CN212583057U

CN212583057U - But assembled stretch-draw reinforcing bar straight thread connection device

Info

Publication number: CN212583057U
Application number: CN202020824730.4U
Authority: CN
Inventors: 储宏道
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-05-18
Filing date: 2020-05-18
Publication date: 2021-02-23
Anticipated expiration: 2030-05-18

Abstract

The utility model provides a but assembled stretch-draw reinforcing bar straight thread connecting device, includes first swivel nut, second swivel nut and connecting sleeve. The internal threads of the first screw sleeve and the second screw sleeve are respectively used for being screwed with the external threads of the first steel bar screw head and the second steel bar screw head to form a first screw pair and a second screw pair, and the external threads of the first screw sleeve are screwed with the internal threads of the connecting sleeve to form a third screw pair; one end of the connecting sleeve is provided with a conical hole, and the diameter size of the conical hole is gradually reduced from inside to outside; one end of the outer side surface of the second screw sleeve is provided with a first conical surface, and the first conical surface is equal to and contacts with the conical hole of the connecting sleeve in conical degree. The utility model discloses can be at two reinforcing bars along radial and axial displacement, can not rotate, and under the condition that the helix of two reinforcing bar thread head threads has the deviation dislocation, realize the reliable connection between two reinforcing bars to apply prestressing force tension.

Description

But assembled stretch-draw reinforcing bar straight thread connection device

Technical Field

The utility model relates to a reinforcing bar is connected and is exerted prestressing force tension's device in assembly type building construction is applicable to between the assembled prefabricated component to and prefabricated component and cast-in-place and post-cast steel bar connection between the concrete structure, the assembled of specially adapted prestressed concrete component is connected, like pretension method or post-tensioning prestressing force component. The connecting device can be used in the building environment that the connected steel bar cannot move along the radial direction and the axial direction and cannot rotate, and the spiral line of the thread of the steel bar thread is deviated and dislocated.

Background

The industry standard "technical rules for prefabricated concrete structures" (JGJ 1-2014, hereinafter "rules") indicates that "the key to success or failure of the prefabricated structures lies in the connection technology between prefabricated components and between the prefabricated components and cast-in-place and post-cast concrete, wherein the connection technology comprises the selection of connection joints and the structural design of connection nodes, and the connection technology of the prefabricated components is the key and core technology of the prefabricated structures. Among them, the steel bar sleeve grouting joint technology is the main joint technology recommended by the regulation, and is also an important foundation for forming various prefabricated concrete structures (the regulation specification is 3.0.3, 4.2.1).

However, through a series of research and analysis and engineering practice on the specified connection joint for the steel bar sleeve grouting, the connection technology is not ideal, has a plurality of defects which are difficult to overcome, and has become a bottleneck for restricting the large-scale and high-quality development of the fabricated building, and the main defects are listed as follows:

1. the method can not be suitable for the assembly type connection of the prestressed structure, and the bottleneck problem of hindering the development of the assembly type building is formed to a great extent. Because of the lack of pre-tensioning and post-tensioning prestressed components, the difficulty of comprehensively popularizing the fabricated concrete structure is very high. A large-span and unsupported structure cannot be adopted; the high-strength steel bars and the high-strength concrete cannot be adopted to reduce the manufacturing cost;

2. high cost, complex operation and difficult detection. The "building hour newspaper" at 2016, 4, 11, 7 th edition has reported this: "not only do the consumptive materials many (require strict high strength grouting material and thick and long sleeve again), with high costs, grouting sleeve connects the operating procedure complicacy moreover, the specialty requires highly, and the link that influences the quality in the construction, factor are numerous, and difficult to avoid, difficult to control, more difficult to detect, is difficult to inspect how to the end of the quality of attach fitting? In this regard, technical experts have been concerned about uneasiness ";

3. the grouting construction is obviously affected by the environmental temperature, and the construction region and season are limited. Technical code for grouting connection of steel sleeve connection of reinforcement JGJ 355-20156.3.9 article 2: during grouting construction, the environmental temperature meets the requirements of the operating specification of grouting materials; the construction is not suitable when the environmental temperature is lower than 5 ℃, and the construction cannot be carried out when the environmental temperature is lower than 0 ℃; when the environmental temperature is higher than 30 ℃, measures for reducing the temperature of the grouting material mixture are adopted;

4. the grouting material needs to be used up within 30 minutes after water is added, and can only be discarded after overtime. The final specification of the 'technical specification for grouting and connecting reinforced sleeve' JGJ 355-2015 notes 6.3.9: the fluidity index of the grouting material mixture is gradually reduced along with the time, and in order to ensure grouting construction, the specified grouting material is preferably used up within 30min after water is added. The grouting material mixture can not be mixed with the grouting material and water again, and the grouting material after the specified time is exceeded and the residual grouting material can only be discarded.

The main technology for connecting reinforcing steel bars in the construction industry at present is mechanical connection of the reinforcing steel bars, namely a connection method for transmitting the force in one reinforcing steel bar to the other reinforcing steel bar through the mechanical meshing action of the reinforcing steel bars and connecting pieces or other intervening materials or the pressure bearing action of the end faces of the reinforcing steel bars. The main form of the mechanical connection of the steel bars is threaded connection, and the threaded connection is that special equipment is used for firstly manufacturing steel bar screw heads with corresponding threads at the end parts of the two steel bars, and then connecting the two steel bars by using a connecting sleeve with corresponding internal threads.

Because the reinforcing bars to be connected have deviation and dislocation in radial and axial positions when two prefabricated components of the fabricated building are assembled, the method is clearly defined in the regulation: "the deviation of the connecting steel bar from the central line of the sleeve or the hole is not more than 5 mm" (see "rule" 12.3.2), and because the steel bar embedded in the prefabricated member can not move along the radial direction and the axial direction and can not rotate, and the thread of the steel bar head is pre-processed and embedded in the member together with the steel bar, the implementation of the mechanical connection in the assembled prestressed structure can meet three problems: the first problem is to correct the radial dislocation of the axes of the two reinforcing steel bars; the second problem is that the helical lines of the threads of the two embedded steel bar thread heads have deviation and dislocation, and because the steel bars are fixed in the component and cannot rotate and axially move, when the two steel bars are directly connected by the connecting sleeve, the situation that the threads are interfered and cannot be screwed can occur; the third problem is that on the basis of completing the mechanical connection of the steel bars, pre-tensioning or post-tensioning pre-stressing needs to be applied to the connected steel bars according to the requirements of the pre-stressed structure assembly type building. Furthermore, the tensile strength of the joint must meet the tensile strength requirement specified in 3.0.5 of the mechanical connection of reinforcing bars technical code (JGJ 107-2016). Because of these technical difficulties, the threaded connection technology currently used in the market has not been applied to the fabricated prestressed structure.

Disclosure of Invention

The utility model aims to solve the first technical problem that a but assembled stretch-draw reinforcing bar straight thread connection device is provided, its axis that can two reinforcing bars has under the condition of radial dislocation, realizes the reliable connection between two reinforcing bars.

The utility model aims to solve a second technical problem provide a but assembled stretch-draw reinforcing bar straight thread connection device, it can realize the reliable connection between two reinforcing bars under the condition that two reinforcing bars can not have the deviation dislocation along radial and axial displacement, can not rotate, and the helix of two reinforcing bar silk head threads.

The utility model aims to solve the third technical problem that a but assembled stretch-draw reinforcing bar straight thread connection device is provided, it can be on the basis of accomplishing the assembled reinforcing bar and connecting, to the requirement of prestressing force structure assembly type structure, applys pretension or post-tensioned prestressing force to the reinforcing bar after connecting.

The embodiment of the utility model provides an assembled type stretchable steel bar straight thread connecting device, which comprises a first threaded sleeve, a second threaded sleeve and a connecting sleeve; the connecting sleeve is provided with a central through hole which is communicated along the axial direction, one end of the central through hole is a cylindrical inner hole, and one end of the cylindrical inner hole is communicated with the end face of one end of the connecting sleeve; the cylindrical inner hole of the connecting sleeve, the inner hole of the first screw sleeve and the hole wall of the inner hole of the second screw sleeve are all provided with internal threads, and the outer side surface of the first screw sleeve is provided with external threads; the internal thread of the first screw sleeve is used for being screwed with the external thread of the first steel bar screw head to form a first thread pair, the internal thread of the second screw sleeve is used for being screwed with the external thread of the second steel bar screw head to form a second thread pair, the external thread of the first screw sleeve is screwed with the internal thread of the connecting sleeve to form a third thread pair, and the internal thread of the first screw sleeve and the internal thread of the second screw sleeve are both straight threads; the thread pitch of the first thread pair is equal to that of the second thread pair, and the thread turning direction of the first thread pair is the same as that of the third thread pair; the other end of the central through hole of the connecting sleeve is provided with a conical hole, and the diameter size of the conical hole is gradually reduced from inside to outside; one end of the outer side surface of the second screw sleeve is provided with a first conical surface, and the first conical surface is equal to and contacts with the conical hole of the connecting sleeve in conical degree.

In the assembled type stretchable straight thread connecting device for the steel bar, at least one end of the inner hole of the first thread sleeve is a conical hole, and the diameter of the hole opening of the conical hole is larger than the diameter of the hole bottom of the conical hole; the diameter of the orifice of the conical hole is not larger than the small diameter of the external thread of the first thread sleeve, the diameter of the bottom of the conical hole is not smaller than the large diameter of the internal thread of the first thread sleeve, and the difference between the diameter of the orifice and the diameter of the bottom of the hole is not smaller than twice the maximum deviation value allowed by the axis of the first steel bar thread head and the axis of the second steel bar thread head in the technical regulations of the industry.

In the assembled tenseable steel bar straight thread connecting device, the outer side surface of one end of the second thread insert close to the first thread insert is provided with a second conical surface, the maximum diameter of the second conical surface is smaller than the minor diameter of the external thread of the first thread insert, and the minimum diameter of the second conical surface is not smaller than the major diameter of the internal thread of the second thread insert.

According to the assembled type stretchable straight thread connecting device for the steel bars, the diameter of the opening of the conical hole of the connecting sleeve is larger than or equal to the size which is two times of the maximum allowable deviation value of the axis of the first steel bar wire head and the axis of the second steel bar wire head in the technical specification of the industry and the maximum value of the outer diameter size of the steel bar where the second steel bar wire head is located.

After the technical scheme is adopted, the utility model has the advantages of it is following:

1. one end of a central through hole of a connecting sleeve of the assembly type stretch-drawable steel bar straight thread connecting device of the embodiment of the utility model is provided with a conical hole, and the diameter size of the conical hole is gradually reduced from inside to outside; one end of the outer side surface of the second screw sleeve is provided with a first conical surface, and the first conical surface is equal to and contacts with the conical hole of the connecting sleeve in conical degree; the rotary connecting sleeve can transmit torque and lock by means of the friction action between the conical hole of the connecting sleeve and the first conical surface contact surface of the second screw sleeve, tension is generated on the first reinforcing steel bar thread head and the second reinforcing steel bar thread head, the influence of deviation and dislocation of the spiral line of the first reinforcing steel bar thread head thread and the spiral line of the second reinforcing steel bar thread head thread is avoided, and the rotary connecting sleeve is particularly suitable for assembly type connection of prestressed concrete members, such as pre-tensioning method or post-tensioning method prestressed members;

2. the inner hole of the first screw sleeve is provided with a conical hole at one end close to the second screw sleeve, and the outer side surface of the second screw sleeve at one end close to the first screw sleeve is provided with a second conical surface; in the process that the first thread insert is screwed into the second thread insert, the conical hole of the first thread insert and the second conical surface of the second thread insert can correct the radial deviation between the axis of the first steel bar thread head and the axis of the second steel bar thread head, so that the rotatable connection of the third thread pair is realized;

3. the diameter of the orifice of the conical hole of the connecting sleeve is larger than or equal to the two times of the maximum deviation value allowed by the axis of the first steel bar screw head and the axis of the second steel bar screw head in the technical specification of the industry and the maximum value of the external diameter size of the steel bar where the second steel bar screw head is located.

Drawings

Fig. 1 shows an axial sectional view of a fabricated tensionable reinforcing bar straight-thread connection device according to a first embodiment of the present invention.

Fig. 2 shows an axial section through a first threaded sleeve according to a first embodiment of the invention.

Fig. 3 shows an axial section through a second threaded sleeve according to a first embodiment of the invention.

Fig. 4 shows an axial sectional view of a connection sleeve according to a first embodiment of the invention.

Fig. 5 shows a schematic view of a prefabricated part to which the connecting device according to the first embodiment of the invention is applied, before it is ready for connection.

Fig. 6 shows an application of the prefabricated component, the connecting device according to the first embodiment of the present invention corrects the radial deviation of two steel bars.

Fig. 7 shows a schematic view of the assembly type prefabricated component to which the connecting device according to the first embodiment of the present invention is applied to complete the third thread pair screwing process.

Fig. 8 shows a schematic view of the prefabricated member assembly using the connecting device according to the first embodiment of the present invention to complete the first conical surface contact process between the conical hole of the connecting sleeve and the second screw sleeve.

Fig. 9 is a schematic view showing the application of the connecting device of the first embodiment of the present invention to prestress tension in the prefabricated parts.

Fig. 10 shows a cross-sectional view a-a of fig. 7, wherein the coupling sleeve is shaped as a hexagonal polygonal prism.

Fig. 11 shows a schematic view of the prefabricated member assembly using the connecting device according to the second embodiment of the present invention to complete the first conical surface contact process between the conical hole of the connecting sleeve and the second screw sleeve.

Fig. 12 is a schematic view showing the application of the connecting device of the second embodiment of the present invention to prestress tension in the prefabricated parts.

Fig. 13 shows a schematic view of a prefabricated part to which the connecting device according to the third embodiment of the present invention is applied before it is ready for connection.

Fig. 14 is a schematic view showing a third thread pair screwing process of the connecting device according to the third embodiment of the present invention applied to prefabricated parts.

Fig. 15 shows a schematic view of the connecting device according to the third embodiment of the present invention for completing the first conical surface contact process between the conical hole of the connecting sleeve and the second screw sleeve and applying the pre-stress tension force.

Fig. 16 shows an axial sectional view of an assembled tensionable steel bar straight thread connection device according to the fourth embodiment of the present invention, in which two steel bar thread ends are extended thread end lengths.

Fig. 17 shows an axial sectional view of an assembled tensionable steel bar straight thread connection device according to the fifth embodiment of the present invention, wherein two steel bar thread ends are extended thread end lengths.

Detailed Description

Representative applications of the device according to the present patent application will be described in this section, these examples being provided to aid understanding of the embodiments. It will thus be apparent to one skilled in the art that the embodiments may be practiced without some or all of these specific details. In other instances, well known process steps have not been described in detail in order to not unnecessarily obscure the embodiments. Other applications are also possible, so that the following examples should not be considered limiting.

In the following detailed description, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration specific embodiments in accordance with the embodiments. Although these embodiments are described in sufficient detail to enable those skilled in the art to practice the embodiments, it is understood that these examples are not limiting; such that other embodiments may be used and modifications may be made without departing from the spirit and scope of the embodiments.

Fig. 1 is an axial sectional view of a fabricated stretchable steel bar straight-thread connecting device according to a first embodiment of the present invention, in which two steel bar ends are standard end lengths and the thread directions of the steel bar ends are opposite. Fig. 2 shows an axial sectional view of a first thread insert according to a first embodiment of the invention, wherein the first thread insert is provided with a conical bore and is further provided with a step projecting radially outwards. Fig. 3 shows an axial sectional view of a second thread insert according to a first embodiment of the invention, wherein the second thread insert is provided with a second conical surface, the conicity of which equals the conicity of the conical bore of the first thread insert, the minimum diameter of which equals the bore bottom diameter of the conical bore of the first thread insert. Fig. 4 shows an axial sectional view of a connection sleeve according to a first embodiment of the invention. Referring to fig. 1 to 4, the assembly type tensionable reinforcing bar straight thread connection device according to the first embodiment of the present invention includes a first threaded sleeve 1, a second threaded sleeve 2 and a connection sleeve 3.

The connecting sleeve 3 is provided with a central through hole which is through along the axial direction, one end of the central through hole is a cylindrical inner hole 30, and one end of the cylindrical inner hole 30 is through the end face of one end of the connecting sleeve 3; the hole wall of the cylindrical inner hole 30 of the connecting sleeve 3, the hole wall of the inner hole 10 of the first screw sleeve 1 and the hole wall of the inner hole 20 of the second screw sleeve 2 are all provided with internal threads, and the outer side surface of the first screw sleeve 1 is provided with external threads; the internal thread of the first thread insert 1 is screwed with the external thread of the first steel bar screw head 81 to form a first thread pair M1, the internal thread of the second thread insert 2 is screwed with the external thread of the second steel bar screw head 82 to form a second thread pair M2, the external thread of the first thread insert 1 is screwed with the internal thread of the connecting sleeve 3 to form a third thread pair M3, and the internal thread of the first thread insert 1 and the internal thread of the second thread insert 2 are both straight threads; the thread pitch of the first thread pair M1 is equal to that of the second thread pair M2 (namely, the thread pitch of the internal thread of the first thread sleeve 1, the thread pitch of the external thread of the first steel bar thread head 81, the thread pitch of the internal thread of the second thread sleeve 2 and the thread pitch of the external thread of the second steel bar thread head 82 are all equal), and the thread turning direction of the first thread pair M1 is equal to that of the third thread pair M3 (namely, the thread turning direction of the internal thread of the first thread sleeve 1, the thread turning direction of the external thread of the first steel bar thread head 81, the thread turning direction of the external thread of the first thread sleeve 1 and the thread turning direction of the internal thread of the connecting sleeve 3 are all equal); wherein, the other end of the central through hole of the connecting sleeve 3 is provided with a conical hole 31, the diameter size of the conical hole 31 is gradually reduced from inside to outside (in the embodiment, the orifice diameter D4 of the conical hole 31 of the connecting sleeve 3 is smaller than the hole bottom diameter D4 of the conical hole 31); one end of the outer side surface of the second thread insert 2 is provided with a first conical surface 21, and the first conical surface 21 has the same taper as and contacts with the conical hole 31 of the connecting sleeve 3.

In the present embodiment, the thread direction of the first thread pair M1 is opposite to the thread direction of the second thread pair M2 (i.e., the thread direction of the internal thread of the first thread insert 1 and the thread direction of the external thread of the first thread 81 are opposite to the thread direction of the internal thread of the second thread insert 2 and the thread direction of the external thread of the second thread 82).

In the embodiment, one end of the inner hole 10 of the first thread insert 1 is a conical hole 12, and the diameter D1 of the opening of the conical hole 12 is larger than the diameter D1 of the bottom of the conical hole; the diameter D1 of the opening of the conical hole is not larger than the minor diameter of the external thread of the first thread insert 1, the diameter D1 of the bottom of the conical hole is not smaller than the major diameter of the internal thread of the first thread insert 1, and the difference between the diameter D1 of the opening and the diameter D1 of the bottom of the conical hole is not smaller than twice the maximum deviation value allowed by the axis of the first reinforcing steel wire head 81 and the axis of the second reinforcing steel wire head 82 in the technical regulations of the industry. For example, when the selected technical specification is "technical specification for prefabricated concrete structures" (JGJ 1-2014), article 12.3.2 specifies: "the connecting steel bar is not deviated from the center line of the sleeve or the hole by more than 5 mm", if the specification of 12.3.2 in the technical code of prefabricated concrete structure is followed, the difference between the diameter D1 of the hole opening and the diameter D1 of the hole bottom should be 10mm or more. If other technical rules are selected, the values specified by the other technical rules are used as the standard.

In this embodiment, the second thread insert 2 is provided with a second conical surface 22 on the outer side surface near one end of the first thread insert 1, the maximum diameter D3 of the second conical surface 22 is smaller than the minor diameter of the external thread of the first thread insert 1, and the minimum diameter D3 of the second conical surface 22 is not smaller than the major diameter of the internal thread of the second thread insert 2.

In the present embodiment, the taper of the second conical surface 22 of the second thread insert 2 is equal to the taper of the conical hole 12 of the first thread insert 1, and the minimum diameter d3 of the second conical surface 22 is equal to the hole bottom diameter d1 of the conical hole 12 of the first thread insert 1.

In this embodiment, the maximum diameter D2 of the first conical surface 21 of the second nut 2 is smaller than the minor diameter of the external thread of the first nut 1, and the minimum diameter D2 of the first conical surface 21 is not smaller than the major diameter of the internal thread of the second nut 2.

Optionally, K is more than or equal to 1: 15 and less than or equal to 1: 1.207 of the taper of the first conical surface 21 of the second thread insert 2. As shown in fig. 3, taking the first conical surface 21 as an example, the calculation formula of the taper K is (D2-D2)/L.

In this embodiment, the outer side surface of one end of the first thread insert 1 is provided with a first step 11 protruding radially outward. The minimum size of the first step 11 is larger than the major diameter size of the external thread of the first thread insert 1, and the first step 11 is used for stopping the connecting sleeve 3 and rotating the first thread insert 1. The first step 11 may have a hexagonal polygonal prism, a cylinder, or other shape compatible with a rotary tool.

The coupling sleeve 3 may have the shape of a hexagonal polygonal prism or a cylinder, or other shape compatible with a rotary tool. In the present embodiment, the connecting sleeve 3 has a hexagonal polygonal prism shape (as shown in fig. 10).

The utility model discloses connection method can be applicable to the straight thread reinforcing bar silk head of various types and connect, combines the condition of job site, selects two reinforcing bar silk heads all to be standard length silk heads, or all to be extension length silk heads, or a reinforcing bar silk head is standard length, and another reinforcing bar silk head is extension length. The connection method provided by the embodiment of the utility model is also suitable for different combinations of the screw thread turning directions.

With reference to fig. 5 to 10, a process of connecting two reinforcing bars of prefabricated components and applying a tensile force by using a connecting device according to a first embodiment of the present invention will be described, wherein two reinforcing bar ends have a standard length and the thread directions are opposite; optionally, in the present embodiment, the pitch of the first thread pair M1 is equal to the pitch of the third thread pair M3. The specific implementation process is as follows:

1) firstly, a first reinforcing steel bar screw 81 with a straight thread and a second reinforcing steel bar screw 82 with a straight thread are respectively processed at the ends of the first reinforcing steel bar 8a and the second reinforcing steel bar 8b by special equipment, wherein the first reinforcing steel bar screw 81 is a right-handed screw, and the second reinforcing steel bar screw 82 is a left-handed screw.

2) As shown in fig. 5, when the concrete is precast or at a construction site, the steel bars with the processed thread ends are pre-embedded, the first steel bar 8a is pre-embedded in the first prefabricated part 7a, and the second steel bar 8b is pre-embedded in the second prefabricated part 7 b. Screwing the internal thread of the first thread sleeve 1 and the external thread of the first steel bar thread head 81 to form a first thread pair M1; the connecting sleeve 3 is sleeved into the second steel bar head 82, the internal thread of the second thread sleeve 2 is screwed with the external thread of the second steel bar head 82, and the second thread sleeve 2 is screwed into the second thread sleeve 2 to abut against the tail end of the second steel bar head 82, so that a second thread pair M2 is formed. At the construction site, the second prefabricated part 7b is seated on the first prefabricated part 7a, and the intermediate layer 7c is "set mortar" of the cement paste.

3) In the example of fig. 5, there is a radial misalignment T of 5mm between the axis of the first wire head 81 and the axis of the second wire head 82 (required by "code" 12.3.2: when the connecting reinforcement is inclined, straightening should be performed. The connecting steel bar deviates from the central line of the sleeve or the hole by not more than 5mm), because the difference between the opening diameter D1 and the hole bottom diameter D1 of the conical hole 12 of the first screw sleeve 1 is more than or equal to 10mm, and the minimum diameter D3 of the second conical surface 22 of the second screw sleeve 2 is equal to the hole bottom diameter D1 of the conical hole 12 of the first screw sleeve 1, the outer side surface of the second conical surface 22 of the second screw sleeve 2 which is screwed on the second steel bar wire head 82 in advance above the first screw sleeve 1, where the minimum diameter D3 is located, always falls within the range of the conical hole 12 of the first screw sleeve 1 along the axial direction of the first steel bar wire head 81.

4) In the example of fig. 6, the first step 11 of the first screw sleeve 1 is rotated to make the first screw sleeve 1 screwed in the direction of the second screw sleeve 2, when the inner conical surface of the conical hole 12 of the first screw sleeve 1 contacts the outer side surface of the second conical surface 22 of the second screw sleeve 2 where the minimum diameter d3 is located, the screwing is continued, the screwing torque is conducted through the internal thread of the first screw sleeve 1 and the conical surface of the conical hole 12 is increased, the screwing torque is enough to push the axis of the first reinforcing steel wire head 81 and the axis of the second reinforcing steel wire head 82 to approach each other along the conical surface taper of the conical hole 12 of the first screw sleeve 1, the radial offset is corrected, and the radial offset value T is reduced from 5mm in the example of fig. 5 to 2mm in the example of fig. 6.

5) In the example of fig. 7, the first thread insert 1 is rotated in the direction of making the first thread insert 1 approach the second thread insert 2 until the first thread insert 1 cannot rotate (at this time, the outer side surface where the minimum diameter d3 of the second conical surface 22 of the second thread insert 2 is located is attached to the inner side surface where the hole bottom diameter d1 of the conical hole 12 of the first thread insert 1 is located and abuts against the first thread insert 1, so that the first thread insert 1 cannot rotate and screw in the direction of the second thread insert 2 any more), and the radial misalignment between the axis of the first steel wire head 81 and the axis of the second steel wire head 82 is corrected to T ═ 0, that is, the first steel wire head 81 and the second steel wire head 82 are coaxial.

6) The rotary tool 6 is rotated to screw the connecting sleeve 3 in the direction of the first thread insert 1, and the internal thread of the connecting sleeve 3 is screwed with the external thread of the first thread insert 1 to form a third thread pair M3.

7) In the example of fig. 8, the rotation tool 6 is rotated until the top end of the coupling sleeve 3 abuts against the first step 11 of the first thread insert 1. Because the screw thread turning direction of the screw thread pair M3 is the same as the screw thread turning direction of the screw thread pair M1, the first thread insert 1 is driven to rotate in the same direction by continuously rotating the rotary tool 6 to enable the connecting sleeve 3 to rotate towards the tail end of the first steel bar thread 81, so that the first thread insert 1 is screwed towards the tail end of the first steel bar thread 81; the inner side surface where the hole bottom diameter d1 of the conical hole 12 of the first thread insert 1 is located will be out of contact with the outer side surface where the minimum diameter d3 of the second conical surface 22 of the second thread insert 2 is located, and at the same time the conical surface of the conical hole 12 of the first thread insert 1 will also be out of contact with the second conical surface 22 of the second thread insert 2. The rotating tool 6 is further rotated to advance the connecting sleeve 3 until the conical surface of the conical bore 31 of the connecting sleeve 3 contacts the first conical surface 21 of the second thread insert 2.

The thread direction of the first thread pair M1 is opposite to the thread direction of the second thread pair M2, so that when the connecting sleeve 3 is screwed into the direction of the tail end of the first reinforcing steel bar thread 11, the second thread sleeve 2 is driven to screw into the direction opposite to the screwing direction of the connecting sleeve 3 (screw into the direction of the tail end of the second reinforcing steel bar thread 82) until the end face of the second thread sleeve 2 abuts against the tail end of the second reinforcing steel bar thread 82.

8) In the example of fig. 9, the first step 11 of the first thread insert 1 is rotated toward the tail end of the first wire 81, so that the first thread insert 1 is screwed into and against the tail end of the first wire 81. Rotating the rotating tool 6, forcibly rotating the connecting sleeve 3 towards the tail end of the first reinforcing steel wire head 81, and transmitting the torque generated by rotation to the first thread pair M1 through the third thread pair M3 and finally to the external thread of the first reinforcing steel wire head 81; the torque generated by rotating the connecting sleeve 3 is transmitted to the second thread pair M2 through the friction between the conical surface of the conical hole 31 of the connecting sleeve 3 and the contact surface of the first conical surface 21 of the second thread insert 2, and finally transmitted to the external thread of the second steel bar thread head 82, because the first steel bar 8a and the second steel bar 8b are fixed in the corresponding prefabricated components and cannot move and rotate, the pre-tensioning force is generated on the first steel bar 8a and the second steel bar 8b, the connecting sleeve 3 is locked through rotating forcibly, and the connection is finished.

Taking a steel bar with the specification of phi 25 as an example, under the condition that the connection length is 10 times of the diameter of the steel bar, the offset angle alpha of the central line of the connecting device to the initial position of the axis of the steel bar after the connection is finished is about 1 degree.

Fig. 11 to 12 are schematic diagrams illustrating a process of connecting a straight thread of a fabricated tensionable reinforcing bar according to a second embodiment of the present invention, wherein the thread directions of the first reinforcing bar thread 81 and the second reinforcing bar thread 82 are the same (right-hand thread is selected in this example). The second embodiment is mainly different from the first embodiment in that the taper of the second conical surface 22 of the second nut 2 is smaller than the taper of the conical surface of the conical hole 12 of the first nut 1, and the minimum diameter d3 of the second conical surface 22 of the second nut 2 is larger than the hole bottom diameter d1 of the conical hole 12 of the first nut 1.

The connection implementation procedure of this second embodiment differs from the connection implementation procedure of the first embodiment described above mainly in procedures 7 and 8:

7) in the example of fig. 11, the rotation of the rotary tool 6 is continued until the conical surface of the conical bore 31 of the coupling sleeve 3 comes into contact with the first conical surface 21 of the second thread insert 2. Because the second thread pair M2 of the internal thread of the second thread sleeve 2 and the external thread of the second steel wire head 82 is a right-hand thread, the first thread pair M1 of the internal thread of the first thread sleeve 1 and the external thread of the first steel wire head 81 is a right-hand thread, and the thread pitch of M1 is equal to the thread pitch of M2, the rotary tool 6 is rotated at this time, and the connecting sleeve 3, the second thread sleeve 2 and the first thread sleeve 1 can be synchronously screwed in the direction of the tail end of the first steel wire head 81.

8) In the example of fig. 12, the connection sleeve 3, the second thread insert 2, and the first thread insert 1 are synchronously screwed in until the tail end of the first thread insert 1 abuts against the tail end of the first rebar thread 81 and cannot be screwed in, the connection sleeve 3 is forcibly rotated, and the connection is finished.

Fig. 13 to 15 are schematic views showing a straight thread connection process of a fabricated tensionable reinforcing bar according to a third embodiment of the present invention, wherein the thread directions of the first reinforcing bar head 81 and the second reinforcing bar head 82 are opposite, and optionally, in this embodiment, the pitch of the first thread pair M1 is equal to the pitch of the third thread pair M3. The third embodiment differs from the first embodiment mainly in that:

a. the first thread insert 1 does not comprise a conical bore 12.

b. The second thread insert 2 does not comprise the second conical surface 22.

c. The conical bore 31 of the coupling sleeve 3 is formed by combining two conical surfaces of different conicity, namely a conical surface 31a and a conical surface 31 b. The taper of the conical surface 31a is equal to the taper of the first conical surface 21 of the second thread insert 2, and the taper of the conical surface 31b is greater than the taper of the conical surface 31a, so as to shorten the axial distance from the conical surface 31a to the internal thread of the connecting sleeve 3, thereby shortening the length of the connecting sleeve 3 and saving materials.

d. The diameter d4 of the opening of the conical hole 31 of the connecting sleeve 3 is more than or equal to the maximum value of the two times of the maximum deviation value allowed by the technical regulations of the axis of the first reinforcing steel wire head 81 and the axis of the second reinforcing steel wire head 82 + the outer diameter of the second reinforcing steel 8b where the second reinforcing steel wire head 82 is located. For example, when the selected technical specification is "technical specification for prefabricated concrete structures" (JGJ 1-2014), article 12.3.2 specifies: "the deviation of the connecting steel bar from the central line of the sleeve or the hole should not exceed 5 mm", if the specification of 12.3.2 in the technical code of prefabricated concrete structure is followed, 10mm should be taken, that is, the diameter d4 of the opening of the conical hole 31 of the connecting sleeve 3 is more than or equal to 10mm + the maximum value of the outer diameter of the second steel bar 8b where the second steel bar thread 82 is located. If other technical rules are selected, the values specified by the other technical rules are used as the standard.

e. The outer side surface of one end of the first thread insert 1 is provided with a second step 11a which is inwards recessed along the radial direction, and the maximum size of the second step 11a is smaller than the small-diameter size of the external thread of the first thread insert 1.

The utility model discloses but assembled stretch-draw reinforcing bar straight thread connection concrete implementation process as follows:

2) In the example of fig. 13, the steel bars with the processed ends are embedded at the time of prefabricating concrete or at the construction site, the first steel bar 8a is embedded in the first prefabricated part 7a, and the second steel bar 8b is embedded in the second prefabricated part 7 b. Screwing the internal thread of the first thread sleeve 1 and the external thread of the first steel bar thread head 81 to form a first thread pair M1; the connecting sleeve 3 is sleeved into the second steel bar thread 82, and then the internal thread of the second thread sleeve 2 is screwed with the external thread of the second steel bar thread 82 to form a second thread pair M2. At the construction site, the second prefabricated part 7b is seated on the first prefabricated part 7a, and the intermediate layer 7c is "set mortar" of the cement paste.

3) In the example of fig. 13, it is simulated that the radial misalignment T of the axis of the first reinforcing wire head 81 from the axis of the second reinforcing wire head 82 is 5mm (required by "rule" 12.3.2: when the connecting reinforcement is inclined, straightening should be performed. The connecting steel bars are not deviated from the center line of the sleeve or the hole by more than 5 mm). In this embodiment, the orifice diameter d4 of the conical bore 31 of the coupling sleeve 3 is ≧ 10mm + the maximum of the outer diameter of the second reinforcing bar 8 b.

4) In the example of fig. 14, the internal thread of the connecting sleeve 3 can be screwed directly with the external thread of the first thread insert 1 by means of the size of the opening diameter d4 of the conical bore 31 of the connecting sleeve 3, forming the thread pair M3. The rotary tool 6 is rotated to advance the coupling sleeve 3 in the direction of the first thread insert 1. Until the conical surface of the conical hole 31 of the connecting sleeve 3 contacts the first conical surface 21 of the second thread insert 2; the connecting sleeve 3 is screwed into the first thread sleeve 1 continuously to drive the second thread sleeve 2 to rotate, and the second thread sleeve 2 is screwed into the tail direction of the second steel bar thread head 82 until the second thread sleeve is dead and fixed (because the second thread pair M2 is a left-hand thread, namely, the internal thread of the second thread sleeve 2 and the external thread of the second steel bar thread head 82 are both left-hand threads); meanwhile, the torque screwed into the connecting sleeve 3 is transmitted through the conical surface of the conical hole 31 of the connecting sleeve 3 and the thread pair M3, so that the axis of the second steel wire head 82 and the axis of the first steel wire head 81 are pushed to be close to each other along the taper of the first conical surface 21 of the second thread sleeve 2, the radial deviation of the second steel wire head is corrected, and the radial dislocation value T is reduced from the initial 5mm to 2 mm.

5) In the example of fig. 15, the rotation tool 6 is continuously rotated until the conical surface of the conical hole 31 of the coupling sleeve 3 is completely in contact with the first conical surface 21 of the second thread insert 2, and at the same time, the radial misalignment between the axis of the first reinforcing-wire head 81 and the axis of the second reinforcing-wire head 82 is corrected to T ═ 0. And rotating the second step 11a of the first thread insert 1 towards the tail end of the first steel wire rod 81 to make the first thread insert 1 screwed in and prop against the tail end of the first steel wire rod 81. Rotating the rotating tool 6, forcibly rotating the connecting sleeve 3 towards the tail end of the first reinforcing steel wire head 81, and transmitting the torque generated by rotation to the first thread pair M1 through the third thread pair M3 and finally to the external thread of the first reinforcing steel wire head 81; the torque generated by rotating the connecting sleeve 3 is transmitted to the second thread pair M2 through the friction between the conical surface of the conical hole 31 of the connecting sleeve 3 and the contact surface of the first conical surface 21 of the second thread insert 2, and finally transmitted to the external thread of the second steel bar thread head 82, because the first steel bar 8a and the second steel bar 8b are fixed in the corresponding prefabricated components and cannot move and rotate, the pre-tightening tension force is generated on the first steel bar 8a and the second steel bar 8b, the connecting sleeve 3 is tightly screwed and locked by force, and the connection is finished.

Fig. 16 shows an axial cross-sectional view of a fabricated tensionable steel bar straight-thread connecting device according to a fourth embodiment of the present invention, wherein the first steel bar thread 81 and the second steel bar thread 82 are both extended thread length. The main difference between this fourth embodiment and the first embodiment lies in that, according to the utility model discloses the straight threaded connection device of assembled tensioning reinforcing bar of fourth embodiment includes two

lock nuts

4a and 4b, and lock nut 4a spiral cover connects in first reinforcing bar thread 81, and lock nut 4b spiral cover connects in second reinforcing bar thread 82. The end surface of the lock nut 4a abuts against the end surface of the first thread insert 1, and the end surface of the lock nut 4b abuts against the end surface of the coupling sleeve 3. The first thread insert 1 and the coupling sleeve 3 may be positioned at appropriate positions within the length range of the head of the reinforcing bar using the locking nuts 4a and 4b so as not to be moved in the direction of the tail of the head of the reinforcing bar.

In other embodiments, the lock nut 4a may be screwed only between the tail end of the first steel wire 81 and the end surface of the first nut 1, or the lock nut 4b may be screwed only between the tail end of the second steel wire 82 and the end surface of the connecting sleeve 3, and after the connection is completed, the end surface of the

lock nut

4a or 4b abuts against the corresponding end surface of the first nut 1 or the connecting sleeve 3.

Fig. 17 shows an axial cross-sectional view of an assembled tensionable steel bar straight-thread connecting device according to the fifth embodiment of the present invention, wherein the first steel bar thread 81 and the second steel bar thread 82 are both the extension thread length. The main differences between this fifth embodiment and the fourth embodiment:

a. the locking nut 4c is spirally sleeved on the second steel bar thread 82, an external thread is arranged on the outer side face of the locking nut 4c, the large diameter size of the external thread of the locking nut 4c is smaller than the orifice diameter d4 of the conical hole 31 of the connecting sleeve 3, and the conical hole 31 of the connecting sleeve 3 can conveniently penetrate through the external thread.

b. Still include lock nut 4d, the external screw thread of lock nut 4c is cup jointed in to the internal thread spiral of lock nut 4 d.

c. The end face of one end of the lock nut 4d is provided with a conical hole, and the outer side face of one end of the connecting sleeve 3 is provided with a conical face 32. The conical surface of the conical hole of the lock nut 4d abuts against the conical surface 32 of the coupling sleeve 3, and the rigidity of the conical surface 32 portion of the coupling sleeve 3 is enhanced. When the reinforcing steel bar is subjected to axial tensile stress in the member, the axial tensile stress acts on the conical hole 31 of the connecting sleeve 3, and the locking nut 4d can enhance the rigidity of the part of the connecting sleeve 3 and ensure that the conical hole 31 of the connecting sleeve 3 is not expanded from inside to outside.

The utility model discloses connecting device is particularly useful for the steel bar connection between the prestressing force prefabricated component and cast-in-place and post-cast concrete structure between, and its easy operation is convenient, does not receive the ambient temperature restriction, does not have the maintenance period after connecting, has easy detection, zero energy consumption, no auxiliary material, low-cost advantage.

Claims

1. An assembled type stretchable steel bar straight thread connecting device comprises a first threaded sleeve, a second threaded sleeve and a connecting sleeve; the connecting sleeve is provided with a central through hole which is communicated along the axial direction, one end of the central through hole is a cylindrical inner hole, and one end of the cylindrical inner hole is communicated with the end face of one end of the connecting sleeve; the cylindrical inner hole of the connecting sleeve, the inner hole of the first screw sleeve and the hole wall of the inner hole of the second screw sleeve are all provided with internal threads, and the outer side surface of the first screw sleeve is provided with external threads; the internal thread of the first screw sleeve is used for being screwed with the external thread of the first steel bar screw head to form a first thread pair, the internal thread of the second screw sleeve is used for being screwed with the external thread of the second steel bar screw head to form a second thread pair, the external thread of the first screw sleeve is screwed with the internal thread of the connecting sleeve to form a third thread pair, and the internal thread of the first screw sleeve and the internal thread of the second screw sleeve are both straight threads; the thread pitch of the first thread pair is equal to that of the second thread pair, and the thread turning direction of the first thread pair is the same as that of the third thread pair; the connecting sleeve is characterized in that a conical hole is formed in the other end of the central through hole of the connecting sleeve, and the diameter size of the conical hole is gradually reduced from inside to outside; and a first conical surface is arranged at one end of the outer side surface of the second screw sleeve, and the first conical surface is equal to and contacts with the conical hole of the connecting sleeve in conical degree.

2. The fabricated tensionable reinforcing straight-threaded connection of claim 1, wherein the thread direction of the first thread pair is opposite to the thread direction of the second thread pair.

3. The assembly type tensable reinforcing bar straight-thread connecting device according to claim 1, wherein at least one end of the inner hole of said first screw sleeve is a conical hole, the diameter of the opening of said conical hole is larger than the diameter of the bottom of said conical hole; the diameter of the orifice of the conical hole is not larger than the small diameter of the external thread of the first thread sleeve, the diameter of the bottom of the conical hole is not smaller than the large diameter of the internal thread of the first thread sleeve, and the difference between the diameter of the orifice and the diameter of the bottom of the hole is not smaller than twice the maximum deviation value allowed by the axis of the first steel bar thread head and the axis of the second steel bar thread head in the technical regulations of the industry.

4. The assembled tenseable reinforcing bar straight thread connecting device of claim 1, wherein the second thread insert is provided with a second conical surface on the outer side surface near one end of the first thread insert, the maximum diameter of the second conical surface is smaller than the minor diameter of the external thread of the first thread insert, and the minimum diameter of the second conical surface is not smaller than the major diameter of the internal thread of the second thread insert.

5. The assembly type tensionable reinforcing bar straight thread connection device of claim 4, wherein the taper of the second conical surface of the second screw sleeve is not more than the taper of the conical hole of the first screw sleeve, and the minimum diameter of the second conical surface is not less than the hole bottom diameter of the conical hole of the first screw sleeve.

6. The fabricated tensionable reinforcing bar straight-thread connection device of claim 1, wherein the maximum diameter of the first conical surface of the second barrel is smaller than the external thread minor diameter of the first barrel, and the minimum diameter of the first conical surface is not smaller than the internal thread major diameter of the second barrel.

7. The fabricated tensionable reinforcing bar straight-thread connecting device as claimed in claim 1, wherein the outer side of one end of said first thread insert is provided with a step protruding radially outward.

8. The apparatus of claim 7, wherein the step has a hexagonal polygonal prism or cylinder shape.

9. The assembled tenseable reinforcing bar straight thread connecting device according to claim 1, wherein the diameter of the opening of the conical hole of the connecting sleeve is greater than or equal to twice the maximum deviation value allowed by the technical regulations of the axis of the first reinforcing bar thread head and the axis of the second reinforcing bar thread head + the maximum value of the outside diameter of the reinforcing bar where the second reinforcing bar thread head is located.

10. A fabricated tensionable reinforcing bar straight-thread connection apparatus as claimed in claim 1, wherein said connection sleeve has an external shape of a hexagonal polygonal prism or a cylinder.

11. The assembly type tensionable reinforcing steel bar straight thread connecting device of claim 1, further comprising one or more locking nuts, wherein the locking nut is screwed on the first reinforcing steel bar end and/or the second reinforcing steel bar end, and the end surface of each locking nut abuts against the end surface of the corresponding first screw sleeve or connecting sleeve.

12. The fabricated stretchable steel bar straight thread connection device according to claim 11, wherein an end surface of one end of the lock nut is provided with a cylindrical hole or a conical hole, and a cylindrical surface or a conical surface in the cylindrical hole or the conical hole abuts against a corresponding side surface of the connection sleeve.