To prevent the deformation of beam gantry milling screw device

To prevent the deformation of beam gantry milling screw device - 2019 01 - 04 tara ( Qiqihar second machine ( Group) Co. , LTD. ) Ball screw is the most commonly used on machine tools and precision mechanical transmission device, its main function is to convert rotary motion to linear motion, or convert torque into axial force repeatedly, at the same time with high-precision reversibility and the characteristics of high efficiency. So a lot of modern numerical control machine tool feed direction using the ball screw. Feed milling planer beams, the author of this paper the optimization of the deformation problem of ball screw were improved. Structure to introduce large gantry milling machine beam structure as shown in figure 1, through on the beams with servo motor provides rotation torque, the ends of the ball screw fixed in a screw seat with bearing combination, can rotate freely, screw wire mother fixed on the slip board box, by rotating linear shift along the slip board box beam line Y to reciprocating movement, the structure will be high precision, quick response performance of ball screw all play out. Problems existing in CNC gantry milling and boring machine for large heavy cutting plane or space surface machining and surface contour, prone to bending deformation. Normally cold rolled screw deformation under the condition of screw diameter of 100 mm, and grinding screw in the case of a diameter of 60 mm bending deformation, and because of the large gantry milling and boring machine Y to span stroke compared commonly big, generally in more than 3 m, even to processing and wind power, water conservancy and nuclear power some economic benefit is obvious, such as large-scale mechanical parts, require span has reached around 6 m milling planer, so the screw length is longer. Screw under the condition of the weight of more prone to deformation, thus seriously affect the use of ball screw precision and life, has affected the production cycle and economic benefits. Therefore solve the deformation to improve the machining precision of the leadscrew, reduce the production cost and increase economic benefits have a vital role. Solution as shown in figure 2, the beam is commonly box-type structure, in the middle of the body near the length of the screw hole position, inside the whole support device is embedded in the beam, through the screw on the casing wall, complete fixed. Highlight on the surface of the beam before the entire unit shaft end at the bottom of the ball screw. When the slip board box along the beam Y to mobile arrived near the support device, slip board box cant by bearing contact, so crowded supporting shaft axis along a straight line bearing beam embedded enclosure. Through the fixed linear bearing, ensure the linear motion precision of the shaft and the supporting position precision. When slip board box away from support position, supporting shaft under the action of compression spring back to the starting position, so as to ensure the ball screw is in the support state, the lock nut to control the length of the spring compression, to ensure that the copper effectively contact with screw. Copper through the screw in the steps of the support shaft, copper because the texture is soft, no damage to the screw and easily replaced. The above process is in the slip board box near the support device running. When the slip board box away from supporting device, the device is always lifts the ball screw, achieve the goal of support reduced gravity deformation. Conclusion with the rapid development of science and technology, with the country of aerospace, shipbuilding, wind power, hydropower, war industry, mining, trains, cars and plenty of input, heavy machinery and other mechanical processing of CNC gantry boring and milling machine parameters and composite degree is becoming more and more demanding schedule, large car milling compound machining center arises at the historic moment, the beam span over 6 m structure requirement, the structure can effectively solve the machining error of deformation that is caused by screw. Now the device has been applied to the customer's products, won the user's high praise. Source: the metal processing ( Cold working) Magazine,