first embodiment, a charging hole 8 is first drilled with a drilling tool 75 such as a diamond core drill, or the like, to a predetermined depth into the concrete framework 2 through the finishing material 4 and the mortar 3. Then, the opening edge portion of the charging hole 8 is chamfered to have the countersunk shape to correspond to the shape of the pin head portion 81 of the anchor pin 80. Once chamfering has been finished, the charging hole 8 is cleaned

inside. Then, the adhesive R is injected into the charging hole 8. Once the adhesive R has spread over the first separated portion 6 and the second separated portion 7, the anchor pin 80 is charged into the charging hole 8. At this time, the anchor pin 80 is forcibly pushed into the charging hole 8 such that the pin head portion 81 of the anchor pin 80 comes into contact with the opening edge portion of the charging hole 8, i.e., such that the surface of the pin head portion 81 of the anchor pin 80 becomes flush with that of the finishing material 4. Thereafter, curing is made until the adhesive R hardens.

According to this configuration, since the pin head portion 81 of the anchor pin 80 becomes flush with the surface of the finishing material 4 and since the pin head portion 81 of the anchor pin 80 is colored to suit the finishing material 4, the anchor pin 80 hardly strikes the eyes of the observer after having finished the repairing, whereby the design of the finishing material 4 is not impaired.

A description will now be made about a second modified example of the anchor pin. As shown in Fig. 1C, this anchor pin 90 is made of stainless steel, or the like and is integrally formed of a pin body portion 92, and a pin head portion 91 for holding the finishing material 4 in position. Further, in order to increase

the pull-resistance strength, a male thread is formed on the outer periphery of the pin body portion 92. The pin head portion 91 is formed into a circular shape in cross section and, similar to the first embodiment, is formed slightly larger in diameter than the diameter of the opening portion of the charging hole 8. The top surface of the pin head portion 81 is, as in the first embodiment, colored by baking, or the like so as to harmonize with the tint of the surface of the finishing material 4.

A description will now be made about the pinning method in case the above-described anchor pin 90 is used. A charging hole 8 is first drilled with a drilling tool 75 such as a diamond core drill, or the like, to a predetermined depth into the concrete framework 2 through the finishing material 4 and the mortar 3. In this case, a tool which has mounted an auxiliary bit at a base portion of the diamond core drill is used to thereby form simultaneously the charging hole 8 and a countersunk bore 94 which is larger in diameter than the charging hole 8. Thereafter, the charging hole 8 is cleaned inside and subsequently the injection nozzle 16 is inserted into the charging hole 8. The tapered portion 43 is urged against the countersunk bore 94 and the adhesive R is injected into the charging hole 8. Once the adhesive R

has spread over the first separated portion 6 and the second separated portion 7, the anchor pin 90 is charged into the charging hole 8. At this time, the anchor pin 80 is forcibly pushed into the charging hole 8 such that the pin head portion 91 of the anchor pin 90 comes into contact with the countersunk bore 94, i.e., such that the surface of the pin head portion 91 of the anchor pin 90 becomes flush with the surface of the finishing material 4. Thereafter, curing is made until the adhesive R hardens.

According to this configuration, since the pin head portion 91 of the anchor pin 90 becomes flush with the surface of the finishing material 4 and since the pin head portion 91 of the anchor pin 90 is colored to suit the finishing material 4, the anchor pin 90 hardly strikes the eyes of the ^' observer after having finished the repairing, whereby the design of the finishing material 4 is not impaired.

With reference to Fig. 8, a description will now be made about another embodiment of the injection nozzle of the adhesive injector 10 of this embodiment. The injection nozzle 100 of the second embodiment is made up of: a small-diameter nozzle inner cylinder 102 having a discharge port 101; a nozzle main body 103 which holds the nozzle inner cylinder 102 at the front end side so as to be movable back and forth; a joint

portion 104 for detachably mounting the nozzle main body 103 on the injector main body 15; and a fastening member 105 for fixedly attaching the nozzle main body 103 to the joint portion 104. A description is omitted because the injection nozzle 100 herein is similar in construction to the above described ones. This nozzle main body 103 is made of fluororubber and of a construction in which the nozzle outer cylinder 40 of the first embodiment is removed. In this case, the nozzle inner cylinder 102 is loosely fitted into the through hole 107 of a sealing member 106 so that a second injection passage 108 is formed by the clearance between the nozzle inner cylinder 102 and the through hole 107. The through hole 107 in this case is formed to have substantially the same inner diameter as the inner diameter of the nozzle outer cylinder 40 of the first embodiment. The portion forming this through hole 107 constitutes the "inner cylinder holding portion" in claims. When the nozzle main body 103 is urged against the opening portion of the charging hole 8 by using this injection nozzle 100, the outer peripheral surface of the tapered portion 109 of the nozzle main body 103 is brought into close contact therewith. Also, the fluororubber is adequately deformed to thereby seal the opening portion and, at the same time, a leak port 110

lies at a position in front of the second separated portion 7. At this time, since the fluororubber is solvent-resistant and is hard, it only slightly deforms under a pressing force by an operator, but will not block the second injection passage 108. Therefore, in the similar manner as in the above-described injection nozzle 16, the adhesive R will be spread over the first separated portion 6 and the second separated portion 7. Further, according to this configuration, the parts can be reduced in number, thereby attaining a simpler constitution .

It is, of course, possible to appropriately change the diameter (inner diameter and outer diameter) of the nozzle inner cylinder 25 and 102 constituting the first injection passage 37, and the dimensions of clearance between the nozzle inner cylinder 25 and 102 and the nozzle outer cylinder 40 or the through hole 107 constituting the second injection passage 5.