GB2474330A

GB2474330A - An increment borer extractor including a chuck

Info

Publication number: GB2474330A
Application number: GB1015358A
Authority: GB
Inventors: Neil James Loader; John Sidney Waterhouse
Original assignee: Individual
Current assignee: Individual
Priority date: 2009-10-07
Filing date: 2010-09-15
Publication date: 2011-04-13
Also published as: GB201015358D0; GB0917602D0

Abstract

A tool for extracting an increment borer 1 from an object such as a tree comprises: a securing means 9 including a thread 11 which clamps rigidly to the object via spikes 93; a chuck 13 having an internal thread to engage the securing means 9 and a clamp to secure to the increment borer shaft 1; an adaptor 300 can rigidly attach chuck 13 to a handle 3. The chuck is designed to be used either with the securing means (fig 5) in which case rotation of the chuck moves it away from the object and withdraws the increment borer; or with the handle so that it can clamp to the shaft of an increment borer whose handle has broken off, and a new handle be attached. The chuck is ideally of collet form.

Description

1 EXTRACTOR DEVICE FOR EXTRACTING AN INCREMENT BORER 3 The present invention relates to devices for extracting increment borers from objects to be 4 cored, kits of parts for such devices and methods of extracting increment borers from such objects.

7 Increment borers are simple tools used to cut cylindrical cores from objects such as trees, 8 telegraph poles and the like. These cores may be used, for example, to determine the age of a 9 tree without cutting the tree down, or to investigate whether or not a pole is rotten in the centre.

12 A typical increment borer, as shown in Figure 1, consists of a hollow,cylindrical, metal shaft 13 1, one end having a sharp cutting rim 5 and a short section 7 of external screw thread, the* 14 opposite end having a removable handle 3 which is normally removable and fitted onto the shaft prior to use. The shaft is bored into or through the object to be cored by clock*ise 16 rotation of the handle, tie screw thread pulling the shaft into the object and the hollow shaft 17 receiving a core of material cut out by the cutting rim. In normal use the core is removed 18 from the borer, which is then withdrawn from the object by anticlockwise rotation.

However, if the threaded portion of the shaft penetrates a rotten or hollow portion of the 21 object, the thread may lose contact with sound material and lose its purchase. The borer 22 caimot then be easily withdrawn. Similarly, if the corer shaft breaks externally whilst in use, 23 it is desirable to remove the borer remnant from the tree. Thus there is a need for a tool to 24 facilitate extraction of a stuck or broken increment borer (or a device having a similar rotational or axial sampling mode) from an object to be cored.

2 Accordingly, a first aspect of the present invention provides an extractor device for extracting 3 an increment borer from an object, the device comprising: 4 a first body which has immobilising means for rotatably immobilising the first body relative to the object, and 6 a second body which is threadingly engaged to the first body and has securing means 7 for releasably securing the second body to the increment borer; 8 whereby, in use, rotation of the second body on the first body causes the second body 9 to move away. from the object in the axial direction of the borer thereby extracting the borer from the object. Thus the borer may be extracted even when the borer does not purchase on 11 the subject.

13 By "threadingly engaged" is meant any suitable construction by which rotational motion is 14 converted into translational motion. Typically the first body is threadingly engaged to the second body by means of complementary screw formations on the first and second bodies.

17 In one embodiment, the first and second bodies comprise coaxial sleeve portions at which the 18 bodiestkreadingly engage and which, in use, surround a portion of the borer projecting from 19 the object. With this embodiment, the handle of the borer may need to be removed in order to slide the sleeve portions onto the shaft of the borer. * 21

* 22 The immobilising means may comprise projections extending from the first body such as 23 spikes or claws for gripping the object. In a preferred embodiment the projections are 24 radially spaced from the longitudinal axis of the borer, which better prevents rotation of the first object relative to the object.

2 Alternative immobilising means may include (i) nails passing through respective holes in the 3 first body, the nails then being driven into the object, or (ii) a belt attached to the first body 4 which can then be tightened around the subject.

6 The securing means comprises a modified chuck having a number of adjustable jaws. In a 7 preferred version the chuck is equipped with an internal screw thread such that the chuck 8 itself constitutes the second body.

In a further embodiment, the second body has a handle or handles which can be used to turn 11 the second body. Thus if for any reason the end portion of the borer is broken off so that the 12 borer handles cannot be used, the handles or handles of the second body can rotate the second 13 body and pull the borer from the object. Preferably the handle or handles are detachably 14 mounted to the second body via the third body (e.g. by engaging a corresponding hole in the second body) so that the handle can be dismounted from the second body when it is not 16 needed.

18 It will be appreciated that the device comprises a number of component parts. Accordingly a 19 further aspect of the present invention provides a kit of component parts for assembly into an extractor device according to the previous aspect. 21 0

22 The present invention further provides a method of extracting an increment borer from an 23 object, comprising the steps of (i) providing an extractor device according to the first aspect 24 of the present invention, (ii) rotatably immobilising the first body with respect to the object and securing the second body to the borer, and (iii) rotating the second body, whereby the 1 second body moves away from the object in the axial direction of the borer, thereby 2 extracting the borer frOm the object.

4 A specific embodiment of the present inveniion will now be described, by way of example only, with reference to the accompanying drawings in which: 7 Figure 1 shows an increment borer, 8 Figure 2 is a side view of an extractor device embodying the present invention, 9 Figure 3 is a top view of the device shown in Figure 2, Figure 4 is a further side view of the device shown in Figure 2, 11 Figure 5 illustrates the operation of an extractor device according to the present invention 12 (mode 1), 13 Figure 6 is a side view of an adaptor(third body), 14 Figure 7 is a top view of the adaptor (third body), and Figure 8 illustrates the operation of an extractor device according to the present invention 16 (mode 2).

18 Referring to Figures 2 to 4, an extractor device has a rectangular or circular base plate 9 with 19 claws 93 extending forwardly from the corners thereof. A hollow, cylindrical, inner sleeve 11 extends rearwardly from the base plate and has an external screw thread 111. An outer 21 sleeve, comprising a threaded chuck 13, is screwed over the end of the inner sleeve by means 22 of a complementary internal thread 131, the length of which equates with the length of the 23 thread 111. Thus the chuck moves axially along the inner sleeve when the two sleeves are 24 rotated relative to one another.

1 At the end of outer modified chuck 13 furthest from base plate 9 are three adjustable jaws 15 2 which, by tightening with a key 151, can ensure secure contact with the shalt of an increment 3 borer (which, as described below, in use extends to grip the shaft of the borer) without 4 causing damage to the borer.

6 Figure 5 illustrates the mode of operation of the extractor device (mode 1). When a borer 7 (such as that shown in Figure 1) is bored into a tree 200 and threaded portion 7 of the borer 8 penetrates a rotten portion (indicated by shading in Fig. 5) of the tree, the threaded portion 9 may lose purchase on the tree so that the borer cannot be extracted (or indeed further penetrated into the tree). To extract the borer using the extractor device, handle 3 of the borer 11 is first removed from shaft 1, inner sleeve 11 and chuck (outer sleeve) 13 of the extractor 12 device are slipped along the shaft, and the handle is replaced.

14 The device is slipped along shaft 1 until claws 93 engage the bark of the tree. Outer sleeve 13 (modified chuck) is screwed along inner sleeve 11 up to base plate 9, and jaws 15 are then 16 tightened by means of key 151 to clamp the outer sleeve onto the shaft of the borer.

18 Handle 3 of the borer is then rotated anticlockwise, i.e. in the direction which would 19 ordinarily achieve withdrawal from the tree. This causes outer sleeve 13 (modified chuck) to rotate with respect to inner sleeve 11. The inner sleeve cannot itself rotate, because claws 93 21 of base plate 9 are engaged with the bark of the tree. Thus the rotation causes the outer 22 sleeve (modified chuck) to be drawn along the inner sleeve away from the base plate, pulling 23 the borer with it.

1 When thread 7 on the borer shaft re-engages with sound wood, the borer continues to 2 withdraw from the tree by virtue of its own screw thread, and base plate 9 then disengages 3 from the trunk. Once the borer is completely withdrawn from the tree, the extractor device 4 can be slipped off the threaded end of the borer shaft simply by loosening the jaws 15 of the outer sleeve 13 (modified chuck).

6 Referring to Figures 2 to 7, an extractor device has an outer sleeve, comprising a threaded 7 chuck 13, with means for attaching a handle (Fig 6,7).

9 At the end of outer modified chuck 13 furthest from base plate 9 are three adjustable jaws 15 which, by tightening with a key 151, can ensure secure contact with the shaft of an increment 11 borer (which, as described below, in use extends to grip the shaft of the borer) without 12 causing damage to the borer.

14 Figure 8 illustrates the mode of operation of the extractor device (mode 2). When a borer (such as that shown in Figure 1) is bored into a tree 200 and the shaft of the borer breaks 16 preventing attachment of the handle, the remaining section of borer shaft embedded in the 17 tree cannot be extracted (or indeed further penetrated into the tree). To extract the broken.

18 borer 313 using the extractor device, handle 3 of the borer is first removed from the broken 19 section of shaft 1, an adaptor 300 is attached to the chuck (outer sleeve) 13 of the extractor device (by means of inserting lugs 311 into holes 312 in the end section of the chuck, and 21 slipped along the shaft, and the handle 3 is attached to the end of the adaptor.

23 The assembly is slipped along shaft 1 until sufficient amount of the protruding shaft enables 24 the jaws (15) of the outer sleeve 13 (modified chuck) to be tightened by means of key 15 Ito clamp the outer sleeve onto the shaft of the borer.

I

2 Handle 3 of the borer is then rotated anticlockwise, i.e. in the direction which would 3 ordinarily achieve withdrawal from the tree. This causes outer sleeve 13 (modified chuck) 4 and attached adaptor to rotate together. Thus the rotation causes the outer sleeve (modified chuck) to rotate the threaded section of the borer remaining within the tree, pulling the broken 6 borer with it.

8 Once the borer is completely withdrawn from the tree, the extractor device can be slipped off 9 the threaded end of the borer shaft simply by loosening the jaws 15 of the outer sleeve 13 (modified chuck), detaching the adaptor and removing the handle unit.