AU642734B2 - Cable tendon drive system and method - Google Patents

Description

1 AUSTRALIA, L- 9 i: t P/OC/011 Form PATENTS ACT 1952 COMPLETE SPECIFICATION

(ORIGINAL)

FOR OFFICE USE Short Title: Int. Cl: Application Number: Lodged: Complete Specification-Lodged: Accepted: Lapsed: Published: Priority: Related Art:

I

TO BE COMPLETED BY APPLICANT OSTALINE PTY LIMITED Name of Applicant: Address of Applicant: 4/5 Lyn Parade, HOXTON PARK NSW 2171 Actual Inventor: Address for Service: ELROY PROSPER CASPERZ RONALD JOHN McKENZIE PETER MAXWELL ASSOCIATES Blaxland House Ross Street NORTH PARRAMATTA NSW 2151 Complete Specification for the invention entitled: CABLE TENDON DRIVE SYSTEM AND METHOD The following statement is a full description of this invention, including the best method of performing it known to me:- SNote: The description is to be typed in double spacing, pica type face, in an area not exceeding 250 mm in depth and 160 mm in width, on tough white paper of good quality and it is to be inserted inside this form.

14599/78- L Pnnted by C. J. THOMPSON, Commonwealth Government Printer, Canberra -2- The present invention relates to a cable tendon drive system and method and, more particularly, to such a system and method suitable to feed one or more cable tendons into a predrilled hole in a mine roof or the like.

Mine roofs and walls usually require reinforcement to prevent or minimise the likelihood of collapse. One form of reinforcement involves drilling a hole some 40 to 80 mm in diameter and up to 20 metres in length into the region requiring reinforcement. One or more cable "tendons" (steel cable designed for taking tensile loads in reinforcement situations) are fed into the hole so as to lie along the full length of the hole. Concrete is then pumped into the hole.

A bond is thus formed between the adjacent region and the cable tendons for t'Le purpose of reinforcing the region.

To date no satisfac-.ory mechanical cable tendon feed system has been available to feed the cable tendons into the o predrilled aperture. Accordingly the job is most usually carried out by manual labour. Manhandling of cable tendons (which have a typical bending radius of some 1.5 metres) is a labour intensive and dangerous task.

It is an object of the present invention to provide an automated cable tendon drive system and method which ovurcomes one or more of the abovementioned disadvantages.

Throughout the specification reference to a universal 25 arm is reference to a mounting arrangement which has the capability of moving the point of feed of the cable tendon drive system anywhere in a plane generally perpendicular to the bore into which the cable is to be fed together with the -3capability to tilt the angle of cable feed to the bore about at least one axis lying in the plane.

Accordingly, in one broad form of the invention, there is provided a cable tendon drive system comprising spaced apart rollers mounted on a universal arm; said rollers adapted to grip at least one cable and thrust said cable in a continuous and uninterrupted manner into a predrilled hole.

Preferably, said predrilled hole is located in a mine roof or mine wall.

In a further broad form of the invention, there is provided a method of feeding a cable tendon into a predriilled hole; said method comprising applying a continuous thrust to a cable tendon by spaced apart rollers mounted on a universal arm located a fixed distance from the entry to said predrilled hole, whereby said tendon is fed continuously and in an uninterrupted manner into said predrilled hole.

In a particular preferred form of the method of the invention, said rollers apply thrust to a plurality of cable tendons at the same time, whereby the plurality of cable tendons are fed together and continuously in an uninterrupted manner into the predrilled hole.

Preferably, the continuous feed is arrested when thrust force sensing means senses that the leading end or ends of said cable tendon or plurality of cable tendons has or have encountered a barrier to forward progress in said hole.

Preferably, the thrust force sensing means is provided implicitly in the stalling of the rollers.

-LI

Preferably, said rollers comprise opposed rollers having a bite therebetween which grips said cable tendons; at least one of said rollers driven by an air motor.

-4- Preferably, the relative values of the stall torque of said air motor and the friction of said bite upon said cable tendons is such that the air motor will stall before the cable tendons slip in said bite in the event of said cable tendons encountering an obstacle whilst being fed.

Preferably, a finite gap is maintained between said rollers in order to facilitate cable tendon feed into the bite between said rollers.

:0 In order that the invention may be more readily understood and put into practical effect, reference will now be made to accompanying drawings in which:- Fig. 1 is a side view of the cable tendon feed apparatus according to a first embodiment of the invention, and, Fig. 2 is a top plan view of the opposed roller portion of the cable tendon feed apparatus shown in Fig. 1.

Fig. 3 shows a third embodiment of the invention.

The cable tendon drive system 1 illustrated in Figs. 1 2 is adapted to pivot upon a vertical, fixed post or stub 2. The post or stub 2 is fixed to a working platform or other stable point of reference adjacent the predrilled aperture into which cable tendons 9, 10 are to be inserted.

The cable tendon drive system 1 comprises a first pivot cylinder 3 rotatably mounted upon the stub 2. A first horizontal extension arm 4 extends from the top of the pivot cylinder 3 and is supported by brace 24. The first horizontal extension arm 4 can rotate in the horizontal plane about fixed post 2. Rotation can be arrested by inserting lock pin 25 in one or other of the lock pin receiving holes 28 in the casing of the first pivot cylinder 3. The pin extends through the hole 28 and into a receiving aperture in fixed post or stub 2 thereby locking first horizontal extension arm 4 against pivotal movement about the post ur stub 2.

A second horizontal extension arm 6 is pivotally mounted at one end by means of stub 7 within second pivot cylinder 5. Second pivot cylinder 5 is fixed to the end of "o °0 first horizontal extension arm 4 opposite first pivot 00 °0 cylinder 3. Once again locking pin 26 can be inserted in one 0 or other of holes 28 and on into corresponding receiving °0 apertures (not illustrated) within stub 7 whereby second extension arm 6 can be arrested from rotation about and within second pivot cylinder A third pivot cylinder 8 is rotatably mounted about the 0C 0030 end of second extension arm 6 opposite second pivot cylinder Third pivot cylinder 8 supports a frame comprising roller oo housing 23. Third pivot cylinder 8 allows rotation of lie roller housing 23 about a vertical axis defined by second extension arm 6.

o° o The arrangement prescribed in relation to Fig. 1 allows the roller housing 23 to be placed at any point in a horizontal plane within reach of the arms 4, 6 and further allows the housing 23 to be tilted with reference to that horizontal plane. Locking pin 27 can be inserted in receiving holes 28 and thence into receiving apertures (not shown) within the second extension arm 6 for the purpose of -6locking the roller housing 23 against tilt about the hori.:ontal plane.

The roller housing 23 comprises a generally rectangular frame which houses and suipports within it an air motor 11, a driven roller 12 and an idler roller 13 as generally illustrated in Fig. 2. Upward shaft 21 of air motor 11 is connected by means of chain 22 to driven roller 12 which rotates upon driven roller shaft Idler roller 13 rotates upon idle:' roller shaft 19.

The idler roller 13 is mechanically urged in the direction of driven roller 12 by means of compression spring 14. The mechanical interconnection between the compression spring 14 and the idler roller shaft 19 comprises an idler tension shaft 15 having a tension nut mounted upon the shaft 15 and translatable there along by a screw thread on the surface of the shaft 15. Compression spring 14 pushes against one side of tension nut 16 and also against one part of the roller housing 23 as shown in Fig. 2. The degree of push imparted to the nut 16 (and hence to idler roller 13 by means of idler tension shaft 15 and idler roller shaft 19) is adjusted by translation of the tension nut 16 either towards or away from the spring 14.

The shaftc 19, 20 of idler roller 13 and driven roller 12 are generally parallel and spaced apart so as to define a bite region 29 between the rollers 12, 13. The width of "he bite 29 is determined by translation of stop nut 17 along idler tension shaft 15. Lock nut 18 is utilised to lock stop -7nut 17 into position.

Ideally, the width of the bite 29 is adjusted so that on the one hand there is a finite opening defined between the rollers 12, 13 (thereby facilitating the feeding of cable tendon ends into the bite region between the rollers 12, 13) and on the other hand the width of the bite region 29 is sufficiently small so that a good grip is maintained by the rollers 12, 13 on cable tendons 9, 10 such that air motor 11 will stall before slippage of rollers 12, 13 against tendons 10 9, 10 will take place in the event of tendons 9, encountering an obstruction during feed.

In a particular form of tpie first embodiment of the invention, grooves are indented into the faces of rollers 12, 13 and aligned so as to facilitate reception and grip of tendons 9, In this embodiment, the driven roller 12 has a diameter of approximately 75 mm (including a friction covering ooo material of approximately 7 mm). The idler roller 13 is of approximately the same diameter.

The cable tendon diameter is approximately 15 mm and feeds into a predrilled hole 30 in a mine roof or the like of approximately 45 to 70 mm diameter.

In use, the cable tendon drive system 1 is placed upon a fixed post 2; in this case being one of a plurality of such posts mounted on a working platform. With locking pins 26 27 disengaged the roller housing 23 is moved and tilted upon the arm assembly until the bite 29 of rollers 12, 13 is facing directly into predrilled hole 30. The plane of -8movement of the roller housing 23 is a maximum 1 metre from the entry to the predrilled hole Once in position, air motor 11 is actuated and one or more cable tendons 9, 10 are fed into the bite 29.

Frictional engagement of the tendons 9, 10 between the surfaces of the rollers 12, 13 causes driven roller 12 to urge the tendons 9, 10 into the predrilled hole 30 in a single, continuous, uninterrupted manner. When the tendons 9, 10 encounter an obstruction such as the far end of the °o °10 predrilled hole 30 then air motor 11 stalls. The cable o tendon drive system 1 can now be removed from the site of the 0 J on entry to the predrilled hole 30 and the additional operations o00 o involved with concreting the predrilled hole 30 can be carried out as usual in the manner already known in the art.

Fig. 3 shows a modified form of the invention wherein 000 oo two air motors 11A and 11B are utilised. In this embodiment each air motor is adapted to drive only one of the two oo 0 rollers 12, 13.

In additic., a disengaging mechanism 60 is incorporated whereby rollers 12, 13 can be moved apart a sufficient I distance to disengage the tendon located therebetween.

r The disengagement mechanism 60 comprises arms -2 attached at one end to collar 63 and at their opposiL_ erids to locknut assembly 17, 18. Rotation of handle 64 causes arms 61, 62 to be drawn away from the roller housing 23 whereby tension shaft 15 is caused to move away from roller 12 whereby rollers 13 and 12 are moved apart.

In addition the embodiment of Fig. incorporates a cross arm 65 whereby shaft 6 can be rotated upwardly or downwardly about shaft 65 by means of collar 66.

Arm 67 attached to collar 66 is driven by extensible member 68 whereby collar 66 is caused to rotate about cross arm shaft 65 thereby causing the roller housing 23 to be urged either upwardly or downwardly.

Extensible member 68 comprises a screwed collar inside which rotates threaded shaft 69. The threads of shaft 69 engage with the collar whereby the collar moves either towards or away from the roller housing 23 as the screwed shaft 69 is rotated. The shaft 69 can be rotated by means of handle In addition the grooves in the rollers 12, 13 can be varied in width to accommodate the larger diameter of other tubular materials to be inserted into blast holes and the like in mine roofs. In particular injected tube can be 0o.o inserted into holes in a mine roof using the assembly illustrated in Fig. 3.

The above describes some embodiments of the invention and modifications obvious to those skilled il the art can be made thereto without departing from the scope and spirit of *he present invention.

Claims (11)

1. A cable tenidon drive system comprising spaced apart rollers mounted on a universal arm (as defined in the specification); said rollers adapted to grip at least one cable and thrust said cable in a continuous and uninterrupted manner into a predrilled hole.

2. The system of claim 1 wherein said predrilled hole is located in a mine roof or mine i'all.

3. A method of feeding a cable tendon into a predrilled hole; said method comprising applying a continuous thrust to a cable tendon by spaced apart rollers mounted on a universal arm (as defined in the specification) located a fixed distance from the entry to said predrilled hole, whereby said tendon is fed continuously and in an uninterrupted manner into said predrilled hole.

4. The method of claim 3 wherein said rollers apply thrust to a plurality of cable tendons at the same time, whereby the plurality of cable tendons are fed together and continuously in an uninterrupted manner into the predrilled hole.

The method of claim 3 or claim 4 wherein feed is arrested when thru:'t force sensing means senses that the leading end or ends of said cable tendon or plurality of cable tendons has or have encountered a barrier to forward progress in said hole.

6. The method of claim 5 wherein the thrust force sensing means is provided implicitly in the stalling of said rollers.

7. The method of any one of claims 3, 4, 5 or 6 wherein said rollers comprise opposed rollers having a bite -11- therebetween which grips said cable tendons; at least one of said rollers driven by an air motor.

8. The method of claim 7 wherein the relative values of the stall torque of said air motor and the friction of said bite upon said cable tendons is such that the air motor will stall before the cable tendons slip in said bite in the event of said cable tendons encountering an obstacle whilst being fed.

9. The method of claim 8 wherein a finite gap is maintained between said rollers in order to facilitate cabe tendon feed into the bite between said rollers.

A cable tendon drive system as hereinbefore described vwih reference to the accompanying drawings.

11. A method of feeding a cable tendon into a predrilled hole as hereinbefore described with reference to the accompanying drawings. Dated this 11th day of August, 1993. OSTALTNE PTY LIMITED by their Patent Attorneys, PETER MAXWELL ASSOCIATES.