CA2460497C

CA2460497C - Rebar insertion device

Info

Publication number: CA2460497C
Application number: CA 2460497
Authority: CA
Inventors: John Fifield
Original assignee: Dywidag Systems International Canada Ltd
Current assignee: Dywidag Systems International Canada Ltd
Priority date: 2003-04-29
Filing date: 2004-03-09
Publication date: 2012-07-10
Anticipated expiration: 2024-03-09
Also published as: CA2460497A1; CA2427006A1

Abstract

An apparatus and method for inserting rebar bolts during mining ground or roof support operations is disclosed. The apparatus is removeably secured to the front head of an extendable stoper drill. The apparatus has a clutch assembly, comprising a roller, slide plate and an opposing backing plate. The axis of the roller is free to move along the slide plate at an oblique angle away from the pinch arm in the direction of extension. Extension of the drill causes the roller to apply pressure on a rebar bolt held between the slide plate and the backing plate locking it in place until the drill is retracted. When the drill is retracted, the roller moves away from the backing plate, releasing the pressure, and permitting the apparatus to slide down relative to the rebar bolt to grip the rebar bolt at a lower point. When the drill leg is next extended, the rebar bolt can be further driven into the hole penetrating the column of resin. The rebar bolt may be inserted using only the apparatus and the drill. The drill can be used in a normal fashion to drill holes, to spin the rebar bolt and to tension the rebar bolt with the apparatus mounted thereon.

Description

REBAR INSERTION DEVICE

CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims priority from Canadian Patent Application No. 2,427,006 filed April 29, 2003 having the same title and naming the same inventors.
MICROFICHE APPENDIX

[0002] Not applicable.
TECHNICAL FIELD

[0003] The present invention relates generally to mining ground or roof support, and particularly to an apparatus and method for inserting rebar bolts during mining ground or roof support operations.

BACKGROUND OF THE INVENTION

[0004] When mining underground, the rock strata are usually of such a type that it is necessary to stabilize the roof and/or walls of a tunnel by holding the strata in one mass. The conventional means for doing this is by fully or partially encapsulated resin bolting, involving drilling a hole, usually vertically, through the various strata, inserting a rod or rebar bolt into the hole and bonding the rebar bolt in place in the rock using resin grout. Once the hole has been drilled to the proper diameter and depth in relation to the diameter and length of the rebar bolt to be used, resin is introduced, typically as a package having two sealed components, to the toe of the drill hole. The amount of resin that is inserted will determine the amount of encapsulate. The resin package is pierced by the insertion of the rebar DOCSOTT: 199524\1 bolt, permitting the resin components to mix and be activated. The hole diameter is such as to permit the downward flow of resin about the bolt in order to bond it to the rock strata. Once the resin cartridge is fully pierced, a socket attachment on the drill is used to spin the rebar bolt and fully insert it into the drilled hole and tensioned. The several rock strata are thus clamped together to form a composite beam with a strength considerably greater than the sum of the individual strata acting separately. This eliminates the need for timbering or other known bolting mechanisms. Such a system is widely used and offers performance superior to that of traditional timbering. When fully encapsulated, the rebar bolt offers ground support along its entire length. Because the rebar bolt is fully encapsulated, it is protected by the resin grout from the potential effects of corrosion.

[0005] A number of devices have been devised to facilitate the insertion of the rebar bolt through the resin cartridge. Because the mining environment is extremely dusty and generally unforgiving, such devices are preferably both extremely simple and robust in construction. For example, certain devices exist that incorporate the extendable nature of the drill used to drill the hole, making use of the drill's capacity to extend vertically upward to force the rebar bolt into the hole. They include slotted plates attached to a chain and ring and sections of oversized angled pipe that can be loosely draped around the rebar bolt, to grip the rebar bolt and push it upward, as shown in Figure 1.
With respect to the angled pipe device, the angled cut points upward when positioned on the drill.

[0006] Generally, the rebar bolt cannot entirely pierce the resin cartridge with a single extension of the drill.
Rather, the drill must be used in iterative fashion.
Therefore, such devices typically accept the rebar bolt in releasable fashion. The known mechanisms used to grip the rebar bolt are crude and do not provide a positive grip on the rebar as it is forced upward through the column of resin. The angled pipe device for example relies on the binding action of the rock bolt plate on the rebar as the stoper leg is extended. When the leg pressure is released the rock bolt plate loosens its contact with the rebar and ceases to engage the rebar bolt. The plate falls freely along the rebar as the stoper leg is retracted. When the leg is again extended then the plate must again bind itself against the rebar bolt for the next upward extension of the stoper leg.
Slippage of the roof bolt plate along the rebar is common. The frictional contact relies on the binding action between the plate and the rebar. The plate hole diameter and the angle cut on the pipe attachment are variable and will affect performance of this device. The chain and ring type makes it very difficult to direct the leg pressure perpendicular to the rebar and slippage and loss of stoper control can occur. In either case, the rebar bolt remains relatively fixed in place by the resin fixing agent surrounding it and filling the space between the drilled hole and the rebar.

[0007] Such devices suffer a disadvantage in that they do not tightly grip the rebar bolt. Thus, partial manual insertion of the rebar bolt into the hole to a depth of a foot or so is required before these devices can be used to complete the insertion process through the entire resin cartridge. This requires tremendous force and applies enormous strain on the worker's, body. The repetitive strain may have detrimental long term health effects that have yet to be fully studied.

[0008] This deficiency introduces considerable inconvenience into the rebar bolting process. Once drilling has been completed, the drill. operator must set the drill aside to free both hands and manually insert the rebar bolt into the hole. Once sufficient manual insertion has been achieved, the operator must position the drill under both the hole and the rebar bolt, slide the device over or around the rebar bolt and then drape the rebar insertion device onto the drill. The draping process is somewhat delicate, because sufficient friction must be applied to keep the device from disengaging from the rebar bolt, but without dislodging the rebar bolt from the hole.

[0009] The device must thereafter be carefully manipulated by the operator to ensure both frictional engagement of the rebar bolt during extension of the drill to permit insertion of the bolt and free downward travel of the device relative to it during retraction of the drill so as to permit repositioning of the device.

[0010] Once the rebar bolt penetrates the resin cartridge it is spun in order to mix the resin components before hardening. Typically, the rebar bolt is firmly gripped by its nut or forged end using a dolly or socket attachment inserted into the chuck of the drill. The dolly imparts rotation to the bolt that is combined with further extension of the drill to fully insert the rebar bolt and ensure that it is fully encapsulated in the resin. Once the resin has cured sufficiently, the drill and dolly are again applied to the nut in order to tighten the bolt to the required torque. Thus, the insertion device must be disengaged from the rebar bolt in order to permit the dolly to engage the rebar bolt and spin and torque the bolt.

[0011] All of the foregoing is exacerbated by the fact that the known reba.r insertion devices typically have an annular structure, such as a ring, that will loosely fit over the head of the stoper drill. The loose fit also means that the device is normally removed from the drill during normal drilling operations and also the loose fit can be the cause of slippage and misalignment and loss of control of the stoper drill when pushing the rebar through the column of resin. The practice is to remove the device from the stoper drill at each hole and then placing the device again over the top head of the drill with each bolt installed. This requires that the insertion device be continually handled to remove and reposition it at every hole.

[0012] When the device is removed from the drill following insertion of the rebar it has to be laid down.
It may end up at the operator s feet or it may be out of reach of the drill operator when needed on the next bolt installation. This presents an inconvenience resulting in delay, which is counterproductive and also poses a tripping hazard that is a safety concern.

[0013] The use of such devices is thus time consuming and cumbersome for the operator. These factors tend to result in injuries during use, including pinched fingers, struck legs and shins. Nevertheless, the force required to insert the rebar bolt through the resin cartridge to a sufficient degree to permit the drill and dolly to engage the nut of the bolt and complete the insertion is such that complete manual insertion is unlikely, if not impossible. Accordingly, there remains a need for an improved rebar insertion device.

SUNMARY OF THE INVENTION

[0014] It is therefore an object of the present invention to provide an improved rebar insertion device that may be releasably mounted on a stoper drill.

[0015] It is a further object of the present invention to provide an improved rebar insertion device that may be used at all stages of the insertion process including the initial insertion step.

[0016] It is still another object of the present invention to provide an improved method of inserting rebar that increases the speed of the resin bolting process.

[0017] In accordance with an embodiment of the present invention, there is provided an improved rebar insertion device that may be releasably mounted on the front head of the stoper drill. The size and light weight of the device is such that the normal operation or performance of the drill is not adversely impacted. Nevertheless, the device remains simple and extremely robust in both construction and operation. The improved device maintains full control of the rebar with no unexpected slippage by a positive grip, but does not introduce any points of weakness on the rebar. It encourages the use of the device from the point of insertion until the bolting operation is complete, thus avoiding the need for an initial manual insertion of the rebar or to remove the device during the bolting process.

[0018] According to a first broad aspect of the invention, there is disclosed a device for inserting a reinforcing bolt into a hole in a wall, the device comprising a clamp for removeably securing the device to a reciprocal driver mechanism; a clutch assembly affixed to the clamp, the clutch assembly comprising a pair of slide plates disposed opposite one another; and rollers disposed in rolling engagement with each slide plate and facing one another, the rollers each having a surface for frictionally engaging the bolt, wherein the rollers and the slide plates cooperate to lock the bolt against movement relative to the device in a first direction and release the bolt to permit movement relative to the device in an opposite direction.

[0019] According to a further aspect of the invention, there is disclosed a system for inserting a reinforcing bolt into a hole in a wall, the system 'comprising an extendable drill mechanism used to create the hole; a device comprising a clamp for reversibly securing the device to a reciprocal driver mechanism; and a clutch assembly affixed to the clamp, the clutch assembly comprising a backing plate for frictionally engaging the bolt; a slide plate disposed opposite the backing plate;
and a roller disposed in rolling engagement with the slide plate and facing the backing plate, the roller having a surface for frictionally engaging the bolt, wherein the roller cooperates with the slide plate and the backing plate to lock the bolt against movement relative to the device in a first direction and release the bolt to permit movement relative to the device in an opposite direction.

[0020] According to a further aspect of the invention, there is disclosed a method of inserting a reinforcing bolt into a hole in a wall, the method comprising mounting, onto an reciprocal driver mechanism, a rod insertion device, comprising a clamp for rigidly removeably securing the device to the mechanism; and clutch assembly affixed to the clamp, the clutch assembly comprising a backing plate for frictionally engaging the bolt; a slide plate disposed opposite the backing plate;
and a roller disposed in rolling engagement with the slide plate and facing the backing plate, the roller having a surface for frictionally engaging the bolt;
inserting a bolt into the clutch assembly; extending the mechanism to drive the bolt toward and. into the hole; as required, successively retracting the mechanism to permit the device to move toward a second point further away from the opening on the rod without dislodging it; and extending the mechanism to drive the bolt further into the hole; and retracting the mechanism to permit the clutch assembly to be disengaged from the bolt [0021] According to a further aspect of the invention, there is disclosed a method of resin bolting a rock structure in a mine, comprising mounting, onto an extendable drill mechanism, a rebar insertion device, comprising a clamp for removeably securing the device to the mechanism; and a clutch assembly affixed to the clamp, the clutch assembly comprising a backing plate for frictionally engaging a rebar bolt; a slide plate disposed opposite the backing plate; and a roller disposed in rolling engagement with the slide plate and 9 _ facing the backing plate, the roller having a surface for frictionally engaging the rebar bolt, drilling a hole in the rock structure using the drill; inserting a resin cartridge or cartridges into the hole; inserting a rebar bolt into the clutch assembly; extending the mechanism to drive the rebar bolt toward and into the opening; as required, successively retracting the mechanism to permit the device to move toward a second point further away from the hole on the rebar bolt without dislodging it;
and extending the mechanism to drive the rebar bolt further into the hole; whereby the rebar bolt pierces the column of resin cartridges and causes its contents to be intermingled.

BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Further features and advantages of the present invention will become apparent from the following detailed description, taken in combination with the appended drawings, in which:

[0023] Figure 1 is a view of certain prior art rebar insertion devices.

[0024] Figure 2 is a side view of an embodiment of the present invention mounted and in position;

[0025] Figure 3 is a plan view of the embodiment of Figure 2; and [0026] Figure 4 is a side view of the embodiment of Figure 2.

[0027], It will be noted that throughout the appended drawings, like features are identified by like reference numerals.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0028] Referring now to Figure 2, the described embodiment of the present invention comprises a rebar insertion device 100 that can be removeably mounted onto the head 111 of an extendable hand held drilling machine 110 to insert a rebar bolt 120 into a hole 130 drilled into a wall structure 131 of the mine shaft. For the purposes of this discussion, the term "wall" will be understood to include any wall structure to be supported by bolting including a roof, and the term "rebar bolt"
will be understood to include any kind of rod suitable for insertion into an opening in the wall for reinforcement or stability purposes. The device 100 positively and firmly grips the rebar bolt 120 such that it extends substantially coaxially with the axis of the drilled hole 130. A two-component resin cartridge 140 is shown inserted partially into the hole 130.

[0029] A suitable drilling machine 110 is a conventional stoper drill, well-known in the art. Suitable stoper drills 110 include the JOY, SECAN, CANUN and GARDENER
DENVER models and will not be further described herein.

[0030] Similarly, the rebar bolt 120 is a conventional rock bolt of the type commonly used in mining and will not be further described herein.

[0031] The rebar insertion device 100 is shown in plan view in Figure 3. The device 100 comprises a drill head attachment 200 and a roller clutch mechanism 210.

[0032] The drill head attachment 200 permits the insertion device 100 to be rigidly mounted to the drill head 111 of the stoper drill 110. It comprises a nearly circular clamp jaw 201, of preferably steel or iron construction, a bolt 205, a lock washer 206 and a lock nut 207. The exact contour of the clamp jaw 201 corresponds to the outside contour of the stoper drill 110 at the mounting point. The clamp jaw 201 is welded near its middle to the roller clutch mechanism 210. Each end of the clamp jaw 201 terminates in an opening 202 through which the bolt 205 may pass and be fixed by the lock washer 206 and the nut 207. The bolt 205, lock washer 206 and nut 207 cooperate to fix the clamp jaw 201 (and thus the insertion device 100) tightly and rigidly about the cylindrical drill head 111 of the stoper drill 110.

[0033] As shown in Figure 4, the height of the clamp jaw 201 is sufficient to prevent the insertion device 100 from twisting relative to the drill head 110. In the described embodiment, for mounting on a conventional stoper drill 110, the clamp jaw 201 is defined by a pair of parallel semi-circular arms 203 each of which is welded near its middle to the roller clutch mechanism 210 and at the other end to a vertical bar 204 through which the opening 202 passes. The bar 204 and clamp jaw 201 thickness is sufficient to withstand any torsional and tension stresses applied to the device 100 while in operation.

[0034] The roller clutch mechanism 210 comprises a roller assembly 211 and an L-shaped fixed arm 240.

[0035] The roller assembly 211 comprises an enclosure 212, a slide plate 220 and a roller 230. The enclosure 212 is enclosed except for a single end, with the open (front) end 213 facing away from the drill head attachment 200.

[0036] The clamp jaw 201 of the drill head attachment 200 is welded onto the back end 214 of the enclosure 212.
As shown in Figure 4, the height of the enclosure 212 is sufficient to accommodate the desired extent of travel of the roller 230, as discussed below. Additionally, the height permits an operator relatively easy access to the interior of the enclosure 212, in order to clear out any debris that may have accumulated in it and that may inhibit the operation of the device 100.

[0037] The sides 215, back 214 and ceiling 217 of the enclosure 212 are preferably formed of steel or iron plate material. The floor 218 of the enclosure 212 is composed of much thicker plate material that provides increased stability and strength to the device 100. The floor 218 extends beyond the side walls 215 and its top edges 219 are slightly beveled in these regions, in order to protect the device 100 from any falling debris.

[0038] The two side surfaces 215 of the enclosure 212 each have a slot 216 extending across it along an oblique angle upwards and away from the front: edge of the side 215.

[0039] The slide plate 220, also preferably formed of steel or iron plate, extends in a plane extending between the sides 215 and lying parallel to and below the plane defined by the pair of slots 216, by a separation defined by the radius of the roller 230.

[0040] The roller 230 comprises a cylindrical wheel 231 having a removeable retainer pin 232 passing therethrough. The outer surface of the wheel 231 is machined to provide a strongly knurled texture by a plurality of grooves and/or protrusions 233, so as to increase the friction between it and any surface that it engages, including both the slide plate 220 and the rebar bolt 120, even in the presence of dust, rock fragments or other particulate debris. The wheel 231 is machined out of solid cylindrical steel or iron stock. It is heat treated to harden it for durability and extended wear life. This makes it harder than the rebar bolt 120 so that the knurling has the ability to firmly grip the rebar bolt 120. The wheel substantially occupies the distance between the interior surfaces of the sides 215, with minimal clearance, in order to permit easy movement of the wheel 231 relative to the enclosure 212, without significant lateral play that would permit the retainer pin 232 to escape the travel path defined by the slots 216, and in order to inhibit the introduction of debris.
The diameter of the wheel 231 is sufficiently large to limit the ability of a rebar bolt to tilt, wiggle or otherwise move, when pinched between the wheel 231 and the L-shaped fixed arm 240 as discussed below. A wheel 231 diameter of about 11-,4" has been found to be suitable.

[0041] The retainer pin 232 is also of solid cylindrical iron or steel, or may be a rolled steel pin or split pin having a diameter that corresponds to the width of the slots 216 in a sliding fit. The length of the retainer pin 232 is sufficient to extend substantially through each slot, preferably without extending beyond the outer surface of the enclosure 212.
The retainer pin 232 may be driven entirely through the wheel 231 releasing the wheel 231 from the slots 216 for removal and replacement of the wheel 231. The roller 230 is housed within the enclosure 212 so that the retainer pin 232 engages corresponding slots 216. Thus, the knurled wheel 231 is free to slide along the path defined by the slots 216.

[0042] The slide plate 220 provides support for the roller 230 at any given position along the path defined by the slots 216, thus reducing the strain that must be borne by the retainer pin 232. Additionally, the knurled texture of the wheel 231 may generate additional friction from its contact with the slide plate 220, thus increasing the grip that may be applied to the rebar bolt 120 as discussed below.

[0043] The fixed arm 240 comprises two components, an extension arm 241 and a backing plate 242, in an L-shaped orientation. The extension arm 241 extends co-linearly with one side 215 of the enclosure 212 beyond the front 213 of the enclosure to abut the backing plate 242. The extension arm 241 has a floor similar in dimension and co-planar with that of the enclosure 212, and bevelled on the outside surface only.

[0044] The extension arm 241 and the backing plate 242 define a rectangular space between the backing plate 242 and the front 213 of the enclosure 212. The height of the backing plate 242 is sufficient to cooperate with the knurled wheel 231, as discussed below, to ensure that a rebar bolt 120 may be firmly pinched against the backing plate 242 by the wheel 231 to inhibit tilting, wiggling or any other kind of movement. In this embodiment, a backing plate 242 height of 11" has been found to be suitable. As shown in Figures 2 to 4, the height of the backing plate 242 may be less than that of the enclosure 212. This permits relatively easy access by the operator to the enclosure 212 in order to clear out debris, or to the space between the backing plate 242 and the enclosure 212, in order to insert the rebar bolt 120 from above, and serves to reduce the overall weight of the device 100.

[0045] The backing plate 242 is composed of steel or iron plate material, and also has a :bevelled floor (on three sides) co-planar with that of the enclosure 212.
There is no bevelling on the surface facing the enclosure 212, just as there is no bevelling on the floor underneath the opening 213.

[0046] The length and orientation of the slots 216, together with the dimensions of the roller 230 and of the fixed arm 240 ensure that when the retainer pins 232 are near the front of the enclosure 212, the roller 230 extends sufficiently beyond the front opening 213 of the enclosure 212 and into the space between the enclosure 212 and the backing plate 242 to firmly pinch a rebar bolt 120 against the backing plate 242. In this position, the rebar bolt 120 is unable to move relative to the device 100, even if the drill 110 and the device 100 are rotated about the rebar bolt 120. The absence of a bevelled floor beneath the facing surfaces of the enclosure 212 and the backing plate 242 (and indeed the extension arm 241) ensure that a maximum surface area grips the rebar bolt 120 in this position.

[0047] When the retainer pin 232 is toward the back of the enclosure 212, the wheel 231 is sufficiently retracted into the enclosure 212, so that clearance is created between it and the rebar bolt 120 and the device 100 is free to move relative to the rebar bolt 120.

[0048] In operation, the insertion device 100 is bolted to the drill head 111 of the stoper drill 110, so that the slots 216 extend away and downwardly from the drill head 111, that is toward the tunnel floor. The bevelling 219 on the floor 218 of the enclosure 212, the extension arm 241 and the backing plate 242 serves as an intuitive visual clue to the operator as to the proper vertical orientation of the device 100.

[0049] A suitable hole 130 is then drilled using the stoper drill 110. Typically, in rebar bolting operations, the hole 130 extends substantially vertically into the roof strata of the mine shaft. As discussed previously, the diameter of the hole 130 is such as to ensure a relatively tight fit with the rebar bolt 120 to be inserted, yet allow the downward flow of resin grout about the rebar bolt 120 in order to bond it to the rock strata.

[0050] Once the hole 130 has been prepared, one or more two-component resin cartridges 140 are pushed up into the drilled hole 130, often associated with a loading stick.

[0051] The rebar bolt 120 to be inserted into the hole 130 is installed within the roller clutch mechanism 210.
In particular, the rebar bolt 120 is fed through the rectangular space defined by the fixed arm 240 and the enclosure 212, preferably in firm contact with the backing plate 242 and optionally the extension arm 241.

[0052] The rebar bolt 120 may be inserted beneath the device 100, with a. slight upward twist. The knurled wheel 231 will be naturally forced upward and toward the back 214 of the enclosure 212 during insertion so as to permit relatively easy insertion until the desired amount of rebar bolt 120 extends beyond the top of the device 100. Once the rebar bolt 120 has been sufficiently inserted through the device 100, gravity, or if required, a slight downward jerk on the rebar bolt 120 will cause the knurled wheel 231 to firmly engage it and provide a positive grip on the rebar bolt 120. The knurled wheel 231 thereafter causes a pinch point on the rebar bolt 120 at the point of contact between the rebar bolt and the wheel 231, providing a strong positive grip on the rebar bolt 120 with no slippage until loosened by releasing the stoper drill leg pressure.

[0053] So long as the stoper drill 110 is thereafter maintained relatively upright, the weight of the rebar bolt 120 itself will be sufficient to impose downward pressure on the knurled wheel 231 in order to maintain the firm grip on the rebar bolt 120.

[0054] With the rebar bolt 120 inserted into the device 100, the top of the rebar bolt 120 is lined up with the collar of the hole 130 and is allowed to approach and enter the hole opening 130, by extending the stoper drill 110, which is braced against the tunnel floor.

[0055] Once the rebar bolt 120 has been tucked inside the hole 130, the stoper drill 110 may be thereafter extended to its full height. As the stoper drill 110 is extended, the friction between the knurled surface 232 of the wheel 231 and the rebar bolt 120 firmly locks the rebar bolt 120 against sliding relative to the device 100.

[0056] Thus, the rebar bolt 120 is forced upward through the column of resin and further into the hole 130 with the extension of the stoper drill 110.

[0057] Once full (or a sufficient amount of) extension of the stoper drill 110 has been achieved, the drill 110 is allowed to retract. As it does so, the force applied by the upward pressure of the stoper drill 110 on the rebar bolt 120 is reduced or removed, allowing the wheel 231 to move slightly upward and toward the back 214 of the enclosure 212 thereby releasing the grip on the rebar. Nevertheless, the tendency of the wheel 231 is to remain in slight contact with the rebar bolt 120, which keeps the device 100 from completely disengaging from the rebar bolt 120. Rather the two remain in a sliding fit.
Thus, the device 100 is allowed to travel downward along the rebar bolt 120 (which remains firmly fixed in place by the tight fit between it and the hole 130) to a new point lower down along the rebar bolt 120.

[0058] When the stoper drill 110 has been fully or sufficiently retracted, it may be once again extended.
As before, the upward pressure created by extending the stoper drill 110 will cause the wheel 231 to impose a corresponding pinch pressure on the rebar bolt 120 at the new point of contact, which is below the original gripping point, so that the rebar bolt 120 may be forced further up into the hole 130 with continued extension.

[0059] As necessary, further iterations of the retraction and subsequent extension of the stoper drill 110 may be made until the resin cartridges 140 have been fully pierced by the rebar bolt 120.

[0060] The penetration of the rebar bolt 120 through the cartridge pouches 141, 142, allows their respective contents to combine. To ensure adequate mixing, the rebar bolt 120 is spun for a period of time. The spinning process also slightly accelerates the descent of the resin grout down the hole and about the deformations along the length of the rebar bolt 120.

[0061] At this point, the rebar bolt 120 is disengaged from the device 100, which remains tightly bolted to the head of the drill 110. A dolly is inserted into the chuck of the drill (replacing the drill bit) and used to spin and completely insert the rebar bolt 120 until it abuts the collar of the drill hole 130, in the manner hereinbefore described.

[0062] When sufficient spinning has been accomplished to adequately mix the two components of the resin, then the rebar bolt 120 is held firmly to the rock face and maintained motionless in place to allow the chemical reaction of the resin fixing agent to take effect, curing the resin and hardening it to firmly bond the rebar bolt 120 to the surrounding rock within the drilled hole 130.
This step is facilitated by the support provided by the stoper drill 110 and the dolly. Once a certain amount of time has elapsed, the stoper drill 110 and the dolly may be used to sufficiently tension the installed rebar bolt 120.

[0063] Thereafter, the dolly may be replaced by the drill bit and the stoper drill 110 may be repositioned in order to drill a subsequent hole, wherein the process can be repeated as required.

[0064] The insertion device 100 of the present invention is a small compact and efficient tool that mounts directly on the head 111 of the stoper drill 110 and stays there. The device 100 is so small and lightweight that it does not have any significant effect on the drilling, spinning or tensioning performance of the stoper drill 110. When it is time to insert a rebar bolt.
120, the device 100 is mounted and ready for use.

[0065] Because the insertion device 100 is rigidly attached to the drill 110, it eliminates the requirement to mount and dismount it from the stoper drill 110 with each rebar bolt 120 that is installed. This avoids the constant handling that is associated with other known types of rebar pushers, that adds steps to the rebar installation procedure and thereby reduces productivity.

[0066] Moreover, there is no requirement to set the stoper drill 110 aside and manually insert the rebar bolt 120 before positioning the stoper drill 110 again to continue the insertion of the rebar bolt 120 through the column of resin 140. Rather than having to partially insert the rebar bolt 120 manually, the rebar bolt 120 is simply positioned on the device 100, which thereafter holds the rebar bolt 120 firmly. The stoper drill 110 is extended and the initial and subsequent push and release steps to accomplish penetration can easily be achieved.

[0067] The insertion device 100 of the present invention improves productivity and improves safety by providing a very positive grip on the rebar bolt 120 with no unexpected slippage and by eliminating the need to handle the insertion device 100. It is positioned on the stoper drill 110 and secured there, to be removed only if there is a requirement to perform maintenance on the stoper drill 110. Thus the user has full control of the rebar bolt 120 to safely insert it.

[0068] Through testing, no permanent deformation of the rebar bolt 120 as a result of use with the insertion device 100 were identified. The insertion device 100 has demonstrated durability. it is simple and robust in construction, with only a single moving part. The device 100 provides for sufficient clearance to access components and its strength ensures that the device 100 will continue to function within the harsh mining environment. A prototype has been used to install on the order of 200 rebar bolts 120 with no apparent wear. The insertion device 100 has been successfully used with both 6' and 8' rebar bolts 120.

[0069) Anecdotal studies of use of the device 100 show that over an entire shift, use of the insertion device 100 may result in a productivity increase of over 10 rebar bolts 120 per shift, with less fatigue.

[0070) It will be apparent to those skilled in this art that various modifications and variations may be made to the embodiments disclosed herein, consistent with the present invention, without departing from the spirit and scope-of the present invention.

[0071] Other embodiments consistent with the present invention will become apparent from consideration of the specification and the practice of the invention disclosed therein.

Forexarr le; rear bolt 121,0maybe morefirmlygripped by kebiddq plan 2142, ifa groove or notch 242a adapt to amommodatea taartioa of the sarmkence of The rear tit 120 were introduced in the face of the bacbq plate 2 opposi the opening 21x.
Such a gm -e 2N2amaybe semi-circulat tria alar(a shosinFigu 5 add} or fee ngulariin profite.

[0073] Further, or in the alternative, the face of the backing plate 242 might additionally be knurled in order to provide increased friction and thus increased grip on the rod if required. Care must be taken, however, to ensure that the grip is not excessive, so as to prevent the ability of the device 100 to slide down along the length of the bolt 120, during retraction of the extendable stoper drill 110. For example, while it may be beneficial in some applications, to incorporate horizontal ridges along the face of the backing plate 242, which are adapted to engage the deformations on the rebar bolt 120, it is thought that while additional support is thereby provided to the rebar bolt 120, such ridges would significantly impede the ability of the device to move along the length of the rebar bolt 120 during the retraction step.

[0074] Similarly, the face of the slide plate 220 may also be knurled in order to increase the grip between it and the wheel 231.

[0075] The clamp jaw 201 need not be necessarily welded on the back end 214 of the enclosure. Alternatively, it may in fact be welded onto one of the side surfaces 215 of the enclosure 212. Indeed, the clamp jaw 201 may be of a cast construction with no welded connection to either the back end 214 or one of the side surfaces 215 of the enclosure, with a removable wheel 231 and retaining pin 232 assembly.

[0076] The structure may be made of cast iron or steel, or even aluminum or cast aluminum, with replaceable steel wear surfaces.

[00 Referring now to the embodiment 210b show in Figures 7 and S. those having ordinary skiff in thi s art will readily recognize that the backing plate 242M' Figures 5 and 6 might be replaced bya complementary roller assembly 233a, comprising a roller 235, slide plate 2#1 and eaclosute 21{ Because the complementaryrollerwould not provide a vertical surface against which the rod can be rested, there maybe addi player embble in the rebar bolt 120 in such a de-ice, although this could largelybe eliminated bysuitable extension of the ceiling 217 of the enclos sor other suppartmechanism. Aguide asseembly2l6a for limiting the angular movement of the bolt relative ID the device may also be included.

[0078[ hzeover, the device may optionally be adapted to be used with mechanized bolting machines. In such a case, the fed sfide action of the roller dutch mechanism 2lOb maybe used to GnÃx luugr ten? IS u[cabl1 bultuiti into a drill hulc.

[00791 Accordingly, the specification and the embodiments are to be considered exemplary only, with a true scope and spirit of the invention being disclosed by the appended claims.

Claims

1. A device for inserting a reinforcing bolt into a hole in a wall, the device comprising:
a clamp for removably securing the device to a reciprocal driver mechanism;
and a clutch assembly affixed to the clamp, the clutch assembly comprising:
a backing plate for fractionally engaging the bolt;

a slide plate disposed opposite the backing plate; and a roller disposed in rolling engagement with the slide plate and facing the backing plate, the roller having a surface for fractionally engaging the bolt;

wherein the roller cooperates with the slide plate and the backing plate to lock the bolt against movement relative to the device in a first direction and release the bolt to permit movement relative to the device in an opposite direction.

2. A device as claimed in claim 1, wherein the slide plate is disposed at an oblique angle with respect to the backing plate.

3. A device as claimed in claim 1, further comprising an enclosure about the slide plate and roller.

4. A device as claimed in claim 3, wherein the side walls of the enclosure support the movement of the roller along the slide plate.

5. A device as claimed in claim 4, wherein the side walls comprise slots that guide the movement of the roller along the slide plate.

6. A device as claimed in claim 2, wherein the device is mounted on the mechanism so that the plane of the slide plate moves away from the backing plate in the direction of extension.

7. A device as claimed in claim 1, wherein the roller has a surface that inhibits slippage in the presence of debris.

8. A device as claimed in claim 6, wherein the surface is knurled.

9. A device as claimed in claim 3, wherein the enclosure shields the roller and slide plate from debris.

10. A device as claimed in claim 3, wherein the enclosure permits access to clear out accumulated debris.

11. A device as claimed in claim 1, mounted on an extendable drill used to create the hole in the wall.

12. A device as claimed in claim 1, wherein the clamp is mounted on the drill head of the mechanism.

13. A device as claimed in claim 11, wherein the extendable drill may be used with the device mounted thereon.

14. A device as claimed in claim 1, wherein the backing plate comprises a notch support to restrict angular movement of the bolt.

15. A device as claimed in claim 1, wherein the surface of the backing plate is knurled.

16. A device as claimed in claim 1, wherein the surface of the slide plate is knurled.

17. A device as claimed in claim 1, wherein the device is composed of cast iron.

18. A device as claimed in claim 1, wherein the device is composed of steel.

19. A device as claimed in claim 1, wherein the device is composed of aluminum.

20. A device as claimed in claim 19, wherein the device has replaceable steel wear surfaces.

21. A device for inserting a reinforcing bolt into a hole in a wall, the device comprising:
a clamp for removably securing the device to a reciprocal driver mechanism;
and a clutch assembly affixed to the clamp, the clutch assembly comprising:
a pair of slide plates disposed opposite one another; and rollers disposed in rolling engagement with each slide plate and facing one another, the rollers each having a surface for frictionally engaging the bolt;
wherein the rollers and the slide plates cooperate to lock the bolt against movement relative to the device in a first direction and release the bolt to permit movement relative to the device in an opposite direction.

22. A device as claimed in claim 21, further comprising a guide assembly for limiting the angular movement of the bolt relative to the device.

23. A system for inserting a reinforcing bolt into a hole in a wall, the system comprising:
an extendable drill mechanism used to create the hole;

a device comprising:

a clamp for reversibly securing the device to a reciprocal driver mechanism;
and a clutch assembly affixed to the clamp, the clutch assembly comprising:

a backing plate for fractionally engaging the bolt;

a slide plate disposed opposite the backing plate; and a roller disposed in rolling engagement with the slide plate and facing the backing plate, the roller having a surface for frictionally engaging the bolt, wherein the roller cooperates with the slide plate and the backing plate to lock the bolt against movement relative to the device in a first direction and release the bolt to permit movement relative to the device in an opposite direction.

24. A method of inserting a reinforcing bolt into a hole in a wall, the method comprising:
mounting, onto an reciprocating driver mechanism, a rod insertion device, comprising:
a clamp for rigidly removeably securing the device to the mechanism; and a clutch assembly affixed to the clamp, the clutch assembly comprising:
a backing plate for frictionally engaging the bolt;

a slide plate disposed opposite the backing plate; and a roller disposed in rolling engagement with the slide plate and facing the backing plate, the roller having a surface for fractionally engaging the bolt;

inserting a bolt into the clutch assembly;

extending the mechanism to drive the bolt toward and into the hole;

as required, successively: retracting the mechanism to permit the device to move toward a second point further away from the opening on the rod without dislodging it;
and extending the mechanism to drive the bolt further into the hole; and retracting the mechanism to permit the clutch assembly to be disengaged from the bolt.

25. A method of resin bolting a rock structure in a mine, comprising:
mounting, onto an extendable drill mechanism, a rebar insertion device, comprising:

a clamp for removeably securing the device to the mechanism; and a clutch assembly affixed to the clamp, the clutch assembly comprising:
a backing plate for frictionally engaging a rebar bolt;

a slide plate disposed opposite the backing plate; and a roller disposed in rolling engagement with the slide plate and facing the backing plate, the roller having a surface for frictionally engaging the rebar bolt, drilling a hole in the rock structure using the drill;
inserting a resin cartridge into the hole;

inserting a rebar bolt into the clutch assembly;

extending the mechanism to drive the rebar bolt toward and into the opening;

as required, successively: retracting the mechanism to permit the device to move toward a second point further away from the hole on the rebar bolt without dislodging it; and extending the mechanism to drive the rebar bolt further into the hole;

whereby the rebar bolt pierces the resin cartridge and causes its contents to be intermingled.