CN201186355Y - Fixture for processing flexible long shaft - Google Patents

Abstract

A jig fixture used for machining a flexible long-axis (5) comprises a lathe spindle chuck (1), a tailstock clamping chuck (9), a threaded rod pin (2) and locking nuts (3,7), wherein the tailstock clamping chuck (9) and the lathe spindle chuck (1) always apply the stretching force to the clamped flexible long-axis (5). The jig fixture of the utility model is beneficial for the flexible long-axis whose length-diameter ratio is 40-60 to obtain a good machining accuracy.

Description

Tooling Fixtures for Flexible Long Axis Machining

technical field

The utility model relates to a tooling fixture for processing a flexible long shaft, in particular to a long shaft with a length-to-diameter ratio of 40-60, small circular runout and surface treatment requirements, and belongs to the field of special tooling fixtures.

Background technique

Today, mechanical products are increasingly diversified, and are developing in the direction of high precision and low surface roughness. Shaft parts are widely used in the machinery industry, such as in aerospace, automobiles, printing machinery, small motors and heavy-duty fast transmission devices. Long axis processing is the processing of shaft parts, and it is also a difficult point in machining. According to processing experience, a shaft with a ratio of shaft length to shaft diameter (aspect ratio) of 40-60 is usually called a flexible long shaft, or a slender shaft.

The flexible long axis has great flexibility and poor rigidity. During cutting, the radial deflection of the flexible long axis occurs due to the centrifugal force generated by its own weight. In addition, in the turning process, the processing system composed of the lathe-fixture-tool will also vibrate the processing system. All these factors affect the processing accuracy of the flexible long axis.

The traditional clamping methods for shaft processing are: double center clamping or double chuck clamping. As shown in Figure 1, both of these two clamping methods make the processed shaft in a state of being squeezed by the force F, and the shaft section is prone to bending deformation in the axial direction. This clamping process is only suitable for shafts with small length-to-diameter ratio, short shaft length or large radial runout tolerance of the shaft.

Contents of the invention

In order to prevent the processed flexible long shaft from being squeezed, the utility model proposes a new processing technology and special tooling, so that the processed long shaft is in the state of axial tension and stress, as shown in Figure 2.

For this reason, the utility model adopts "stretching clamping" by improving the original "traditional shaft processing fixture-double top clamping or double chuck type clamping" mode. That is: one end of the flexible long axis is fixed on the spindle end of the machine tool, and the other end is in a clamping (clamping) state with a certain tension.

The tooling fixture of the present utility model is shown in Figure 3. One end of the flexible long axis is fixed on the machine tool spindle chuck 1, and the other end is clamped by the tailstock clamping chuck 9 on the special tooling fixed on the lathe tailstock. The processed flexible long axis 5 is always in a "stretched" state during processing.

For easy clamping, both ends of the flexible long shaft are machined with central threaded holes, such as C-type. The ratio of threaded hole diameter to shaft outer diameter is about 1:2.

Generally, the circular runout and surface treatment requirements of flexible long shafts are higher than those of ordinary shafts. Therefore, when processing such a flexible long shaft, not only the clamping method, but also the coordination between the clamping force and the processing technology must be considered. If the double-head clamping process is used, it is suitable for shafts with an aspect ratio of 20-30 and a circular runout of 0.25-0.35. This is because the clamped point of the shaft is not at the same position (place) for each clamping between processes. If the processing requirements of the flexible long shaft are high, this double-head clamping process is no longer an ideal process solution.

The two ends of the flexible long shaft are respectively machined with central threaded holes (C type), and the clamping force point is at the same position. Therefore, this positioning process has high benchmarking and good stability, and is suitable for processing flexible long axes with high precision.

During processing, one end of the flexible long shaft is first fixed to the jaw plate and clamped, and the other end is clamped by a special tool, which is fixed on the tailstock of the lathe.

At the end connected with the lathe tailstock, process the central threaded hole (type C) of the flexible long axis.

Homemade threaded pin rod. Slot the bare rod end of the threaded pin rod. This can be tightened or loosened by a screwdriver to achieve the purpose of loading and unloading.

The thread of the central hole of the flexible long shaft end is connected with the threaded section of the threaded pin rod, and the retaining ring is interposed between the flexible long shaft end and the nut. The nuts (two) are screwed in opposite directions and fixed, so that the retaining ring "tightens" the shaft and plays a locking role. The tailstock clamping chuck claw on the tailstock blocks the polished rod end of the threaded pin rod.

The inner diameter of the bearing is closely matched with the outer diameter of the pointed cone on the tailstock of the lathe. In this way, the inner diameter of the bearing is fixed on the tapered end face of the lathe. The outer diameter of the bearing is closely matched with the bearing chamber of the flange, and is embedded in the bearing chamber of the flange. The top plate is fixed with screws so that the bearing is in a fixed state without offset. Subsequently, the tailstock tailstock of the lathe is moved to the right and locked, so that the flexible long axis is in a "horizontally straightened" state as a whole.

Through the flexible long axis stretching tooling and clamping, the flexible long axis with an aspect ratio of 40-60 is in a "horizontally straightened" state as a whole. This is conducive to obtaining good machining accuracy. After testing, the processed flexible long axis meets the design requirements.

The flexible long shaft requires surface treatment: nickel plating, nickel phosphorus plating, nitriding, nitrogen oxide, etc. After the tooling is installed on the tailstock of the lathe, it does not need to be moved. It does not affect the processing of other similar processes. Threaded central holes are processed at both ends of the flexible long shaft. The central hole can also be called a process hole (removed after being processed to size), so the special tooling can process the rough, medium and fine processes of the long shaft respectively. If the diameter of the flexible long axis to be processed is not greater than the maximum opening distance of the jaws and the axis length is not greater than the effective stroke of the turning tool, the flexible long axis can be processed by installing this type of tooling.

Flexible long-axis stretching tooling can realize batch processing, improve production efficiency and reduce costs. The flexible long-axis stretching tooling is suitable for installation on lathes with larger spindle chuck diameters and larger turning tool strokes.

The tooling of the utility model can be widely used in the field of machinery manufacturing, such as aerospace, automobile, printing machinery, small motors and light-load fast transmission devices.

Description of drawings

Fig. 1 is a schematic diagram of the compression state of the flexible long axis during processing on the existing tooling;

Fig. 2 is to be realized by the utility model, a schematic diagram of the stretched state of the flexible long axis during processing;

Fig. 3 is a schematic diagram of the stretching process clamping of the flexible long axis on the tooling of the utility model;

In the specific embodiment of the utility model in Fig. 4, the schematic diagram of lathe processing flexible long axis and tooling clamping;

In the specific embodiment of the utility model in Fig. 5, the structural diagram of the flange in the fixture;

In the specific embodiment of the utility model in Fig. 6, the structural diagram of the top plate in the fixture;

In the specific embodiment of the utility model in Fig. 7, the structural diagram of the threaded rod pin in the fixture;

Fig. 8 is a schematic diagram of the clamping of the spindle end of the flexible long-axis stretching tooling lathe in a specific embodiment of the utility model;

Fig. 9 is a schematic diagram of the clamping of the tailstock of the flexible long-axis stretching tooling lathe in a specific embodiment of the utility model;

Fig. 10 is a schematic diagram of assembly and clamping of the tailstock of the flexible long-axis stretching tooling lathe in a specific embodiment of the utility model.

Detailed ways

As shown in FIG. 4 , the processed flexible long axis 5 is clamped between the lathe spindle chuck 1 and the tailstock clamping chuck 9 . After clamping, the machine tool has in sequence: lathe spindle chuck 1, threaded rod pin 2, two lock nuts 3, retaining ring 4, processed flexible long axis 5, retaining ring 6, two lock nuts 7, Threaded rod pin 8, tailstock clamping chuck 9, flange plate 10, bearing 11, top plate 12.

Wherein, the structure of flange plate 10 is shown in Figure 5, is the hollow entity that big cylinder and small cylinder constitute, end has bearing chamber, has a plurality of threaded holes on it, is used for clamping chuck 9, tailstock and tailstock. Connection of top plate 12.

Wherein, the structure of the top plate 12 is shown in FIG. 6 , similar to the flange plate 10 , it is also a hollow entity composed of a large cylinder and a small cylinder, and has a plurality of threaded holes on it.

The structure of threaded rod pin 2/7 is shown in Figure 7, and one end has external thread, and the other end head is cotter pin.

As shown in FIG. 8 , one end of the processed flexible long shaft 5 has a central threaded process hole. One end of the threaded rod pin 2 is screwed into the hole of the flexible long shaft 5, and the other end of the polished rod is inserted into the lathe spindle chuck 1. The two nuts 3 are sleeved on the threaded rod pin 2, and they are opposite to each other, so as to lock the retaining ring 4 on the end surface of the flexible long shaft 5.

As shown in FIG. 9 , the other end of the processed flexible long shaft 5 has a central threaded process hole. The threaded rod pin 6 has one end screwed into the hole of the flexible long shaft 5, and inserts the tailstock clamping chuck 9 for the other end of the polished rod. Two nuts 7 are sleeved on the threaded rod pin 6, and they are opposite to each other, so as to lock the retaining ring 6 on the end face of the flexible long shaft 5.

As shown in FIG. 10 , the inner diameter of the bearing 11 is sleeved on the cylindrical side of the top cone 14 of the lathe tailstock, and the outer diameter of the bearing 11 is closely matched with the bearing chamber of the flange 10 . Through screws 15 , the top plate 12 is fixedly connected to the flange 10 and axially positioned to the bearing 11 . Through screws 13, the flange 10 is fixedly coupled to the tailstock holding chuck 9.

Claims (5)

1. A fixture for flexible long-axis processing, comprising a lathe spindle chuck (1), a tailstock clamping chuck (9), characterized in that: the fixture also includes a threaded rod pin (2), a lock Tighten nuts (3, 7); the end of the above-mentioned flexible long shaft (5) has a central hole; the threaded rod pin (2) is located between the tailstock clamping chuck (9) and the flexible long shaft (5), and one end is inserted into the tailstock The frame clamps the chuck (9), and the other end is inserted into the center hole of the flexible long shaft (5); the threaded rod pin (2) is also located between the lathe spindle chuck (1) and the flexible long shaft (5), and one end is inserted into the lathe spindle The other end of the chuck (1) is inserted into the central hole of the flexible long shaft (5); the above-mentioned tailstock clamps the chuck (9) and the lathe spindle chuck (1) always exerts a pulling force on the clamped flexible long shaft (5) . 2. The fixture for processing the flexible long shaft according to claim 1, characterized in that the ratio of the diameter of the central threaded hole at the end of the flexible long shaft (5) to the outer diameter of the flexible long shaft (5) is 1:2; one end of the threaded rod pin (2) is a screw rod with external threads, the other end is a polished rod, and the polished rod end is slotted; the screw rod of the threaded rod pin (2) and the internal threaded hole of the flexible long axis (5) are A pair of threaded couplings. 3. The tooling fixture for flexible long-axis processing according to claim 2, characterized in that: the tooling fixture also has a flange (10) and a top plate (12); the top plate (12) is connected to the flange (10) ) is fixedly connected through screws (15); the flange (10) is fixedly connected to the tailstock clamping chuck (9) through screws (13). 4. The tooling fixture for flexible long-axis processing according to claim 3, characterized in that: the above-mentioned flange (10) has a bearing chamber; the bearing (11) is installed on the bearing of the flange (10) In the chamber, the inner diameter of the bearing (11) is sleeved on the cylindrical side of the top cone (14) of the lathe tailstock, and the outer diameter of the bearing (11) is closely matched with the outer wall of the bearing chamber of the flange (10); the top plate (12) is placed on the flange The disc (10) is positioned axially against the bearing (11). 5. The tooling fixture for flexible long shaft processing according to claim 2, characterized in that: the lock nuts (3, 7) on each side of the flexible long shaft (5) are two oppositely locked ; There are retaining rings (4, 6) between the lock nuts (3, 7) and the flexible long shaft (5).

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