Pneumatic thread internal expansion type clamp

Abstract

The utility model belongs to the technical field of precision part machining, and relates to a pneumatic thread internal expansion type clamp, which comprises an air bag and a conical expansion sleeve, a conical mandrel is movably connected in the conical expansion sleeve, and the conical mandrel is driven by a pull rod to enable external threads of the conical expansion sleeve to be tightly attached to internal threads of a workpiece. When a gap is formed between the external thread of the conical expansion sleeve and the internal thread of the workpiece, the workpiece can be easily taken down, so that the safety risk caused by removing the door electric linkage rotating main shaft and knocking to disassemble the workpiece in the conventional integral tool is solved, an operator obtains the maximum safety guarantee in the production and manufacturing process, the machining quality of parts is improved, and the production efficiency is improved. The loading and unloading difficulty is improved, and the labor intensity of an operator is reduced.

Description

Technical Field

[0001] This utility model belongs to the field of precision parts processing technology and relates to a pneumatic threaded internal expansion clamp. Background Technology

[0002] With the rapid development of intelligent and information-based technologies, the external shapes of parts are becoming increasingly complex, with more and more thin-walled products, curved surfaces, spheres, and irregularly shaped parts. This places stringent requirements on machining tooling. For thin-walled rotating parts, problems such as tool vibration and slippage are prone to occur when using external clamping, thus affecting machining efficiency and product quality.

[0003] A Chinese invention patent with publication number CN105458318A describes an internal expansion fixture for lathe turning, comprising a fixture body, a fixture tie rod, and expansion blocks. The fixture body has an axially formed inner hole. The fixture tie rod is fitted into the inner hole of the fixture body, and a threaded hole is formed at the lower end of the fixture tie rod, which is threaded to the lathe spindle tie rod. The lathe spindle tie rod pulls the fixture tie rod to move axially within the inner hole of the fixture body. Several expansion block positions are formed on the wall of the fixture body, and expansion blocks are fitted into these positions. The expansion blocks are in frictional contact with the fixture tie rod. When the fixture tie rod moves axially, the friction between the fixture tie rod and the expansion blocks causes the fixture tie rod to push the expansion blocks to move radially, thereby loosening or tightening the product.

[0004] The existing technology has the following technical defects:

[0005] The above technical solution is applicable to parts with curved or inclined surfaces and threaded inner holes that cannot be clamped. In such cases, the inner hole thread needs to be machined first, and then the outer shape is machined using the inner hole thread as a positioning reference. For such parts, a threaded mandrel is used for positioning and clamping. Due to the cutting force, the workpiece becomes increasingly tight during the machining process. When disassembling the workpiece, the door interlock needs to be canceled, the spindle needs to be reversed, and a wooden stick needs to be used to knock the workpiece to loosen it. This results in high labor intensity for workers and poses safety risks. Utility Model Content

[0006] The technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a pneumatic threaded internal expansion clamp.

[0007] The pneumatic threaded internal expansion clamp of this utility model includes an air chamber and a conical expansion sleeve, with a conical mandrel movably connected inside the conical expansion sleeve; the conical expansion sleeve includes an expansion sleeve and a cone, which are fixedly connected, and the expansion sleeve has several expansion grooves, a threaded section at the end of the expansion sleeve, and an expansion cavity inside the expansion sleeve; the conical mandrel includes a conical expansion head, a stop block, and a shaft, the shaft being connected to a movable part inside the air chamber, and the stop block being located inside the expansion cavity.

[0008] Working process or working principle:

[0009] When clamping the workpiece, manually tighten it onto the threaded section of the expansion sleeve. The air compressor drives the shaft to move, causing the tapered expansion head to move into the expansion cavity of the expansion sleeve. The external thread of the expansion sleeve threaded section fits tightly with the internal thread of the workpiece, thus achieving clamping. When disassembling the workpiece, the air compressor drives the shaft to reset, and the tapered expansion head moves outward, creating a gap between the external thread of the expansion sleeve threaded section and the internal thread of the workpiece, allowing the workpiece to be easily removed.

[0010] Each expansion groove is located in the middle of the expansion sleeve and extends to the end of the threaded section. The one-way expansion groove will only cause the threaded section to expand, and will not cause the two ends of the expansion sleeve to expand as a whole.

[0011] The expansion sleeve and the cone are integrally formed.

[0012] The conical expansion head, stop block, and shaft are integrally formed.

[0013] The shaft is connected to the air receiver via a tie rod. One end of the tie rod is fixedly connected to a movable part inside the air receiver, and the other end of the tie rod is threaded to the shaft. The tie rod allows the connection length between the air receiver and the shaft to be adapted to various equipment.

[0014] The air bag is connected to a connector, and the pull rod passes through the connector and is connected to the shaft.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] This invention uses a pull rod to drive a tapered mandrel, causing the external thread of the tapered expansion sleeve to fit tightly with the internal thread of the workpiece. When disassembling the workpiece, the tapered mandrel is released, creating a gap between the external thread of the tapered expansion sleeve and the internal thread of the workpiece, allowing the workpiece to be easily removed. This solves the safety risks associated with previous integrated tooling systems that required disengaging the door interlock to rotate the spindle and disassembling the workpiece by hammering. It provides maximum safety for operators during the manufacturing process, improves the processing quality of parts, reduces the difficulty of loading and unloading, and lowers the labor intensity of operators. Attached Figure Description

[0017] Figure 1 This is a structural schematic diagram of an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the assembly process according to an embodiment of the present invention.

[0019] In the diagram: 1. Workpiece; 2. Conical expansion head; 3. Stop block; 4. Shaft; 5. Threaded section; 6. Expansion groove; 7. Expansion sleeve; 8. Cone; 9. Tie rod; 10. Connecting part; 11. Air chamber. Detailed Implementation

[0020] Example 1

[0021] like Figures 1-2 As shown, the pneumatic threaded internal expansion clamp of this utility model includes an air chamber 11 and a conical expansion sleeve 7, with a conical mandrel movably connected inside the conical expansion sleeve 7; the conical expansion sleeve 7 includes an expansion sleeve 7 and a cone 8, which are fixedly connected; the expansion sleeve 7 has several expansion grooves 6, and a threaded section 5 is provided at the end of the expansion sleeve 7; an expansion cavity is provided inside the expansion sleeve 7; the conical mandrel includes a conical expansion head 2, a stop block 3, and a shaft 4; the shaft 4 is connected to a movable part inside the air chamber 11, and the stop block 3 is located inside the expansion cavity; each expansion groove 6 extends from the middle of the expansion sleeve 7 to the end of the threaded section 5. The unidirectional expansion groove 6 only causes the threaded section 5 to expand, and does not cause the expansion sleeve 7 to expand as a whole at both ends; the expansion sleeve 7 and the cone 8 are integrally formed; the conical expansion head 2, the stop block 3 and the shaft 4 are integrally formed; the shaft 4 is connected to the air chamber 11 through the pull rod 9, one end of the pull rod 9 is fixedly connected to the movable part inside the air chamber 11, and the other end of the pull rod 9 is threadedly connected to the shaft 4. The connection length between the air chamber 11 and the shaft 4 can be adapted to various equipment through the pull rod 9; the air chamber 11 is connected to the connector 10, and the pull rod 9 passes through the connector 10 and is connected to the shaft 4.

[0022] Working process or working principle:

[0023] When clamping workpiece 1, workpiece 1 is manually tightened onto the threaded section 5 of the expansion sleeve 7. The air compressor 11 drives the shaft 4 to move via the pull rod 9, thereby causing the conical expansion head 2 to move into the expansion cavity of the expansion sleeve 7. The external thread of the threaded section 5 of the expansion sleeve 7 is tightly engaged with the internal thread of the workpiece 1, thus achieving clamping. When disassembling workpiece 1, the air compressor 11 drives the shaft 4 to reset, and the conical expansion head 2 moves outward, thereby creating a gap between the external thread of the threaded section 5 of the expansion sleeve 7 and the internal thread of the workpiece 1, allowing workpiece 1 to be easily removed.

[0024] This utility model uses a pull rod 9 to drive a tapered mandrel, causing the external thread of the tapered expansion sleeve 7 to fit tightly with the internal thread of the workpiece 1. When disassembling the workpiece 1, the tapered mandrel is released, and a gap appears between the external thread of the tapered expansion sleeve 7 and the internal thread of the workpiece 1, allowing the workpiece 1 to be easily removed. This solves the safety risks associated with previous integrated tooling systems that required disengaging the door interlock to rotate the spindle and disassembling the workpiece 1 by hammering. It provides maximum safety for operators during the manufacturing process, improves the processing quality of parts, reduces the difficulty of loading and unloading, and lowers the labor intensity of operators.

[0025] The descriptions of the orientation and relative positional relationships of the structure in this utility model, such as descriptions of front, back, left, right, up, and down, do not constitute a limitation on this utility model, but are merely for the convenience of description.

Claims

1. A pneumatic threaded internal expansion clamp, characterized in that: It includes an air bag (11) and a conical expansion sleeve, with a conical mandrel movably connected inside the conical expansion sleeve; The conical expansion sleeve includes an expansion sleeve (7) and a cone (8), which are fixedly connected. The expansion sleeve (7) has several expansion grooves (6), and the end of the expansion sleeve (7) is provided with a threaded section (5). An expansion cavity is provided inside the expansion sleeve (7). The conical mandrel includes a conical expansion head (2), a stop block (3) and a shaft (4). The shaft (4) is connected to the movable part inside the air bag (11), and the stop block (3) is located inside the expansion cavity.

2. The pneumatic threaded internal expansion clamp according to claim 1, characterized in that: Each expansion groove (6) is opened from the middle of the expansion sleeve (7) to the end of the threaded section (5).

3. The pneumatic threaded internal expansion clamp according to claim 2, characterized in that: The expansion sleeve (7) and the cone (8) are integrally formed.

4. The pneumatic threaded internal expansion clamp according to claim 3, characterized in that: The conical expansion head (2), the stop block (3) and the shaft (4) are integrally formed.

5. The pneumatic threaded internal expansion clamp according to any one of claims 1-4, characterized in that: The shaft (4) is connected to the air bag (11) via a pull rod (9). One end of the pull rod (9) is fixedly connected to the movable part inside the air bag (11), and the other end of the pull rod (9) is threadedly connected to the shaft (4).

6. The pneumatic threaded internal expansion clamp according to claim 5, characterized in that: The air bag (11) is connected to a connector (10), and the pull rod (9) passes through the connector (10) and is connected to the shaft (4).

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