Pipe expanding machining device

Abstract

The utility model discloses an expanded tube processing device, which adopts a roller to replace a thread rolling wheel on a thread rolling machine, and is additionally provided with an inner die, a turntable and a cutting gun. A spiral groove is machined in the outer circumferential face of the rolling wheel, a spiral protrusion is machined on the outer circumferential face of the inner die, and the spiral protrusion is matched with the spiral groove. A rotary table is arranged in front of the roller and provided with a cutting gun, and the distance between a nozzle of the cutting gun and the rotary table is equal to the pipe expanding length. According to the utility model, the extrusion deformation and cutting of the expanded tube are intermittently and continuously carried out on one device, and semi-automatic batch production is realized on the basis of automatic control.

Description

Technical Field

[0001] This utility model applies to the field of fasteners and relates to the processing of expansion bolts, specifically a device for processing expansion tube components of expansion bolts. Background Technology

[0002] Expansion bolts are commonly used fasteners for installing workpieces on walls. A typical expansion bolt structure is shown in the attached image. Figure 1 As shown, the expansion bolt is assembled from a screw 1, a nut 2, a washer 3, and an expansion tube 4. The tail of the screw is machined with a tapered surface, and the expansion tube has a notch at its mating point with the tapered surface. In use, tightening the nut 2 moves the screw 1 to the right, bringing the tapered surface into contact with the expansion tube 4, causing it to expand and its outer diameter to increase. The notch facilitates the outward expansion of the expansion tube. The tightening principle of this expansion bolt relies on the friction between the expansion tube and the inner wall of the wall hole. This friction originates from the elastic force generated by the tapered surface at the tail of the screw, causing the expansion tube to expand. Over time, the elastic stress gradually disappears, and the friction between the expansion tube and the inner wall of the wall hole gradually decreases, weakening the force holding the workpiece to the wall and causing it to loosen.

[0003] To prevent the expansion bolts from loosening and to achieve a secure, detachable installation, the applicant modified the structure of the expansion bolts to include... Figure 2 As shown, the structure still uses a screw 1, nut 2, washer 3, and expansion tube 4 for assembly. However, the conical surface at the tail of the screw is replaced with a frustum-shaped cap 5, and the expansion tube 4 is changed to a spiral arch 7. A protruding tip 6 is provided on the outer surface of the arch 7. The protruding tip 6 is embedded into the inner wall of the wall hole by the deformation of the expansion tube 4, achieving a fixed and anti-loosening mechanism. To facilitate the manufacturing of the expansion tube and achieve low-cost manufacturing of expansion bolts, this utility model expansion tube processing device is designed. Utility Model Content

[0004] The technical problem solved by this utility model is to provide a tube expansion processing device that can realize the processing of arched tube expansion in one station, thereby achieving low-cost manufacturing of tube expansion.

[0005] The technical solution adopted in this utility model is as follows: This utility model tube expansion processing device is an improvement on the thread rolling machine, replacing the thread rolling wheel with two rollers (left and right), and adding an inner mold, a turntable, and a cutting torch. A spiral groove is machined on the outer circumference of the rollers; this spiral groove is used to extrude and form the outer surface of the expanded tube, corresponding to the spiral arched outer surface of the expanded tube. A spiral protrusion is machined on the outer circumference of the inner mold; this spiral protrusion is used to extrude and form the inner surface of the expanded tube, corresponding to the spiral arched inner surface of the expanded tube. The spiral groove and spiral protrusion cooperate to ensure that the protrusion tip is located on the arch. A turntable is set in front of the rollers, and a cutting torch is mounted on the turntable. The distance between the cutting torch nozzle and the turntable corresponds to the length of the expanded tube. The rotation center of the turntable is consistent with the axis of symmetry of the two rollers, ensuring that the distance between the cutting torch and the outer surface of the finished tube is approximately uniform.

[0006] Furthermore, the turntable is a gear turntable, driven to rotate by a drive gear. The turntable is rotatably connected to a rotating shaft via a bearing. The rotating shaft has a central hole, and a cylinder is installed inside the central hole. The cylinder rod end is rotatably connected to a top block, which cooperates with the inner mold to restrict the movement of the inner mold in the direction of the rotation center line.

[0007] Furthermore, the cutting gun is a waterjet cutting gun, the turntable is fixed by a rotating shaft and rotates, and the front end of the rotating shaft is machined with a water inlet, which is connected to the waterjet cutting gun through a water pipe fixed on the turntable.

[0008] Furthermore, to ensure smooth extrusion deformation of the raw material tube, the outer circumferential diameter of the inner mold corresponds to the inner diameter of the raw material tube of the expansion tube. In this way, the raw material tube only undergoes external expansion deformation on the surface that contacts the spiral protrusion and groove.

[0009] Furthermore, the cutting gun can also be a laser cutting gun.

[0010] Furthermore, to reduce equipment investment, the tube expansion processing device is an improvement on the thread rolling machine, only changing the mold and adding a turntable and cutting torch components.

[0011] Furthermore, to reduce the friction between the inner mold and the raw material tube, lubricating oil or grease is applied to the outer surface of the inner mold.

[0012] The beneficial effects of this utility model are: it can directly utilize a thread rolling machine, saving equipment investment; it replaces the thread rolling die with rollers, increasing the inner die, which is within the scope of conventional production die investment; the extrusion and cutting of the tube are carried out continuously on one device, achieving semi-automatic mass production based on automatic control. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of a commonly used expansion bolt structure;

[0014] Figure 2 This is a schematic diagram of the applicant's new expansion bolt structure;

[0015] Figure 3 This is a front view schematic diagram of Embodiment 1, and also Figure 4 AA sectional view;

[0016] Figure 4 This is a top view of Example 1;

[0017] Figure 5 yes Figure 3 BB cross-sectional diagram;

[0018] Figure 6 This is a top view of Example 2;

[0019] Figure 7 This is a top view of Example 3;

[0020] In the diagram: 1-Screw, 2-Nut, 3-Washer, 4-Expansion tube, 5-Rod cap, 6-Protruding tip, 7-Arch;

[0021] 11-Roller, 12-Raw material pipe, 13-Inner mold, 14-Water cutting gun, 15-Turntable, 16-Rotating shaft, 17-Water inlet, 18-Finished product pipe, 19-Cylinder, 20-Bearing, 21-Drive gear, 22-Laser cutting gun, 23-Top block, 24-Top rod, 25-Top ball. Detailed Implementation

[0022] The following "left and right" are supplementary. Figure 3 and attached Figure 4 The left and right sides, the following "front and back" are attached. Figure 4 The directions are both upward and downward. Automatic control is existing technology and is not the focus of this utility model's structural description. Structures not described in detail in this utility model, such as gear rotation and engagement, fixing of the cutting torch, and rotational connection of the top block, are all existing technologies. Example 1

[0023] This embodiment of the tube expansion processing device is an improvement on the thread rolling machine, a specialized piece of equipment for producing lead screws. The blank rod is directly processed into a lead screw by being bitten into rotating left and right thread rolling dies. The structure of the tube expansion processing device is shown in the attached figure. Figure 3-5 As shown, the assembly includes two rollers 11 (left and right), an inner mold 13, a turntable 15, and a water-jetting gun 14. The left and right rollers 11 replace the left and right thread rolling dies of the thread rolling machine. Since the raw material tube 12 is hollow, to avoid flattening the raw material tube 12, the left and right rollers extrude it into the desired finished tube 18, which is supported inside the raw material tube 12 by the inner mold 13. The outer circumference of the rollers 11 is machined with spiral grooves, which correspond to the spiral arch and protrusions on the outer surface of the expanded tube. The outer circumference of the inner mold 13 is machined with spiral protrusions, which correspond to the spiral grooves on the rollers and also to the spiral arch on the inner surface of the expanded tube. The turntable 15 is located in front of the rollers 11. The water-jetting gun 14 is mounted on the turntable 15, and the distance between the nozzle of the water-jetting gun 14 and the turntable 15 is the length of the expanded tube. The rotation center of the turntable 15 coincides with the center of the finished tube 18, that is, with the axis of symmetry of the two rollers 11. This ensures that the distance between the nozzle of the waterjet cutting gun 14 and the outer surface of the finished tube 18 is approximately the same, allowing for smooth cutting. The turntable 15 is fixed and driven to rotate by a rotating shaft 16. The front end of the rotating shaft 16 is machined with a water inlet 17, which connects to high-pressure water outward and to the nozzle of the waterjet cutting gun 14 inward through a water pipe fixed on the turntable 15. Even when the turntable 15 rotates, high-pressure water can still be delivered from the water inlet 17 through the water pipe to the nozzle to complete the cutting of the finished tube 18.

[0024] In this embodiment, the port of the raw material tube 12 is first expanded, and the expanded inner diameter corresponds to the outer diameter of the spiral protrusion of the inner mold. The inner mold 13 is inserted into the raw material tube 12, and its outer circumferential surface is positioned by engaging with the inner wall of the raw material tube 12. Then, the tube opening with the inner mold is inserted between the two rollers 11, and the rollers are started to rotate. The spiral protrusion of the inner mold 13 engages with the spiral groove on the roller 11, and the roller 11 drives the raw material tube 12 and the inner mold 13 to rotate. The engagement of the spiral groove and the spiral protrusion causes the raw material tube to move forward in a spiral shape during rotation, while the inner mold is constrained by the engagement of the rollers and will not move forward with the finished tube, thus preventing slippage between the inner mold and the raw material tube. In this way, under the rotational engagement of the spiral protrusion and the spiral groove, the tube wall of the raw material tube 12 forms an arched and pointed structure. When the finished tube 18 contacts the turntable 15 in front, the two rollers 11 on the left and right stop rotating. Then the turntable 15 rotates, and at the same time, high-pressure water is turned on. The high-pressure water sprayed from the nozzle of the water-jet cutting gun 14 cuts the finished tube 18, making it an expanded tube. After the turntable 15 rotates one revolution and the expanded tube falls, the turntable 15 stops rotating, and the rollers continue to rotate, continuing to squeeze the raw material tube forward to become the finished tube 18. Example 2

[0025] In Example 1, the inner mold is not constrained in the axial direction of rotation; its movement in this direction is limited only by the engagement of the helical protrusion and the helical groove. If this constraint is less than the frictional force between the inner mold and the inner wall of the raw material tube, the helical protrusion will disengage from the helical groove, causing the raw material tube to move upwards and preventing proper extrusion deformation. Extrusion deformation can only be achieved by re-engaging the helical groove and the helical protrusion. Therefore, this embodiment restricts the movement of the inner mold along the axial direction of rotation, as shown in the attached diagram. Figure 6 As shown.

[0026] Turntable 15 is a gear turntable, and shaft 16 is a hollow shaft. The two are rotatably connected by bearing 20. The gear turntable is driven to rotate by drive gear 21. A laser cutting torch 22 is fixedly mounted on turntable 15. The distance between the nozzle of the laser cutting torch 22 and turntable 15 corresponds to the length of the expanded tube and is determined by the component and position that the front end of the finished tube 18 contacts. When the turntable rotates, the laser cutting torch 22 can cut the finished tube 18 as the turntable rotates. Shaft 16 is fixed, and cylinder 19 is fixedly mounted at its front end. Cylinder 19 is set in the center hole of shaft 16, and the cylinder rod end of cylinder is rotatably connected to top block 23.

[0027] In this embodiment, before the roller 11 is activated, the cylinder rod extends into the raw material tube, and the top block 23 at the end of the cylinder rod contacts the inner mold 13. The roller 11 drives the raw material tube 12 and the inner mold 13 to rotate, and the top block 23 rotates accordingly, but the cylinder rod remains stationary. The force of the inner mold 13 moving forward is applied to the top block 23, ensuring the stability of the rotation of the inner mold and the roller. When the finished tube 18 contacts the turntable 15, the roller 11 stops rotating, the drive gear 21 drives the turntable 15 to rotate, and at the same time, the laser cutting gun 22 is energized to cut the finished tube 18 into an expanded tube. The expanded tube falls onto the cylinder rod, the cylinder rod retracts, and the expanded tube falls. Subsequently, the cylinder rod extends and contacts the inner mold to process the next expanded tube. During the extrusion process, the roller, inner mold, and top block rotate. During the cutting process, the drive gear drives the turntable and the cutting gun to rotate. After the cutting, when the expanded tube falls, the cylinder rod extends and retracts. Example 3

[0028] The expansion tube has a thin wall. In Example 1, high-pressure water cutting is used, which has relatively low water pressure and good safety. However, the sprayed water needs to be recycled, and the device and expansion tube are prone to rust. Example 2 replaces this with laser cutting, using a laser cutting head instead of the gun head and a cable instead of the water pipe on the turntable. The laser-cut end face is as flat as the high-pressure water cutting surface, requiring no further processing. However, because laser cutting requires a cable, the turntable rotates clockwise once and then counterclockwise to avoid cable tangling. Care should be taken to check for wear on the cable insulation. Additionally, the high-temperature dust from laser cutting can adhere to the cylinder rod. When the cylinder rod extends or retracts, it can affect the cylinder's sealing. Therefore, it is advisable to protect the cylinder rod, such as by covering it with a flexible tube, or by retracting the cylinder rod before cutting and extending it after the expansion tube descends. This example combines the structures of the turntable mechanisms from the two examples, as shown in the attached diagram. Figure 7 As shown. The rotating shaft 16 drives the turntable 15 to rotate, which in turn drives the laser cutting gun 22 on the turntable to rotate, thereby realizing the cutting of the finished tube 18.

[0029] A rotating shaft 16 is fixedly connected to a push rod 24 in the direction of the inner mold 13. The end of the push rod 24 has an annular hemispherical recess, within which a push ball 25 is placed. The push ball 25 can roll within the recess but does not detach from it. The rotating shaft 16 and its drive mechanism can move as a whole. After laser cutting, the entire assembly moves forward, causing the rotating shaft 16 and push rod 24 to move forward, dropping the cut expansion tube. Then, the entire assembly moves backward, causing the push rod 24 to move backward. After the push ball 25 contacts the inner mold 13, it drives the roller 11 to continue compressing and deforming the raw material tube 12. In this embodiment, no special protection is required for the push rod.

[0030] It should be noted that: 1) Expansion tubes are mostly made of 08 steel or 10 steel, which have low strength and thin walls, making them suitable for cold expansion of the raw material tube opening. 2) To reduce the friction between the inner mold and the inner wall of the raw material tube, lubricating oil or grease is pre-applied to the outer surface of the inner mold. The lubricating oil or grease can be removed in the subsequent galvanizing pickling and alkaline washing processes. 3) To ensure the smooth extrusion deformation of the raw material tube, the inner diameter of the raw material tube corresponds to the outer diameter of the circumference of the inner mold. After entering the roller, the raw material tube only deforms on the surface in contact with the inner mold protrusion and the outer mold groove; other surfaces do not deform. After the raw material tube is fed, the inner mold falls out of the raw material tube, and the next raw material tube is processed. 4) Thread rolling machines are commonly used equipment in fastener manufacturing. This utility model improves upon the thread rolling machine by installing a turntable and cutting torch, etc., so that special equipment is not required. However, this utility model does not deny that special equipment can also be used. 5) The cutting torches in the embodiments are interchangeable. 6) A hydraulic cylinder can also be used instead of a pneumatic cylinder. Because the length and inner diameter of the expansion tube are relatively small, a small pneumatic cylinder is more suitable. A hydraulic cylinder can also be used if a hydraulic power unit is available. In the absence of compressed air and a hydraulic power unit, a screw structure can be used, with a small motor driving the screw to rotate and achieve its extension and retraction. This is an equivalent substitution for a pneumatic or hydraulic cylinder. 7) This invention can also be used for processing steel pipes without protruding tips or spiral arches.

[0031] This invention is an improvement on the thread rolling machine, replacing the thread rolling die with a roller, adding an inner die, and installing a turntable and cutting torch, eliminating the need to design and manufacture specialized equipment. Tube expansion is achieved in one step, with extrusion deformation and cutting performed intermittently and continuously on a single device. Based on automatic control, semi-automatic mass production can be achieved, enabling low-cost production of expanded tubes. Manual labor is only required to insert the inner die into the tube opening and engage the roller.

Claims

1. A tube-expanding apparatus characterized by comprising: It comprises two left and right rollers (11), an inner mold (13), a rotating disc (15) and a cutting gun; the outer circumferential surface of the roller (11) is processed with a spiral groove corresponding to the outer surface of the spiral arch of the pipe expander; the outer circumferential surface of the inner mold (13) is processed with a spiral protrusion corresponding to the inner surface of the spiral arch of the pipe expander; the spiral groove cooperates with the spiral protrusion; the rotating disc (15) is arranged in front of the roller (11), the rotation center of the rotating disc (15) is consistent with the symmetrical axis of the two rollers (11); the cutting gun is installed on the rotating disc (15), and the distance between the nozzle of the cutting gun and the rotating disc (15) corresponds to the length of the pipe expander.

2. A tube-expanding device according to claim 1, characterized in that: The rotating disc (15) is a gear rotating disc driven to rotate by a driving gear, the rotating disc (15) is rotationally connected with a rotating shaft (16) through a bearing, the rotating shaft (16) is processed with a center hole, a cylinder or a hydraulic cylinder is arranged in the center hole, the cylinder rod end of the cylinder or the hydraulic cylinder is rotationally connected with a top block (23), and the top block (23) cooperates with the inner mold (13).

3. The tube-expanding device of claim 1, wherein: The cutting gun is a water cutting gun, the rotating disc (15) is fixed and driven to rotate by the rotating shaft (16), the front end of the rotating shaft (16) is processed with a water inlet (17), and the water inlet (17) is communicated with the water cutting gun through a water pipe fixed on the rotating disc (15).

4. The tube-expanding device of claim 1, wherein: The rotating disc (15) is fixed and driven to rotate by the rotating shaft (16), the rotating shaft (16) is fixedly connected with a jacking rod (24), the end of the jacking rod (24) is processed with an annular hemispherical pit, a top ball (25) is placed in the pit, the top ball (25) rolls in the pit without being separated from the pit, and the top ball (25) cooperates with the inner mold (13).

5. The tube-expanding device of claim 1, wherein: The outer circumferential surface diameter of the inner mold (13) corresponds to the inner diameter of the raw material pipe of the pipe expander.

6. The tube-expanding device of claim 1, wherein: The cutting gun is a laser cutting gun.

7. The tube-expanding device of claim 1, wherein: The pipe expander processing device is improved based on a thread rolling machine.

8. The tube-expanding apparatus of claim 1, wherein: Lubricating oil or grease is applied on the outer surface of the inner mold (13).

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