Positioning tool for machining outer contour of crank throw of large marine engine

Abstract

The utility model relates to a positioning tool for machining the outer contour of a crank throw of a large marine engine, which comprises a boring machine rotating workbench, and the upper surface of the boring machine rotating workbench is fixedly connected with a main table; a hot charging hole center positioning assembly corresponding to a crank hot charging hole is arranged on one side of the upper end face of the main table. Vertical screws are evenly distributed on the outer side of the hot charging hole center positioning assembly, and the bottoms of the screws are correspondingly connected with the main table in a threaded mode. The crank throw to be machined is arranged above the main table, and the hot charging hole of the crank throw to be machined is correspondingly arranged outside the hot charging hole center positioning assembly in a sleeving mode. The top of the screw rod is fixedly connected with a U-shaped pressing plate through a locking nut; the U-shaped pressing plate is tightly pressed on the upper end face of the crank throw hot charging hole under the action of the locking nut. When the outer contour of the crank throw is machined, only one-time clamping is needed, after an operator clamps a workpiece, machining of all working steps can be completed through one-time tool setting, the workload can be greatly reduced, the production efficiency can be improved, and the problems of errors and the like possibly caused by multiple times of tool setting can be effectively solved.

Description

Technical Field

[0001] This utility model relates to the field of marine engine crankshaft machining technology, and in particular to a positioning fixture for machining the outer contour of a large marine engine crankshaft. Background Technology

[0002] Currently, in the machining of crankshafts for large marine engines, the commonly used clamping method for machining the outer contour of the crankshaft lacks a positioning device between the center of the hot-fitting hole and the center of the rotary table. Figure 6 As shown, each clamping operation results in large errors, and the removal of the pressure plate is time-consuming and labor-intensive when machining the other side. Multiple clamping operations are required, necessitating repeated tool adjustments by the operator, leading to long working hours, a large workload, and low production efficiency. Furthermore, multiple tool adjustments increase the risk of operational errors, affecting machining quality. Therefore, a new clamping method is urgently needed to solve these problems. Summary of the Invention

[0003] To address the aforementioned problems, the purpose of this utility model is to provide a positioning fixture for machining the outer contour of a large marine engine crankshaft.

[0004] The technical solution adopted in this utility model is as follows:

[0005] This utility model proposes a positioning fixture for machining the outer contour of a large marine engine crankshaft, comprising a boring machine rotary table. The fixture is characterized by: a main table fixedly connected to the upper surface of the boring machine rotary table; a heat fitting hole center positioning component corresponding to the heat fitting hole of the crankshaft provided on one side of the upper surface of the main table; vertical screws evenly distributed on the outer side of the heat fitting hole center positioning component, the bottom of which is threadedly connected to the main table; the crankshaft to be machined is positioned above the main table, and its heat fitting hole is correspondingly fitted outside the heat fitting hole center positioning component; a U-shaped pressure plate is fixedly connected to the top of the screws by a locking nut; the U-shaped pressure plate is pressed tightly against the upper surface of the heat fitting hole of the crankshaft under the action of the locking nut.

[0006] Furthermore, the hot-fitting hole center positioning assembly includes a boss and adjusting bolts; the boss is fixedly connected to one side of the upper surface of the main platform; the adjusting bolts are evenly distributed around the boss in the circumferential direction, and the adjusting bolts are respectively radially threaded to the side wall of the boss.

[0007] Furthermore, the main table is fixedly connected to the rotary table of the boring machine by bolts and T-nuts.

[0008] Furthermore, several curved support points are set on the upper surface of the main platform.

[0009] Compared with the prior art, the present invention has the following beneficial effects:

[0010] When using this invention to process the outer contour of a crank, only one clamping is required. After clamping the workpiece, the operator can complete all processing steps in one tool setting, which can greatly reduce the operator's workload, improve production efficiency, and effectively avoid a series of problems such as errors that may occur due to multiple tool settings. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0012] Figure 2 for Figure 1 Schematic diagram of the connection structure between the center positioning component of the hot fitting hole and the main platform;

[0013] Figure 3 This is a schematic diagram of the main structure of the crank clamping mechanism of this utility model;

[0014] Figure 4 This is a side view of the crank clamping structure of this utility model;

[0015] Figure 5 This is a top view schematic diagram of the crank clamping structure of this utility model;

[0016] Figure 6 This is a schematic diagram of the clamping structure used in the machining of the original crankshaft.

[0017] In the attached drawings, the following labels are used: 1-boring machine rotary table; 2-main table; 3-T-nut; 4-crank fulcrum; 5-bolt; 6-crank; 7-adjusting bolt; 8-U-shaped pressure plate; 9-screw; 10-fastening nut; 11-bore. Detailed Implementation

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] It should be noted that in the description of this utility model, the terms "upper", "lower", "top", "bottom", "one side", "the other side", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not mean that the device or component must have a specific orientation, or be constructed and operated in a specific orientation.

[0020] See appendix Figures 1-4The present invention proposes a positioning fixture for machining the outer contour of a large marine engine crankshaft, including a boring machine rotary table 1. A main table 2 is fixedly connected to the upper surface of the boring machine rotary table 1. The bottom of the main table 2 is fixedly connected to the upper surface of the boring machine rotary table 1 by bolts 5 and T-nuts 3 around its perimeter.

[0021] A heat fitting hole center positioning component corresponding to the heat fitting hole of the crank 6 is provided on one side of the upper end face of the main platform 2; four vertical screws 9 are evenly distributed on the outer side of the heat fitting hole center positioning component, and the bottom of each screw 9 is threadedly connected to the main platform 2; the crank 6 to be processed is placed above the main platform 2, and its heat fitting hole is fitted onto the outside of the heat fitting hole center positioning component; a U-shaped pressure plate 8 is connected to the top of the screw; after the crank 6 is placed, the U-shaped pressure plate 8 is gradually pressed against the upper end face of the heat fitting hole of the crank 6 under the action of the locking nut 10 at the top of the screw 9.

[0022] Specifically, the hot-fitting hole center positioning assembly includes a boss 11 and adjusting bolts 7; the boss 11 is a cylindrical or prismatic structure, which is fixed to one side of the upper end face of the main platform 2; in this embodiment, four adjusting bolts 7 are provided, which are evenly distributed around the boss 11 in a circumferential direction, and the adjusting bolts 7 are respectively radially threaded to the side wall of the boss 11.

[0023] The upper surface of the main platform 2 is provided with several curved support points 4.

[0024] In use, the main table 2 and the rotary table 1 are first fixed together by T-nuts 3 and bolts 5. Once fixed, no further adjustment is needed. Even if other workpieces are replaced, no adjustment is required between them. Then, the adjusting bolts 7 are roughly adjusted according to the size of the hot fitting hole of the crank 6, so that the diameter of the circle formed by the outer ends of the four adjusting bolts 7 is slightly smaller than the diameter of the hot fitting hole of the crank 6. After placing the crank 6 flat on the main table 2, the adjusting bolts 7 are finely adjusted so that the center of the hot fitting hole of the crank 6 is completely aligned with the rotation axis of the rotary table 1 of the boring machine. At this time, the U-shaped pressure plate 8 is gradually pressed against the upper end face of the hot fitting hole of the crank 6 by locking the nut 10, thereby completing the clamping and fixing between the crank 6 and the main table 2.

[0025] Matters not covered in this utility model are common knowledge.

[0026] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Various modifications and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A positioning tool for machining the outer profile of a large marine engine crankshaft, comprising a boring machine rotary table, characterised in that: The upper surface of the rotary table of the boring machine is fixedly connected with a main table; one side of the upper end surface of the main table is provided with a hot-charging hole center positioning assembly corresponding to the hot-charging hole of the crank; vertical screw rods are uniformly distributed outside the hot-charging hole center positioning assembly; the bottom of the screw rod is in threaded connection with the main table; the crank to be machined is arranged above the main table, and the hot-charging hole thereof is correspondingly sleeved outside the hot-charging hole center positioning assembly; the top of the screw rod is fixedly connected with a U-shaped pressing plate through a locking nut; the U-shaped pressing plate is tightly pressed against the upper end surface of the hot-charging hole of the crank under the action of the locking nut.

2. The positioning tool for machining the outer profile of the crank web of a large marine engine according to claim 1, characterized in that: The hot-charging hole center positioning assembly comprises a boss and adjusting bolts; the boss is fixedly connected to one side of the upper end surface of the main table; the adjusting bolts are uniformly distributed around the boss, and are respectively in radial threaded connection with the side wall of the boss.

3. The positioning tool for machining the outer profile of the crank web of a large marine engine according to claim 1, characterized in that: The main table is fixedly connected with the rotary table of the boring machine through bolts and T-shaped nuts.

4. The positioning tool for machining the outer profile of the crank web of a large marine engine according to claim 1, characterized in that: The upper end surface of the main table is provided with a plurality of crank fulcrums.

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