A follow rest for machining of carbon-carbon composite elongated screw rod

Abstract

This utility model relates to the field of follower tool technology, specifically disclosing a follower tool for machining slender screws made of carbon-carbon composite materials. It includes a base, with a support plate at the upper end of the base. An adjusting block runs through the support plate, and a rotatable support inner sleeve is provided inside the adjusting block. The support inner sleeve has a support hole in its center for supporting the slender screw, with rounded corners at both ends. This utility model, through a support inner sleeve that rotates synchronously with the workpiece, transforms the direct sliding friction between the traditional follower tool and the workpiece surface into a relatively rolling motion with extremely low resistance between the support inner sleeve and the workpiece. This fundamentally eliminates thread breakage, surface scratches, and grinding damage caused by excessive friction, solving the industry problem of easy breakage and surface damage in the machining of slender screws made of carbon-carbon composite materials. It not only significantly improves the processing quality and yield rate of the product but also enhances processing efficiency and equipment versatility, while ensuring processing stability.

Description

Technical Field

[0001] This utility model relates to the field of follow tool holder technology, specifically a follow tool holder for machining slender screws made of carbon-carbon composite materials. Background Technology

[0002] A follow post is an auxiliary device used in lathe machining to radially support a rotating workpiece, primarily used in machining slender shaft parts (such as guide rods and lead screws). This device dynamically follows the movement of the cutting tool, providing continuous radial support to counteract cutting forces and prevent bending deformation and vibration of the workpiece due to an excessively large length-to-diameter ratio, thereby improving machining accuracy and surface quality.

[0003] When machining slender shafts from carbon-carbon composite (CC) materials, breakage is common, especially for slender screws of M6x1000mm, which are low in strength and brittle. Therefore, a follower tool holder is essential for machining slender screws made of carbon-carbon composite materials. Patent CN104128807B discloses a specially designed follower tool holder for machining slender shafts, comprising a base, a column, and a support block; both the base and support block are connected to the column; the support block has a through-hole clamping hole; the clamping hole supports the workpiece, effectively reducing the radial cutting force on the slender shaft and improving the rigidity of the machine tool and machining process. However, due to the material properties of slender screws made of carbon-carbon composite materials, they are more prone to breakage and damage than other slender shaft parts. Therefore, when using the follower tool holder disclosed in the above patent, the movement of the follower tool holder along the slender screw can easily cause chipping of the threads on the surface of the slender screw, and the sliding resistance between the follower tool holder and the slender screw is relatively large, easily causing surface wear or breakage of the slender screw. Utility Model Content

[0004] This invention addresses the aforementioned shortcomings of existing technologies by providing a follower tool holder for machining slender carbon-carbon composite screws. It solves the industry problem of easy breakage and surface damage during machining of slender carbon-carbon composite screws. This significantly improves product machining quality (reducing chipping, scratches, and breakage) and yield, while also enhancing machining efficiency and equipment versatility, and ensuring machining stability. To achieve the above objectives, this utility model provides the following technical solution: A follower tool holder for machining slender screws made of carbon-carbon composite materials includes a base, a support plate at the upper end of the base, an adjusting block through the support plate, a rotatable support inner sleeve inside the adjusting block, a support hole for supporting the slender screw in the middle of the support inner sleeve, and rounded corners at both ends of the support hole.

[0005] Preferably, the lower end of the support plate is provided with ear plates on both sides, and the ear plates are connected to the base by bolts. The ear plates are provided with elongated second adjustment holes that cooperate with the bolts. Preferably, the support plate is provided with a clearance hole that cooperates with the adjusting block, and positioning grooves are provided on both sides of the clearance hole. The two ends of the adjusting block are connected to the positioning grooves by bolts, and the positioning grooves are provided with first adjusting holes that cooperate with the bolts.

[0006] Preferably, both ends of the adjusting block are in close contact with the sidewall of the positioning groove. Preferably, the adjusting block and the supporting inner sleeve are connected by a bearing.

[0007] Preferably, one end of the inner support sleeve is provided with a boss, and the other end of the inner support sleeve is provided with an external thread, on which a nut is fitted, and the bearing is located between the boss and the nut.

[0008] Preferably, the inner support sleeve and the bearing are interference-fitted.

[0009] Preferably, the inner support sleeve is detachable from the bearing.

[0010] Compared with the prior art, the beneficial effects of this utility model are: 1. This utility model transforms the direct sliding friction between the traditional follower post and the workpiece surface into a low-resistance relative rolling motion between the support inner sleeve and the workpiece by using a support inner sleeve that rotates synchronously with the workpiece. This fundamentally eliminates thread breakage, surface scratches, and grinding damage caused by excessive friction. It is particularly suitable for extremely fragile carbon-carbon composite screws, solving the industry problem of easy breakage and surface damage in the machining of slender carbon-carbon composite screws. It not only significantly improves product machining quality (reducing breakage, scratches, and fracture) and yield, but also enhances machining efficiency and equipment versatility, while ensuring machining stability.

[0011] 2. The base and support plate of this utility model are made of 45# steel and thickened to 25mm, forming a high-rigidity support frame. This frame can effectively absorb and disperse the radial force and vibration generated during the cutting process, providing reliable continuous support for slender rods. This greatly reduces the risk of breakage caused by workpiece vibration and bending, and ensures the stability of the processing.

[0012] 3. The longitudinal position of the support plate can be adjusted through the second adjustment hole on the ear plate; the vertical height of the adjustment block can be adjusted through the first adjustment hole on the positioning groove, realizing precise fine adjustment of the support hole position, ensuring that the axis of the support inner sleeve is strictly aligned with the center of the machine tool spindle, and precise alignment avoids additional stress caused by installation deviation of the workpiece.

[0013] 4. The support inner sleeve adopts a detachable design, allowing for the machining of slender screws of different diameters by simply replacing the support inner sleeve with one of different inner diameters. This modular, quick-change design enables "one machine for multiple uses," reducing tooling preparation time and improving machining efficiency.

[0014] 5. The inner support sleeve is made of Cr12 steel and has undergone high-temperature quenching treatment, resulting in high hardness, high wear resistance, and good hardenability. This allows it to withstand the abrasion of carbon-carbon composite materials for a long time, maintain the accuracy of the inner hole, significantly extend the service life of the core vulnerable parts of the tool holder, and reduce maintenance costs and downtime.

[0015] 6. Both ends of the support hole are rounded, which greatly reduces the frictional resistance between the support hole and the slender screw. The rounded corner design changes the sharp edges into smooth transition surfaces. The pressure is evenly distributed through the rounded corner surfaces, avoiding stress concentration and thus greatly reducing the risk of chipping the screw. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the present invention. Figure 2 ; Figure 3 This is a schematic diagram of the support plate structure; Figure 4 This is a cross-sectional view of the present invention; Figure 5 for Figure 4 A magnified structural diagram at point A; In the diagram: 1-base; 2-support plate; 201-first adjustment hole; 202-ear plate; 203-second adjustment hole; 204-displacement hole; 205-positioning groove; 3-adjustment block; 4-support inner sleeve; 401-bore; 402-external thread; 403-support hole; 404-rounded corner; 5-bearing; 6-nut. Detailed Implementation

[0017] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0018] like Figure 1 As shown, a follower holder for machining slender screws made of carbon-carbon composite materials includes a base 1, which is fixed on a movable seat of the cutter head. A support plate 2 is provided at the upper end of the base 1, and an adjusting block 3 passes through the support plate 2. A rotatable support inner sleeve 4 is provided inside the adjusting block 3, and a support hole 403 for supporting the slender screw is provided in the middle of the support inner sleeve 4. Figure 5As shown, both ends of the support hole 403 are equipped with fillets 404, which greatly reduces the frictional resistance between the support hole and the slender screw. The fillet design transforms sharp edges into smooth transition surfaces, and the pressure is evenly distributed through the fillet surfaces, avoiding stress concentration and thus greatly reducing the risk of chipping or breakage. The inner support sleeve 4 is made of Cr12 steel and has been high-temperature quenched, exhibiting good hardenability and wear resistance. The base 1 and support plate 2 are both made of 45# steel, with a thickness of 25mm, forming a high-rigidity support frame that effectively absorbs and disperses the radial force and vibration generated during the cutting process. This provides reliable continuous support for the slender rod, greatly reducing the risk of breakage caused by workpiece vibration and bending, and ensuring the stability of the machining process.

[0019] The specific structure is as follows: like Figure 2 As shown, the lower end of the support plate 2 is provided with ear plates 202 on both sides. The ear plates 202 are connected to the base 1 by bolts. The ear plates 202 are provided with long strip-shaped second adjustment holes 203 that cooperate with the bolts, which can conveniently adjust the position of the support plate 2. like Figure 3 As shown, the support plate 2 has a clearance hole 204 that mates with the adjusting block 3. Positioning grooves 205 are provided on both sides of the clearance hole 204. The two ends of the adjusting block 3 are connected to the positioning grooves 205 by bolts. The positioning grooves 205 have first adjusting holes 201 that mate with the bolts. The two ends of the adjusting block 3 are tightly against the sidewalls of the positioning grooves 205, allowing the adjusting block 3 to slide up and down along the positioning grooves 205 to adjust its position. The adjustment direction is perpendicular to the adjustment direction of the support plate 2. By adjusting the positions of the support plate 2 and the adjusting block 3, precise fine-tuning of the support hole 403 can be achieved, ensuring that the axis of the inner support sleeve 4 is strictly aligned with the center of the machine tool spindle. Precise alignment avoids additional stress on the workpiece caused by installation deviations. like Figure 4 As shown, in order to reduce friction, the adjusting block 3 and the supporting inner sleeve 4 are connected by a bearing 5. The supporting inner sleeve 4 and the bearing 5 are interference fit. One end of the supporting inner sleeve 4 is provided with a boss 401, and the other end of the supporting inner sleeve 4 is provided with an external thread 402. A nut 6 is fitted on the external thread 402. The bearing 5 is located between the boss 401 and the nut 6, which can prevent the supporting inner sleeve 4 from coming out of the bearing 5 and ensure the safety of use.

[0020] During use, the inner support sleeve 4 rotates with the slender screw, reducing the sliding resistance between the support hole 403 and the slender screw. Furthermore, the inner support sleeve 4 is detachable, enabling quick mold changes for processing long screws of different diameters, thus improving processing efficiency and quality.

[0021] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.

Claims

1. A trailing head for machining of carbon-carbon composite elongated screws, characterized in that: The device includes a base, with a support plate at the upper end of the base. An adjustment block runs through the support plate, and a rotatable support inner sleeve is provided inside the adjustment block. The support inner sleeve has a support hole in the middle for supporting a slender screw, and both ends of the support hole are rounded.

2. A trailing head for machining elongated carbon-carbon composite screws as set forth in claim 1, characterized in that: The lower end of the support plate is provided with ear plates on both sides. The ear plates are connected to the base by bolts. The ear plates are provided with elongated second adjustment holes that cooperate with the bolts.

3. A trailing head for machining elongated carbon-carbon composite rods as in claim 1, wherein: The support plate is provided with a clearance hole that cooperates with the adjusting block. Positioning grooves are provided on both sides of the clearance hole. The two ends of the adjusting block are connected to the positioning grooves by bolts. The positioning grooves are provided with a first adjusting hole that cooperates with the bolts.

4. A trailing head for machining elongated carbon-carbon composite screws as set forth in claim 3, characterized in that: The two ends of the adjusting block are tightly attached to the side wall of the positioning groove.

5. The follower tool holder for machining slender screws of carbon-carbon composite materials as described in claim 4, characterized in that: The adjusting block is connected to the supporting inner sleeve via a bearing.

6. A trailing head for machining elongated carbon-carbon composite screws as set forth in claim 4, characterized in that: One end of the inner support sleeve is provided with a boss, and the other end of the inner support sleeve is provided with an external thread, on which a nut is fitted. The bearing is located between the boss and the nut.

7. A trailing head for machining elongated carbon-carbon composite screws as in claim 6, wherein: The inner support sleeve and the bearing are interference-fitted.

8. A trailing head for machining elongated carbon-carbon composite screws as in claim 6, wherein: The inner support sleeve is detachable from the bearing.

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