GB2125713A

GB2125713A - Drill rod guide for extension rod drilling apparatus

Info

Publication number: GB2125713A
Application number: GB08320662A
Authority: GB
Inventors: Jarmo Heinonen; Rauno Rajala; Ossi Paivalanen
Original assignee: Tampella Oy AB
Current assignee: Tampella Oy AB
Priority date: 1982-08-31
Filing date: 1983-08-01
Publication date: 1984-03-14
Also published as: GB8320662D0; FI64837B; FI823008A0; ZA835742B; FI64837C; SE8304680L; DE3331181A1; SE8304680D0; FR2532358A1

Abstract

The guide (5) comprises a frame (6) mountable on the drill feed beam (3) two guide elements (9, 10) mounted on the frame (6) and locatable on opposite sides of a drill rod (13) to form a guide opening (12) for the drill rod (13), the elements (9, 10) being spaced apart in the direction of the guide axis (A) to form between them a free through slot (14) transverse to the guide axis (A) and having a width (L) greater than the width (Hj) of the drill coupling sleeve (15). The elements (9, 10) are returnably pivotable by means (16) engaged therewith, around a pivot shaft perpendicular to the guide axis (A) from the guiding position shown to a releasing position in which the transverse slot (14) becomes aligned with the axis (A) so permitting passage of the coupling sleeve (15) therethrough. The pivoting means (16) is mounted in use in the path of drill member (2), and is displaceable in the direction of guide axis (A), so that member (2) actuates the pivoting means (16) to pivot the elements (9, 10) to the releasing position as member (2) approaches the guide (5) during drilling. <IMAGE>

Description

SPECIFICATION Drill guide for an extension rod drilling apparatus The present invention relates to a drill rod guide for an extension rod drilling apparatus comprising -a frame mountable on a feeding beam of the drilling apparatus, -two guide elements located on opposite sides of a drill rod and supported by said frame, said guide elements together forming a guide opening for supporting said drill rod, and -a pivoting means in engagement with said guide elements for pivoting said elements with respect to said frame from a guiding position in which said guide elements form said guide opening to a releasing position in which the guide elements open said guide opening for the passage of a coupling sleeve of said drill rod, and back to said guiding position.

Finnish Patent Specification 21 5,1 54 and U.S. Patent Specification 2,734,724 describe drill guides which must be separately opened when the extension sleeve of the drill rod reaches the guides. The drill guides comprise two guide elements which are supported by a frame and displaceable or pivotable towards each other to a guiding position and away from each other to a releasing position by means of a pressure fluid cylinder. The drill guides are complicated in construction and require an expensive pressure fluid operated control circuit.

German Patent Application 29 51 382 discloses a drill guide which can be opened and closed manually whereby it remains during drilling as a barrier in front of the coupling sleeve. The drill guide comprises a U-shaped bow fastened to a frame by means of a pin and a lock washer. Thus, the opening and closing of the drill guide is difficult and time consuming.

U.S. Patent Specification 2,727,725 describes a drill guide which while pushed by the coupling sleeve, is pivoted forwards in the direction of the feeding beam out of the way of the coupling sleeve. A drill guide of this type requires a rather large space. The guide comprises a guide arm pivotally mounted in a frame, the upper U-shaped end of said guide arm forming a guide slot for the drill rod. A latch arm closing the guide slot is pivotally mounted in one shank of the upper end.

When the coupling sleeve pushes the guide arm forwards, the drill rod presses the latch arm into an open position whereby the drill rod is disengaged from the guide slot and the drill guide is pivoted out of the way of the coupling sleeve. The drill guide is provided with an actuator comprising a pressure fluid cylinder by means of which the guide arm is pivotable both to a guiding position and a releasing position. The guide arm is not automatically raised to the guiding position as the drill machine is displaced backwards.

The object of the present invention is to provide a drill guide which avoids the above mentioned disadvantages and which, at the final drilling stage, in order to permit a maximum utilization of the effective length of the drill rod, automatically is displaced out of the way of the connecting sleeve to the releasing position and which, when displacing the drilling machine backwards, automatically returns to the guiding position.This object is achieved by means of a drill guide according to the invention which is characterized in that -said guide elements are located in the direction of the axis of said guide opening at a distance from each other and form between the elements a transverse free through slot having a width greater than the width of said coupling sleeve, -said guide elements are pivotable around a pivot shaft perpendicular to the axis of said guide opening over an angle corresponding to the angle between the axis of said guide opening and the direction of said through slot, and -said pivoting means is mounted to be located in the path of movement of a member, which is provided in the drilling apparatus and is displaceable during drilling in the direction of the axis of said guide opening, so that said member, when approaching the drill guide, actuates said pivoting means for pivoting said guide elements to said releasing position.

The invention is based on the idea of making the drill guide in the manner of a carrousel which in one rotary position forms a guide opening guiding the drill rod and in a second rotary position forms a through slot permitting the passage of the coupling sleeve, whereby the guide elements of the drill guide need not be displaced with respect to each other but only pivoted as one unit with respect to the frame. This permits the use of a simple pivoting means receiving its operating power from the feed movement of the drilling apparatus so that the pivoting means automatically pivots the guide elements away from the guiding position to the releasing position as the coupling sleeve approaches said elements and similarly automatically pivots the guide elements back to the guiding position as the coupling sleeve is displaced away from the drill guide.In this way, the need for separate pressure fluid operated pivoting means is eliminated.

The invention will be described in more detail in the following with reference to the accompanying drawings, in which Figures 1 and 2 are side views of a drilling apparatus provided with drill guides according to the invention and illustrate the operating principle of the drill guide in the guiding position and releasing position, respectively, Figures 3 and 4 are top views on an enlarged scale of the drill guides in the positions shown in Figs. 1 and 2, Figures 5 and 6 show the drill guide as seen in the drilling direction and from above, respectively, while the guide is in the guiding position, Figures 7 and 8 show the drill guide as seen in the drilling direction and from above, respectively, while the guide is in the releasing position, and Figures 9 and 10 are sections of an alternative embodiment of the actuating means of the guide.

Figs. 1 and 2 show a drilling apparatus comprising a drilling machine 1 supported by a carriage 2 displaceable by means of a feed mechanism (not shown) along a feeding beam 2. A fixed drill guide 5 according to the invention is mounted at the front end of the feeding beam, i.e. the end facing a rock 4.

Between the drill guide and the drilling machine is mounted an intermediate guide 5' which is identical with the drill guide located at the front end except that the intermediate guide is displaceable along the feeding beam.

The drill guide 5 comprises a frame 6 intended to be fastened to the feeding beam.

To the frame is pivotally mounted by means of a pivot shaft 7 a plate-like support 8 which supports two upwardly extending parallel plate-like guide elements 9, 1 0. The guide elements are located on opposite sides of the drill rod and form semicircular guide grooves facing opposite directions and forming together a closed guide hole 1 2 when the guide elements are viewed in the direction of the common axis A of the guide grooves, as shown in Fig. 5. The diameter Ho of the guide hole is somewhat larger than the diameter Hp of the drill rod 13, Fig. 3. The guide elements need of course not form a closed hole, but the hole can be replaced, for example, by a slot which in its upper part is provided with inwardly extending projections which hold the drill rod in place.

The guide elements are located in the direction of the axis A of the guide hole at such a distance from each other that a free through slot 1 4 is formed between said elements having a width L somewhat larger than the diameter Hj of a coupling sleeve 1 5 of the drill rod, Fig. 4. Thus. the drill guide can be pivoted over an angle S between the axis A of the guide hole and the direction B of the through slot.

The drill guide is provided with an actuating means 1 6 comprising an actuating rod 1 7 which is mounted axially slideably in a bore in the frame 6. The actuating rod is provided with a toothing 1 8 which is in engagement with a toothing 1 9 in the pivot shaft 7. A spring 20 provided p the frame tends to push the actuating rod outwards, i.e. to maintain the support 8 pivoted in the guiding position shown in Fig. 6. The actuating rod is mounted in the frame in parallel with the axis of the drill rod 13.

The drill guide is mounted on the feeding beam 3 so that the axis A of the guide hole 1 2 formed by the guide elements is concentric with the drill rod 1 3 when the guide elements are located in the guiding position shown in Figs. 3, 5 and 6 whereby the push rod 1 7 is located in a projecting position. In the guiding position, the guide elements surround the drill rod while guiding it during drilling. As the drilling advances and the drilling machine approaches the drill guide, the carriage is pressed against the actuating rod 1 7 of the drill guide or, as shown in Fig. 2, first against the intermediate guide 5' and by means of said guide against the actuating rod of the drill guide 5.Because of this, the rod is pushed into the frame of the drill guide whereby the toothings force the support 8 to rotate 90 around the pivot shaft 7 to the releasing position shown in Figs. 4, 7 and 8 in which the coupling sleeve is free to pass into the through slot 1 4 between the guide elements so that the drilling can be carried out as far as possible inspite of the drill guide.

When the drilling machine and the coupling sleeve is displaced backwards along the feeding beam, the spring pushes the actuating rod outwards while returning the guide elements to the guiding position. The same operations occur in the intermediate guide 5'.

It will be noted that the drill guide opens automatically when the coupling sleeve arrives at the drill guide and returns automatically to the guiding position when the drilling machine is displaced backwards. The feeding movement of the drilling machine is utilized for opening the drill guide and the closing is achieved by means of the spring.

Figs. 9 and 10 illustrate a second embodiment of the actuating means. In this embodiment, the toothings 18, 1 9 are replaced by a pivot cam 21 fastened to the pivot shaft 7 and by a notch 22 which is formed in the actuating rod 1 7 and into which the pivot cam extends.

The drawings and the specification relating thereto are only intended to illustrate the idea of the invention. In its details the drill guide according to the invention may vary within the scope of the claims.

Claims

1. A drill rod guide for an extension rod drilling apparatus, said drill guide (5; 5') comprising -a frame (6) mountable on a feeding beam (3) of the drilling apparatus, -two guide elements (9, 10) located on opposite sides of a drill rod and supported by said frame, said guide elements together forming a guide opening (12) for supporting said drill rod (13), and -a pivoting means (16) in engagement with said guide elements for pivoting said elements with respect to said frame from a guiding position in which said guide elements form said guide opening to a releasing position in which the guide elements open said guide opening for the passage of a coupling sleeve (15) of said drill rod, and back to said guiding position, characterized in that -said guide elements (9, 10) are located in the direction of the axis (A) of said guide opening at a distance from each other and form between the elements a transverse free through slot (14) having a width (L) greater than the width (Hj) of said coupling sleeve (15), -said guide elements are pivotable around a pivot shaft (7) perpendicular to the axis of said guide opening over an angle corresponding to the angle (a) between the axis (A) of the guide opening and the direction (B) of said through slot, and -said pivoting means (16) is mounted to be located in the path of movement of a member (2), which is provided in the drilling apparatus and is displaceable during drilling in the direction of the axis (A) of said guide opening (12), so that said member (2), when approaching the drill guide, actuates said pivoting means (16) for pivoting said guide elements (9, 10) to said releasing position.

2. A drill guide according to claim 1, characterized in that said guide elements (9, 10) are fixedly fastened to a support (8) which is rotatably mounted on the frame (6) by means of a pivot shaft (7) located in the middle of said guide elements.

3. A drill guide according to claim 1 or 2, characterized in that said pivoting means (16) is mounted on said frame (6) and provided with an actuating rod (17) extending from the frame in parallel with the axis of said drill rod.

4. A drill guide according to claim 2 and 3, characterized in that said actuating rod (17) is connected in engagement with said pivot shaft (7) by means of a coupling means (18, 19; 21, 22) which converts the axial movement of said actuating rod into a rotary movement of said pivot shaft.

5. A drill guide according to claim 4, characterized in that said coupling means comprises a tooth rack-tooth ring mechanism (18, 19).

6. A drill guide according to claim 4, characterized in that said coupling means comprises a pivot level-notch mechanism (21, 22).

7. A drill guide according to claim 3, characterized in that said actuating rod (17) is located in the path of movement of a carriage (2) of a drilling machine (1).