Countersunk bolt machining cold header

Abstract

The utility model relates to the technical field of bolt machining, in particular to a cold header for machining countersunk bolts. The countersunk bolt machining cold header comprises a base, a mold is fixedly installed on the base, the base communicates with the bottom of the mold, a bearing ring is fixedly embedded in the bottom of the mold, an annular wrinkled air bag is fixedly installed on the bearing ring, a drawing bar is erected on the annular wrinkled air bag, an integrally-formed protruding part is arranged on the top of the drawing bar, and a pressing plate is fixedly installed on the protruding part. The protruding part is located at the tail end of the threaded section in an aligned mode, and a press-fit air bag used for extruding the stripping rod is further installed in the mold. According to the countersunk bolt machining cold header, through the linkage design of the annular fold air bag and the press-fit air bag, the press-fit air bag expands during inflation to generate damping, the demolding impact force is counteracted, the integrity of a workpiece is protected, the inner diameter of the protruding part at the top of the drawing bar is increased gradually, the protruding part is matched with the tail end of the threaded section, and it is guaranteed that the workpiece is accurately formed in the cold heading last stage.

Description

Technical Field

[0001] This utility model relates to the field of bolt processing technology, and in particular to a cold heading machine for countersunk bolt processing. Background Technology

[0002] A cold heading machine is a forging device that thickens the top of bars or wires at room temperature. It is mainly used to manufacture bolts, screws, and other parts. By using cold heading to forge the heads of bolts and screws, minimal or no cutting is required, allowing them to be directly formed into the desired shape and size. This not only saves a significant amount of material but also greatly improves production efficiency and significantly enhances the mechanical strength of the forged parts.

[0003] Currently, in the forming of bolt ends, after the interaction between the punch and the die is completed, the workpiece is basically ejected by the action of compressed air, which separates the workpiece from the die. Under the impact of the compressed air, the workpiece leaves the die with a large kinetic energy, which can easily lead to excessive instantaneous force when the workpiece is ejected, causing workpiece deformation or thread damage.

[0004] Therefore, it is necessary to provide a new cold heading machine for countersunk bolts to solve the above-mentioned technical problems. Utility Model Content

[0005] To solve the above-mentioned technical problems, this utility model provides a cold heading machine for countersunk bolt processing.

[0006] The countersunk bolt cold heading machine provided by this utility model includes a base, on which a mold is fixedly installed, and the base and the bottom of the mold are interconnected. The upper cylinder wall of the mold is provided with a threaded section for processing steel bars into bolts.

[0007] The bottom of the mold is fixedly fitted with a bearing ring, and an annular pleated airbag is fixedly installed on the bearing ring. A mold-lifting rod is mounted on the annular pleated airbag, and an integrally formed protrusion is provided on the top of the mold-lifting rod. The protrusion is located at the end of the threaded section and aligned. A pressing airbag for extruding the mold-lifting rod is also installed inside the mold.

[0008] The bottom of the base is fixedly connected to an inflation tube for inflating the mold.

[0009] Preferably, an annular groove is formed on the inner wall of the mold below the threaded section, the pressing airbag is installed in the annular groove, and the pressing airbag is connected to the annular pleated airbag through an air guide pipe.

[0010] Preferably, the outer wall of the compression airbag is fixedly connected to the inner wall of the annular groove.

[0011] Preferably, the mold-raising rod is located below the threaded section.

[0012] Preferably, a gasket is fixedly installed on the upper surface of the annular pleated airbag.

[0013] Preferably, the bottom of the mold-forming rod is fixedly connected to the washer.

[0014] Preferably, the inner diameter of the protrusion increases from top to bottom.

[0015] Compared with related technologies, the cold heading machine for countersunk bolts provided by this utility model has the following advantages:

[0016] This invention utilizes a linkage design between annular pleated airbags and compression airbags. When inflated, the compression airbags expand to generate damping, which counteracts the demolding impact force and protects the integrity of the workpiece. Meanwhile, the inner diameter of the protrusion at the top of the mold release bar increases and matches the end of the threaded section, ensuring precise forming of the workpiece at the end of the cold heading process. Attached Figure Description

[0017] Figure 1 A schematic diagram of a preferred embodiment of the cold heading machine for countersunk bolts provided by this utility model;

[0018] Figure 2 for Figure 1 The diagram shows a cross-sectional view of the mold.

[0019] The following are the labels in the diagram: 1. Base; 11. Air pipe; 2. Mold; 2a. Annular groove; 21. Threaded section; 22. Bearing ring; 3. Annular pleated airbag; 4. Mold release rod; 41. Washer; 42. Protrusion; 5. Pressing airbag; 3-5. Air guide pipe. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0021] The specific implementation of this utility model will be described in detail below with reference to specific embodiments.

[0022] Please see Figures 1 to 2This utility model provides a cold heading machine for countersunk bolts. The cold heading machine includes a base 1 and a mold 2. The mold 2 is fixedly installed on the base 1, and the bottom of the base 1 and the mold 2 are interconnected. The upper cylinder wall of the mold 2 is provided with a threaded section 21 for forming a steel bar into a bolt. The bottom of the base 1 is fixedly connected to an air-increasing pipe 11 for inflating the mold 2. When the base 1 is installed on the cold heading machine, the punch moves into the mold 2, causing the workpiece to undergo plastic deformation under the mutual extrusion of the punch and the threaded section 21 in the mold 2, i.e., upsetting. After forming, the punch is withdrawn, and the air-increasing pipe 11 is fixedly connected to the output end of the compressor.

[0023] In the embodiments of this utility model, please refer to Figure 1 and Figure 2 A bearing ring 22 is fixedly fitted to the bottom of the mold 2, and an annular pleated airbag 3 is fixedly installed on the bearing ring 22. A mold-lifting rod 4 is mounted on the annular pleated airbag 3. The mold-lifting rod 4 is located below the threaded section 21, and an integrally formed protrusion 42 is provided on the top of the mold-lifting rod 4. The protrusion 42 is aligned with the end of the threaded section 21, and the inner diameter of the protrusion 42 increases from top to bottom. A pressing airbag 5 for extruding the mold-lifting rod 4 is also installed in the mold 2. Specifically, an annular groove 2a is opened on the inner wall of the mold 2 below the threaded section 21, and the pressing airbag 5 is installed in the annular groove 2a. The pressing airbag 5 is connected to the annular pleated airbag 3 through the air guide pipe 3-5.

[0024] It should be noted that when the punch enters the mold 2 and contacts the protrusion 42, as the punching continues, the protrusion 42 drives the die-setting rod 4 to press down on the annular pleated airbag 3. As a result, the gas in the annular pleated airbag 3 flows into the pressing airbag 5. The expanded pressing airbag 5 presses down on the die-setting rod 4, which has a damping effect. At this time, the workpiece is cold-forged and the punch is withdrawn after the forging is completed. Then, the compressor is turned on so that the airflow pushes the die-setting rod 4 up from the bottom. As a result, the die-setting rod 4 withdraws the workpiece from the mold 2. Because the die-setting rod 4 is damped by the pressing airbag 5, the impact force of the workpiece withdrawing from the mold 2 is reduced, eliminating the impact force when the workpiece is withdrawn by the compressor in the traditional way.

[0025] In this embodiment, since the protrusion 42 is located at the end of the threaded section 21, the workpiece abuts against the protrusion 42 at the end of the cold heading.

[0026] Furthermore, the outer wall of the compression airbag 5 is fixedly connected to the inner wall of the annular groove 2a, so that the compression airbag 5 can expand laterally after being inflated.

[0027] Furthermore, a washer 41 is fixedly installed on the upper surface of the annular pleated airbag 3, and the bottom of the mold release rod 4 is fixedly connected to the washer 41, so that the mold release rod 4 can quickly press the annular pleated airbag 3, while also avoiding damage to the annular pleated airbag 3 by the mold release rod 4.

[0028] In this application, through the linkage design of the annular pleated airbag 3 and the compression airbag 5, the compression airbag 5 expands and generates damping when inflated, which offsets the demolding impact force and protects the integrity of the workpiece. Meanwhile, the inner diameter of the protrusion 42 at the top of the mold release bar 4 increases and matches the end of the threaded section 21, ensuring accurate forming of the workpiece at the end of the cold heading.

[0029] To address the potential aging of the annular pleated airbag 3 or the compressed airbag 5 due to long-term high-frequency inflation and deflation, this solution employs highly elastic, fatigue-resistant composite materials (such as fluororubber) to manufacture the airbag and optimizes the pleated structure to disperse stress.

[0030] The circuits and controls involved in this utility model are all existing technologies, and will not be described in detail here.

[0031] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent structural or procedural transformations made based on the content of this utility model specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A cold heading machine for countersunk bolts, comprising a base (1), on which a mold (2) is fixedly mounted, and the bottoms of the base (1) and the mold (2) are interconnected, wherein the upper cylindrical wall of the mold (2) is provided with a threaded section (21) for forming a steel bar into a bolt, characterized in that: The bottom of the mold (2) is fixedly fitted with a bearing ring (22), and an annular pleated airbag (3) is fixedly installed on the bearing ring (22). A mold release rod (4) is mounted on the annular pleated airbag (3), and an integrally formed protrusion (42) is provided on the top of the mold release rod (4). The protrusion (42) is located at the end of the threaded section (21). A pressing airbag (5) for extruding the mold release rod (4) is also installed inside the mold (2). The bottom of the base (1) is fixedly connected to an air-increasing pipe (11) for inflating the mold (2).

2. The cold heading machine for countersunk bolts according to claim 1, characterized in that, An annular groove (2a) is provided on the inner wall of the mold (2) below the threaded section (21). The compression airbag (5) is installed in the annular groove (2a) and the compression airbag (5) is connected to the annular pleated airbag (3) through the air guide pipe (3-5).

3. The cold heading machine for countersunk bolts according to claim 2, characterized in that, The outer wall of the compressed airbag (5) is fixedly connected to the inner wall of the annular groove (2a).

4. The cold heading machine for countersunk bolts according to claim 1, characterized in that, The mold release bar (4) is located below the threaded section (21).

5. The cold heading machine for countersunk bolts according to claim 4, characterized in that, A gasket (41) is fixedly installed on the upper surface of the annular pleated airbag (3).

6. The cold heading machine for countersunk bolts according to claim 5, characterized in that, The bottom of the mold-raising rod (4) is fixedly connected to the washer (41).

7. The cold heading machine for countersunk bolts according to claim 6, characterized in that, The inner diameter of the protrusion (42) increases from top to bottom.

Images