RU2197391C1 - Power press drive - Google Patents

Abstract

FIELD: power presses for blanking and stamping parts from sheet materials. SUBSTANCE: power press drive includes drive eccentric shaft connected through eccentric bushings located on cranks of eccentric shaft for force engagement with it and connecting rods with press slide. Eccentric bushings are installed for alternating force engagement with eccentric shaft and connecting rods by means of step keys. Keyways with guides for step keys are made on internal and external surfaces of eccentric bushings, in plane of their symmetry, on side of maximum eccentricity. Keyways are also made on connecting rods internal surface and on diametrically opposite side of eccentric shaft cranks. Keys are located for displacement in installation and for locking in forced or free positions by threaded joints. EFFECT: simplified design of power press drive and reduced cost of equipment. 2 cl, 3 dwg

Description

 The invention relates to mechanical presses for cutting blanks and stamping parts from sheet material.

 A known press machine for cutting blanks from sheet material, containing a drive eccentric shaft connected via connecting rods to the slider of the press. When the drive eccentric shaft rotates, the reciprocating slide of the press is carried out at a constant value equal to twice the eccentricity of the drive shaft, which ensures the stamping process (press machine for cutting blanks from sheet material purchased by AVTOVAZ JSC from the Federal Republic of Germany HAYLUCK ROOS PRESSEN ").

 In this device, for various modifications of the dies in accordance with the stroke size of the press slide, various modifications of the press machines are required. In the manufacture of new dies, the process of setting them up is required, for which a press with a slider stroke corresponding to the stamp is used, which requires the removal of the corresponding press from the existing production and its use for the adjustment work on dies. For each modification of the dies, which is determined by the stroke of the press slide, the adjustment process provides the press load by no more than 30 percent in accordance with the production program of dies. To ensure the adjustment of three modifications of the dies, determined by the stroke of the press slide, it is necessary to maintain three corresponding presses with a 30 percent load of each press, which narrows the technological capabilities of the press and increases the cost of equipment.

 The closest in technical essence to the claimed technical solution is a device for regulating the stroke of the press ram, containing eccentric bushings mounted on crank shafts of the shaft with the possibility of rotation and power engagement with them, interconnected through connecting rods with the press ram (RF Patent 2003473, IPC class B 30 V 15/14).

 This device is taken by us as the closest analogue.

 The disadvantage of this device is that it includes a complex mechanism with a large number of parts to ensure the possibility of hard connection and disconnection of the drive shaft with eccentric bushings and its rotation by the required angle to change the stroke of the press slide. In addition, this design becomes practically unacceptable for use in heavy presses with a large slide force (more than 100 tons) due to the corresponding increase in the weight and size of large parts included in the design, such as eccentric bushings and coupling halves, and the need to move and fix them .

 The technical solution is aimed at simplifying the design of the device and reducing the cost of equipment.

 To solve the problem in the drive of a mechanical press, including a drive eccentric shaft, connected through eccentric bushings placed on the crank necks of the eccentric shaft with the possibility of power engagement with it, and connecting rods with a slider press, the bushings are installed with the possibility of alternate power engagement with the eccentric shaft and connecting rods by means of stepped dowels, while in the plane of symmetry of the eccentric bushings on their inner and outer surfaces and on the inner surface of the connecting rods with Oron greatest eccentricity of sleeves, as well as the eccentric shaft on the crank journals on diametrically opposite sides keyways formed under the stepped dowel, wherein the keyways on the eccentric sleeves are made with the guide.

 In this case, the keys are placed with the possibility of installation movements and fixation in the power and free positions by threaded connections.

Figure 1 shows a General view of the drive of a mechanical press "
Figure 2 is a view and figure 1.

 Figure 3 is a section bB in figure 1.

 The drive of the mechanical press contains a drive eccentric shaft 1, connected through connecting rods 2 to the slider of the press 3. On the crank necks 4 of the eccentric shaft 1 with the possibility of alternate power engagement with the eccentric shaft 1 and the connecting rods 2 mounted eccentric bushings 5. In the plane of symmetry of the eccentric bushings 5 from the side of the greatest eccentricity, on their outer and inner surfaces, respectively, keyways 6 and 7 are made with guides 8, mating alternately with keyways 9 made with a diameter of opposite sides of the crank necks 4 of the eccentric shaft 1 and with keyways 10 made on the inner surfaces of the connecting rods 2 by means of step keys 11 and 12 with guides 13 placed with the possibility of installation movements in the guides 8 of the grooves 6 and 7 of the eccentric bushings 5 and fixing them in force and free positions with threaded connections made in the form of screws 14 and plates 15. On the crank necks 4 of the eccentric shaft 1, keyways 16 are made diametrically opposite to the grooves 9.

 The device operates as follows.

 Before turning on the drive of the mechanical press, the required stroke of the press slider is set by removing one of the keys 11 or 12 from the power mesh with the connecting rod 2 or with the eccentric shaft 1 and insert the other key into the corresponding power mesh with their subsequent fixation by means of screws 14 and plates 15. This changes the eccentricity of the eccentric shaft 1, which provides a corresponding change in the stroke of the slider of the press.

 In the initial position, the keys 11 are inserted into the keyways 6 and 10 and secured with screws 14 and plates 15, and the keys 12 are taken out of the keyways 7 and 9. The eccentric bushings 5 are in power engagement with the connecting rods 2 and the stroke of the slide 5 is determined by the eccentricity eccentric shaft 1.

 When the press is turned on, the eccentric shaft 1 is driven into rotation, as a result of which the press slider 3 is driven through the eccentric bushings 5 and the connecting rod 2 rigidly connected to them.

 If it is necessary to change the stroke of the press slide, the press is stopped. Then, the keys 11 are removed from the keyways 6 and 10, and the keys 12 are inserted into the keyways 7 and 9, followed by their fixing with screws 14 and plates 15. In this case, the eccentric sleeve 5 is rigidly connected to the eccentric shaft 1 and the stroke value of the slide takes the greatest value, determined by the sum of the eccentricities of the eccentric shaft and the eccentric sleeve.

 To set the third stroke value of the press slide, the keys 12 are removed from the keyways 7 and 9, and the keys 11 are inserted into the keyways 6 and 10 with their subsequent fixation, after which the eccentric shaft is rotated 180 degrees and the slide moves to the bottom dead center, the eccentric bushings 5 are rotated together with the shaft until the grooves 16 coincide with the keyways 7, then the keys 12 are inserted into the keyways 7 and 16, and the keys 11 are removed from the keyways 6 and 10. In this case, the eccentric shaft 1 is in power engagement with the eccentric with new bushings 5 and the minimum stroke of the press slide is obtained.

 By repeating the above steps, when changing the press, any of the three specified values of the stroke of the press slider is set.

 The use of the proposed technical solution eliminates the need for the presence and maintenance of three presses for setting dies, the modifications of which require three different stroke sizes of the press slider, which reduces the costs required for the manufacture and purchase of two additional presses, as well as for their placement, maintenance and operation.

Claims (2)

 1. The drive of the mechanical press, including the drive eccentric shaft, connected through eccentric bushings placed on the crank necks of the eccentric shaft with the possibility of power engagement with it, and connecting rods with the slider of the press, characterized in that the eccentric bushings are installed with the possibility of alternate power engagement with the eccentric shaft and connecting rods by means of stepped dowels, while in the plane of symmetry of the eccentric bushings on their inner and outer surfaces and on the inner surface of the connecting rods side of the greatest eccentricity of sleeves, as well as the crank journals of the eccentric shaft diametrically opposite sides of the keyways formed under the stepped dowel, wherein the keyways on the eccentric sleeves are made with the guide.  2. The mechanical press drive according to claim 1, characterized in that the stepped keys are placed with the possibility of installation movements and fixation in the power and free positions by threaded connections.

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