Title of Invention

"SWIVEL DEVICE WITH CANTILAVER ARM FOR A TAPHOLE PLUGGING GUN"

Abstract

A device for swivelling an operational element (16) between a home position and an operational position, comprises a supporting structure (18) supporting in a swivelling manner a cantilever arm (20). A swivel arm (38) with an actuator drive (42) is mounted with one end in a swivelling manner in the supporting structure (18), and is connected with the other end in jointed manner with a linear drive (28). The latter is connected with its second end in jointed manner with the cantilever arm (20). Due to the fact that the swivel axis (40) of the swivel arm (38) is located at a certain distance from the swivel axis (22) of the cantilever arm (20), it is possible to increase the lever arm, with which the linear drive (28) transmits its force onto the cantilever arm (20) in the operational position. The eccentric mounting of the swivel arm (38) also allows to switch the actuator drive (42) of the swivel arm (38) in the operational position of the cantilever arm (20) largely free of force. The swivel device is particularly well-suited for tap hole plugging machines.

Full Text

SWIVEL DEVICE WITH CANTILEVER ARM The invention relates to a swivel device with a cantilever arm for swivelling an operational element between a home position and an operational position. Such a device is used, for example, for swivelling a tap hole plugging gun from a home position into an operational position in front of the tap hole of a blast furnace, as well as for the subsequent pressing of the plugging gun against the tap hole. A traditional swivel device for a tap hole plugging gun comprises, in a manner known per se, a fixed supporting structure and a cantilever arm. The latter has one of its two ends mounted in a swivelling manner in the supporting structure. In most cases, hydraulic cylinders are used to swivel the cantilever arm. The swivelling range of such a swivel device should, as a rule, be as great as possible, in order to be able to swivel the plugging gun as far as possible out of the range of the tapping channel. In addition to this, it must be considered that modern plugging guns are operating with increasingly high plugging pressures. As a result, the swivel device which is intended to press the plugging gun against the tap hole must also be designed for ever greater pressing forces. In US-A-3,765,663 two different embodiments of a swivel device for a tap hole plugging gun are described. In the first embodiment, a hydraulic cylinder is arranged between a fixed lever arm on the supporting structure of the cantilever arm and the rear end of the cantilever arm. The swivelling angle is limited with this device to approximately 90°, in order to be able to achieve a sufficiently great pressure force. For extending the swivelling range beyond 90°,US-A-3,765,663 proposes the arrangement of a lever system between the hydraulic cylinder and the supporting structure. This lever system consists of a U-shaped element, one end of which being secured in a jointed manner to the supporting structure, and the other end of said element being connected in a jointed manner by means of a connecting rod to the cantilever arm. The hydraulic cylinder is arranged between the supporting structure and the U-shaped element. In order to extend the swivelling angle beyond 90°, it has been suggested to use swivel devices with several hydraulic cylinders. DE-A-2035697 discloses for example a swivel device for a tap hole plugging gun which has a main cylinder for generating the swivelling movement and a smaller ancillary cylinder for overcoming the dead centre of the main cylinder. The main cylinder is arranged between a first lever arm at the rear end of the cantilever arm and a first fixed lever, which projects from the supporting structure of the cantilever arm. The auxiliary cylinder swivels the cantilever arm beyond the dead centre of the main cylinder. A hydraulic switch alters the stroke direction of the double-acting main cylinder when the dead centre is overrun. US-A-4,544,143 discloses a swivel device for a tap hole plugging gun which has two hydraulic cylinders of equal size. The first hydraulic cylinder is mounted between a fixed point on the supporting structure of the cantilever arm and a swivel frame. This swivel frame is mounted in a swivelling manner on the supporting structure, wherein its swivel axis is co-axial to the swivel axis of the cantilever arm. The second hydraulic cylinder is arranged between the swivel frame and the rear end of the cantilever arm. The two hydraulic cylinders are actuated either simultaneously or in a specific sequence. They both contribute their share to covering the swivel range of the cantilever arm. In the operational position, the first hydraulic cylinder must transmit onto the supporting structure the movement of force exercised by the second hydraulic cylinder on the swivel frame, when pressing the plugging gun against the tap hole. As the lever arms of both hydraulic cylinders are approximately of the same size, both cylinders are designed to be of equal strength. It is likewise to be noted that the lever arm which is available to the second hydraulic cylinder for transferring its force onto the^antilever arm is not influenced by the position of the swivel frame. It is an object of the present invention to improve the transfer of forces in the swivel device known from US-A-4, 544, 143. This object is achieved by means of a swivel device according to Claim 1. Such a swivel device comprises, like the device disclosed in US-A-4,544,143: a cantilever arm for supporting an operational element, a supporting structure in which the cantilever arm has one end mounted in a swivelling manner a swivel axis; a first linear drive as a rule a hydraulic cylinder, to swivel the cantilever arm between its home position and its operational position, wherein the linear drive is connected to the cantilever arm by means of a first rotational joint; a swivel arm, which is mounted with one end in the supporting structure so as to be capable of swivelling about a swivel axis, wherein the linear drive is connected by means of a second rotational joint to the free end of the swivel arm; and an actuator drive for swivelling the swivel arm relative to the supporting structure. According to the invention, the swivel axis of the swivel arm is not, as described in US-A4,544,143, located co-axially to the swivel axis of the cantilever arm, but at a certain distance from it. In other words, the swivel arm is mounted eccentrically to the cantilever arm. Due to this eccentric mounting of the swivel arm, it will be possible to increase the lever arm with which the linear drive exercises its force on the cantilever arm. By means of an adequate swivelling of the eccentrically-mounted swivel arm, it will also be possible to switch the actuator of the swivel arm largely free of force, when the cantilever arm is in the operational position. In other words, the swivel arm can be swivelled into a position in which the linear drive does not exercise any moment of force onto the actuator drive, when transferring its force onto the cantilever arm. When the cantilever arm is swivelled from its home position into its operational position, the hydraulic cylinder of the cantilever arm and the actuator drive of the swivel arm are actuated either simultaneously or in succession. The actuator of the swivel arm in the present invention also contributes its share to covering the swivel range of the cantilever arm. In comparison with the swivel device from US-A- 4,544,143, a swivel device according to the invention can, however,bemore compact and cheaper, wherein neither the swivelling range nor the pressure force transferred on to the operational element need to be reduced. In an advantageous embodiment of the invention, the swivel arm is capable of being swivelled by means of its actuator into an operational position, in which, in the operational position of the cantilever arm, the second rotational joint of the linear drive, is located in the immediate proximity of a plane, which contains the swivel axis of the swivel arm and the centre of the first rotational joint of the linear drive. In this position, the swivel arm should absorb no moment of force, or only a small moment of force, when the linear drive is actuated, so that the actuator must apply no force, or only a small force, in order to hold the swivel arm in its operational position. The actuator drive of the swivel arm can, accordingly, be designed substantially weaker than the linear drive of the cantilever arm. In an alternative embodiment, the swivel arm can be swivelled into an operational position by its actuator drive, in which , in the operational position of the cantilever arm, the second rotational joint of the linear drive is located on the other side of a plane which contains the swivel axis of the swivel arm and the centre of the first rotational joint. In other words, the second rotational joint of the linear drive is swivelled beyond the position in which the swivel arm is free of any moment of force when the linear drive is actuated. It will be noted that during the swivelling operation, the moment of force which is exerted on the swivel arm changes its effective direction. In this embodiment of the swivel device, the supporting structure advantageously has an abutment, with which the swivel arm is in contact in the operational position. This abutment absorbs the moment of force which is introduced into the swivel arm when the linear drive is actuated, with the result that the actuator drive is entirely relieved. As an alternative to the abutment, the actuator drive may have an integrated limit stop, which defines the operational position of the swivel arm. The swivel arm and its actuator drive are advantageously designed in such a way that the distance between the swivel axis of the cantilever arm and a straight line joining the centres of the two rotational joints of the linear drive increases, when the swivel arm is swivelled into its operational position. As a result of this, the lever arm with which the force of the linear drive is transferred onto the swivelling cantilever arm is increased. Because the pressure force, which is transferred through the swivel device onto the operational element, is proportional to the moment of force which is transferred by the linear drive onto the cantilever arm, the pressure force consequently increases in proportion to the lever arm referred to above. In other words, with a compact linear drive it is possible to generate very high pressure forces in the device as proposed. The actuator drive is preferably a second linear drive, as a rule a hydraulic cylinder, which is connected in a jointed manner on one side to a fixed point of the supporting structure and, on the other side, to the swivel arm. This second linear drive can be designed substantially smaller than the first linear drive (i.e. it can feature a substantially smaller diameter). This makes it possible to achieve not only a more compact and cheaper design for the swivel device, but also to reduce the oil consumption of the swivel device. It remains to be noted that the actuator drive of the swivel arm can, if appropriate, be a rotary drive, such as, for example, an electric or hydraulic swivel motor. In a preferred embodiment of the device according to the invention, the swivel arm features a home position in which the second rotational joint of the linear drive is arranged in such a way that, in the home position of the cantilever arm, the first linear drive lies essentially parallel to the cantilever arm. As a result of this, the swivel device becomes particularly compact in the home position, and . therefore requires little space for erection. Finally, it remains to be noted that a swivel device in accordance with the invention can be advantageously used in a tap hole plugging machine. Accordingly there is provided swivel device for swiveling an operational element between a home position and an operational position, comprising: a cantilever arm for supporting the operational element; a supporting structure in which the cantilever arm has one end mounted in a swiveling manner about a swivel axis; a first linear drive for swiveling the cantilever arm between its home position and its operational position, wherein a first rotational joint connects the linear drive to the cantilever arm. a swivel arm which is mounted with one end in the supporting structure, so as to be capable of swiveling about a swivel axis, wherein the linear drive is connected by means of a second rotational joint to the free end of the swivel arm; and an actuator drive for swiveling the swivel arm relative to the supporting structure; characterized in that the swivel axis of the swivel arm is located at a distance from the swivel axis of the cantilever arm, so that the swivel arm is mounted eccentrically to the cantilever arm. Embodiments of the invention are described in greater detail on the basis of the appended drawings. These show: Figure 1: A plan view of a tap hole plugging machine with a swivel device according to the invention, in the home position in front of the blast furnace; Figure 2: The same view as in Figure 1, in which the swivel device is represented in schematic form; Figure 3: A plan view of the tap hole plugging machine from Figure 1, in an intermediate position; Figure 4: The same view as in Figure 3, in which the swivel device is represented in schematic form; Figure 5: A plan view of the tap hole plugging machine from Figure 1, in an operational position at the tap hole; Figure 6: The same view as in Figure 5, wherein the swivel device is shown in schematic form; Figure 7: The same view as in Figure 6, with a design variation of the swivel device. In Figure 1, a tap hole plugging machine 10 according to the invention can be seen in its home position, in front of a blast furnace 12, which is schematically indicated by a circular arc. This tap hole plugging machine 10 consists essentially of a swivel device 14 according to the invention and a known tap hole plugging gun 16. The latter is not described here in any further detail. The swivel device 14 includes a mounting pedestal, which forms a supporting structure 18 for a cantilever arm 20. Instead of being set on the ground, this supporting structure 18 can of course also be suspended. The cantilever arm 20 has one end mounted in a swivelling manner about a swivel axis (22) in the supporting structure 18. In Figure 1, the position of the swivel axis of the cantilever arm 20 in the supporting structure 18 is shown by the reference number 22. This axis 22 is in most cases slightly inclined towards the blast furnace 12, relative to the vertical. At the free end of the boom 20 thejapjnole plugging gun 16 is suspended in a swivelling manner at the free end of the cantilever arm 20. The position of the swivel axis of the tap hole plugging gun 16 in the cantilever arm 20 is shown by the reference number^ 24. In a known manner, a control rod 26 is connected in jointed fashion to the supporting structure 18 and to the rear end of the tap hole plugging gun 16. This control rod 26 determines the orientation of the tap hole plugging gun 16 as a function of the swivelling angle of the cantilever arm 20. A hydraulic cylinder 28, which in Figure 1 is located along the length of the cantilever arm 20, allows to swivel the cantilever arm 20 about its swivel axis 22. One end of this hydraulic cylinder 28, which is shown in the embodiment as a piston end 30, is connected to the front end of the cantilever arm 20 by means of a first rotational joint 32. The cantilever arm 20 advantageously has a lateral projection 34, to which the first rotational joint 32 is secured (see Figure 2). The second end of the hydraulic cylinder 28, which in the embodiment shown is the foot of the cylinder, is connected by means of a second rotational joint 36 to a swivel arm 38. The latter is mounted in a swivelling manner to a fixed point on the supporting structure 18. The location of the swivel axis of the swivelling arm 38 in the supporting structure 18 is shown in the Figures by the reference number 40. It is an important feature of the present invention that the swivel axis 40 of the swivel arm 38 is located at a certain distance from the swivel axis 22 of the cantilever arm 20. In other words, supporting structure 18, cantilever arm 20, swivel arm 38 and hydraulic cylinder 28 form from a kinematic point of view a four-member drive assembly (18, 20, 38, 28) with four rotational joints (22, 32, 36, 40). A second, considerably smaller hydraulic cylinder 42 is connected in a jointed manner on the one side to a fixed point 46 on the supporting structure 18, and, on the other side, to the swivel arm 38. This hydraulic cylinder 44 makes it possible for the swivel arm 38 to be swivelled relative to the supporting structure 18, wherein, in the drive assembly (18, 20, 38, 28), the relative position of the I hydraulic cylinder 28 to the cantilever arm 20 changes. It follows that the lever ^arm of the hydraulic cylinder 28 relative to the swivel axis 22 of the cantilever arm J20 changes too. j In Figures 1 and 2, both hydraulic cylinders 28 and 42 are shown in their minimum length, i.e. the piston in which their rods are retracted. It can be seen that the swivel device 12 is extremely compact in this position, and requires little space in comparison with known machines. On the other hand, however, in this position the preconditions for a moment of force transfer from the hydraulic cylinder 28 onto the cantilever arm 20 are extremely unfavourable. In fact, the lever arm X1 for the force transfer, i.e. the distance between the swivel axis 22 of the cantilever arm 20 and the straight line 48, which connects the centres of the two rotational joints 32 and 36 of the hydraulic cylinder 28, is relatively small. In Figures 3 and 4, the tap hole plugging machine 10 is shown in an intermediate position between the home position and the operational position. By making a comparison between Figure 4 and Figure 2, it can be seen that, in the interim, only the piston rod of the hydraulic cylinder 42 has been moved out. The swivel arm 38 has been swivelled in the direction of the arrow 50, about its swivel axis 40, from its home position into what is referred to as an operational position. Because of this swivel movement of the swivel arm 38, the cantilever arm 20 was swivelled out from its home position, shown in Figures 1 and 2, into the intermediate position in as shown in Figures 3 and 4. In other words, the small hydraulic cylinder 42 has swivelled the swivel arm 20 over an angle of about 40° about its swivel axis 22. In Figure 4 it can further be seen that, due to the swivel arm 38 being swivelled into its operational position, the lever arm X2, which, in the position in Figure 4, is to be taken into consideration for a moment of force transfer from the hydraulic cylinder 28 onto the cantilever arm 20, is substantially greater than the corresponding lever arm X1 in Figure 2. In Figures 5 and 6, the tap hole plugging machine 10 is shown in its operational position. In this operational position, it is intended that the tap hole plugging gun 16 is pressed tight against a tap hole 51 at the blast furnace 12 by the cantilever arm 20. It must be emphasised in particular that in this operational position the second rotational joint 36 of the hydraulic cylinder 28 is located in the immediate proximity of a plane 48", which contains the swivel axis 40 of the swivel arm 38 and the centre of the first rotational joint 32 of the linear drive 28. This guarantees that the hydraulic cylinder 42 of the swivel arm 38 does not need to accommodate any components of the reaction force, at least in the ideal situation. In practice the hydraulic cylinder 42 may have to accommodate small force components, if the hydraulic cylinder 28 generates the pressure required at the plugging gun 16 while being supported by the supporting structure 18. In fact, if the centres of the two rotational joints 32 and 36 of the hydraulic cylinder 28, and the swivel axis 40 of the swivel arm 38, are all located precisely in the plane 48", the reaction force is conducted exclusively through the swivel arm 38, via the rotational joint 40, directly into the supporting structure 18. In other words, the hydraulic cylinder 28 does not exercise any torque on the swivel arm 38 in this position, since the line of effect of the force runs precisely through the swivel axis 40 of the swivel arm 38. In practice, however, slight alignment errors of the swivel arm 38 and the hydraulic cylinder 28 in the operational position of the cantilever arm 20 cannot be avoided. Such alignment errors may be caused, for example, by the fact that the swivel angle of the cantilever arm 20 may change slightly from the home position into the operational position. In order to take account of these alignment errors, the hydraulic cylinder 42 is preferably designed in such a way that it is capable of compensating for a residual moment which is induced in the swivel arm 38 by the hydraulic cylinder 28, when the plugging gun 16 is pressed against the tap hole. In order to be able to adapt the final position of the swivel arm 38 to different swivel angle values of the cantilever arm 20, the stroke of the hydraulic cylinder 42 is advantageously designed so as to be adjustable. To achieve this, the hydraulic cylinder 42 may, for example, have a mechanically adjustable limit stop. However, if the swivel angle of the cantilever arm 20 must be changed too much, it is advisable to use a sensor to detect the compensation error of the swivel arm 38 and to automatically adjust the stroke of the hydraulic cylinder 42 until the alignment error has been eliminated; i.e. until the centres of the two rotational joints 32 and 36 of the hydraulic cylinder 28 and the swivel axis 40 of the swivel arm 38 are located in a plane 48". Such an adjustment is schematically represented in Figure 6. Reference number 52 indicates an angle sensor, which measures the angle between the swivel arm and the hydraulic cylinder 28 and passes this value on to a controller 54. The output signal 56 from this controller 54 is then used for controlling the stroke of the hydraulic cylinder 42. For the purpose of adjusting the hydraulic cylinder 42, the hydraulic cylinder 28 must, if necessary, be shortly relieved. In Figure 6, the distance X3 represents the lever arm which is to be taken into account for the transfer of the moment of force of the hydraulic cylinder 28 onto the cantilever arm 20. It may be noted that this lever arm X3 is relatively large in comparison with known tap hole plugging machines. The hydraulic cylinder 28 could, as a result, be designed smaller than usual, without the pressure force being reduced. It should be emphasised in particular that this increased lever arm X3 is obtained without any negative effect on the compactness of the machine in the home position. With regard to the function of the machine, it should further be noted that under normal circumstances it is first the small hydraulic cylinder 42 which is actuated, and only then the large hydraulic cylinder 28, when the cantilever arm is swivelled from the home position into the operational position. It is, however, likewise possible to actuate both hydraulic cylinders 28, 42 simultaneously, or to actuate the small hydraulic cylinder 42 only shortly before reaching the operational position. In Figure 7, a further possible embodiment of the swivel device according to the invention is shown in the operational position. If Figure 7 is compared with Figure 6, it can be seen that the second rotational joint 36 of the linear drive 28 lies on the far side of the plane 48", which contains the swivel axis 40 of the swivel arm 38 and the centre of the first rotational joint 32 of the linear drive 28. In this position, the swivel arm 38 is in contact with an abutment 60 of the supporting structure 18. In this embodiment of the swivel device, the actuator drive 42 does not absorb any reaction forces in the operational position of the cantilever arm 20, when transferring the moment of force via the hydraulic cylinder 28 onto the cantilever arm 20. Reaction forces are in fact introduced via the rotational bearing 40 or the abutment 60 respectively directly into the supporting structure 18. As an alternative, the position of the swivel arm 38 according to Figure 7 could also be secured by an internal stroke limitation arrangement of the hydraulic cylinder 42; i.e. without an additional abutment 60 on the supporting structure. In this case, the hydraulic cylinder 42 would have to accommodate tensile forces , however, during the transfer of the moment of force via the hydraulic cylinder 28 onto the cantilever arm 20. In the described swivelling device, the two hydraulic cylinders 28, 42, demonstrate their minimum length in the home position. The swivelling of the cantilever arm 20 from its home position into its operational position is accordingly effected by the extension of their piston rods. It remains to be noted that it is easily possible for the swivel device to be re-engineered in such a way that the swivelling of the cantilever arm 20 from its home position into its operational position can be effected by the retraction of the piston rods of both hydraulic cylinders. With regard to the oil consumption of the swivel device, the following points should be noted. For a specific swivel angle of the cantilever arm 20, the oil consumption of the weaker hydraulic cylinder 42 is naturally far less than the oil consumption of the hydraulic cylinder 28. The total oil consumption for the swivelling of the cantilever arm 20 from its home position into its operational position is, as a consequence, sharply reduced by the swivelling capacity of the hydraulic cylinder 42. It follows that the hydraulic cylinder 28 may have a larger diameter, without increasing the overall oil consumption for the same swivel angle, in comparison with known swivel devices. It follows that the pressure force of the swivel device can be increased by choosing a stronger hydraulic cylinder 28, without substantially increasing the oil consumption of the swivel device. In this context it is to be noted that a smaller oil consumption implies not only savings in costs with regard to the hydraulic system but in most cases further achieves a lower energy consumption. In conclusion it is noted that the described swivel device is of particular advantage if a large swivel angle and a high pressure force are required. WE CLAIM:- 1. Swivel device for swiveling an operational element (16) between a home position and an operational position, comprising: a cantilever arm (20) for supporting the operational element (16); a supporting structure (18) in which the cantilever arm has one end mounted in a swiveling manner about a swivel axis (22); a first linear drive (28) for swiveling the cantilever arm (20) between its home position and its operational position, wherein a first rotational joint (32) connects the linear drive (28) to the cantilever arm (20). a swivel arm (38) which is mounted with one end in the supporting structure (18), so as to be capable of swiveling about a swivel axis (40), wherein the linear drive (28) is connected by means of a second rotational joint (36) to the free end of the swivel arm (28); and an actuator drive (42) for swiveling the swivel arm (38) relative to the supporting structure (18); characterized in that the swivel axis (40) of the swivel arm (38) is located at a distance from the swivel axis (22) of the cantilever arm (20), so that the swivel arm (38) is mounted eccentrically to the cantilever arm (20). 2. Device as claimed in claim 1, wherein the swivel arm (38) has an operational position, wherein, in the operational position of the cantilever arm (20), the second rotational joint (36) of the linear drive (28), is located in the immediate proximity of a plane (48"), which contains the swivel axis (40) of the swivel arm (38) and the centre of the first rotational joint (32) of the linear drive (28). 3. Device as claimed in claim 1, wherein the swivel arm (38) has an operational position, wherein, in the operational position of the cantilever arm (20), the second rotational joint (36) of the linear drive (28) is located on the other side of a plane (48"), which contains the swivel axis (40) of the swivel arm (38) and the centre of the first rotational joint (32) of the linear drive (28). 4. Device as claimed in claim 3, wherein the swivel arm (38) is mechanically locked in its operational position. 5. Device as claimed in claim 4, wherein the swivel arm (38) is, in its operational position, in contact with an abutment of the supporting structure. 6. Device as claimed in claim 4, wherein the actuator drive (42) has a limit stop, which determines the operational position of the swivel arm (38). 7. Device as claimed in any one of the claims 1 to 6, wherein when the swivel arm (38) is swiveled into its operational position, the distance between the swivel axis (22) of the cantilever arm (20) and a straight line connecting the two rotational joints (32, 36) of the linear drive (28) increases. 8. Device as claimed in any one of the claims 1 to 7, wherein the actuator drive (42) of the swivel arm (38) is a second linear drive, which is connected in a jointed manner on one side to a fixed point of the supporting structure (18), and, on the other side, to the swivel arm (38), wherein this second linear drive (42) is considerably weaker than the first linear drive (28). 9. Device as claimed in any one of the claims 1 to 7, wherein the actuator drive (42) of the swivel arm (38) is a rotational drive. 10. Device as claimed in any one of the claims 1 to 9, wherein the swivel arm (38) has a home position, in which the second rotational joint (36) of the linear drive (28) is arranged in such a way that in the home position of the cantilever arm (20) the first linear drive (28) is located essentially parallel to the cantilever arm (20). 11. Device as claimed in any one of the claims 1 to 10, wherein the first linear drive (28) is arranged laterally along the cantilever arm (20), wherein the first rotational joint (32) of the first linear drive (28) is secured laterally at free end of the cantilever arm (20). 12. Device as claimed in any one of the claims 1 to 11, wherein the first linear drive (28) is a hydraulic cylinder. 13. A tap hole plugging machine, comprising a swivel device (12) as claimed in any one of the claims 1 to 12, wherein said operational element is a tap hole plugging gun (16). 14. Device for swiveling an operational element substantially as hereinbefore described with reference to the accompanying drawings.

Documents:

1287-del-1998-abstract.pdf

1287-del-1998-claims.pdf

1287-del-1998-correspondence-others.pdf

1287-del-1998-correspondence-po.pdf

1287-del-1998-description (complete).pdf

1287-del-1998-drawings.pdf

1287-del-1998-form-1.pdf

1287-del-1998-form-13.pdf

1287-del-1998-form-19.pdf

1287-del-1998-form-2.pdf

1287-del-1998-form-3.pdf

1287-del-1998-form-4.pdf

1287-del-1998-form-6.pdf

1287-del-1998-gpa.pdf

1287-del-1998-petition-137.pdf

1287-del-1998-petition-138.pdf

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