What Is a Power Planer?

Gantry planing machine (planing machine) is mainly used for planing large workpieces. It can also process multiple parts on the workbench at the same time. It is the industrial master machine. The working table of the gantry planer takes the workpiece through the portal frame for linear reciprocating motion, and the idle travel speed is greater than the working travel speed. The beam is generally equipped with two vertical tool holders, and the tool holder slide can be rotated by an angle in the vertical plane, and can be moved laterally along the beam;

Gantry planer with gantry frame and horizontal long bed

Introduction to Planer

Non-cylindrical surfaces with a small length can be processed by CNC milling machines or wire cutting (single piece production). But when the non-cylindrical surface reaches a certain length, using the above two methods is helpless or the processing cost is too high. Such as the rotors of series Roots vacuum pumps and Roots blowers (shown in Figure 1, the cross-sectional contour line is composed of multiple involutes, epicycloids and arcs, and the length is more than 300mm), the blades of the large-scale water ring pump impeller model ( The section outline is composed of multiple straight lines and arcs, and the length is more than 500mm). In order to adapt to the machining of cylindrical workpieces whose cross-section contours are complex curves, the author has developed a CNC system for planers based on IPC, and numerically modified a small gantry planer of a vacuum pump manufacturer. ^[1]

Cut

1 Mechanical transformation of small planer

figure 2

Figure 2 is a schematic diagram of a CNC planer converted from a small planer.

The method of NC transformation of small planer planer is to change the manual adjustment tool post into a NC tool post driven by a stepper motor. The Z stepper motor controls the vertical movement of the tool post, and the X stepper motor controls the horizontal movement of the tool post. . Install three proximity switches on the part of the slide base near the slider, and fix a slider position block (iron block) on the slider that is parallel to the three proximity switches and can be accessed by the three switches during the movement. Both are used to detect the movement direction and position of the slider. In addition, a simple tool setting device is installed on the slide table. After calculation of the load (friction, inertia, etc.), the stepping motors that drive the tool post up and down (Z coordinate axis) and left and right (X coordinate axis) are selected as 110BF003 and 130BF003, respectively. The pulse equivalent of these two coordinate movements is 0.01mm. ^[1]

Gantry planer system hardware

This CNC system uses a PC bus and a 486CPU industrial control machine with a main frequency of 100MHZ as the host. It has a standard 16-bit data bus and a flexible plug-in structure with extended functions. The structure can be optimized according to the system requirements (Figure 3). Figure 3 CNC system hardware structure of planer The numerical control system uses 8255A on the IO / TIMER (parallel input / output / timer) interface board to control the movement of two stepper motors, receives the slide return and position sensor signals, and the tool holder limit Switch signal, function selection switch signal. The 8253 timer on the interface board is used to interrupt the running service program of the stepper motor. The clock frequency is 2MHz. ^[1]

image 3

Gantry planer

The author used a planer CNC system developed by himself to numerically transform a small gantry planer of an enterprise, and successfully realized the processing of a series of water ring pump impeller blade models and the mass production of a series of Roots vacuum pump rotors. Processing quality is stable and reliable. After continuous improvement and perfection, the CNC system has functions such as real-time machining control, automatic graphics programming, complex curve and list curve fitting, programming, tool wear compensation, automatic tool setting, simulation and machining track tracking display. The CNC system of the planer is not only suitable for the NC transformation of small planer planers, but also for the NC transformation of other types of planers. ^[1]