Positioning tool for lettering annular workpiece

Abstract

The utility model relates to the technical fields of lettering frock, concretely is annular workpiece lettering positioning frock, including the power part of installation on the lettering equipment workstation and the clamping part fixed above power part, clamping part includes the upper shell fixed above power part, the locating shaft fixedly connected in the inside center of upper shell, the main bevel gear rotationally connected on locating shaft, the drive assembly for driving the rotation of main bevel gear and the clamping assembly for clamping workpiece, clamping assembly is equipped with three groups, and the circumference is evenly distributed, and each clamping assembly includes the auxiliary bevel gear meshing with main bevel gear, the screw rod fixedly connected in the center of auxiliary bevel gear and the chuck screw connection on screw rod, the both ends of screw rod are rotationally connected on locating shaft and the shell body of upper shell respectively, the drive assembly makes the chuck of three clamping assemblies simultaneously act through the rotation of drive main bevel gear. This frock can greatly improve the clamping positioning operation efficiency of workpiece lettering procedure, and the adaptability is high, and effectively guarantees workpiece quality.

Description

Technical Field

[0001] This utility model relates to the technical field of engraving fixtures, specifically to a positioning fixture for engraving on a ring-shaped workpiece. Background Technology

[0002] In the field of automotive parts manufacturing, ring-shaped workpieces such as gears, synchronizers, and gear hubs are widely used as core structural or functional components. To achieve functions such as product traceability, specification identification, brand labeling, and quality control, marking technologies such as laser engraving and pneumatic marking have become essential processes in the surface treatment of ring-shaped workpieces. Among these, the accuracy of the marking position directly affects the product's assembly compatibility and market acceptance.

[0003] During the engraving process, a fixture is needed to position the workpiece to be engraved. There are many types of existing fixtures for engraving ring-shaped workpieces, such as the existing technology "A Universal Laser Engraving Positioning Fixture Applicable to Ring-Shaped Objects" (Announcement No.: CN213318435U). This technology uses a limiting positioning block and two sliding positioning blocks evenly distributed circumferentially on the fixture's base plate. The limiting positioning block remains stationary, while the sliding positioning blocks are driven radially by a worm gear transmission and the action of an adjusting screw. This allows for adjustment of the clamping position according to the workpiece size. However, the existing technology still has the following technical problems: The existing technology uses two sliding positioning blocks. Each adjustment requires adjusting the position of each sliding positioning block individually, which is complex, time-consuming, and inefficient. In addition, the sliding positioning block includes a main positioning block and a positioning head. One end of the positioning head has an arc surface to achieve contact with the inner circle of the workpiece, but the end of the main positioning block away from the positioning head is a flat surface. This means that the fixture is only suitable for tensioning and clamping from the inner hole of the workpiece. For some workpieces with non-circular inner holes, such as internal gear rings, the positioning head is prone to pressing on the teeth of the internal gear ring when tensioning and positioning. Especially for internal gear rings with low material hardness, the existing fixture technology can easily cause tooth deformation or wear, reducing the quality of the workpiece. Utility Model Content This utility model provides a positioning fixture for engraving on a ring-shaped workpiece, which can solve the problems of complex and inefficient clamping and positioning operations of existing fixtures, as well as the problem of easily reducing the quality of workpieces when clamping workpieces with internal toothed ring structures.

[0004] This application provides the following technical solution: a ring-shaped workpiece engraving positioning fixture, including a power unit installed on the worktable of the engraving equipment and a clamping unit fixed above the power unit; The clamping part includes an upper shell fixed above the power unit, a positioning shaft fixedly connected to the center inside the upper shell, a main bevel gear rotatably connected to the positioning shaft, a drive assembly for driving the main bevel gear to rotate, and a clamping assembly for clamping the workpiece. The clamping assembly consists of three sets, evenly distributed around the circumference. Each set includes a secondary bevel gear meshing with the main bevel gear, a lead screw fixedly connected to the center of the secondary bevel gear, and a chuck threaded onto the lead screw. The two ends of the lead screw are rotatably connected to the positioning shaft and the upper shell, respectively. The top of the upper shell is provided with a sliding groove, and the upper end of the chuck extends above the sliding groove, allowing the chuck to slide along the groove. The upper end of the chuck is provided with a protrusion, and the side of the protrusion near the positioning shaft and the side away from the positioning shaft are both concentric arc surfaces. The drive assembly drives the rotation of the main bevel gear, causing the chucks of the three clamping assemblies to move simultaneously.

[0005] Beneficial effects: 1. Synchronous clamping and adjustment significantly improves positioning efficiency and solves the problems of complex and time-consuming operation. Existing technologies require individual sequential adjustment of the two sliding positioning blocks, which is cumbersome and inefficient. This fixture utilizes a linkage structure of a main bevel gear and three sets of auxiliary bevel gears, along with a drive assembly, to achieve synchronous movement of the clamping components. When the main bevel gear rotates, the three sets of auxiliary bevel gears meshing with it simultaneously drive their respective lead screws to rotate. Because the three clamping components are evenly distributed circumferentially, and the lead screws are threadedly connected to the chucks, the chucks are limited by the sliding grooves. This causes the rotation of the lead screws to cause the three chucks to synchronously move closer to or further away from the center along the sliding grooves. Therefore, the movement of the three chucks can be achieved simply by controlling the drive assembly, quickly clamping or releasing the workpiece. This simplifies the difficult positioning operation steps, significantly shortens the adjustment time, and is especially suitable for scenarios involving batch replacement of ring-shaped workpieces with different inner diameters, greatly improving positioning efficiency before engraving.

[0006] 2. Adapts to internal gear ring structure workpieces, avoiding tooth damage and ensuring workpiece quality. Existing technologies use a single arc surface for the clamping surface of the chuck, which easily compresses the teeth when clamping internal gear rings, leading to deformation or wear. This fixture features a chuck with a double-sided concentric arc surface. This structure allows for clamping of internal gear ring workpieces from the outer circumference of the gear ring via the chuck. Since the clamping surfaces of the chuck are both arc surfaces, they can form a close fit with the outer circumference of the workpiece, avoiding contact with the teeth of the internal gear ring. Furthermore, the evenly distributed clamping method of the three sets of chucks ensures balanced force on the outer circumference of the internal gear ring workpiece, reducing localized stress concentration. Even for internal gear rings with lower material hardness, stable and balanced force distribution effectively prevents clamping deformation and wear, solving the problem of reduced workpiece quality when clamping internal gear ring workpieces with existing fixtures, and ensuring the structural integrity and performance of the workpiece after engraving.

[0007] Furthermore, the drive assembly includes a drive bevel gear meshing with the main bevel gear and a rocker arm fixed at the center of the drive bevel gear. The rod portion of the rocker arm is rotatably connected to the housing of the upper shell, and one end of the rocker arm away from the drive bevel gear extends out of the upper shell.

[0008] Beneficial effects: The drive bevel gear meshes with the main bevel gear, and with the rocker arm's rocking action, the operator only needs to rotate the rocker arm extending outside the upper housing to drive the main bevel gear to rotate, thereby driving the three sets of chucks to move synchronously. Compared with the traditional individual adjustment method, no additional tools are needed, manual operation is more labor-saving, and the movement position of the chucks can be intuitively controlled, making operation more convenient, improving operational efficiency, and adapting to the rapid changeover needs in mass production.

[0009] Furthermore, the power unit is used to control the circumferential rotation of the upper shell; the power unit includes a motor fixed on the workbench of the engraving equipment, a lower shell located on one side of the motor, a worm gear fixedly connected to the main shaft of the motor, and a worm wheel meshing with the worm gear for transmission. The rods at both ends of the worm gear are rotatably connected to the shell of the lower shell, and a rotating shaft is fixed at the center of the worm wheel. The lower end of the rotating shaft is rotatably connected to the bottom of the lower shell.

[0010] Beneficial effects: The motor drives the rotating shaft to rotate smoothly at low speed via worm gear transmission. The motor can precisely control the angle and speed of the rotating shaft, allowing the workpiece to rotate at a certain angle as needed. This adapts to the requirements of full-circumference or segmented engraving on the workpiece, especially for pneumatic marking machines. By rotating the workpiece, the overall engraving accuracy and efficiency of the pneumatic marking machine are guaranteed. Furthermore, the lower housing is symmetrically provided with bearing seats, and deep groove ball bearings are installed in the bearing seats. The shank portions at both ends of the worm gear are fixed in the inner rings of the deep groove ball bearings.

[0011] Beneficial effects: The symmetrical bearing seats and deep groove ball bearings installed in the lower shell provide stable support for the worm, reduce frictional resistance during worm rotation, ensure smooth transmission, and prevent worm wobbling from affecting the meshing accuracy of the worm wheel; it also limits the axial and radial movement of the worm, ensuring that the worm and worm wheel are always precisely meshed, improving the stability of power transmission, and ensuring the angular accuracy when the workpiece is rotated for engraving.

[0012] Furthermore, a mounting block is fixed to the bottom of the lower shell, and the lower end of the rotating shaft is rotatably connected to the mounting block via a bearing.

[0013] Beneficial effects: The mounting block at the bottom of the lower shell, in conjunction with the bearing connecting the lower end of the shaft, provides stable axial support for the shaft, reduces friction during shaft rotation, ensures smooth rotation, and prevents workpiece positioning from being affected by shaft wobbling; it also limits radial movement of the shaft, ensuring greater stability of the workpiece as it rotates with the shaft, and improving angular accuracy and stability during the engraving process.

[0014] Furthermore, an intermediate component is fixed to the upper end of the rotating shaft, and a circular hole is opened at the top of the lower shell. The intermediate component extends above the circular hole, and the inner diameter of the circular hole is larger than the outer diameter of the intermediate component. The upper end of the intermediate component is fixedly connected to the upper shell by screws.

[0015] Beneficial effects: The upper end of the shaft is connected to the upper shell through the intermediate part, and the inner diameter of the round hole at the top of the lower shell is larger than the outer diameter of the intermediate part. This not only achieves a stable connection between the power unit and the clamping unit, ensuring that the power of the shaft can be accurately transmitted to the upper shell to drive the workpiece to rotate, but also provides space for the installation and rotation of the intermediate part, avoiding friction between the intermediate part and the inner wall of the round hole of the lower shell, ensuring smooth transmission. At the same time, the screw connection facilitates the disassembly and assembly of the upper shell and the intermediate part, improving the efficiency of tooling maintenance and replacement. Attached Figure Description

[0016] Figure 1 This is a front view of the structure of this utility model.

[0017] Figure 2 for Figure 1 Top view of the power unit and clamping unit.

[0018] Figure 3 for Figure 2 The top view after removing the clamping part.

[0019] Figure 4 for Figure 2 Sectional view of AA. Detailed Implementation

[0020] The following detailed description illustrates the specific implementation method: The markings in the accompanying drawings include: motor 1, coupling 2, worm gear 3, upper shell 4, protrusion 5, engraving machine 6, lower shell 7, worktable 8, deep groove ball bearing 9, worm wheel 10, positioning shaft 11, chuck 12, slide 121, rocker arm 13, drive bevel gear 131, rotating shaft 14, mounting block 15, secondary bevel gear 16, lead screw 161, main bevel gear 17, and intermediate part 18.

[0021] Example 1 like Figures 1 to 4 As shown, the ring-shaped workpiece engraving positioning fixture includes a power unit installed on the worktable 8 of the engraving machine 6 and a clamping unit fixed above the power unit. like Figure 2 and Figure 3 As shown, the power unit includes a motor 1 fixed to the worktable 8 with screws, a lower housing 7 located on one side of the motor 1, a worm gear 3 fixedly connected to the main shaft of the motor 1 via a coupling 2, and a worm wheel 10 meshing with the worm gear 3 for transmission. The motor 1 is a servo motor 1, electrically connected to the control system of the engraving machine 6. Symmetrical bearing seats are provided inside the lower housing 7, and deep groove ball bearings 9 are installed inside the bearing seats. The rods at both ends of the worm gear 3 are fixed inside the inner rings of the deep groove ball bearings 9. Figure 4As shown, a rotating shaft 14 is fixed at the center of the worm gear 10, and a mounting block 15 is fixed at the bottom of the lower shell 7. The lower end of the rotating shaft 14 is rotatably connected to the mounting block 15 via a bearing, which is omitted in the figure. An intermediate piece 18 is fixed at the upper end of the rotating shaft 14. A circular hole is opened at the top of the lower shell 7, and the intermediate piece 18 extends above the circular hole. The inner diameter of the circular hole is larger than the outer diameter of the intermediate piece 18.

[0022] like Figure 2 and Figure 4 As shown, the clamping part includes an upper shell 4 fixed to the upper end of the intermediate part 18 by screws, a positioning shaft 11 fixedly connected to the center inside the upper shell 4, a main bevel gear 17 rotatably connected to the positioning shaft 11 by bearings (the bearings are omitted in the figure), a drive assembly for driving the main bevel gear 17 to rotate, and a clamping assembly for clamping the workpiece.

[0023] like Figure 4 As shown, the drive assembly includes a drive bevel gear 131 that meshes with the main bevel gear 17 and a rocker arm 13 fixed at the center of the drive bevel gear 131. The rod of the rocker arm 13 is rotatably connected to the housing of the upper shell 4 by means of a bearing (the bearing is omitted in the figure). The end of the rocker arm 13 away from the drive bevel gear 131 extends to the outside of the side wall of the upper shell 4.

[0024] The clamping components are arranged in three sets, evenly distributed around the circumference, for easy structural demonstration. Figure 4 Only one set of clamping components is shown. Each set of clamping components includes a secondary bevel gear 16 meshing with the main bevel gear 17, a lead screw 161 fixedly connected to the center of the secondary bevel gear 16, and a chuck 12 threadedly connected to the lead screw 161. The two ends of the lead screw 161 are rotatably connected to the positioning shaft 11 and the housing of the upper shell 4, respectively. The top of the upper shell 4 is provided with a slide groove 121, and the upper end of the chuck 12 extends above the slide groove 121, and the chuck 12 can slide along the slide groove 121. The upper end of the chuck 12 is provided with a protrusion 5. Figure 4 The left and right sides of the central protrusion 5 are one side close to the positioning shaft 11 and the other side away from the positioning shaft 11. Both sides are concentric arc surfaces with the center of the positioning shaft 11 as the center.

[0025] The method of using this clamping fixture is as follows: First, the workpiece is clamped: Rotating the rocker arm 13 causes the drive bevel gear 131 to rotate, which in turn causes the main bevel gear 17 to rotate. The main bevel gear 17 drives three sets of evenly distributed circumferential secondary bevel gears 16 to rotate synchronously. The secondary bevel gears 16 drive the lead screw 161 to rotate. Since the lead screw 161 is threadedly connected to the chuck 12 and the chuck 12 is limited by the slide groove 121, the three sets of chucks 12 can move synchronously along the slide groove 121 in a direction away from or towards the center of the positioning shaft 11. The appropriate movement can be selected based on the structure of the workpiece being clamped. Figure 4The left and right sides of the protrusion 5 on the chuck 12 serve as contact surfaces. If clamping is required from the inner hole of the workpiece, the left side of the protrusion 5 is selected as the clamping surface. If clamping is required from the outer surface of the workpiece, the right side of the protrusion 5 is rotated to serve as the clamping surface. Rotate the rocker arm 13 until the spacing of the chuck 12 is suitable for placing the workpiece. Place the annular workpiece between the three sets of protrusions 5, and continue to rotate the rocker arm 13 so that the three sets of chucks 12 clamp the outer circle of the workpiece or tighten the inner hole of the workpiece until the workpiece is stably clamped.

[0026] Then adjust the engraving angle: According to the engraving requirements, start motor 1 of the power unit. Motor 1 drives worm 3 to rotate through coupling 2. Worm 3 meshes with worm wheel 10 for transmission. Worm wheel 10 drives shaft 14 to rotate. Shaft 14 drives upper shell 4 and the clamped workpiece to rotate synchronously through intermediate part 18. By controlling the start, stop and speed of motor 1, adjust the workpiece to the appropriate engraving starting position.

[0027] Next, the engraving operation is performed: once the workpiece is positioned correctly, the engraving machine 6 is started to begin engraving. After engraving is complete, the motor 1 is turned off, the rocker arm 13 is rotated to release the chuck 12, and the workpiece is removed. If maintenance is required, the upper shell 4 and the intermediate part 18 can be disassembled with screws to inspect and replace the internal components; if continued use is desired, the tooling should be kept clean.

[0028] The above are merely embodiments of this utility model, and the utility model is not limited to the field covered by this embodiment. Commonly known structures and characteristics in the solutions are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of this utility model, and these should also be considered within the scope of protection of this utility model. These modifications will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A positioning fixture for engraving characters on a ring-shaped workpiece, characterized in that: It includes a power unit mounted on the worktable of the engraving equipment and a clamping unit fixed above the power unit; The clamping part includes an upper shell fixed above the power unit, a positioning shaft fixedly connected to the center inside the upper shell, a main bevel gear rotatably connected to the positioning shaft, a drive assembly for driving the main bevel gear to rotate, and a clamping assembly for clamping the workpiece. The clamping assembly consists of three sets, evenly distributed around the circumference. Each set includes a secondary bevel gear meshing with the main bevel gear, a lead screw fixedly connected to the center of the secondary bevel gear, and a chuck threaded onto the lead screw. The two ends of the lead screw are rotatably connected to the positioning shaft and the upper shell, respectively. The top of the upper shell is provided with a sliding groove, and the upper end of the chuck extends above the sliding groove and can slide along the sliding groove. The upper end of the chuck is provided with a protrusion, and the side of the protrusion near the positioning shaft and the side away from the positioning shaft are both concentric arc surfaces. The drive assembly drives the rotation of the main bevel gear, causing the chucks of the three clamping assemblies to move simultaneously.

2. The annular workpiece engraving positioning fixture according to claim 1, characterized in that: The drive assembly includes a drive bevel gear meshing with the main bevel gear and a rocker arm fixed at the center of the drive bevel gear. The rod portion of the rocker arm is rotatably connected to the housing of the upper shell, and the end of the rocker arm away from the drive bevel gear extends out of the upper shell.

3. The annular workpiece engraving positioning fixture according to claim 2, characterized in that: The power unit is used to control the circumferential rotation of the upper shell; the power unit includes a motor fixed on the worktable of the engraving equipment, a lower shell located on one side of the motor, a worm gear fixedly connected to the main shaft of the motor, and a worm wheel meshing with the worm gear for transmission. The rods at both ends of the worm gear are rotatably connected to the shell of the lower shell, and a rotating shaft is fixed at the center of the worm wheel. The lower end of the rotating shaft is rotatably connected to the bottom of the lower shell.

4. The annular workpiece engraving positioning fixture according to claim 3, characterized in that: The lower housing is symmetrically provided with bearing seats, and deep groove ball bearings are installed in the bearing seats. The shank portions at both ends of the worm gear are fixed in the inner rings of the deep groove ball bearings.

5. The annular workpiece engraving positioning fixture according to claim 4, characterized in that: A mounting block is fixed to the bottom of the lower shell, and the lower end of the rotating shaft is rotatably connected to the mounting block through a bearing.

6. The annular workpiece engraving positioning fixture according to claim 5, characterized in that: An intermediate component is fixed to the upper end of the rotating shaft. A circular hole is opened at the top of the lower shell. The intermediate component extends above the circular hole. The inner diameter of the circular hole is larger than the outer diameter of the intermediate component. The upper end of the intermediate component is fixedly connected to the upper shell by screws.

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