Arc gear pump shell hole method

    Arc gear pump housing with two hole machining accuracy requirements of high. In the middle, small batch production, generally use the common machine tools and special tools to process, this process is very difficult to achieve theaccuracy requirements.

    Arc gear pump body processing the two hole process, a small hole 12.5 to 7,and the two holes the size limit of different; macroporous R18.41 close to the 8 level; a coaxial, verticality, position tolerance requirements, especially the smallgear position tolerance. Therefore, the difficulty of processing large hole.

    The second step hole processing is a key process, here only introduce the process of fixture design.

    (1) fixture plan and structure: the choice of the pump body G and two of 9diagonal hole for locating datum, fixture with two pin side positioning. Uses the straight linedividing form. Platen clamping part with two hook. Figure 2 is theschematic diagram of the fixture structure (only the key size and main part number mark the note:). Clamp 1 for angle shape, screws, cone pin arrangedon the carriage. Mobile index block 2 and clamp specific 1 through the dovetail guide cooperate, and bolt 3 lock. In the index block 2 is provided with acylindrical pin 4 and pin 9 cutting edge, through the two pin and plane P make parts positioning in dividing block 2, and two hook plate 14. The supporting seat for supporting the tool end 6. Hand pulling type cylindrical pin index on mechanism. For the convenience of operation, the workpiece is mounted on the right clamp, clamp, dividing block is provided with a hole, so that the tool in machining. To prevent chip into a 1 combined with the 2 surface, in the clipspecific 1 in the hole with anti chip set of 10.

    (2) fixture features: the use of referencesuperposition principle, the positioning error is small, the dividing precision. Tool supported at both ends, beating is small, high precision machining hole size. Clamping reliable, easy to operate.After long-term use of proof, can fully guarantee the machining accuracy, the deficiency in the course of processing inconvenient observation.

    (3) jig operation: the workpiece into the two positioning pin, tighten the hook clamp nut, longitudinal movement carriage. The cylindrical pin inserted into thepin hole 15 of the institutions in the processing the first hole. When processing the first hole, release the two locking nut 3, pull out the pin set mechanism 15,mobile index block 2, make on the cylindrical pin mechanism 15 inserted into the pin holes second holes, and screw down the nut 3, processing the second hole.

    (4) fixture installation requirements: manufacturing, cylindrical pin and bushingdividing on Mechanism of the preparation of 12, with the gap is not more than 0.01mm. When installed, to ensure the machining center fixture wire K and lathe spindle axis coaxial degree, the coaxial tolerance of 0.015mm. The positioning and supporting surface P and lathe spindle axis vertical, tolerance is 0.02mm. When the fixture installation adjustment, transverse feed to lock,longitudinal feed setting die block iron.