CA2540719A1

CA2540719A1 - Laser alignment system

Info

Publication number: CA2540719A1
Application number: CA002540719A
Authority: CA
Inventors: Ian Mckay
Original assignee: Mortlach Holdings Pty Ltd; Ian Mckay
Current assignee: Mortlach Holdings Pty Ltd
Priority date: 2003-09-08
Filing date: 2004-09-08
Publication date: 2005-03-17
Also published as: WO2005024342A1

Abstract

A laser alignment system (10) comprises a body (12) housing a laser system emitting three laser beams (14a, 14b and 14c); and a mounting (16) to which the body (12) is connected. The mounting (16) comprises a course alignment adjustment mechanism (18) allowing the body (12) to be moved about a point (20), and a fine alignment adjustment mechanism (22) for adjusting the position of the point (20). The course alignment adjustment mechanism (18) is in the form of a ball (24) and a clamp (34) that can selectively clamp and release the ball (24). The fine alignment adjustment mechanism (22) comprises three threaded shafts (66) that can be screwed along their respective longitudinal axis to move the position of the point (20).

Description

Laser Alignment System Field of the Invention The present invention relates to a laser alignment system of the type used for marking a line or grade for a tunnel or channel in mining or civil construction.
Background of the Invention When excavating tunnels particularly tunnels of considerably length, it is common to use a laser to assist in directing the excavation in terms of direction and/or grade. The laser is typically mounted on a side wall of the tunnel.
In order to allow checking of the alignment of a laser, a chain is suspended from a back of the tunnel in line with the laser beam so that the beam projects onto the chain at a particular point on the chain. This point is marked with paint or some other type of marker. The chain is then swung out of the way of the laser beam and attached to a side wall of the tunnel. From time-to-time when it is desired to re-check the alignment of the beam, the chain is detached from the side wall and freely suspended.
If the laser beam is in correct alignment then it will again project on the point previously marked on the chain.
If the beam does not strike that point it may be concluded that the beam has been moved out of alignment. However it may also be the case that the chain is not suspended along exactly the same line along which it lay when the point was originally marked on the chain. Accordingly there is some uncertainty as to whether or not the laser is actually correctly aligned.
The present invention was developed to provide an alternate laser alignment system.
In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as °comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention.
Summary of the Invention According to the present invention there is provided a laser alignment system comprising:
a body housing a laser system emitting at least one laser beam;
a mounting to which the body is connected, the mounting comprising a course alignment adjustment mechanism allowing said body to be moved about a point and a fine alignment adjustment mechanism the fine alignment adjustment mechanism operable to adjust the position of the point.
Preferably the course alignment adjustment mechanism includes a ball to which the body is connected and a clamp for selectively clamping and releasing the ball.

Preferably the fine alignment adjustment mechanism comprises a base and at least one member coupling the base to the clamp, the member operable to change the position of the clamp relative to the base.
Preferably the fine alignment adjustment mechanism comprises a resilient member acting to bias the clamp away from the base.
Preferably the fine alignment adjustment mechanism comprises two members coupling the base to the clamp each of the members operable to change the position of the clamp relative to the base.
Preferably the fine alignment adjustment mechanism comprises three members coupled between said base and said clamp, the members spaced about the resilient member and operable to change the position of the clamp relative to the base.
Preferably each of the members is threadingly engaged at at least one end to one of the base and the clamp whereby screwing of any member causes the clamp to move relative to the base.
Preferably the laser system emits at least two laser beams in mutually orthogonal directions.
Most preferably the laser system emits three laser beams in mutually orthogonal directions.

Preferably the alignment apparatus further comprises a control circuit for controlling the laser system, the control circuit incorporating a receiver circuit for receiving a control signal transmitted from a remotely located transmitter.
Preferably the control circuit further comprises an electrical power storage device.
Preferably the control circuit further comprises a timer for turning the laser system ON for a predetermined time upon receipt of the control signal and subsequently turning the laser system OFF after said predetermined time.
In one embodiment the control circuit is disposed within the body. However in an alternate embodiment the control circuit is physically separate from the body, but is electrically connectable to the laser system.
Brief Description of the Drawings Embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings in which:
Figure 1 is a side view of an embodiment of the laser alignment system;
Figure 2 is an exploded view of a mounting incorporated in the alignment system;

Figure 3 is a plan view of a socket member of the alignment system.
Figure 4 is an exploded view of a laser housing incorporated in the alignment system;
Figure 5 illustrates the use of an embodiment of the laser alignment system; and, Figure 6 is a schematic representation of a further embodiment of the laser alignment system.
Detailed Description of Preferred Embodiments Referring to the accompanying drawings, an alignment laser system 10 in accordance with an embodiment of this invention comprises a body 12 housing a laser system emitting at least one, though most preferably three, laser beams 14a, 14b and 14c; and a mounting 16 to which the body 12 is connected. The mounting 16 comprises a course alignment adjustment mechanism 18 allowing the body 12 to be moved about a point 20, and a fine alignment adjustment mechanism 22 for adjusting the position of the point 20.
The course alignment adjustment mechanism 18 comprises a ball 24 which is formed with an integral neck 26 and planer flange 28. The ball 24 is connected to the body 12 by three screws 30 (see Figure 3) that are received in holes 32 formed in the flange 28. A clamp 34 selectively clamps and releases the ball 24. The mechanism 18 is essentially in the form of a releasable ball joint, with the point 20 at the geometric centre of the ball 24. The clamp 34 comprises an outer locking case 36 that has an opening 38 at one end through which the neck 26 and flange 28 extend. The opening 38 is of a diameter smaller than the diameter of the ball 24. The clamp 34 also includes a socket member 40 that is housed within the locking case 36 and has a recess 42 for seating the ball 24. An upper end of the member 40 is formed with a diametrically extending channel 44 so that the upper portion of the member 44 is effectively bifurcated (see Figure 3).
A transverse hole 46 is formed in the member 40 and has a first length 48 of a first inner diameter and a second length 50 of a smaller inner diameter. Its sheath 52 is seated within the portion 48. A locking screw 54 passes through a hole 56 formed in the side of the locking case 36 and received within the sheath 52 and extends into and threadingly engages the portion 50 of the hole 46.
Turning the locking screw 54 in one direction has the effect of squeezing the bifurcation about the ball 24 thereby preventing it from moving within the recess 42 and clamping it into position. Turning of the screw 54 in an opposite direction releases the bifurcation allowing the ball 24 to move.
The locking case 36 is closed by a base plate 58 that is screwed to a peripheral flange 60 of the locking case 36 by screws 62.
~nlhen the clamp 36 is released the ball 34 can rotate within the recess 42 and casing 36 about point 20 enabling corresponding movement of the body 12. This rotational movement can be resolved about three orthogonal axes radiating from the point 20.

_ 7 _ The fine alignment adjustment mechanism 22 includes a base 64 in the form of a rectangular plate and at least one, in this embodiment three, members 66 that couple the base 64 to the clamp 34 (via the base plate 58). The members 66 are in the form of threaded shafts each of which is provided with an intermediate adjustment wheel 67 that can be grabbed by a persons hand to rotate the members 66 about their longitudinal axis and thus screw the members 66 into and out of the base plate 58. The members 66 are positioned at the corners of an imaginary equilateral triangle.
A resilient member in the form of a spring 68 acts to bias the clamp 34 away from the base 64. However in an alternate embodiment the resilient member can be in the form of a block of resilient material such as rubber.
The head of each member 66 sits in a corresponding hole 70 formed in the base 64 while their opposite ends 71 threadingly engage corresponding holes 72 in the base plate 58. When initially assembling the system 10, the members 66 are passed through the holes 70 in the plate 64 and the wheels 67 then screwed onto and fixed to the members 66. The members 66 are then screwed into the holes 72 so that their opposite ends 74, each of which include a transverse hole 76, protrudes from the base plate 58. Split pins 78 are inserted in the holes 76 to prevent the members 66 from being withdrawn from the holes 72. By turning selected ones of the members 66 the position of the base plate 58 and thus the point 20 can be varied. This in turn provides a fine adjustment of the position of the laser beams 14a, 14b, and 14c. Moreover, _ g _ adjustment of the members 66 allows the plane containing the base plate 58 and thus the point 20 to be tilted in a controllable manner.
Referring in particular to Figure 4, the body 12 comprises a main cylindrical housing 80 having a first compartment 82 at one end, a second compartment 84 at an opposite end and a substantially solid portion 86 between the compartments 82 and 84. The compartment 82 houses a battery 88 for powering lasers 90a, 90b and 90c. This compartment is closed by a screw cap 94 that engages a thread 96 formed on an inner circumferential surface of the housing 80 at the end adjacent the compartment 82.
The cap 94 is provided with three holes 98 which receive the screws 30 which attach the body 12 to the mounting 16 and in particular the ball 24.
The portion 86 is provided with a longitudinally extending cylindrical cavity 100, a first radial cavity 102 that extends between the cavity 100 and opens onto an outer surface 104 of the body 12 and a further radial cavity 106 that also extends from the cavity 100 to the outer surface 104 but is perpendicular to the cavities 100 and 104. The laser 90b is held within the cavity 106 while the laser 90c is held within the cavity 102. Lens covers 108 and 110 seal the lasers 90b and 90c into cavities 106 and 102 respectively.
A cylindrical insert 112 is housed within the compartment 84 and houses a circuit motherboard 92 and the laser 90a.
The laser 90a passes centrally through a hole formed in a plate 93 supporting the motherboard 92. A back end of the laser 90a is received within the cavity 100.

_ g _ The insert 112, motherboard 92 and laser 90a are held within the compartment 84 by a cap 118 that is formed with a thread on its outer circumferential surface that engages a thread 119 formed on an inner circumferential surface of the body 12 in compartment 84. The end cap 118 is formed with an internal shoulder 120 that seats a lens 122 through which the laser beam 14a from laser 90a passes.
The lens 122 is held in place against the shoulder 120 by an annular ring 124. When the cap 118 is screwed into the body 12, it is screwed down to a position where it holds the insert 112 against the portion 86 with the ring 124 abutting an opposite side of the insert 112 and clamping the lens 122 against the shoulder 120.
Power from the battery 88 held within the compartment 82 is supplied to the lasers 90a, 90b and 90c and the motherboard 92 via wires (not shown) which pass through a hole 126 formed in an end of the cavity 100 adjacent the compartment 82.
It is envisaged that the motherboard 92 will include a control circuit for switching the lasers 90a, 90b and 90c ON and OFF, and a receiver circuit for receiving an electromagnetic signal from a remote transmitter to control the control circuit. This allows a user to turn all the lasers 90 ON and OFF remotely using a hand-held transmitter (not shown). Moreover the control circuit may include a timer for turning the lasers 90 ON for a predetermined time upon receipt of the control circuit and subsequently turning the lasers 90 OFF after that time.
The laser beam 14a may be considered as the main laser beam and is used for providing an indication of line and/or grade of a tunnel being excavated. The laser 90b and 90c can be of lower power and are used for checking the alignment of the laser beam 14a.
Figure 5 depicts the system 10 mounted via a bracket 126 to a side wall 128 of a tunnel 130. The body 12 is orientated via the course alignment adjustment mechanism 18 and fine alignment adjustment mechanism 22 so that the beam 14a extends along a desired line and grade of the tunnel 130. Once the beam 14a has been correctly orientated, the points 132b and 132c where the laser beams 14b and 14c respectively strike the inner surface of the tunnel 130 are marked, for example with paint. During tunneling, the laser 90a which produces the beam 14a can be turned ON and OFF remotely when desired or required to ensure that the tunneling is progressing along the correct line and grade. Simultaneously, in order to ensure that the line and grade marked by the laser beam 14a is correct, an operator checks that beams 14b and 14c strike the points 132b and 132c. If they do, then beam 14a can be taken as denoting the correct line and grade of the tunnel. In the event that one or both of the beams 14b and 14c do not strike the points 132b and 132c respectively it is assumed that the laser beam 14a is out of alignment. In such an instance, an operator can manipulate the course and fine alignment adjustment mechanisms 18 and 22 to place the beams 14b and 14c back onto the points 132b and 132c thereby re-aligning the beam 14a along the correct line and grade.
Figure.6 illustrates a further embodiment of the laser alignment system 10 where features which correspond to features of the earlier embodiments are denoted by the same reference numbers. The laser alignment system 10 depicted in Figure 6 is functionally identical to that of Figure 1 however has the following structural variations.
The adjustment wheels 67 are now formed at an end of the shafts 66 on a side of the base plate 64 distant the base plate 58. This allows a scaling down in size of the system 10 while allowing a user to still physically hold and turn the adjustment wheels 67. Having the adjustment wheels 67 between the plates 58 and 64 as in~Figure 1 can make gripping the wheels 67 problematic in smaller models of the system 10. A bracket (not shown) is used to attach the base plate to a structure such as the wall of a tunnel in a manner to allow a user to easily access the wheels 67. In a further variation from the embodiment shown in Figure 1, the resilient member 68 is now in the form of a block of resilient material such as rubber instead of being in the form of a spring.
The final significant variation in the embodiment shown in Figure 6 is that the battery 88 and motherboard 92 have been taken out of the body 12 and placed in a separate removable power and control unit 140 which is demountably supported on the base plate 58. Power is provided to the lasers 14 from the unit 140 via an electrical plug and socket arrangement 142 the plug being at the end of an electrical cable extending from the power control unit 140, and a socket being at the end of an electrical cable extending from the body 12. A hand-held transmitter 144 is used to send control signals 146 which are received by the receivers circuit on the motherboard in the unit 140 and used to provide power to the lasers 14 via the plug and socket 142.

Placing the battery 88 and motherboard 92 in the separate power control unit 140 enables the size of the system 10 depicted in Figure 6 to be scaled down. In particular, the body 12 is substantially shorter than the embodiment depicted in Figure 1 and is a simpler construction and internal form than that shown in Figure 4 as it now essentially only houses the three lasers 90a, 90b and 90c for producing the laser beams 14a, 14b and 14c. Also, the lasers 90b and 90c are offset from each other so that their respective beams do not lie on the same plane. This embodiment allows a potential reduction in overall cost where the user may require multiple systems 10 at different spaced apart locations but that may not require to be operated simultaneously. In this way, a single power control unit 140 may be used for multiple spaced apart systems 10.
Modifications and variations of the above described embodiments which should be obvious to a person of ordinary skill in the art are deemed to be within the scope of the present invention the nature of which is to be determined from the above description and the appended claims.

Claims

1. A laser alignment system comprising:
a body housing a laser housing system emitted at least one laser beam;
a mounting to which the body is connected, the mounting comprising a course alignment adjustment mechanism allowing said body to be moved about a point and a fine alignment adjustment mechanism, the fine alignment adjustment mechanism operable to adjust the position of the point.

2. A laser alignment system according to claim 1 wherein the course alignment adjustment mechanism includes a ball to which the body is connected and a clamp for selectively clamping and releasing the ball.

3. A laser alignment system according to claim 2 wherein the fine alignment adjustment mechanism comprises a base and at least one member coupling the base to the clamp, the member operable to change the position of the clamp relative to the base.

4. A laser alignment system according to claim 3 wherein the fine alignment adjustment mechanism comprises a resilient member acting to bias the clamp away from the base.

5. A laser alignment system according to claim 3 or 4 wherein the fine alignment adjustment mechanism comprises two members coupling the base to the clamp of each of the members operable to change the position of the clamp relative to the base.

6. A laser alignment system according to claim 3 or 4 wherein the fine alignment adjustment mechanism comprises three members coupled between said base and said clamp, the members spaced about the resilient member and operable to change the position of the clamp relative to the base.

7. A laser alignment system according to any one of claims 3-6 wherein each of the members is threadingly engaged at at least one end to one of the base and the clamp whereby screwing of any member causes the clamp to move relative to the base.

8. A laser alignment system according to any one of claims 1-7 wherein the laser system emits at least two laser beams in mutually orthogonal directions.

9. A laser alignment system according to any one of claims 1-7 wherein the laser system emits three laser beams in mutually orthogonal directions.

10. A laser alignment system according to any one of claims 1-9 further comprising a control circuit for controlling the laser system, the control circuit incorporating a receiver circuit for receiving a control signal transmitted from a remotely located transmitter.

11. A laser alignment system according to claim 10 wherein the control circuit further comprises an electrical power storage device.

12. A laser alignment system according to claim 10 or 11 wherein the control circuit further comprises a timer for turning the laser system ON for a predetermined time upon receipt of the control signal and subsequently turning the laser system OFF after said predetermined time.

13. A laser alignment system according to any one of claims 10-12 wherein the control circuit is disposed within the body.

14. A laser alignment system according to any one of claims 10-12 wherein the control circuit is physically separate from the body, but is electrically connectable to the laser system.