RU2200648C2 - Flying shears for rolled stock - Google Patents

Abstract

FIELD: equipment used, for example, for cutting rolled coiled and elongated blanks by measured lengths. SUBSTANCE: flying shears have housing, drive eccentric shaft with large and small eccentrics supporting respectively connecting rods and support with upper cutter. Traverse bar with lower cutter is mounted in guides of support with possibility of reciprocation motion and it joins lower portions of connecting rods. Shears are provided with mechanisms for balancing support; said mechanism are connected with connecting rods and with traverse bar by means of articulation joints. Flying shears are also provided with crank mechanism mounted in housing and having crank jointly coupled with support at one side through shackle and at other side - through flexible pulling member. Crank radius is equal to eccentricity value of large eccentric and it is directed to the same side. EFFECT: lowered dynamic loads, enhanced reliability, efficiency and cutting quality of flying shears. 3 dwg

Description

 The invention relates to equipment used in modular lines and mills for cutting rolled and lengthy rolled products to measured lengths in the rolling production of ferrous and non-ferrous metallurgy plants or at enterprises that process the rolled strip into sheet products.

 Flying scissors are known containing a cutting mechanism located on the bed in the form of a lower knife holder mounted on a drive eccentric shaft with a lower knife connected to the lower knife holder by hinges of the upper knife holder with the upper knife and two rods, one ends of which are mounted on the eccentrics of the drive eccentric shaft, and the other connected with an upper knife holder and equipped with two connecting rods, while each of the connecting rods is connected to the bed and to the lower knife holder, the latter is mounted on an additional body eccentrics of the drive eccentric shaft, and the position of each of the connection points of the rods with the upper knife holder is determined by the specified maximum vertical distance between the cutting edges of the upper and lower knife (RF patent 2047428, 23 D 25/06, 1992).

 The disadvantages include - the complexity of the design, the presence of a large number of articulated joints, and as a result - the complexity of manufacturing and repair, unreliability in work.

 Closest to the invention are flying shears for rolling, containing a bed, an eccentric drive shaft with large and smaller eccentrics, on which are respectively mounted the connecting rods and the caliper with the upper knife, as well as the yoke with the lower knife, mounted in the guide rails with the possibility of reciprocating movements and connecting the lower parts of the connecting rods (RU 2019 366 C1, B 23 D 25/02, 09/15/1994).

 The disadvantages include the lack of balancing of the upper caliper, causing knocks in the mechanism during operation as a result of alternating loads on the hinges of the suspension of the upper caliper to the eccentric shaft, as well as the occurrence of additional dynamic loads on the shear mechanisms caused by the presence of a two-parallelogram mechanism consisting of two cases and eight earrings pivotally attached to it, making complex oscillating movements during operation. All this leads to frequent breakdowns, repairs, and as a result to unreliability during operation and to a decrease in the performance of the units as a whole.

 The technical problem solved by the invention is to create flying shears, simple in design with less dynamic loads, for cutting strip, high profile rolled products and bent profiles into measured lengths, increasing reliability, productivity and cutting quality.

 To solve the technical problem in the known design of flying shears for cutting rolled products containing a bed, an eccentric drive shaft with a larger and smaller eccentric, on which rods and a support with an upper knife, and also a beam with a lower knife, are mounted in the caliper guides with the possibility of return - translational movement and connecting the lower parts of the connecting rods, while the scissors are caliper balancing mechanisms connected to the connecting rods and the traverse by means of hinges, as well as fixed m on the frame a crank mechanism in the form of a crank, associated with a support on the one hand hingedly by shackle and, on the other - a flexible traction body, the crank radius equal to the eccentricity of the eccentric more and coincides with the direction.

 In FIG. 1 shows the kinematic diagram of flying shears for cutting; figure 2 is a transverse section of scissors; figure 3 is a section aa in figure 2.

 Flying shears contain a frame 1, drive 2, an eccentric drive shaft 3 with large eccentrics 4 and smaller eccentrics 5, suspended on large eccentrics 4, a support 6 with a knife holder 7 fixed thereto with an upper knife 8, suspended on smaller eccentrics 5 through connecting rods 9, a crosshead 10 located in the guides of the caliper 6 with the possibility of reciprocating movement and carrying the lower knife 11. On the bed 1 the crank mechanism 12 is fixedly fixed, connected to the caliper 6 on one side through the earring 13, and on the other side they are through sprockets 14 and 15 and a flexible traction member 16 for transmitting rotation from the eccentric shaft 3 to the crank mechanism 12, while the radius of the crank 17 is equal in magnitude and direction to the larger eccentricity 18 of the eccentric shaft 3. The caliper is equipped with balancing mechanisms 19 connected by hinges 20 with connecting rods 9 and traverse 10.

 The upper knife 8 may be parallel to the lower knife 11, inclined to it or "chevron", as shown in Fig.3.

 Scissors work as follows.

 As a rule, scissors work in the start mode for each cut. For cutting rolled products into short lengths, continuous operation at variable speed can be applied. When the drive 2 is turned on, rotation is initiated to the eccentric shaft 3 and, through the flexible traction member 16, to the crank mechanism 12 with the same angular and peripheral speeds. Due to the articulation of the support 6 through the earring 13 with the crank mechanism 12, the support 6 with the upper knife 8 performs plane-parallel movement along the radius equal to the eccentricity 4. Since the crosshead 10 is connected with the support 6 using flat vertical guides, it also moves horizontally by double eccentricity 4. At the same time, due to the connection of the crosshead 10 with smaller eccentrics 5 by means of connecting rods 9, additional vertical movement is communicated to it. The result is a circular plane-parallel movement of the upper knife with the path of the cutting edges 21 and plane-parallel movement of the lower knife with the path of the cutting edge 22, and part of the path of the lower knife during the cut is almost a straight line, i.e. bending of the rolled up during the cut does not occur.

 As a result of joint movements of the knives, the rolled products are cut 23. With a further rotation of the shaft 3, the knives diverge, skipping the rolling. During the operation of the scissors, the balancing mechanisms 13 of the caliper's own mass 6 constantly press it from the bottom to the eccentric shaft 3, transferring the alternating load on the shaft 3 to the pulsating one, thereby eliminating the knocks in the mechanism.

 The shaft stops in a strictly defined position, from which the next cycle of cutting of rolled products begins according to the signal of the measured cutting system (measuring the length of the rental).

 The frequency of rotation of the eccentric shaft 3 is selected so that the linear speed of the horizontal movement of the knives 8 and 11 is equal to the speed of the rolling.

 The use of the invention allows to increase the reliability of scissors by simplifying the design, reducing the number of elements making complex oscillatory movements, and as a result of this increases the productivity of units where the proposed flying scissors are used. The introduction of balancing mechanisms into the scissors design allows to reduce shock loads, reduces knocks during scissors operation, increases the smoothness of the caliper movement, and as a result, the quality of metal cutting is improved.

Claims (1)

 Flying shears for cutting rolled products, containing a bed, a drive eccentric shaft with a larger and smaller eccentric, on which are respectively mounted the connecting rods and a support with an upper knife, as well as a yoke with a lower knife, mounted in the support rails with the possibility of reciprocating movement and connecting the lower parts connecting rods, characterized in that they are equipped with caliper balancing mechanisms connected to the connecting rods and traverse by means of hinges, as well as a crank mechanism fixed to the bed in the form of a crank connected to the support on the one hand pivotally through the earring, and on the other through the flexible traction organ, and the radius of the crank is equal to the eccentricity of the larger eccentric and coincides with it in direction.

Images