Square steel tube cold-drawing chuck structure

Abstract

The utility model provides a square steel tube cold-drawing chuck structure which comprises a shaft sleeve, a plurality of jaws, a plurality of connecting plates, a central top block and an inner plug core rod capable of being inserted into a square steel tube, and the shaft sleeve, the central top block and the inner plug core rod are coaxially arranged; the shaft sleeve is fixed at the front end of the cold-drawing trolley, the inner diameter of the shaft sleeve is gradually reduced along the direction of the front end of the shaft sleeve, a plurality of sliding chutes for a plurality of jaws to slide are axially formed in the shaft sleeve, the rear end of the central ejector block is coaxially connected with a piston rod of the clamping oil cylinder, the front end of the central ejector block is connected with the rear end of the inner plug core rod, and the front end of the inner plug core rod extends into the shaft sleeve; and the two ends of one connecting plate are respectively hinged with the central top block and one jaw. A chuck structure is arranged on the cold-drawing trolley, and a piston rod of a clamping oil cylinder on the cold-drawing trolley is controlled to extend or retract to drive a plurality of jaws in a shaft sleeve to obliquely move, so that a square steel pipe is clamped or loosened, the square steel pipe does not need to be subjected to heading treatment before cold drawing, and the metal loss of the square steel pipe can be reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of cold drawing of square steel pipes, in particular to a cold drawing chuck structure of a square steel pipe. Background Art

[0002] At present, before the square steel tube begins cold drawing, it is necessary to press Figure 1 The header treatment shown in the figure helps to stably fix the square steel tube on the cold drawing machine to prevent it from slipping or deviating from the predetermined trajectory during the drawing process. However, this header treatment method adds a processing step to the cold drawing process and causes metal consumption at the header position of the square steel tube. Utility Model Content

[0003] In view of the deficiencies of the prior art, the utility model provides a square steel tube cold drawing chuck structure, which eliminates the need for heading treatment of the square steel tube before cold drawing and can reduce metal loss of the square steel tube.

[0004] The technical solution of the utility model is achieved in this way:

[0005] A square steel tube cold drawing chuck structure, comprising a shaft sleeve, a plurality of jaws, a plurality of connecting plates, a central top block and an inner plug core rod which can be plugged into the square steel tube, wherein the shaft sleeve, the central top block and the inner plug core rod are coaxially arranged;

[0006] The sleeve is fixed at the front end of the cold drawing trolley, and the inner diameter of the sleeve gradually decreases along its front end direction. A plurality of sliding grooves for sliding of a plurality of jaws are axially arranged in the sleeve. A jaw is slidably arranged in a sliding groove. The rear end of the center top block is coaxially connected to the piston rod of the clamping cylinder, and the front end is connected to the rear end of the inner plug core rod. The front end of the inner plug core rod extends into the sleeve. The two ends of a connecting plate are hinged to the center top block and a jaw respectively.

[0007] Preferably, the slide groove is a T-shaped groove, and the jaw comprises a T-shaped body having an inclined top surface.

[0008] Preferably, a plurality of latch teeth are provided on the bottom surface of the T-shaped body.

[0009] Preferably, the center top block includes a hollow cavity running through both ends thereof, the hollow cavity includes a piston rod connecting cavity, a threaded cavity and an insert cavity which are connected in sequence, the piston rod of the clamping cylinder is fixed in the piston rod connecting cavity, a fixing nut is fixed in the threaded cavity, and the rear end of the inner plug core rod passes through the insert cavity and is threadedly connected to the fixing nut.

[0010] Preferably, the jaws further include a hinge block, which is arranged at the rear end of the T-shaped body, and a first hinge hole is provided on the hinge block;

[0011] The central top block includes a plurality of ear plates arranged on the periphery of the main body thereof, and the ear plates are provided with second hinge holes;

[0012] The two ends of the connecting plate are respectively provided with a first through hole and a second through hole;

[0013] The first connecting pin passes through the first hinge hole and the first through hole to hinge the connecting plate with the jaw, and the second connecting pin passes through the second hinge hole and the second through hole to hinge the connecting plate with the central top block.

[0014] Preferably, the first through hole is a waist-shaped hole.

[0015] Preferably, the inner plug core rod includes a rectangular body and a cylinder, the cylinder is arranged at the rear end of the rectangular body, the cylinder is connected to the front end of the center top block, and the outer surface of the rectangular body matches the inner hole of the square steel pipe.

[0016] Preferably, there are four jaws, which are respectively located on the outsides of four side surfaces of the rectangular body.

[0017] Preferably, the front end of the inner plug core rod is tapered.

[0018] Preferably, the rear end of the sleeve extends outward to form a convex portion, and the chuck structure also includes a clamping nut, which is sleeved on the front end of the cold drawing trolley and the rear end of the sleeve, and the inner end face of the clamping nut abuts against the front end face of the convex portion, and the rear end face of the convex portion abuts against the front end face of the cold drawing trolley.

[0019] Compared with the prior art, the beneficial effects of the utility model are:

[0020] A chuck structure is arranged on the cold drawing trolley, and the chuck structure comprises a shaft sleeve, a plurality of jaws, a plurality of connecting plates, a center top block and an inner plug core rod which can be plugged into the inside of the square steel pipe. By controlling the clamping cylinder piston rod fixed on the cold drawing trolley to extend or retract, the plurality of jaws in the shaft sleeve are driven to move obliquely, so that the square steel pipe can be clamped or loosened conveniently. The square steel pipe does not need to be headed before cold drawing, and the square steel pipe has small deformation during clamping and short clamping length, so as to reduce metal loss of the square steel pipe. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a cross-sectional schematic diagram of a square steel pipe headed before cold drawing in the prior art;

[0022] Figure 2 It is a schematic axial cross-sectional view of the clamping and drawing state of the first embodiment of the utility model;

[0023] Figure 3 It is a radial cross-sectional schematic diagram of the clamping and drawing state of the first embodiment of the utility model;

[0024] Figure 4 This is a schematic axial cross-sectional view of a first embodiment of the utility model in a relaxed state;

[0025] Figure 5This is a radial cross-sectional schematic diagram of a first embodiment of the utility model in a relaxed state;

[0026] Figure 6 It is a left side view of the shaft sleeve in the first embodiment of the utility model;

[0027] Figure 7 For along Figure 6 Sectional view along line AA;

[0028] Figure 8 This is a front view of the jaws in the first embodiment of the utility model;

[0029] Fig. 9 It is a right side view of the jaws in the first embodiment of the utility model;

[0030] Fig.10 It is a right side view of the central top block in the first embodiment of the utility model;

[0031] Fig.11 For along Fig.10 Sectional view along the midline BB;

[0032] Fig.12 This is a front view of the inner plug core rod in the first embodiment of the utility model;

[0033] Fig.13 It is a front view of the inner plug core rod in the second embodiment of the utility model.

[0034] Figure ID:

[0035] 1-square steel pipe; 2-sleeve; 21-slide groove; 22-protrusion; 3-jaw; 31-T-shaped body; 32-grip; 33-hinge block; 331-first hinge hole; 5-connecting plate; 51-first through hole; 52-second through hole; 6-center top block; 61-piston rod connecting cavity; 62-screw cavity; 63-insertion cavity; 64-ear plate; 641-second hinge hole; 7-cold drawing trolley; 8-clamping cylinder; 9-inner plug core rod; 91-rectangular body; 92-cylinder; 10-first connecting pin; 11-second connecting pin; 12-fixing nut. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0037] In the description of the present utility model, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0038] Embodiment 1

[0039] See also Figure 2 A square steel tube cold drawing chuck structure, comprising a sleeve 2, a plurality of jaws 3, a plurality of connecting plates 5, a central top block 6 and an inner plugging core rod 9 which can be plugged into the square steel tube 1, wherein the sleeve 2, the central top block 6 and the inner plugging core rod 9 are coaxially arranged;

[0040] The sleeve 2 is fixed at the front end of the cold drawing trolley 7, and the inner diameter of the sleeve 2 gradually decreases along its front end direction. A plurality of slide grooves 21 for sliding of a plurality of jaws 3 are axially arranged in the sleeve 2. One jaw 3 is slidably arranged in a slide groove 21, and the number of slide grooves 21 is the same as that of the jaws 3. The rear end of the center top block 6 is coaxially connected with the piston rod of the clamping cylinder 8, so that the center top block 6 is driven to move when the piston rod of the clamping cylinder 8 is extended or retracted. The front end is connected to the rear end of the inner plug core rod 9, and the front end of the inner plug core rod 9 extends into the sleeve 2. The two ends of a connecting plate 5 are respectively hinged to the center top block 6 and a jaw 3, the front end of the connecting plate 5 is hinged to the jaw 3, and the rear end of the connecting plate 5 is hinged to the center top block 6.

[0041] It should be noted that the "front end" mentioned in the present application is the end where the clamping structure acts, that is, the end closer to the square steel tube 1, and the other end opposite to the "front end" is called the "rear end"; the cold drawing trolley 7 and the clamping cylinder 8 are existing well-known components of the cold drawing machine, and the clamping cylinder 8 is fixed on the cold drawing trolley 7.

[0042] When in use, first extend the square steel tube 1 to be cold-drawn from the front end of the sleeve 2 into the interior of the sleeve 2, so that the inner plug core rod 9 is inserted into the interior of the square steel tube 1 to be cold-drawn, and the plurality of jaws 3 are outside the square steel tube 1 to be cold-drawn, and then start the clamping cylinder 8 to extend its piston rod, driving the central top block 6 to move forward. Under the action of the connecting plate 5, the plurality of jaws 3 slide forward in the plurality of slide grooves 21. Since the inner diameter of the sleeve 2 gradually decreases along its front end direction, the plurality of jaws 3 slide obliquely forward, gradually approach the square steel tube 1 and finally clamp the square steel tube 1. After the head of the square steel tube 1 is clamped and deformed, it contacts with the inner plug core rod 9 to form a reliable clamping force, and normal drawing work can be carried out. See FIG. Figure 2 and Figure 3 After the square steel tube 1 is drawn, the piston rod of the clamping cylinder 8 is retracted, the center top block 6 moves backward, and the connecting plate 5 installed at the front end of the center top block 6 drags a number of jaws 3 to slide backward along the slide groove 21 and releases the clamping of the other steel tube 1. The drawn square steel tube 1 can be taken out from the front end of the sleeve 2, see Figure 4 and Figure 5 .

[0043] It can be seen that the present invention sets a chuck structure on the cold drawing trolley 7, and the chuck structure includes a sleeve 2, a plurality of jaws 3, a plurality of connecting plates 5, a central top block 6 and an inner plug core rod 9 that can be plugged into the inside of the square steel tube 1. By controlling the piston rod of the clamping cylinder 8 fixed on the cold drawing trolley 7 to extend or retract, the plurality of jaws 3 in the sleeve 2 are driven to move obliquely, so as to conveniently realize the clamping or loosening of the square steel tube 1. The square steel tube 1 does not need to be as shown in FIG. Figure 1 As shown, a heading process is added, and the square steel tube 1 has a small clamping deformation and a short clamping length, which can reduce the metal loss in the cold drawing process.

[0044] Among them, see Figures 6 to 9 The slide groove 21 is a T-shaped groove, and the jaw 3 includes a T-shaped body 31. The T-shaped body 31 has an inclined top surface. The inclined top surface of the T-shaped body 31 can adapt to the inclined T-shaped groove in the sleeve 2, so that the jaw 3 can move obliquely.

[0045] Preferably, see Figure 8 In order to increase the friction between the jaws 3 and the square steel tube 1 and make the square steel tube 1 more firmly clamped, the present invention arranges a plurality of clamping teeth 32 on the bottom surface of the T-shaped body 31, and utilizes the clamping teeth 32 to clamp the square steel tube 1 to prevent the square steel tube 1 from sliding during the cold drawing process.

[0046] See also Figure 2 , Fig.10 and Fig.11The center top block 6 includes a hollow cavity that runs through both ends thereof, and the hollow cavity includes a piston rod connecting cavity 61, a screw connection cavity 62, and an insert cavity 63 that are connected in sequence. The piston rod of the clamping cylinder 8 is fixed in the piston rod connecting cavity 61, and a fixing nut 12 is fixed in the screw connection cavity 62. The rear end of the inner plug core rod 9 passes through the insert cavity 63 and is threadedly connected to the fixing nut 12. By setting the hollow cavity, the piston rod of the clamping cylinder 8 and the inner plug core rod 9 are connected to the center top block 6, so that the piston rod of the clamping cylinder 8, the center top block 6, and the inner plug core rod 9 can move simultaneously. Among them, the piston rod of the clamping cylinder 8 can be inserted in the piston rod connecting cavity 61 by interference, or fixedly connected by other structures.

[0047] See also Figure 2 , Figure 3 , Figure 8 , Fig.10 and Fig.11 The jaw 3 also includes a hinge block 33, which is arranged at the rear end of the T-shaped body 31, and a first hinge hole 331 is provided on the hinge block 33; the central top block 6 includes a plurality of ear plates 64 arranged on the outer periphery of the main body, and a second hinge hole 641 is provided on the ear plate 64; the two ends of the connecting plate 5 are respectively provided with a first through hole 51 and a second through hole 52; the first connecting pin 10 passes through the first hinge hole 331 and the first through hole 51 to hinge the connecting plate 5 with the jaw 3, and the second connecting pin 11 passes through the second hinge hole 641 and the second through hole 52 to hinge the connecting plate 5 with the central top block 6. The connecting plate 5 and the two connecting pins (i.e., the first connecting pin 10 and the second connecting pin 11) are used to connect the jaw 3 and the central top block 6, so that when the central top block 6 moves, the jaw 3 is driven to move obliquely along the slide groove 21.

[0048] Preferably, the first through hole 51 is a waist-shaped hole. The waist-shaped hole provides a certain amount of activity space for the hinge block 33 of the jaw 3 and the hinge point of the connecting plate 5, allowing the jaw 3 to deviate to a certain extent, and having higher flexibility.

[0049] See also Figure 2 and Fig.12 The inner plug core rod 9 includes a rectangular body 91 and a cylindrical body 92. The cylindrical body 92 is arranged at the rear end of the rectangular body 91. The cylindrical body 92 is connected to the front end of the center top block 6. The outer surface of the rectangular body 91 matches the inner hole of the square steel pipe 1 so that the rectangular body 91 can be inserted into the inner hole of the square steel pipe 1. The cylindrical body 92 can be provided with an external thread and is threadedly connected with the fixing nut 12.

[0050] Preferably, see Figure 2 , Figure 3 , Figure 5 and Fig.12There are four jaws 3, which are respectively located on the outside of the four sides of the rectangular body 91. After the head of the square steel tube 1 is clamped and deformed by the four jaws 3, it contacts with the inner plug core rod 9 to form a reliable clamping force on the four sides of the steel tube 1, which can stabilize the square steel tube 1.

[0051] Optionally, the number of jaws 3 and connecting plates 5 is the same, one jaw 3 is connected to one connecting plate 5, or one jaw 3 is connected to two connecting plates 5, the two connecting plates 5 are located on both sides of the hinge block 33 of the jaw 3, and the first connecting pin 10 passes through the first through hole 51 of one connecting plate 5, the first hinge hole 331 and the first through hole 51 of the other connecting plate 5 in sequence to hinge the two connecting plates 5 to the jaw 3.

[0052] Preferably, see Fig.12 The front end of the inner plug core rod 9 is tapered, which is convenient for taking out the rear steel pipe from the inner plug core rod 9 after drawing.

[0053] See also Figure 2 , Figure 6 and Figure 7 The rear end of the sleeve 2 extends outward to form a convex portion 22. The chuck structure also includes a clamping nut 4, which is sleeved on the front end of the cold drawing carriage 7 and the rear end of the sleeve 2. The inner end surface of the clamping nut 4 abuts against the front end surface of the convex portion 22, and the rear end surface of the convex portion 22 abuts against the front end surface of the cold drawing carriage 7. The sleeve 2 is compressed and installed on the front end of the cold drawing carriage 7 by the clamping nut 4, which is convenient for installation.

[0054] Embodiment 2

[0055] See also Fig.13 In this embodiment, there are three jaws 3, which are respectively located on the outside of the left side, right side and bottom surface of the rectangular body 91. Compared with the first embodiment, the top surface of the rectangular body 91 of this embodiment is not provided with jaws 3, and the three jaws 3 clamp the left side, right side and bottom surface of the steel pipe 1 respectively. Although the clamping force is slightly weaker than that of the first embodiment, its advantage is that the number of jaws 3 can be reduced, thereby reducing the cost of the square steel pipe cold-drawn chuck structure. In fact, the number of jaws 3 can be set to two, which are respectively located on the outside of the left side and right side of the rectangular body 91, or respectively located on the outside of the top surface and bottom surface of the rectangular body 91. In addition,

[0056] After the head of the square steel pipe 1 is clamped and deformed by the three jaws 3, it contacts the inner plug core rod 9 to form a reliable clamping force on the four sides of the steel pipe 1, which can stabilize the square steel pipe 1. The jaws 3 can also be set in greater numbers, such as six, to increase the clamping force on the steel pipe 1.

[0057] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A square steel tube cold drawing chuck structure, characterized in that: It comprises a shaft sleeve (2), a plurality of jaws (3), a plurality of connecting plates (5), a central top block (6) and an inner plugging core rod (9) which can be plugged into the interior of a square steel pipe (1), wherein the shaft sleeve (2), the central top block (6) and the inner plugging core rod (9) are coaxially arranged; The sleeve (2) is fixed at the front end of the cold drawing trolley (7), and the inner diameter of the sleeve (2) gradually decreases along its front end direction. The sleeve (2) is axially provided with a plurality of slide grooves (21) for sliding a plurality of jaws (3). One jaw (3) is slidably arranged in one of the slide grooves (21). The rear end of the center top block (6) is coaxially connected to the piston rod of the clamping cylinder (8), and the front end is connected to the rear end of the inner plug core rod (9). The front end of the inner plug core rod (9) extends into the sleeve (2). The two ends of a connecting plate (5) are respectively hinged to the center top block (6) and one of the jaws (3).

2. The cold-drawn chuck structure for square steel tube according to claim 1, characterized in that: The slide groove (21) is a T-shaped groove, and the jaw (3) comprises a T-shaped body (31), wherein the T-shaped body (31) has an inclined top surface.

3. The cold-drawn chuck structure for square steel tube according to claim 2, characterized in that: The bottom surface of the T-shaped body (31) is provided with a plurality of latch teeth (32).

4. The cold-drawn chuck structure for square steel tube according to claim 1, characterized in that: The central top block (6) includes a hollow cavity passing through both ends thereof, the hollow cavity including a piston rod connecting cavity (61), a screw connection cavity (62) and an insert cavity (63) which are connected in sequence, the piston rod of the clamping cylinder (8) is fixed in the piston rod connecting cavity (61), a fixing nut (12) is fixed in the screw connection cavity (62), and the rear end of the inner plug core rod (9) passes through the insert cavity (63) and is threadedly connected to the fixing nut (12).

5. The cold-drawn chuck structure for square steel tube according to claim 2, characterized in that: The jaw (3) further comprises a hinge block (33), wherein the hinge block (33) is arranged at the rear end of the T-shaped body (31), and a first hinge hole (331) is provided on the hinge block (33); The central top block (6) comprises a plurality of ear plates (64) arranged on the outer periphery of the main body thereof, and the ear plates (64) are provided with second hinge holes (641); The two ends of the connecting plate (5) are respectively provided with a first through hole (51) and a second through hole (52); The first connecting pin (10) passes through the first hinge hole (331) and the first through hole (51) to enable the connecting plate (5) to be hinged to the jaw (3), and the second connecting pin (11) passes through the second hinge hole (641) and the second through hole (52) to enable the connecting plate (5) to be hinged to the center top block (6).

6. The square steel tube cold drawing chuck structure according to claim 5, characterized in that: The first through hole (51) is a waist-shaped hole.

7. The square steel tube cold drawing chuck structure according to claim 1, characterized in that: The inner plug core rod (9) comprises a rectangular body (91) and a cylinder (92), wherein the cylinder (92) is arranged at the rear end of the rectangular body (91), and the cylinder (92) is connected to the front end of the central top block (6), and the outer surface of the rectangular body (91) matches the inner hole of the square steel pipe (1).

8. The cold-drawn chuck structure for square steel tube according to claim 7, characterized in that: The number of the jaws (3) is four, and the four jaws (3) are respectively located on the outer sides of the four side surfaces of the rectangular body (91).

9. The cold-drawn chuck structure for square steel tube according to any one of claims 1 to 8, characterized in that: The front end of the inner plug core rod (9) is tapered.

10. The cold-drawn chuck structure for square steel tube according to any one of claims 1 to 8, characterized in that: The rear end of the sleeve (2) extends outward to form a convex portion (22), and the chuck structure also includes a clamping nut (4), which is sleeved on the front end of the cold-drawn trolley (7) and the rear end of the sleeve (2), and the inner end surface of the clamping nut (4) abuts against the front end surface of the convex portion (22), and the rear end surface of the convex portion (22) abuts against the front end surface of the cold-drawn trolley (7).

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