Rotatable turning tool for machining small-aperture large cavity of aero-engine disc part

Abstract

The invention discloses a rotatable turning tool for machining a small-aperture large cavity of an aero-engine disc part, which comprises a tool bar, a tool bit and a blade, the tool bit is rotatably connected with the tool bar through a slotted hexagonal screw and a hexagonal nut, the center of the tool bit is superposed in an initial state, and the angle of the tool bit can be adjusted after the tool bit is rotated; the blade is connected with the tool bit through the inner hexagon screw, when the tool bit rotates around the tool bar, the blade can synchronously rotate to the position to be machined along with the tool bit, it is guaranteed that the blade cannot move in the rotating process through connection rigidity, and it is guaranteed that the machining position is accurate. The locking screw is connected with the cutter bar and the cutter head in a penetrating mode, the locking screw can drive the cutter head to rotate around the connecting point when rotating, and meanwhile locking is achieved through cooperation with the hexagon nut. According to the invention, 180-degree directional adjustment can be realized so as to meet the processing requirement of a cavity which is 2-3 times larger than the diameter of an inner hole.

Description

Technical Field

[0001] This invention relates to a rotatable turning tool for machining small-diameter large cavities in disc-shaped parts of aero-engines, belonging to the field of precision machining technology for aero-engine components. Background Technology

[0002] The machining of disc-shaped parts for aero-engines often presents the challenge of machining large cavities with small diameters. Disc structures have narrow spaces, extremely high precision requirements, and are often made of difficult-to-machine materials such as high-temperature alloys and titanium alloys. Conventional turning tools often suffer from poor tool reachability and low machining efficiency when machining internal cavities. Due to the limitations of small-diameter channels, such as... Figure 1 As shown, it is often difficult to complete the machining of cavities with a depth of 2-3 times the diameter, so there is an urgent need for a new type of rotatable turning tool. Summary of the Invention

[0003] In view of the above-mentioned prior art, the present invention provides a rotatable turning tool for machining large cavities with small diameters in disc-shaped parts of aero-engines. By achieving 180° rotation angle orientation adjustment, it can meet the requirements for machining cavities with diameters greater than 2-3 times the inner diameter.

[0004] This invention is achieved through the following technical solution: A rotatable turning tool for machining small-diameter large cavities in disc-shaped parts of aero-engines includes a tool holder, a tool head, and an insert. The tool head is rotatably connected to the tool holder via slotted hexagonal screws and hexagonal nuts, with the centers coinciding initially and the angle adjustable after rotation. The insert is connected to the tool head via internal hexagonal screws. When the tool head rotates around the tool holder, the insert rotates synchronously with the tool head to the machining position. The rigidity of the connection ensures that the insert will not shift during rotation, guaranteeing precise machining position.

[0005] A locking screw is used to connect the tool holder and the tool head. When the locking screw rotates, it can drive the tool head to rotate around the connection point, and at the same time, it can lock in place with a hexagonal nut. The tool holder has an internal threaded hole that matches the locking screw. The locking screw completely passes through the internal threaded hole and is tightly engaged by the thread. The tool head has a non-circular mounting groove that matches the head of the locking screw. The head of the locking screw is machined into a shape that corresponds to the non-circular mounting groove. After the head of the locking screw is inserted into the non-circular mounting groove, it fits completely without gaps.

[0006] Preferably, on the contact surface between the cutter bar and the cutter head, the cutter bar is provided with two pressure spring slots, and a pressure spring is installed in the pressure spring slots; the cutter head is provided with a spherical positioning groove, which is correspondingly arranged with the pressure spring slots, and a positioning steel ball is placed in the spherical positioning groove; the pressure spring always applies a pushing force to the positioning steel ball, so that the positioning steel ball fits tightly against the spherical positioning groove of the cutter head; the two spherical positioning grooves are smoothly connected by a semi-circular arc guide groove, and the positioning steel ball can move along the guide groove under the compression of the pressure spring.

[0007] Preferably, a sawtooth positioning mechanism is also provided on the contact surface between the tool holder and the tool head. Specifically, on the side of the tool holder, a V-shaped sawtooth positioning groove A is machined around the mounting hole of the slotted hexagonal screw. The distribution range of the V-shaped sawtooth positioning groove A covers the corresponding area after the tool head is rotated 180°. On the side of the tool head, a V-shaped sawtooth positioning groove B that perfectly matches the V-shaped sawtooth positioning groove A is machined.

[0008] Preferably, a clamping screw is provided on the contact surface between the tool holder and the tool head. The clamping screw is used to further compress the contact surface between the tool holder and the tool head. In addition, the clamping screw, in conjunction with the meshing action of the V-shaped sawtooth positioning groove, can greatly improve the vibration resistance of the tool head during the machining process and avoid slight displacement of the tool head due to cutting force.

[0009] Preferably, the width and depth of the guide groove match the diameter of the positioning steel ball, allowing the steel ball to slide along the groove but preventing lateral deviation, thus structurally limiting the rotation trajectory and preventing "deviation". The guide groove adopts a semi-circular arc trajectory with an arc strictly corresponding to 180°, ensuring that the positioning steel ball can accurately complete half a circle along the groove when the cutter head rotates, without any angular deviation. The end of the guide groove smoothly connects with the spherical positioning grooves on both sides of the cutter head, without any steps or jamming structures, ensuring that the steel ball can smoothly slide into the groove under the spring force to complete the positioning action.

[0010] Preferably, the tool holder has a coolant channel inside, and the coolant channel outlet on the tool head is close to the blade mounting position, so the coolant can be directly sprayed onto the cutting edge of the blade. The tight connection between the blade and the tool head does not affect the flow direction of the coolant, which can effectively reduce the cutting temperature and extend the blade life.

[0011] The beneficial effects of this invention are as follows: 1. This lathe tool uses a rotatable cutting head, which allows it to pass through the part inlet with a smaller cross section and enter the cavity. After entering the cavity, the cutting head can be rotated to the surface to be machined, thereby achieving high-precision, high-efficiency, and high-quality machining of large cavities. 2. Precise and reliable positioning: It provides accurate 180° positioning through positioning steel balls and pressure springs, and the correct rotation position can be judged by feel. 3. It has a simple structure, compact mechanism design, good rigidity, low manufacturing cost, and the blade can be replaced after wear. Attached Figure Description

[0012] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0013] Figure 1 This is a simplified structural diagram of the part (thick lines indicate the surfaces to be machined). Figure 2 This indicates the tool locking state. Figure 1 ; Figure 3 This indicates the tool locking state. Figure 2 ; Figure 4 This is a schematic diagram of the cutting tool entering the cavity; Figure 5 This is a diagram showing the cutting head rotating 180° to enter the cavity for machining. Figure 6 Cutter head structure diagram Figure 1 ; Figure 7 Cutter head structure diagram Figure 2 ; Figure 8 Schematic diagram of tool holder structure Figure 1 ; Figure 9 Schematic diagram of tool holder structure Figure 2 ; In the diagram: 1-tool holder, 2-tool head, 3-clamping screw, 4-blade, 5-hexagonal nut, 6-locking screw, 7-positioning steel ball, 8-pressure spring, 9-pressure spring slot, 10-spherical positioning groove, 11-guide groove, 12-serrated positioning groove A, 13-serrated positioning groove B, 14-coolant channel. Detailed Implementation

[0014] The embodiments of this application will now be described in detail with reference to the accompanying drawings.

[0015] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other.

[0016] The present invention will be further described below with reference to embodiments.

[0017] A rotatable turning tool for machining large cavities with small diameter holes in disc-shaped parts of aero-engines, such as... Figures 2 to 8As shown, the tool includes a tool holder 1, a tool head 2, and a blade 4. The tool head 2 is rotatably connected to the tool holder 1 by a slotted hexagonal screw and a hexagonal nut 5. Initially, the centers coincide, and the angle can be adjusted after rotation. The blade 4 is connected to the tool head 2 by an internal hexagonal screw. The tool holder 1 has a coolant channel 14 inside, and the coolant channel outlet on the tool head 2 is close to the blade mounting position. A locking screw 6 is used to connect the tool holder 1 and the tool head 2. The tool holder 1 has an internal threaded hole that matches the locking screw 6. The locking screw 6 completely passes through the internal threaded hole and is tightly engaged by the thread. The tool head 2 has a non-circular mounting groove that matches the head of the locking screw 6. The head of the locking screw 6 is machined into a shape that corresponds to the non-circular mounting groove. After the head of the locking screw 6 is inserted into the non-circular mounting groove, it fits completely.

[0018] Furthermore, on the contact surface between the cutter bar 1 and the cutter head 2, the cutter bar 1 is provided with two pressure spring slots 9, and a pressure spring 8 is installed in the pressure spring slots 9; the cutter head 2 is provided with a spherical positioning groove 10, which is correspondingly arranged with the pressure spring slots 9, and a positioning steel ball 7 is placed in the spherical positioning groove 10; the pressure spring 8 always applies a pushing force to the positioning steel ball 7, so that the positioning steel ball 7 fits tightly against the spherical positioning groove 10 of the cutter head 2; the two spherical positioning grooves 10 are smoothly connected by a semi-circular arc guide groove 11, and the positioning steel ball 7 can move along the guide groove 11 under the pressure of the pressure spring 8.

[0019] Furthermore, a sawtooth positioning mechanism is provided on the contact surface between the tool holder 1 and the tool head 2. Specifically, on the side of the tool holder 1, a V-shaped sawtooth positioning groove A12 is machined around the mounting hole of the slotted hexagonal screw. The distribution range of the V-shaped sawtooth positioning groove A12 covers the corresponding area after the tool head rotates 180°. On the side of the tool head 2, a V-shaped sawtooth positioning groove B13 is machined that perfectly matches the V-shaped sawtooth positioning groove A12.

[0020] Furthermore, a clamping screw 3 is provided on the contact surface between the cutter bar 1 and the cutter head 2. The clamping screw 3 is used to further compress the contact surface between the cutter bar 1 and the cutter head 2.

[0021] Furthermore, the width and depth of the guide groove 11 are matched with the diameter of the positioning steel ball 7, allowing the steel ball to slide along the groove but preventing lateral displacement.

[0022] Implementation process of this embodiment: Step 1: Unlock (Remove positioning and locking) Use a socket wrench to loosen the hex nut 5. The loosening degree should be greater than the serrated positioning depth of the cutter bar 1 and the cutter head 2 to release the locking state of the V-shaped serrated positioning groove. At this time, the positioning steel ball 7 still fits the cutter head positioning groove under the action of the pressure spring 8, but is no longer restricted by the nut pressure and can move along the guide groove 11. Step 2: Rotate (adjust 180° angle) Turn the locking screw 6 with a flathead wrench to drive the cutter head 2 to rotate around the connection point of the cutter head 1; during the rotation of the cutter head, the positioning steel ball 7 slides along the 180° guide groove 11 preset by the cutter head to ensure accurate rotation trajectory and avoid deviation; Step 3: Positioning (Precise angle fixation) When the cutter head 2 rotates to 180°, the positioning steel ball 7 is pushed into the symmetrical spherical positioning grooves 10 on both sides of the cutter head 2 by the pressure spring 8. The operator can judge whether the positioning is in place by touch. When the positioning steel ball 7 is inserted into the spherical positioning groove 10, there will be a clear "sticking" feeling, which realizes the precise fixation of the 180° angle. Step 4: Lock (Restore rigidity) Tighten the hex nut 5 again with a socket wrench to re-engage the V-shaped serrated positioning groove of the cutter shank 1 and the cutter head 2, restoring the rigid connection; at this time, the position of the cutter head 2 is completely fixed, and small-diameter large cavity cutting can be performed.

[0023] The above description is merely a specific embodiment of the present invention and should not be construed as limiting the scope of the invention. Therefore, any substitution of equivalent components or equivalent changes and modifications made within the scope of protection of this patent should still fall within the scope of this patent. Furthermore, the technical features, technical features and technical solutions, and technical solutions in this invention can be freely combined and used.

Claims

1. A rotatable turning tool for machining large cavities with small diameters in disc-shaped parts of aero-engines, characterized in that: It includes a tool holder (1), a tool head (2) and a blade (4). The tool head (2) is rotatably connected to the tool holder (1) by a slotted hexagonal screw and a hexagonal nut (5). The center coincides in the initial state and the angle can be adjusted after rotation. The blade (4) is connected to the tool head (2) by an internal hexagonal screw. A locking screw (6) is used to connect the tool holder (1) and the tool head (2). The tool holder (1) has an internal thread hole that matches the locking screw (6). The locking screw (6) completely passes through the internal thread hole and is tightly engaged by the thread. The tool head (2) has a non-circular mounting groove that matches the head of the locking screw (6). The head of the locking screw (6) is machined into a shape that corresponds to the non-circular mounting groove. After the head of the locking screw (6) is inserted into the non-circular mounting groove, it fits completely.

2. The rotatable turning tool for machining small-diameter large cavities in disc-shaped parts of aero-engines as described in claim 1, characterized in that: On the contact surface between the cutter bar (1) and the cutter head (2), the cutter bar (1) is provided with two pressure spring slots (9), and a pressure spring (8) is installed in the pressure spring slots (9); the cutter head (2) is provided with a spherical positioning groove (10), which is correspondingly set with the pressure spring slots (9), and a positioning steel ball (7) is placed in the spherical positioning groove (10); the pressure spring (8) always applies a pushing force to the positioning steel ball (7), so that the positioning steel ball (7) fits tightly against the spherical positioning groove (10) of the cutter head (2); the two spherical positioning grooves (10) are smoothly connected by a semi-circular guide groove (11), and the positioning steel ball (7) can move along the guide groove (11) under the pressure of the pressure spring (8).

3. The rotatable turning tool for machining small-diameter large cavities in disc-shaped parts of aero-engines as described in claim 2, characterized in that: A sawtooth positioning mechanism is also provided on the connecting and contacting surface between the tool holder (1) and the tool head (2). Specifically, on the side of the tool holder (1), a V-shaped sawtooth positioning groove A (12) is machined around the mounting hole of the slotted hexagonal screw. The distribution range of the V-shaped sawtooth positioning groove A (12) covers the corresponding area after the tool head rotates 180°. On the side of the tool head (2), a V-shaped sawtooth positioning groove B (13) that is completely matched with the V-shaped sawtooth positioning groove A (12) is machined.

4. The rotatable turning tool for machining small-diameter large cavities in disc-shaped parts of aero-engines as described in claim 1, characterized in that: A clamping screw (3) is also provided on the contact surface between the tool holder (1) and the tool head (2). The clamping screw (3) is used to further compress the contact surface between the tool holder (1) and the tool head (2).

5. A rotatable turning tool for machining small-diameter large cavities in disc-shaped parts of aero-engines as described in claim 1, characterized in that: The width and depth of the guide groove (11) match the diameter of the positioning steel ball (7), allowing the steel ball to slide along the groove but preventing lateral displacement.

6. The rotatable turning tool for machining small-diameter large cavities in disc-shaped parts of aero-engines as described in claim 1, characterized in that: The tool holder (1) has a coolant channel (14) inside, and the coolant channel outlet on the tool head (2) is close to the blade mounting position.

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