GB2030492A - Bolt magazine for drilling and bolting apparatus - Google Patents

Abstract

A bolt magazine, for drilling and bolting apparatus used for supporting the "roof" of a mine gallery and comprising a turret 1 pivotally mounted on a support 4 and carrying a drilling carriage 9 and a bolting carriage 10, comprises a frame fixed to the support of the turret and has two endless chains 27 in parallel longitudinally spaced planes the chains being drivable synchronously. At least a part of the links of these chains has the shape of claws which, together with guides, ensure the holding and feed of the bolts. The magazine is particularly suitable for use with self-anchoring expansion bolts and resin- sealed bolts. <IMAGE>

Description

SPECIFICATION Bolt magazine for drilling and bolting apparatus The present invention relates to a bolt magazine for drilling and bolting apparatus, used for supporting the "roof" of, for example, a mine gallery.

The conventional technique of roof propping involves engaging, in each of the holes which have been drilled in the "roof", a bolt carrying at its end a fitting which by an expansion effect anchors itself at the end of this hole, after which the tightening of this bolt produces a compression of the terrain in the shape of a column which is concentric with the rod of the bolt. Recent progress in this technique has witnessed the replacement of these expansion bolts by bolts sealed in resin, but three essential operations, that is to say, the drilling of the hole, the positioning of the bolt, and the tightening of the bolt, must still be effected.

Apparatus is known which by itself is capable of successively effecting these three operations. Such apparatus is described in British Patent Specification No. 1,016,125 in the name L.L.Chappuis. It comprises a turret, pivotally mounted on its support and comprising a drilling carriage and a bolting carriage.

The first carriage constitutes a drill allowing a hole to be drilled before the turret rotates, around its pivot shaft in the form of a rod anchored in the "roof" of the gallery, so that the second carriage is brought into a position coaxial with the previously drilled hole to allow introduction and then tightening of the bolt. For positioning resin-sealed bolts the turret may moreover carry an injection device to bring the resin cartridge into a position coaxial with the drilled hole and to insert the cartridge before the fitting of the bolt.

This kind of apparatus allows the bolt fitting operation to be automated. To reduce human intervention still further, with a view to saving labour, to increasing productivity and above all to increasing safety, it has already been proposed that the bolt fitting apparatus be provided with a bolt magazine, as has been described in U.S.Patent No. 3,218,893 issued to R.W.Madison etalon November 23, 1965 and assigned to Gardner-Denver Company. This magazine may contain several bolts which constitute a reserve for several successive fitting operations, and it comprises a feed mechanism allowing the successive advancing of the bolts into register with the axis of the bolt-inserting mechanism.However, the bolt feed mechanism of the known bolt magazine disclosed in the said U.S.Patent No. 3,218,893 is extremely complex, and therefore costly in construction and maintenance, and unreliable.

The present invention aims to overcome these disadvantages by providing a bolt magazine which is very simple in construction, especially as regards its system of sorting and feeding the bolts, and is therefore economical and very reliable in operation.

Accordingly, the present invention provides a bolt magazine for drilling and bolting apparatus used for supporting the "roof" of a gallery, and comprising a turret carrying a drilling carriage and a bolting carriage, said turret being pivotally mounted on a support and comprising: (a) a frame which is fixed to said support; (b) at least two endless chains which are carried by said frame in parallel planes and are drivable synchronously, at least a part of the links of these chains having the shape of claws; and (c) at least one guide which co-operates with the said claws to enable the claws to hold and feed the bolts.

This feed mechanism allows the bolts to be brought successively into the axis of the bolting carriage in a simple way, the movements of the chains being obviously synchronised with the pivoting movements of the turret and with the displacement of the bolting carriage.

Advantageously the frame of the bolt magazine is open on one side while a protective metal sheet covers the entire upper part of the magazine. The open side allows the loading of bolts which are for example held by a guide fixed on the upper part of the frame and an articulated guide located at the lower part of the frame, means being provided to iock the second guide or to release it. The protective metal sheet prevents any debris from falling into the mechanism and thus prevents any accidental stoppage of the bolt feed.

The endless chains must be driven strictly on a synch ronised basis so that the bolts can advance whilst keeping parallel to each other and can be brought exactly into register with the axis of, i.e.

coaxially with, the bolting mechanism.

The bolt magazine may comprise just two endless chains driven on a synchronised basis by means of a single motor carried by the frame, the motor being connected via a bevel gear to transmission shafts and universal joints to respective drive sprockets of the two chains.

Alternatively the bolt magazine may comprise twp endless chains synchronously driven by means of a single motorwhich is connected directly to a drive sprocket of one of the chains, this drive sprocket being connected by means of a transmission shaft and a universal joint to the drive sprocket of the other chain.

Each of the endless chains of the bolt magazine may be a double roller chain, in which case the drive and return sprockets will be double sprockets.

Resorting to this kind of chain limits their flexion and thus increases the rigidity of the mechanism.

Each endless chain may comprise at least one chain section having plain links and an equal number of chain sections whose links have the shape of claws. Thus, for instance, two chain sections of plain chain links are provided alternating with two chain sections with claw shaped chain links. The number of claw pairs of each one of these latter chain sections corresponds to the number of bolts which may be stored in the bolt magazine.

As the chain mechanism feeds the first bolt towards the turret, it is necessary to arrest this first bolt in an accurate position. For this purpose the bolt magazine is conveniently connected to two retractable holding grippers carried by the turret and capable of stopping and holding a bolt, an upper of the holding grippers being capable of pivotal retraction upwardly in the known way and the lower holding gripper being capanble of pivotal retraction either upwardly or downwardly, a spring combined with a stop mechanism being effective to return the lower holding gripper into a substantially horizontal central position. The bolt is thus held at two fixed points by the upper and lower grippers which hold it firmly, but which are capable of retraction to allow the passage of the rising and descending bolting carriage.Another function ofthesegrippers is to hold not only the bolt, but also the chain after the indexing displacement by one step.

In order that the present invention may more readily be understood the following description is given, merely by way of non-restrictive example, with reference to the accompanying schematic drawings, in which: Figure 1 is a side general arrangement view of a bolting carriage provided with a bolt magazine according to the invention; Figure 2 is a top plan view of this turret to an enlarged scale; Figure 3 is a side view of the bolt magazine on its own; Figure 4 is an end view of the magazine; Figure 5 is a horizontal cross-section view of the magazine at a still greater scale, taken along line 5-5 of Figure 3; Figure 6 is a partial side view of one of the endless chains of the magazine; Figure 7 is a detailed view, partly in cross-section, showing the lower retractable gripper; and Figures 8 and 9 are similar views to Figures 3 and 4, respectively, representing a variant of the magazine according to the invention.

In the drawings there can be seen a bolting turret 1 mounted at the end of an arm 2, its inclination being adjustable by means of a jack 3 as shown in Figure 1.

Turret 1 is pivotally mounted on a support 4, for movement about an axis 5, drawn here as vertical, but which is capable of assuming the desired inclination according to the extension of jack 3.

Another jack 6, articulated on the one hand to the support 4 and on the other hand to a point of turret 1, controls the pivoting of the turret 1 around axis 5 in the direction of arrow 7 as shown in Figure 2.

The turret 1 constituted by an H section post 8, which is parallel to the axis 5 and has one of its flanges serving as slide track for a drilling carriage 9 and the otherflange serving as a track for a bolting carriage 10. The axis 11 of the drill and axis 12 of the bolting device 10 are equidistant from the pivot axis 5 of the turret 1. This allows a hole to be drilled and a bolt then to be brought exactly coaxial with the hole, by pivoting of the turret 1 around axis 5 which axis is held rigorouslyfixed byan anchoring rod 13 provided at the top of the turret.

In the embodiment shown in Figures 1 and 2, relating to fitting apparatus for resin-sealed bolts, the turret 1 additionally carries an injection line 14 for resin cartridges situated between the drilling and bolting carriages 9 and lOon the same circular arc 15 as that described by the axes 11 and 12. This injection line 14 allows the cartridges to be introduced into the drilled hole, without any manual intervention, when turret 1 is brought into a position communicating the cartridge line 14 with the drilled hole.

According to the invention, the turret 1 is provided with a bolt magazine 16 which is fixed to the support 4 by means of a fixing component 17.

The magazine 16, which is more clearly seen on Figures 3 to 5, comprises a frame 18 parallel with the turret 1. Frame 18 is open on one side but has a protective metal sheet 19 covering the entire top part of the magazine. In its lower part, the frame 18 comprises a horizontal plate 20. In front of this plate, that is to say, on the open side of the frame, there is mounted a first guide 21, articulated around a horizontal arbor 22 situated below plate 20. A holding device 23, articulated to frame 18 around an arbor 24, locks the guide 21 in the position shown, or releases it so that it can pivot around arbor 22.

Another guide 25 parallel to guide 21 is mounted in a fixed position on the upper part of frame 18.

The device for holding the bolts in combination with the above mentioned guides 21 and 25 as well for feeding the bolts comprises two identical endless chains 26 and 27 situated in parallel and superimposed planes. The two chains 26 and 27 are synchronously driven by means of a single hydraulic motor 28 carried by the frame 18. The output shaft of motor 28 is connected via a coupling 29 to a bevel gear 30 whose output shaft has drive couplings at both ends.

The lower end of the output shaft of bevel gear 30 is coupled by means of a first universal joint 31 to a transmission shaft 32 which in turn is coupled by means of a second universal joint 33 to a double sprocket 34 for driving the lower chain 26. Similarly, the upper end of the output shaft of bevel gear 30 is coupled by means of a first universal joint 35 to a transmission shaft 36 which in turn is coupled by means of a second universal joint 37 to a double sprocket 38 for driving the upper chain 27.

The double drive sprocket 34 of the lower chain 26, as well as the double return sprocket 39 of the same chain are supported on the respective components 40 and 41 forming bearings adjustably mounted on frame 18. Similarly, the double drive sprocket 38 of the upper chain 27 as well as the double return sprocket 42 of the same chain are supported on respective components 43 and 44 forming bearings which are also adjustably mounted on frame 18.

Figures 5 and 6 show in detail the endless chains 26 and 27. They are double roller chains, each comprising two chain sections having ordinary chain links 45 and two chain sections whose chain links 46 have the shape of outwardly extending claws. On each one of these latter chain sections, the claws 46 are grouped in three pairs; the two claws of each pair forming a slot with a substantially circular bottom.

The sections comprising the claw-shaped chain links 46 of the two chains 26 and 27 are strictly superimposed, to allow the bolts 47 to be placed into the corresponding slots of the two chains. The bottom end of each bolt 47 rests on the lower plate 20 of frame 18 while the guides 21 and 25 prevent any lateral movement of the bolt (apart from a limited degree of play).

The bolt 47 is inserted into the magazine via the open side of frame 18 by introducing it in an inclined position, the lower guide 21 being hinged near the bottom. Thus three bolts 47 may be disposed in the magazine 16, this number being obviously linked to the embodiment shown and is not an essenttial characteristic of this invention. After the guide 21 has been raised and locked by means of a holding device 23, the mechanism is ready to function to bring the first bolt 47 into register with the axis 12 of the bolting device, the turret 1 being brought into the Figure 2 position and the bolting carriage 10 being kept in its lower position on the post 8.

The hydraulic motor 28 is actuated so as to turn the two driving sprockets 34 and 38 synchronously in order to advance the two endless chains 26 and 27 at the same speed in the direction of arrow 48 until the first bolt 47 is in register with the axis 12 of the bolting device. In this position the bolt is automatically stopped and taken over by a pair of retractable upper and lower grippers 49 and 50, respectively, carried by the turret 1.

The upper gripper 49, visible in Figure 2, is a known device already used for apparatus not having bolt magazines to hold the bolt to be fitted. It is articulated around an axis 51 to be capable of retraction by pivoting upwardly during the raising of the bolting carriage 10 as the carriage arrives at its end of travel.

The lower gripper 50, shown in detail in Figure 7, is constructed on the same principle as is the upper gripper 49, but so as to be capable of retraction upwardly or downwardly. It comprises two jaws 52 and 53 pivotally mounted around arbors 54 and 55 respectively at the end of a lever 56, the space between the two jaws 52 and 53 forming a slot 57 capable of receiving a bolt. These jaws are sufficiently interspaced to allow the passage of the bolts 47 right upto the end of the slot 57 and they close automatically under the action of a spring 58. The lever 56 is articulated around a shaft 59 on a support 60 which is itself fixed by a collar 61 on turret 1. A spring 62 combined with a stop mechanism of a known type allows the lever 56 to be brought into a substantially horizontal central position after pivot ing around shaft 59 either upwardly or downwardly.

Finally, lever 56 carries a cam follower roller 63 allowing carriage 10 to push it easily upwardly during bolting and then to push it as easily down wardly during the return travel.

When a first bolt 47 has been inserted and anchored in the hole, the chains 26 and 27 of magazine 16 may be displaced to bring a new bolt 47 into register with the axis 12 of the bolting device, this displacement of course being correctly synchro nised with the indexing movement of turret 1 and therefore with the operational cycle comprising the successive operations of drilling, resin-injection and insertion of the bolt. After the three bolts forming one and the same group, that is to say the groups held by the three claws of the same chain section, have been used, the claws of the other chain section appear on the open side of the magazine and this allows the next successive group of bolts to be loaded in the bolt magazine and so on.

Finally, Figures 8 and 9 show an alternative embodiment of the bolt magazine, in this case without the upper protective metal sheet. This embodiment offers better visibility for the operator and incorporates a modified and relatively simplified arrangement since there is no need for parallel drive trains to ensure the synchronous drive of the two endless chains 26 and 27. A motor 28 is disposed in the bottom part of the magazine and is carried by the bearing 41 of the double drive sprocket 39 of the lower chain 26 and coupled directly to this sprocket by means of a tubular coupling. This sprocket 39 is itself coupled by means of a transmission shaft 64 and two universal joints 65 and 66 to the double drive sprocket 42 of the upper chain 27. The two reference numerals 34 and 38 designate here, respectively, the double return sprockets of the lower chain 26 and of the upper chain 27.In all other respects, the magazine is unmodified, and the elements which correspond to those of the embodiment of Figures 1 to 7 are designated simply by the same reference numerals, there being no need for a fresh description.

The invention has been described above in the context of apparatus for the insertion and anchoring of resin-sealed bolts which constitutes one particular application. It is, of course, evident that the invention may equally be applied to apparatus for the fitting of conventional expansion anchorage bolts.

As goes without saying, and as follows from the preceding considerations, the present invention is not limited to the sole embodiments of this bolt magazine which have been described above by way of examples. On the contrary it encompasses all the variants comprising equivalent means, which are covered by the scope of the claims. In particular, the details of the means ensuring the drive of the endless chains may be varied from those of the two systems exemplified.

Claims (9)

1. A bolt magazine for drilling and bolting apparatus used for supporting the "roof" of a gallery, and comprising a turret carrying a drilling carriage and a bolting carriage, said turret being pivotally mounted on a support and comprising: (a) a frame which is fixed to said support; (b) at least two endless chains which are carried by said frame in parallel planes and are drivable synchronously, at least a part of the links of these chains having the shape of claws; and (c) at least one guide which co-operates with the said claws to enable the claws to hold and feed the bolts

2. A bolt magazine according to claim 1, wherein said frame is open on one side and a protective metal sheet covers the entire top part of the magazine.

3. A bolt magazine according to claim 2, wherein there are two said guides, one of which is mounted in a fixed position on the upper part of the frame, and the other is articulated at its lower part and situated on the open side of the frame, means being provided to lock said other guide orto release it in orderto allow the magazine to be loaded by introducing the bolt in an inclined position.

4. A bolt magazine according to any one of claims 1 to 3, wherein there is a motor carried by the frame and there are two said endless chains connected to said motor by means of a bevel gear, two transmission shafts and universal joints, and sprockets to drive the respective two chains.

5. A bolt magazine according to any one of claims 1 to 3, wherein there are two synchronously driveable endless chains and a single motor to drive said chains, said single motor being coupled directly to a drive sprocket of one of the chains and said drive sprocket being connected by means of a transmission shaft and universal joints to a drive sprocket of the other chain.

6. A bolt magazine according to any one of claims 1 to 5, wherein each of said endless chains is constituted by a double roller chain, mounted on two double sprockets serving as drive and return sprockets.

7. A bolt magazine according to claim 6, wherein each endless chain comprises at least one chain section having chain links in the shape of claws, and an equal number of chain sections with plain chain links.

8. A bolt magazine according to any one of claims 1 to 7, and includng: two retractable grippers carried by the turret for stopping and holding a bolt, an upper of said two grippers being capable of retraction by pivoting upwardly in the known way and the lower gripper being capable of retraction by pivoting either upwardly or downwardly; a spring; and a stop mechanism connected to the spring, said spring and said stop mechanism serving to return said lower gripper into a substantially horizontal central position.

9. A bolt magazine for drilling and bolting apparatus used for supporting the "roof" of a mine gallery, such magazine being constructed and adapted to operate substantially as hereinbefore described with reference to, and as illustrated in, Figures 1 to 7, or Figures 8 and 9 of the accompanying drawings.