JP2001323462A - Fastening device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fastening device for preventing loosening of a fastened part by imparting a certain tensile force to a reinforcing member at all times which is located at the end (head) of the reinforcing member such as an anchor or a tie-rod and, if, for example, the reinforcing member is elongated or if a load imparting plate is moved downward to form a clearance between it and a fastened part, by following the elongation of the reinforcing member and automatically eliminating the clearance. SOLUTION: A cylindrical ball nut 7 is rotatably and thereadably engaged with the periphery of a ball screw portion 5 provided on a portion B of the anchor A, and a spring receiving seat 11 is axially movably disposed around the ball screw portion 5 via an annular bearing 10 at one end of the ball nut 7. An external thread 6 is provided at one end portion of the anchor A and a nut 14 is threadably attached thereto. Another spring receiving seat 12 corresponding to the spring receiving seat 11 is disposed below the nut 14 and a compression spring 13 is compressed between the two spring receiving seats 11 and 12 to energize the ball nut 7 toward the other end of the anchor A. The load imparting plate 2 is disposed at the other end of the ball nut 7 in such a manner as to be axially movable around the anchor A via the annular bearing 9.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for securing an end (head) of a ground anchor (hereinafter also referred to as an earth anchor) which has been driven into the ground, and a rolling method for compacting the ground such as an embankment layer. A fastening device at the end of the anchor to maintain tension on the anchor with the force applied,
Ends of reinforcements (including wires such as wires) such as anchors and tie rods used as load applying devices for applying a constant load to tie rods to connect the connection points while maintaining a predetermined connection force The present invention relates to a fastening device provided on the (head).

[0002]

2. Description of the Related Art The above-mentioned device for locking the head of an earth anchor has a structure in which a double nut is screwed into a male screw portion provided on the head of the earth anchor so that the two nuts are not loosened from each other. (Anchor bolts, foundation bolts) are common. There is also a structure in which a spring material is interposed under a nut screwed to the head of the anchor to apply a constant rolling force in a tightened state.

[0003] In addition, as shown in FIG. 9, if there is a portion of the reinforcing member 51 such as an anchor or a tie rod projecting to the ground, a) a structure in which a threaded plate 53 is applied to the projecting portion 52 and tightened with a nut 54. B) a structure in which the head of a reinforcing material such as an anchor is bent into an L-shape to be embedded in a protective work provided on a slope, a ground which is fragile with a grout anchor body (hereinafter referred to as an anchor) formed by grout 60, and the like When reinforcing the anchor, the anchor head 5 protruding on the ground surface
After carefully tightening the fastening nut 54 screwed to the threaded portion of the anchor head 52 in order to carefully perform the anticorrosion of Step 2, c) cover the entire head with a cap 55 as shown in FIG. The sealing material 56 is filled in the cap 55 to prevent humus, or d) the entire head is covered with the cap 55 as shown in FIG.
7 and the anchor portion on the opposite side of the backing plate 53 is also covered with a steel duct 58 and a seal 59 to prevent rust-preventive oil 5
There is a structure for preventing humus by filling with 7, for example, and by applying these structures, it is possible to maintain the tensile force of the reinforcing member 51 such as an anchor or a tie rod for a long period of time.

[0004]

However, there is room for improvement in the following points in the above-mentioned conventional fastening device. That is, for example, a thin multi-layered embankment layer horizontally stacked on a high-rigidity foundation (including a foundation such as a bedrock) described in Japanese Patent No. 2597116 is flattened between each embankment layer. Intermediate or grid-like reinforcements are interposed and laminated, and a high-rigid floor slab is installed on the uppermost embankment layer, and the high-rigid floor slab and a plurality of anchors vertically penetrating each reinforcement are attached. The foundation is constructed by connecting the floor slab and the foundation, applying compressive force to the entire embankment layer via the anchors, and integrating the embankment layers and reinforcing materials from the high-rigidity slab to the foundation. There is a body.

[0005] A high rigid floor slab is formed on the uppermost embankment layer of the foundation structure, and the lower ends of a plurality of anchors are vertically penetrated through the high rigid floor slab and each reinforcing material. Each anchor is fixed to the support, and the anchors are screwed to the thread of the anchor head via a high-rigid floor slab. In such a case, the thickness of the entire layer may be reduced due to a part of the embankment layer being degraded, a compression phenomenon over the entire layer, a seismic motion, or the like. In such a case, a gap is formed between the nut and the floor slab, and the tension applied to the anchor disappears. And if this state continues for a long time,
There is a risk that some of the foundation structures will collapse.

[0006] Iron reinforcing materials used for anchors, tie rods, anchor bolts, etc. (wires (wires)
), The reinforcing material (wire) may elongate, or the fastening part of the head may loosen. A gap is formed below the nut screwing portion of the portion, and the tension applied to the reinforcing member disappears. Then, loosening of the nut may occur, or in the case of an anchor bolt for installation of a machine, the installation location may be loosened and the power machine or the like may vibrate.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has an end (head) of a reinforcing material such as an anchor or a tie rod.
For example, when the reinforcing material is elongated or the load applying plate moves downward to create a gap between the fastening portion and the reinforcing member, the gap is automatically eliminated following the extension of the reinforcing material. It is an object of the present invention to provide a fastening device which can always apply a constant tension to a reinforcing material and prevent loosening of a fastening portion.

[0008]

In order to achieve the above object, a fastening device according to the present invention applies a tension to a reinforcing material such as an anchor or a tie rod, or applies a reinforcing material to a ground such as an embankment. It is a fastening device provided at the end of the reinforcing material used to apply a rolling force or the like, wherein a nut screwed to a male screw portion when an axial force acts on the reinforcing material. 1st thread angle set to rotate
An external thread portion is provided on a part of the reinforcing member, a cylindrical nut is rotatably screwed around the first external thread, and an annular bearing is provided around one end of the cylindrical nut around the first external thread portion. A spring receiving seat is provided movably in the axial direction, a second male screw portion is provided at one end of the reinforcing member, and a tightening nut is screwed into the spring receiving seat. Another spring receiving seat corresponding to the spring receiving seat is provided. Is disposed under the tightening nut, and a compression spring or an elastic body is compressed between the two spring receiving seats to urge the cylindrical nut toward the other end of the reinforcing member. On the other end side, a load applying plate is arranged via an annular bearing so as to be movable in the axial direction around the reinforcing member. In the present invention and claim 2, in the case of the ball screw portion and the ball nut, the thread angle of the first male screw portion is such that when a ball member is subjected to an axial force when a reinforcing material, that is, a ball screw portion is subjected to an axial force. It is set to an angle that can be rotated, that is, converted to a force in the direction of rotation, and is specifically described in claim 6.

According to the fastening device of the present invention having the above-described structure, the reaction force such as the tension and the rolling force applied to the reinforcing member acts on the load applying plate, and the tension applied to the reinforcing member. When the force or the rolling force changes, the reaction force acting on the load applying plate changes. As a result, the load applying plate tends to move in the axial direction with respect to the reinforcing material. When this direction is the biasing direction of the compression spring or the elastic body, the load applying plate is lowered with respect to the reinforcing material, so that the compression spring or the elastic body is extended, and the cylindrical nut is directed downward of the compression spring or the elastic body. Receive the urging force. Therefore, while the cylindrical nut rotates along the first male screw portion, it descends following the lowering of the load applying plate, and applies a downward rolling force to the load applying plate. For this reason, as the load applying plate is lowered, the lower spring receiving seat, the upper annular bearing, the cylindrical nut, and the lower annular bearing are simultaneously lowered, so that between the tightening nut at the upper end and the load applying plate. There is no gap, and the tension applied to the reinforcement is prevented from disappearing.

On the other hand, if the direction in which the load applying plate attempts to move is the direction against the compression spring or the elastic body, the load applying plate rises with respect to the reinforcing material, and at the same time, the compression spring or the elastic body compresses. As a result, the cylindrical nut rotates in the opposite direction along the first male screw portion, and rises as the load applying plate rises. Therefore, the load applying plate rises with respect to the reinforcing material, and the lower annular bearing, the cylindrical nut, the upper annular bearing, and the lower spring receiving seat simultaneously rise, and the compression spring or the elastic body is compressed. Therefore, as in the case described above, no gap is formed between the tightening nut at the upper end and the load applying plate, so that the tension applied to the reinforcing member is prevented from disappearing. As a result, for example, ground such as embankment is prevented from collapsing due to loss of the tension of the reinforcing material.

Further, the degree of loosening of the fastening portion can be easily determined based on the rotation angle and axial position of the cylindrical nut or the degree of extension of the compression spring or elastic body. A state such as expansion of the construct can be estimated. Further, when the compression spring or the elastic body is extended beyond a specified value, the tightening nut can be tightened to re-tension.

According to a second aspect of the present invention, there is provided a fastening device for applying a tension to a reinforcing member such as an anchor or a tie rod,
A fastening device provided at an end of the reinforcing material used for applying a rolling force to a ground such as an embankment via a reinforcing material, and a second device is provided along an axial direction from one end of the reinforcing material. An external thread portion, a spline portion or a key groove portion and a first external thread portion are provided in this order, a tightening nut is screwed onto the second external thread portion, and a spring receiving seat is provided under the tightening nut around the second external thread portion. A non-rotatable spring seat is provided around the spline or key groove on the inner peripheral side of the spline or key groove. The first male screw portion has a thread angle set such that a nut screwed to the male screw portion rotates when an axial force acts on the reinforcing member, 1 A cylindrical nut is rotatably screwed around the male screw, and the cylindrical nut is An engagement mechanism is provided between the inner ring and the outer ring, between the inner ring and the non-rotating spring receiving seat, around the spline portion, the keyway portion, or the first male screw portion, the inner ring being allowed to rotate in one direction relative to the outer ring. A rotatable one-way rotating mechanism, an annular bearing is interposed between the inner ring and the non-rotating spring receiving seat, and the outer ring is integrally connected to the non-rotating spring receiving seat. Is connected to the cylindrical nut so as to be integrally rotatable, a compression spring or an elastic body is compressed between the spring receiving seats to urge the non-rotating spring receiving seat toward the other end of the reinforcing member, and the cylindrical On the other end side of the nut, a load applying plate is provided via an annular bearing so as to be movable in the axial direction around the reinforcing member.

According to the fastening device of the second aspect having the above-described structure, the tension, the rolling force, and the like applied to the reinforcing member are changed similarly to the fastening device of the first aspect, and the load applying plate is provided. The reaction force acting on the reinforcing member changes, and the load applying plate tends to move in the axial direction with respect to the reinforcing member. When this direction is the biasing direction of the compression spring or the elastic body, the cylindrical nut is formed as the spline sleeve or the load applying plate descends with respect to the reinforcing material under the biasing force of the compression coil spring or the elastic body. Descends while rotating clockwise, as a result, the load applying plate descends with the amount of contraction of the foundation structure, and the lower spring seat, ball bearing, spline sleeve,
Since the cam clutch, the cylindrical nut, and the ball bearing descend at the same time, there is no gap between each member between the tightening nut at the upper end and the load applying plate, and the tension applied to the reinforcing member is reduced. Since their disappearance is prevented, the collapse of the substructure is reliably prevented.

On the other hand, the reaction force acting on the load applying plate changes, and the direction in which the load applying plate moves in one of the axial directions with respect to the reinforcing material is the direction against the urging force of the compression spring or the elastic body. In some cases, the load applying plate tends to rise against the reinforcement, so the cylindrical nut tries to rotate counterclockwise, and the inner ring also tries to rotate counterclockwise with the cylindrical nut. The rotation in the clockwise direction is regulated via the one-way clutch by the outer ring which is integrally connected to the spline sleeve and held in a non-rotational state, so that the cylindrical nut does not rotate in the counterclockwise direction. For this reason, since the cylindrical nut cannot be lifted, the load applying plate does not rise with respect to the reinforcing material. As a result, the expansion of the foundation structure is suppressed by the load imparting plate held at the fixed position of the reinforcement, so that the tension acting on the reinforcement increases, and the foundation structure has an increased rolling force of the reinforcement. Will receive. In other words, according to the fastening device of the second aspect, with respect to the contraction phenomenon of the foundation structure, the load-applying plate descends and follows so that the tension of the reinforcing material is not loosened. Acts to suppress the expansion phenomenon.

Further, the degree of loosening of the fastening portion can be easily determined from the rotation angle and axial position of the cylindrical nut or the degree of extension of the compression spring or elastic body. A state such as expansion of the construct can be estimated. Further, when the compression spring or the elastic body is extended beyond a specified value, the tightening nut can be tightened to re-tension.

Preferably, the first male screw portion is a ball screw portion, and the cylindrical nut is a cylindrical ball nut.

According to the third aspect of the present invention, since the ball screw portion and the ball nut screwed to the ball screw portion are used, the frictional resistance becomes very small.
Even if it is reduced to about °, the ball nut rotates reliably when an axial force acts on the reinforcing material. In the fastening device of the present invention, the frictional resistance of the first male screw portion is small, and the smaller the thread angle, the more reliably the cylindrical nut rotates. Therefore, by using this configuration, the axial force is applied to the reinforcing member. When actuated, the cylindrical ball nut rotates smoothly and reliably.

According to a fourth aspect of the present invention, a ball spline sleeve is provided, wherein the ball spline portion is used as the spline portion, and the ball spline sleeve is mounted on the non-rotating spring seat so as to be movable in the axial direction around the ball spline. It is desirable to use a spring seat that is integrally connected to the sleeve.

According to the fourth aspect of the present invention, the ball spline sleeve smoothly moves in the axial direction along the ball spline portion, and the rotation of the ball spline sleeve is integrated with the spring receiving seat. Is prevented by the engagement relationship with

The one-way rotating mechanism may further include a one-way rotating mechanism as the engaging mechanism, wherein the one-way rotating mechanism includes an engaging mechanism interposed between the inner and outer wheels for allowing rotation of the inner ring in only one direction with respect to the outer ring. A cam clutch with a clutch can be used.

According to the fastening device of the fifth aspect, the height in the axial direction can be suppressed, and the height of the entire device can be suppressed low, and the size can be reduced.

Preferably, the thread angle of the ball screw portion is set within a range of 5 ° to 30 °.

According to the sixth aspect of the present invention, since the thread angle of the ball screw portion is set to 5 ° or more and 30 ° or less, when the axial force acts on the reinforcing member, the ball nut can be almost certainly fixed. It is converted into the force to rotate. The larger the thread angle (gradient) of the ball screw is,
The ball nut is reliably converted to rotational energy,
Conversely, if it is too large, the rotation angle of the ball nut may become excessive and rotation may not stop.
It must be set within 0 °.

[0024]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a fastening device according to the present invention will be described below with reference to the drawings.

FIG. 1 is a central longitudinal sectional view showing an embodiment of the fastening device of the present invention, and FIG. 2 is an overall perspective view showing the appearance of the fastening device of FIG.

As shown in FIGS. 1 and 2, the fastening device 1 of this embodiment is provided on an anchor (reinforcing material) A, and the anchor A is a foundation construction by embankment of the above-mentioned Japanese Patent No. 2597116. The fastening device 1 is provided above each anchor A.

As shown in FIG. 6, this basic construct y
A thin, multiple embankment layer 52 stacked horizontally on a high-rigidity foundation (including a foundation such as a bedrock) 51 is provided with a flat net-like or lattice-like reinforcing material 53 interposed between the embankment layers 52. A high-rigid floor slab (load applying slab) 54 (2) is installed on the uppermost embankment layer 52, and a plurality of anchors A vertically penetrate the floor slab 54 and the reinforcing members 53. Connect the plate 54 and the foundation 51 and fix their anchors A
, A compressive force is applied to the entire embankment layer 52, and each embankment layer 52 and the reinforcing material 53 from the highly rigid floor slab 54 to the foundation.
Are integrated.

In FIG. 1 and FIG. 2, two coil springs 4 at the lower part of the main body of the anchor A are sandwiched from above and below.
Of the two flat plates 2, 3, the upper flat plate 2 corresponds to the floor slab 54 serving as the load applying plate, and the lower flat plate 3 corresponds to the base 51 in the basic construction y. Also, the upper and lower flat plates 2.
The portion of the coil spring 4 sandwiched between 3 is the foundation structure y
And the reaction force from the foundation structure y always acts on the upper flat plate 2.

On the upper portion (head) B of the anchor A, a large-diameter first male screw portion (ball screw portion) 5 and a small-diameter second male screw portion 6 are formed in this order from the bottom to the top. The large-diameter ball screw portion 5 is considerably longer than the small-diameter male screw portion 6. A cylindrical ball nut 7 having upper and lower ends opened is rotatably screwed around the ball screw portion 5, and a ball groove 7a formed on the inner peripheral surface of the ball nut 7 and the like as shown in FIG. Thread groove 5a of ball screw part 5
Between them, a large number of balls 8 are continuously arranged in series, and grease (not shown) is loaded. The ball nut 7 includes a cylindrical main body 7A, an upper annular cover body 7B, and a lower annular cover body 7C. With the balls 8 loaded in the main body 7A, the upper annular cover body 7B and the lower annular cover body 7C The main body 7A is integrally fixed to the upper surface or the lower surface, respectively. A single type thrust ball bearing 9 is interposed between the lower annular cover 7C and the upper flat plate 2. Although the details of the configuration of the ball screw portion 5 will be described later, the thread angle θ, that is, the lead l (pitch p) is larger than that of the general male screw portion 6 and the like.

Around the vicinity of the upper end of the ball screw portion 5,
A spring receiving seat 11 having an inner diameter slightly larger than the outer shape of the ball screw portion 5 is loosely inserted slidably in the axial direction (vertical direction), and a single type thrust ball bearing 10 is provided between the upper surfaces of the ball nuts 7.
Is interposed. A spring seat 12 having an inner diameter slightly larger than the outer shape of the male screw portion 6 is loosely inserted around the upper portion of the upper male screw portion 6 so as to be slidable in the axial direction (vertical direction). A compression coil spring 13 is compressed around the ball screw portion 5 and the male screw portion 6 between the upper and lower spring receiving seats 11 and 12. A nut 14 for fastening is screwed to the upper end of the male screw portion 6 via a washer 14a, and tightened. Compression coil spring 13
Has a spring strength corresponding to the total spring strength of the four coil springs 4 as the foundation structure y (FIG. 6).

In the fastening device 1, the anchor A
The thread angle θ of the ball screw portion 5 required to rotate the ball nut 7 when an axial force acts on the ball screw 7 is determined by the frictional resistance between the ball screw portion 5 and the ball nut 7 and the diameter of the ball screw portion 5. Although a specific numerical value of the number of times or more is not specified because it changes due to the change of the thread angle θ, the thread angle θ (FIG. 5) is set so that the ball nut 7 rotates when an axial external force w acts on the anchor A. In this example, the angle is calculated based on the test result and set to about 18 °, but the present invention is not limited to this. The reason for using the ball screw portion 5 and the ball nut 7 is that the frictional resistance between the two is reduced as much as possible so that the thread angle θ of the ball screw portion 5 does not need to be set so large that the axial direction of the anchor A can be changed. This is to enable the ball nut 7 to rotate when an external force w acts. In addition, the code | symbol r in FIG. 5 represents the radius of the ball screw part 5, and p represents the pitch of a screw thread.

Next, an application example of the fastening device 1 according to the present embodiment configured as described above and an operation mode in the application example will be described.

As shown in FIG. 6, reference numeral 51 denotes a high-rigidity foundation (hereinafter, referred to as a concrete foundation) made of reinforced concrete, steel, or the like. The concrete foundation 51 has a predetermined thickness (generally, about 30 to 50 cm). Embankment layer 52
Are stacked, and a flat or substantially flat reinforcing member 53 having a large friction coefficient and a large tensile strength is interposed between the embankment layers 52. As the reinforcing material 53, a zinc-plated steel strip, a nonwoven fabric, or the like is used in addition to a polymer grid net or a metal net having excellent weather resistance. 5
Reference numeral 4 denotes a high-rigidity floor slab (hereinafter referred to as a concrete floor slab) made of reinforced concrete or steel formed on the uppermost embankment layer 52, and a plurality of anchors A through which the concrete floor slab 54 penetrates. The lower end z of each anchor A is fixed to the concrete foundation 51 by penetrating the embankment layer 52 and the reinforcing material 53 therebelow and inserting it to the lowermost concrete foundation 51. Then, the concrete floor slab 54 is pressed downward through the anchors A, and a compressive force is applied to the concrete foundation 51 and the embankment layer 52 sandwiched between the concrete floor slabs 54, whereby the concrete floor slab 54 is pressed.
Each embankment layer 52 and the reinforcing material 53 that further lead to the concrete foundation 51 are integrated to form a foundation construction y as a kind of pseudo skeleton.

The fastening device 1 of this embodiment is provided at the head (upper end) B of each anchor A. Then, the following effects are exhibited. That is, in FIG. 1 or FIG. 2, in the case of the above-mentioned foundation structure y, after the formation and compaction of the embankment layer 52 are completed, various types of the embankment layer 52 between the highly rigid floor slab 54 and the foundation ground 51 below Since the compressive force in consideration of the maximum value of the external force and the safety factor is given in advance by the tension of the anchor A, even if the above various external forces act on the embankment layer 52 after the structure of the foundation structure y, each embankment Layer 52 will exhibit integrated behavior. In other words, since a force corresponding to the maximum external force is previously given to the foundation structure y (the embankment layer 52) through the anchor A, the foundation structure y
Is almost completed when the anchor A is tensioned.

Here, the relationship between the forces in the embankment layer 52 after the completion of the formation and compaction will be described. In FIG. 6, the internal force of the embankment layer 52 is Ps, the tension of the anchor A is Pc, and the vertical external force is Pw. When the own weight of the foundation structure y is Wo and the reaction force of the foundation ground is Q, when the tension Pc is applied to the anchor A without applying the external force Pw, the internal force Ps of the embankment layer 52 becomes the tension of the anchor A. It increases in proportion to Pc. In addition, the reaction force Q of the foundation ground is the own weight Wo of the foundation construction y. In addition,
In FIG. 6, the symbol x indicates the head of the anchor A, y indicates the basic structure of the anchor A, and z indicates the anchoring portion of the anchor A.

As described above, since the compressive settlement of the foundation structure y is almost completed at the stage where the tension is applied to the anchor A, the possibility that the foundation structure y will undergo compression settlement is small.
Even if the foundation structure y is compressed or conversely expanded, the above-described fastening device 1 functions as follows.
That is, assuming that the base construct y is contracted and the overall thickness is reduced, this state corresponds to the state in which the four coil springs 4 are contracted in FIGS. Therefore, the upper flat plate 2 (concrete floor slab 54) is lowered with respect to the anchor A, but when the flat plate 2 is lowered, the upper compression coil spring 13 is extended, and the ball nut 7 is moved downward of the compression coil spring 13. Receive the urging force. Therefore, in the case of this example, the ball nut 7 rotates clockwise along the ball screw portion 5 while the flat plate 2 is rotated.
And descends to apply a downward rolling force to the flat plate 2. As a result, the flat plate 2 descends in accordance with the contraction amount of the foundation structure y, and the lower spring seat 1
1, since the ball bearing 10, the ball nut 7, and the ball bearing 9 descend at the same time, no gap is formed between the members between the nut 14 at the upper end and the flat plate 2, and the tension applied to the anchor A The loss of force is prevented. As a result, the collapse of the foundation structure y is reliably prevented.

Conversely, assuming that the foundation structure y has expanded and the overall thickness has increased, this state occurs in FIGS. 1 and 2 in which the four coil springs 4 are opposed to the upper compression coil springs 13. This corresponds to an extended state. Therefore, the compression coil spring 13 is compressed at the same time when the upper flat plate 2 (the concrete floor slab 54) rises with respect to the anchor A. However, when the flat plate 2 rises, the ball nut 7 becomes the four coil springs 4. Receive an upward bias by Therefore, in the case of this example, the ball nut 7 rises following the rise of the flat plate 2 while rotating counterclockwise along the ball screw portion 5. As a result, the flat plate 2 rises with the amount of expansion of the foundation structure y, the ball bearings 9, the ball nuts 7, the ball bearings 10, and the lower spring receiving seats 11 rise at the same time, and the compression coil springs 13 rise. Since it is compressed, no gap is formed between each member between the upper end nut 14 and the flat plate 2 as in the above case, and the tension applied to the anchor A is prevented from disappearing. . As a result, the collapse of the foundation structure y is reliably prevented.

Next, another embodiment of the fastening device according to the present invention will be described with reference to the drawings.

FIG. 3 is a central longitudinal sectional view showing another embodiment of the fastening device of the present invention, and FIG. 4 is an overall perspective view showing the appearance of the fastening device of FIG. As shown in FIGS. 3 and 4, the main difference between the fastening device 1 according to the second embodiment and the fastening device 1 according to the above-described first embodiment is that the foundation structure y shrinks and the overall thickness increases. Is reduced, the upper plate 2 becomes the anchor A
As the ball nut 7 descends, the ball nut 7 rotates downward while rotating clockwise.
, The rotation of the ball nut 7 in the counterclockwise direction is restricted, and the flat plate 2 is configured so as not to rise with respect to the anchor A.

That is, in this embodiment, the cylindrical portion 7D of the upper annular cover 7B of the ball nut body 7A is extended upward, and the key 7F is interposed in the key groove 7E provided in the extended cylindrical portion 7D. Inner ring (inner race) around cylindrical part 7D
21 are provided so as to be integrally rotatable and relatively movable in the axial direction. An outer race 22 is provided around the inner race 21, and a one-way clutch 23 (see FIG. 7) is provided between the inner race 21 and the outer race 22 as an engagement mechanism that allows rotation of the inner race 21 in one direction. That is, the inner ring 21, the outer ring 22, and the one-way clutch 23 form the cam clutch 20 as a one-way rotation mechanism. As shown in FIG. 8, a cam clutch 2 using a free-action cam clutch 25 instead of the one-way clutch 23 is used.
0 'may be used. In this example, each cam 25a is held by an annular holder 25b and connected by an annular spring 25c. In addition, although not shown, each cam 25
There is also a roller in which a roller is arranged between a.

The ball screw portion 5 is provided on the upper portion of the anchor A in the same manner as in the above embodiment. Immediately above the ball screw portion 5, a ball spline 15 is integrally connected to the upper end of the ball screw portion 5 by a cylindrical sleeve joint 16. I have. At the upper end of the ball spline 15, a small-diameter male screw portion 6 is integrally provided continuously. Around the ball spline 15, a spline sleeve 17 in which a ball (not shown) is interposed at a spline engagement portion (not shown) is provided so as to allow only movement in the axial direction. A non-rotating plate 18 having an inner diameter slightly larger than the outer diameter of the ball spline 15 is integrally connected to the lower surface of the spline sleeve 17. A collar 19, which is in contact with the upper end of the cylindrical portion 7D of the upper annular cover body 7B and has a slightly larger inner diameter than the outer shape of the ball spline 15, is disposed around the ball spline 15, and the collar 19 and the non-rotating plate 18 A single type thrust ball bearing 10 is interposed therebetween. Then, the two through holes 1 are formed in the non-rotating plate 18.
8a, and a lower end screw portion of a stop bolt 24 inserted downward into each through hole 18a is screwed to the outer ring 22 to support the outer ring 22 in a non-rotating state.

A spring seat 12 having an inner diameter slightly larger than the outer shape of the male screw portion 6 is formed around the upper portion of the male screw portion 6.
Are slidably inserted in the axial direction slidably, and a spring receiving seat 11 having an inner diameter slightly larger than the outer shape of the ball spline 15 is slidably inserted in the axial direction around the upper portion of the ball spline 15, Upper and lower spring seats 11 and 12
A compression coil spring 13 is contracted around the ball spline 15 between them. The nut 14 is screwed to the upper end of the male screw portion 6 via a washer 14a, and the spring receiving seat 12 is tightened. The compression coil spring 13 has a spring strength corresponding to the total spring strength of the four coil springs 4 of the foundation structure y (FIG. 6). Other configurations are the same as those of the above-described embodiment, and therefore, common members are denoted by common reference numerals, and description thereof is omitted.

According to the fastening device 1 according to the present embodiment, when the basic structure y is contracted and the overall thickness is reduced, similarly to the fastening device 1 of the first embodiment, the compression coil spring 13 is used. As the spline sleeve 17 and the upper flat plate 2 descend against the anchor A under the urging force, the ball nut 7 descends while rotating clockwise, and as a result,
Since the flat plate 2 descends with the contraction amount of the foundation structure y, the lower spring seat 11, the ball bearing 10, the spline sleeve 17, the cam clutch 20, the ball nut 7, and the ball bearing 9 descend at the same time. Since there is no gap between each member between the nut 14 at the upper end and the flat plate 2 and the tension applied to the anchor A is prevented from disappearing, the collapse of the foundation structure y is ensured. Is prevented.

On the other hand, the base structure y expands in the opposite
When the ball nut 7 is pushed up, the ball nut 7 is pushed up by the flat plate 2, so that the ball nut 7 tries to rotate in the counterclockwise direction and the inner ring 21 also tries to rotate with the ball nut 7. The rotation in the clockwise direction is regulated via the one-way clutch 23 with respect to the outer ring 22 which is integrally connected to the spline sleeve 17 and held in a non-rotation state.
Does not rotate counterclockwise, so the ball nut 7
Does not rise, the flat plate 2 does not rise with respect to the anchor A. As a result, since the expansion of the foundation structure y is suppressed by the flat plate 2, the tension acting on the anchor A increases, and the foundation structure y receives the increased rolling force from the anchor A. In other words, according to the fastening device 1 of the present example, the flat plate 2 descends correspondingly to the contraction phenomenon of the foundation structure y so that the tension of the anchor A does not loosen, but the foundation structure y Acts to suppress the expansion effect.

By the way, the above-mentioned common application 2
Although one embodiment is shown, the fastening device of the present invention can be applied to, for example, the following applications and can be carried out as follows.

Instead of the anchor A, it can be used as a locking device by applying to the upper part (head) of a tie rod, earth anchor, or the like. Especially the fastening device 1 according to the second embodiment
Acts so as to follow the relative elongation phenomenon of the anchor A and to prevent the anchor A from contracting, and acts to prevent the contraction phenomenon of the anchor A from contracting. The nut 14) is prevented from loosening.

When connecting between bridges or bridges on a highway, the connecting device is applied to one end of a joint portion and allows expansion and contraction of the joint portion based on thermal expansion and contraction due to a temperature (temperature) difference. Can be used.

The present invention can be used for fastening parts that are susceptible to vibrations due to seismic motion or for fastening parts of a machine foundation where vibrations are caused by repeated loads. Further, the necessity of retightening the tightening nut 14 can be easily determined from the degree of extension of the compression coil spring 13 and the like, and the nut 14 can be tightened to re-tension the reinforcing material A if necessary.

The dimensions of the fastening device according to the above two embodiments, especially the length, can be reduced and downsized according to the intended use, or can be extended to be longer.

The mechanism for allowing the movement of the ball nut 7 in only one direction shown in the fastening device 1 according to the second embodiment is not limited to the cam clutches 20 and 20 ′, but may be, for example, one direction along the axial direction. May be provided with a gear or a cam that can be meshed when moving.

Instead of the ball spline 15 and the spline sleeve 17, an ordinary spline mechanism without a ball is used, or the sleeve is provided with a key groove and a key (locking portion) for locking the key groove. A locking mechanism can be used.

Instead of the compression coil spring 13,
For example, an elastic body made of an air spring or a columnar rubber can be used. Instead of the ball screw 5 and the ball nut 7, a normal male screw portion and a cylindrical nut can be used. However, in this case, since the frictional resistance becomes considerably large, it is necessary to set the thread angle θ to be considerably large so that the cylindrical nut rotates when an axial force acts on the reinforcing material A. Further, in order to reduce the frictional resistance at the threaded portion, for example, a male screw having a surface coated with Teflon (registered trademark) on the surface of the external thread or a nut having a surface coated with Teflon on the internal screw (screw hole) can be used.

[0053]

As is apparent from the above description,
The fastening device according to the present invention has the following excellent effects.

(1) The invention according to claim 1 is provided at the end (head) of a reinforcing material such as an anchor or a tie rod, so that the structure is simple and the weight and size can be reduced. When the plate moves downward to create a gap with the fastening part, or when the reinforcing material shrinks or the load applying plate tries to move upward, the plate automatically follows the elongation or shrinkage of the reinforcing material. It is possible to eliminate the gap, and to always apply a constant tension to the reinforcing member to prevent the tightened portion from loosening. Therefore, there is no gap between the fastening portion of the head of the reinforcing member and the load applying plate, and the tension applied to the reinforcing member is prevented from disappearing. In addition, the degree of loosening of the fastening part can be easily determined based on the rotation angle and axial position of the cylindrical nut, or the degree of extension of the compression spring or elastic body. A state such as expansion can be estimated. Further, when the compression spring or the elastic body is extended beyond a specified value, the tightening nut can be tightened to re-tension.

(2) According to the second aspect of the present invention, when, for example, the foundation structure shrinks and the overall thickness decreases, as in the first aspect of the invention, the load applying plate is lowered with respect to the reinforcing material. The cylindrical nut descends while rotating clockwise, and there is no gap between the fastening portion of the head of the reinforcing member and the load applying plate, and the tension applied to the reinforcing member disappears. Conversely, even if the foundation structure expands and the load applying plate is pushed up against the reinforcement, the rotation of the cylindrical nut in the counterclockwise direction is restricted, and the load applying plate is positioned at the fixed position of the reinforcement. And the expansion of the foundation structure is suppressed, and no gap is formed between the fastening portion of the head of the reinforcing member and the load applying plate, and the loosening of the fastening portion is prevented. Claim 1
Similarly to the invention of the invention, the looseness of the fastening portion can be easily determined by the rotation angle and the axial position of the cylindrical nut or the degree of extension of the compression spring or the elastic body. The state such as expansion of the foundation structure can be estimated, and when the compression spring or the elastic body expands beyond a specified value, the tightening nut can be tightened to re-tension.

(3) According to the third aspect of the present invention, since the frictional resistance is very small, even when the thread angle is reduced to about 5 °, the ball nut is not affected when the axial force acts on the reinforcing member. Rotate reliably.

(4) According to the fourth aspect of the invention, the ball spline sleeve smoothly moves in the axial direction along the ball spline portion, and at the same time, the rotation of the ball spline sleeve is integrated with the spring receiving seat to rotate with the ball spline. Are prevented by the engagement relationship.

(5) According to the fifth aspect of the present invention, the height in the axial direction can be suppressed, and the height of the entire apparatus can be suppressed to be small, and the size can be reduced.

(6) In the invention according to claim 6, since the thread angle of the ball screw portion is set to 5 ° or more and 30 ° or less, when an axial force acts on the reinforcing member, the ball nut is almost certainly formed. Is converted into a force for rotating the ball nut, and there is no fear that the rotation angle of the ball nut becomes excessive and rotation does not stop.

[Brief description of the drawings]

FIG. 1 is a central longitudinal sectional view showing an embodiment of a fastening device of the present invention as a kind of model.

FIG. 2 is an overall perspective view showing the appearance of the fastening device of FIG.

FIG. 3 is a central longitudinal sectional view showing another embodiment of the fastening device of the present invention as a kind of model.

4 is an overall perspective view showing the appearance of the fastening device of FIG.

FIG. 5 is a central longitudinal sectional view showing an enlarged detail of a ball nut 7 in FIG. 1;

FIG. 6: Concrete foundation 5 from concrete floor slab 54
1 is a longitudinal sectional view schematically showing a state in which a fastening device 1 of the present invention is applied to a foundation structure y in which each embankment layer 52 and a reinforcing material 53 are integrated.

FIG. 7 is an enlarged view taken along the line II in FIG.
0 represents a detailed structure.

FIG. 8 is an enlarged view taken along the line II in FIG.
7 shows the detailed structure of another cam clutch 20 ′ instead of 0.

FIGS. 9A and 9B are cross-sectional views showing a conventional general humus preventing structure.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 fastening device 1 ′ device main body 2 flat plate (load applying plate) 3 flat plate 4 coil spring 5 ball screw portion (first male screw portion) 6 male screw portion (second male screw portion) 7 ball nut (cylindrical nut) 7 A main body 7 B・ 7C annular cover 7a ball groove 8 ball 9 ・ 10 single type thrust ball bearing (annular bearing) 11 ・ 12 spring seat 13 compression coil spring (or elastic body such as rubber) 14 fastening nut (tightening nut) 15 ball Spline 16 Cylindrical sleeve joint 17 Spline sleeve 18 Non-rotating plate 19 Collar 20/20 'cam clutch (one-way rotation mechanism) 21 Inner ring (inner race) 22 Outer ring (outer race) 23/25 One-way clutch (engagement mechanism) A Anchor (reinforcement material) Bx Upper part of anchor (head) y Foundation structure z Anchor fixing part

Claims (6)

[Claims] 1. A reinforcing member provided at an end portion of a reinforcing material used for applying a tension to a reinforcing material such as an anchor or a tie rod or applying a rolling force to a ground such as an embankment via a reinforcing material. A fastening device, comprising: a first male screw portion having a thread angle set such that a nut screwed into the male screw portion rotates when an axial force acts on the reinforcing member. And a cylindrical nut is rotatably screwed around the first male screw, and a spring seat is axially moved around the first male screw via one end of the cylindrical nut via an annular bearing. While freely arranging,
A second male screw portion is provided at one end of the reinforcing member, a tightening nut is screwed on, and another spring receiving seat corresponding to the spring receiving seat is provided below the tightening nut, and the two springs are provided. A compression spring or an elastic body is compressed between receiving seats to urge the cylindrical nut toward the other end of the reinforcing member, and the other end of the cylindrical nut is provided with a load applying plate via an annular bearing. A fastening device, wherein the fastening device is disposed so as to be movable in the axial direction around a reinforcing member. 2. A reinforcing member provided at an end portion of the reinforcing member used for applying a tension to a reinforcing member such as an anchor or a tie rod or applying a rolling force to a ground such as an embankment via the reinforcing member. A fastening device, wherein a second external thread portion is provided along an axial direction from one end of the reinforcing member,
A spline portion or a key groove portion and a first male screw portion are provided in this order, a tightening nut is screwed to the second male screw portion, and a spring receiving seat is axially provided around the second male screw portion under the tightening nut. It is movably arranged, and a non-rotatable spring receiving seat is provided around the spline portion or the key groove portion on the inner peripheral side. The locking portion is locked in the spline groove or the key groove so as to be movable in the axial direction. The first male screw portion has a thread angle set such that a nut screwed to the male screw portion rotates when an axial force is applied to the reinforcing member. A cylindrical nut is rotatably screwed around the inner ring around the spline portion or the key groove portion or the first male screw portion between the cylindrical nut and the non-rotating spring seat. An interlocking mechanism that allows only one direction between the inner and outer rings A rotatable one-way rotating mechanism, an annular bearing is interposed between the inner ring and the non-rotating spring receiving seat, and the outer ring is integrally connected to the non-rotating spring receiving seat. Is connected to the cylindrical nut so as to be integrally rotatable, and a compression spring or an elastic body is compressed between the spring receiving seats to urge the non-rotating spring receiving seat toward the other end of the reinforcing member, and the cylindrical A fastening device, wherein a load applying plate is disposed at the other end of the nut through an annular bearing so as to be axially movable around the reinforcing member. 3. The fastening device according to claim 1, wherein the first male screw portion is a ball screw portion, and the cylindrical nut is a cylindrical ball nut. 4. The ball spline portion is a ball spline portion, and the non-rotating spring seat is disposed around the ball spline so as to be movable in the axial direction, and is integrally connected to the sleeve. 3. The fastening device according to claim 2, wherein the fastening device comprises a spring seat. 5. The cam clutch having a one-way clutch as the engagement mechanism, wherein the one-way rotation mechanism having an engagement mechanism that allows rotation of the inner ring with respect to the outer ring in only one direction is interposed between the inner and outer rings. The fastening device according to claim 2. 6. The thread angle of the ball screw portion is 5 ° to 5 °.
The fastening device according to claim 3, wherein the fastening device is set in a range of 30 °.