GB2150066A - Shears - Google Patents

Abstract

A shear particularly a cam- actuated, pendulum type flying shear comprises a frame formed by two side pieces 1,2 and cross head 3. At least one of the cross pieces is provided with an opening through which a cartridge 4 can be inserted in and removed from the frame. The cartridge has upper and lower arms positioned to lie above and below the material to be cut the installed condition forming a slot open at 15 and support the blades 5 and 7 respectively. <IMAGE>

Description

SPECIFICATION Shears A continuously moving metal product may be cut into lengths using a shear having upper and lower shear blades supported in a frame including side pieces surmounted by a cross head. The blades are mounted in respective blade holders, one of which is caused to reciprocate in the vertical sense relative to the frame by a drive mechanism, which may make use of cams for this purpose. The frame may be made to reciprocate and to rock in a pendulum-like manner during the shearing action. An example of such a shear is shown in German Patent 20 25 354. The two shear blades are subjected to considerable stresses and wear, and must be replaced frequently. It is also necessary to replace the blades if the cutting programme is to be changed. In order to replace the blades, the blade holders and blades must be removed from the frame to which they are firmly secured.This is a complicated and time-consuming operation, and it is also necessary to bring the product being cut to a halt, and to remove it from the shear.

The present proposal simplifies the blade replacement operation, and makes it unnecessary to interrupt the passage of the product through the shear. This is achieved by employing an open-ended cartridge in which the blades are supported. The cartridge may be likened to a U lying on its side, so as to have upper and lower arms, disposed respectively above and below the path to be followed by the product when the cartridge has been installed. As the cartridge is open at one end, it is possible for the blades to be exchanged, even in the case of a shear used in a continuous production line, for example an annealing line, at a suitable moment when the shear is not actually cutting, and even though the product is still present and possibly passing along the line. Interruptions in operation are thus avoided.

The cartridge is moved into and out of the frame from one side through a window in the side piece of that side. For this purpose, the cross head of the frame may be provided with a guide rail which cooperats with the upper arm of the cartridge. The upper blade holder is fixed in or integral with the upper part of the cartridge and is thus fixed on the frame by way of this interlocking connection of the guide rail and complementary guideway in the arm. Of course, the cartridge may be provided with the rail, and the cross head with a groove.

The lower blade holder may be made in two parts. In the first place, a first blade holder member in which the blade is fitted is guided for movement in vertical slots machined in lateral cheeks of the cartridge. Secondly, a second blade holder member mounted in the frame serves to transmit the cutting drive from the cams of the main driving shaft to the first blade holder member. A guide rail in the lower region of the frame may have a groove or slide track machined into the base of the lateral cheeks. Because drive must be transmitted to the lower blade holder, the lower blade holder cannot be bolted to the lower arm of the cartridge in the same way that the upper blade holder may be bolted to the upper arm. The lower arm therefore has a groove-shaped slide track extending the entire length of the cartridge.The lower blade holder is vertically reciprocable for which purpose it is guided internally in the lateral cheeks of the cartridge.

To give sufficient stability to the lower blade holder or the lower arm of the cartridge.

which is connected to the slide track merely by grooves machined in the base of the lateral cheeks, the lower arm of the cartridge is connected to that one of the two side pieces which is windowless. This is effected by a grooved block projecting from the upright and engaging in a groove in the lateral cheek. The block and groove are preferably conical in design to facilitate centring.

As the lower blade holder must have sufficient clearance for movement in the guide means, otherwise the clearance could have an adverse effect on the gap between the blades, it is further proposed that the lower blade holder be held on the guide side facing the rear of the blades in the vertical slots by means of magnetic force.

A particularly rapid blade replacement operation is made possible by using a movable cartridge support frame capable of being positioned on a stationary support in front of the shear and connected therewith. The frame supports a carrier movable transversely of the shear in the direction of gravel of the product to be cut. The carrier has two support locations for cartridges, and a spindle drive. The transportable structure enables a cartridge which has been equipped with new blades in the workshop to be brought up to the shear and remain there while operation continues.

The cartridge with the worn blades is pushed out from the shear frame into one support location of the carrier, which is then moved transversely so that the fresh cartridge comes into alignment with the window opening of the side piece. The spindle drive drives the cartridge into the shear. As soon as the new cartridge is located fully in the shear, the crane carries off the support frame with the superseded cartridge located therein.

In the drawings: Figure 1 is a front view of the shear; Figure 2 is a section through the shear on line Ill-Ill in Fig. 1; Figure 3 is a section on the line I-I in Fig.

1; Figure 4 is a section on the line ll-ll in Fig.

1; Figure 5 is a section on the line IV-IV in Fig. 1; Figure 6 is a front view of the cartridge with a transporting frame before installation in the shear; Figure 7 is a side view of the parts shown in Fig. 5 in the installation direction, as viewed from the right.

Referring to the drawings, a shear for continuously moving rolled metal product, for example strip or sheet, comprises a rockable frame having side pieces 1 and 2 and a cross head 3, supporting an upper blade 5 and a lower blade 7. The frame is supported by its main shaft 8 in stationary uprights, relative to which it may be made to swing back and forth in time with the moving rolled product by force applied through connecting rods 14 and 1 4a connected to the lower part of the frame. The two blades are caused to reciprocate in opposite directions by motion taken from the main shaft 8 using cams 9 and 9a and 10 and 1 Oa which are offset from each other. In this respect, the cams 9 and 9a cause the frame to rise and fall, and with it the upper blade, while the cams 10 and 1 0a cause the lower blade to reciprocate in the opposite sense to the upper blade.In accordance with the present proposal, the blades are supported in a cartridge 4. The cartridge 4 has a guideway extending the length of its uppermost edge and is mounted by means of the slide track 11 on the cross head 3. The cartridge is caused to reciprocate together with the frame. The lower blade holder 6 engages with the cams 10, 1 Oa by means of a slide rail 13 and the motion-transmitting articulations 12 and 1 2a and reciprocates relative to the cartridge.

The cartridge 4 has the form of a U lying on its side with an opening 15 at the end nearer the upright 1 so that it may be inserted and removed through the window 17 in the side piece 2 without fouling the rolled product 16. The upright 1 is consequently windowless. The lower cheek 4b of the cartridge 4 is centred in the direction of travel of the product by means of the groove 19 and the block 18 fixed on the windowless upright 1.

The slide rail 13 of the lower blade holder 6 is secured against tilting for the dismantled state of the cartridge 4 by means of the guide rails 21 and 21a or the groove and block 22 and 22a thereof.

Referring now to Figs. 6 and 7, posts 25 and 25a located adjacent the sidepiece 2 serve as supports and fixings for a transporta ble frame 24 capable of being carried on a crane to and from a workshop in which the cartridges are fitted with new or sharpened blades. The frame 24 has guide rails 27 and 27a along which a cartridge carrier 28 may be guided for movement parallel to the direction of movement of the rolled product under the action of threaded spindles. The carrier 28 has two guides 23, 23a which extend parallel to, and either of which may serve as an extension of, the guide rail 11.

One guide serves to receive the used cartridge from the shear, and the other to supprot the fresh cartridge to replace it, carriers 30 and 30a and spindle drives 31 and 31a being used in this connection.

Fig. 7 shows the used cartridge 4 with the replacement cartridge 26 on the two side rails 23 and 23a of the holding device 28 which can be moved on the guide rods 27 and 27a by means of spindles, with the dot-dash lines indicating the insertion position 29 for installing the replacement cartridge 26.

Claims (10)

1. A shear comprising a frame formed by two side pieces and a cross head, at least one of the side pieces having an opening through which a cartridge is insertable into and removable from the frame, the cartridge having upper and lower arms which, when the cartridge is installed in the frame, are positioned to lie above and below the material to be cut, each arm supporting a respective shear blade, the arms defining between them an open ended slot.

2. A shear according to claim 1, characterised in that an upper blade holder is fast or integral with the upper arm of the cartridge.

3. A shear according to claim 1 or 2, characterised in that a guideway extending the length of the upper arm of the cartridge receives a guide rail provided on the cross head of the frame.

4. A shear according to any of claims 1 to 3, characterised in that the lower blade holder is constituted by two parts, namely a first blade holder member equipped with the lower blade and guided for movement in vertical slots in lateral cheeks of the cartridge, and a second blade holder member mounted in the frame to transmit the cutting drive derived from cams of a main driving shaft to the first blade holder member.

5. A shear according to any of claims 1 to 4, characterised by a guide rail in the lower region of the frame for a guideway in the base of the lateral cheeks.

6. A shear according to any of claims 1 to 5, characterised by a connection between the lower arm of the cartridge and the windowless side piece.

7. A shear according to claim 5, characterised by a block arranged so as to project from one upright and engage in a groove in the lateral cheek.

8. A shear according to claim 7, characterised in that the groove and the block are conical.

9. A shear according to claim 4, characterised in that the lower blade holder, on the guide side facing the rear side of the blade, can be placed in the vertical slots by the magnetic force exerted by the magnets.

10. A shear substantially as hereinbefore described with reference to and as illustrated in the drawings.