Analysis of Development Trend of Domestic Punch Industry

The basic characteristics of punches produced by domestic punch manufacturers are mainly two, one is rigidity, which includes longitudinal rigidity - the curvature of the slider and the table and the elastic elongation of the frame; and the transverse rigidity - the influence of the eccentric load on the slider Horizontal shift. The second is the movement characteristics of the slider, including the verticality, parallelism, and straightness, which have a great influence on the accuracy of the product. The accuracy of the product is not only related to the press. It is related to the material, mold, lubrication, etc. It is not possible to consider only one factor. Considering the factors of the press, the accuracy of the thickness direction of the product is related to the longitudinal rigidity, and the deviation, bending, or parallelism is related to the characteristics of lateral rigidity and motion curve. Therefore, by improving these characteristics, product accuracy can be improved, die life can be extended, and the stability of production can be improved. According to the forming method, the forming speed, the productivity, etc., when selecting a punch press, these characteristics of the punch press must be considered. Depending on the drive mechanism, the mechanical presses are: the most widely used crank presses in press processing, the slowest one near the bottom dead center, and the slower slider speeds starting at a high position above BDC. And with a high torque capacity of the link punch.

When using a forging press, the crankshaft press is used when the productivity is the most important; if the pursuit of formability near the bottom dead point is to use the toggle punch; if the need for forming or blocking forging at a very high position is to use the connecting rod type punch. In order to realize cutting-free forming, the functional requirements of the punch press are getting higher and higher. The development trend of stamping machinery is developing towards high precision, high rigidity, suitable slider motion characteristics, intelligence, multi-directional movement, and even environmental protection.

Development Trend of Mechanical Presses 1. High rigidity and high performance of general purpose punch presses The C-shaped punch press used for general purpose machines also pursues high precision and high performance. This has led to the development of an integrated gantry punch press; AIDA connecting rod drive mechanism And a link press that is slow near SBD and SPM is not affected. This link punch press involves two eccentric links between the drive gear and the crankshaft. When the drive gear rotates, the crankshaft does not move at a constant speed due to the change in the link angle of the link. The difference between this link mechanism and other link mechanisms is that there are few connection points in the pressure receiving part and the overall clearance is small. The link-type mechanism has a higher torque capacity than a toggle-type mechanism and can achieve a higher position at the bottom dead point. The vertical link punch drive method is to add two vertical links and a fulcrum link in an ordinary toggle linkage mechanism, so that the link directly connected with the slider during processing is kept substantially vertical, so that the forming load Vertical transmission through the vertical link drive.

2. The common mechanical press machine is inclined to press on the slider because of the connecting rod, so that the slider is subject to a great bad lateral force. Therefore, this driving method has higher accuracy than the ordinary driving method and is more suitable for high-precision machining. . At the position 5mm above the bottom dead center, the slider of the ordinary toggle press is subject to a transverse force of approximately 10% of the forming force, while the vertical link press does not exceed 1%. This punching machine is suitable for requiring the upper and lower molds to be processed with a neutral height. Like the VL drive, the SL drive mode is a drive mode in which the lateral force acting on the slider is almost zero, but the stroke can be made longer, and it is suitable for starting at a higher position than the bottom dead point. Less extrusion processing. This linkage mechanism ensures that the link remains substantially vertical during operation. The vertical link punch press is mostly used for forward processing. However, in the complex shape forming process, the forward pass machining is used first, and the latter half is processed by a multi-position transfer composite method. Various types of transport devices are available, such as sucker type or jaw type three-dimensional servo multi-position transfer devices.

Development trend of CNC punching CNC punching machine has a CNC control system, which can arbitrarily set the motion mode and speed of the slider according to the needs of the processing method.

1. The screw-type digital punch press servo work machine uses an AC servo motor to drive the slider through the screw. The position of the lower dead point in the forming can be controlled by the position reading device to provide data to the position control device. Therefore, the thermal expansion and elastic deformation of the machine will not affect the accuracy of the product, adjust the most suitable way of slider movement and control the position of the dead point in an extremely small unit. Therefore, the high-precision high-performance cutting-free forming screw servo press adopts a hydraulic motor and an accumulator for torque control. The bottom dead point position control can reach micron level, which is an energy-saving and environmentally friendly machine. .

2. Crankshaft Servo Press Crank Press and AC servo motor combined CNC punch. This type of press uses a servo motor to replace the clutch brake and flywheel on the original punch. This kind of punching machine has the characteristics of the servo punch which can be arbitrarily set by the slider movement mode, and has the torque characteristics of the ordinary mechanical punching machine shown in FIG. 3 . However, its working energy will not decrease in the low speed area.

3. Double-action forming Press multi-action forming is a powerful tool for no-cut forming. Forging forging in cold forging is an example of controlling the plastic flow of a material by controlling the motion and time diagram of multiple punches and dies. The precision and formability of the product can be improved and even the number of processes can be shortened.

Re-formation can roughly be divided into two major categories: emphasis on the versatility of the punch press using double-acting molds; multiple-product molds can be assembled and disassembled easily using the punch press. Recently, not only in the forging process, but also in the diversification of the forming of the sheet metal and the forging and the improvement of the capability of the composite forming, the punching machine is required not only to have a multi-action performance but also to have a high versatility.

4. Occlusive forging presses The use of occlusal forging dies and universal forging presses has been widely used in the forming of star wheels and Phillips couplings. Its mold structure has occlusive function and coordination function. Other occlusion forging presses that can save piping time during mold assembly can be divided into two categories: these functions are all in the press and the upper and lower cylinders are on the punch and the coordinating mechanism is on the mold base in two forms.

5. Plate forging presses With the popularization of plate forging and forming, it is required that the forging presses can perform deep drawing or shorten the number of works. Therefore, sliders and table must be provided with cylinders. The original occlusive forging is almost always using high-capacity atmospheric pressure. In addition to the atmospheric pressure required for the forging work, the sheet forging also requires sequential actions, self-locking, and other functions.

6, the gear forming press with a helical gear press forming multiple hydraulic presses. There are a total of 5 hydraulic drive units for slide press drive, 2 sliders and 2 worktables. The initial stage of forming is the same as that of the inner ring of the atmospheric pressure ram type. The male mold is inserted into the concave tooth space in the occlusion and the material flows from the bottom to the initial shape. In this state, the core rises and the diameter of the core in the center of the material narrows. At this time, there is a new space in the inner diameter portion of the workpiece, and a new plastic flow can be generated, so that the increased pressure material can fill the toothed tip portion. The products processed by this method have a processing pressure of only 1300 MPa, and the dents and burrs of the toothed parts are extremely small. The gears that control the formation of the material flow by means of the double-action forming can reach JIS 3-4, which is very close to high-value-added non-cutting forming.