GB2445581A

GB2445581A - Laser line device

Info

Publication number: GB2445581A
Application number: GB0700623A
Authority: GB
Inventors: Matthew White
Original assignee: B&Q Ltd; Kingfisher PLC
Current assignee: B&Q Ltd; Kingfisher PLC
Priority date: 2007-01-12
Filing date: 2007-01-12
Publication date: 2008-07-16
Anticipated expiration: 2027-01-12
Also published as: GB0700623D0; GB2445581B

Abstract

A line generator for projecting a light line onto a surface, comprising a housing 2 having a centre of gravity lying on a central axis and including an aperture 3 located on the central axis for receiving a surface attachment device and defining a centre of rotation around which the housing can rotate, and a first light source 4, 5 or 6, for emitting a first light line from the housing at a predetermined angle to the central axis; wherein the centre of gravity is displaced from the centre of rotation such that when the generator is mounted on a surface attachment device attached to a surface, the body rotates around the centre of rotation until the central axis is substantially vertical with the centre of gravity lying below the centre of rotation, and the light source is operable to project a light line onto the surface at the predetermined angle.

Description

Laser Line Device

Technical field

1] This invention relates to light line generating devices, in particular to self-levelling devices.

Background art

2] There are many types of laser line generator devices which project laser lines to help with aligning objects or to mark out horizontal or vertical lines on a surface. These devices typically require using bubble vials to ensure that the lines generated are level or comprise internal pendulum assemblies in the housing of the levels.

3] The object of present invention is to provide a self levelling device for projecting a line onto a reference surface.

Disclosure of the invention

4] One embodiment of the invention comprises a line generator for projecting a light line onto a surface, comprising a housing having a centre of gravity lying on a central axis and including an aperture located on the central axis for receiving a surface attachment device and defining a centre of rotation around which the housing can rotate, and a first light source for emitting a first light line from the housing at a predetermined angle to the central axis, wherein the centre of gravity is displaced from the centre of rotation such that when the generator is mounted on a surface attachment device attached to a surface, the body rotates around the centre of rotation until the central axis is substantially vertical with the centre of gravity lying below the centre of rotation, and the light source is operable to project a light line onto the surface at the predetermined angle. With the center of gravity inline but below the center of rotation, the entire line generator acts as pendulum. As the entire line generator is a pendulum, once attached to the surface attachment device, the line generator can rotate about the shaft of the attachment device and self level, with the central axis defining a central axis of mass. Preferably the line generator is a laser level.

5] Preferably the first light source can emit a light line in a substantially horizontal direction when the central axis vertical.

6] The line generator can further comprise a second light source for projecting a second line in a second predetermined direction from the housing. Preferably the second light source can emit a line in a substantially vertical direction. The line generator can also comprise a third light source capable of projecting a third line in a third direction from the housing.

7] The position of the light sources is rotatable so that the direction of the line projected from the housing is adjustable relative to the housing. The light source can be adjusted such that the light is projected from the housing at a specific angle from the housing.

8] Preferably the housing comprises angle markings. The angles marking can be used to set the light source to emit a light beam at a specific angle from the level.

9] It is particularly preferred that the line generator comprises a chassis located inside the housing on which components of the line generator are mounted. The chassis in the housing is non-movably fixed to the housing.

The position of the centre of gravity to be adjusted, for example by means of an adjustable screw in the housing. Relatively heavy components of the generator can be mounted on the chassis, for example one or more batteries or other power supplies are mounted on the chassis. The chassis can further comprise a groove to align the batteries with the central axis of the housing. The groove ensures that the central axis of the batteries is inline with the central axis of the housing to maintain the balance of the housing.

0] The line generator can comprise an attachment device for attaching the level to a surface. Preferably the surface is a wall [0011] Preferably the attachment device comprises a shaft inserted through the aperture on which the line generator can rotate. The attachment device is attached to the surface and the light level hangs from the shaft.

2] Preferably the attachment device comprises a self adhesive pad for attaching the device to a surface. However other means for attaching the attachment device to the surface may be used.

Brief description of the drawings a

[00131 Figure 1 shows a line generator according to one embodiment of the invention attached to an attachment device; Figure 2 shows the cutaway view of a line generator according to one embodiment of the invention; and Figure 3 shows a wall attachment device that can be used with the invention.

4] Figure 4 shows a back view of the wall attachment and adhesive pad that can be used with the invention.

Mode(s) for carrying out the invention [0015] Referring to figures 1 and 2 showing one embodiment of a light line generator according to the invention. The device I comprises a housing 2 with an aperture 3 and light sources 4, 5, 6. With reference to figure 1 the device is attached to the shaft 7 of a surface attachment device 8 through the level's aperture 3. The aperture 3 is located in the top portion of the housing with the centre of rotation lying on the central axis of the laser level. The level is weighted so that the centre of gravity of the device I also lies on the central axis below the aperture 3 which forms the centre of rotation. This arrangement allows the entire device I to act as a pendulum and therefore self level when it is hanging from a wall attachment with the central axis vertical. Although figures 1 and 2 show a device with a symmetrical form, with both the centre of gravity and centre of rotation on the central axis of mass for the device, the line generator can have a non-symmetrical form.

6] The first light source 4 is positioned such that the light source emits a substantially horizontal beam. A second light source 5 is positioned such that the light source can emit a substantially vertical beam. A third light source 6 is positioned such that light source emits a substantially horizontal beam in the opposite direction from the first light source.

Preferably the light beam emitted is converted into a planar beam. A lens structure in the housing converts the light beam to a planar beam, which can exit through windows in the housing. In a further embodiment of the invention the positions of the light sources can be rotated such that the light sources emit a light beam at an angle away from the horizontal or vertical axis of the device 1. The housing can comprise angle markings so that the user can set the light source to emit the light beam at a specific angle away from the horizontal or vertical of the housing.

7] A power supply 9 is located below the aperture 3 and is arranged in the housing 2 such that the centre of gravity of the device I is maintained below the centre of rotation and on the central axis. The power supply contributes to the weight of the device, and therefore contributes to the performance of the entire device as a pendulum. The power supply for the light source can be batteries, which can be replaceable or rechargeable. If small batteries are used, such as small solar rechargeable batteries, weight may be added to provide a lower centre of gravity to the device.

The batteries can be cylindrical, such as AA type battery cells, and are mounted in the device such that their central axis is in the same plane as the central axis of the device. This will allow battery cells with different weights or slightly different diameters to be used, while still maintaining the overall balance of the device and therefore its accuracy. Preferably the groove that the batteries fit is a V shaped so that removable cylindrical batteries of slightly different diameters will align with the central vertical axis of the light level when inserted into the housing.

8] The aperture 3 comprises a bearing 10, such as a ball bearing, however other forms of bearings may be used. The inner race of the bearing rotates around the shaft 7 of the wall attachment 8. This allows the entire body of the laser level I to rotate about the shaft of the wall attachment. The bearing helps prevent the housing from sticking when rotating about the shaft.

9] The various components of the device (light sources 4, 5, 6, power supply 9) are mounted on a chassis 13 that is located inside the housing 2. The device can comprise an adjustable screw 11 to adjust the centre of gravity of the device. The screw Ills accessible even when the device is fully assembled. This allows the balance to be adjusted after the device is manufactured.

[00201 The device may also comprise a bubble vial on the housing to indicate that the light beams are level, i.e. substantially horizontally. 5.

1] Referring to figures 3 and 4 an attachment device 8 that can be used with the line generator comprises a shaft 7 protruding from one side of the base 12. The attachment device 8 is secured to the wall by a pad 14 with an adhesive side. The pad is placed over the attachment device with the shaft protruding through a hole in the pad. The adhesive should be sufficiently low tack so that the pad can be easily removed from the wall, such as a pad of masking tape. It is preferred that the entire back of the pad is not sticky to help with the application and removal of the pad. Alternatively pins may be used to secure the surface attachment to the surface, depending on the surface it is to be attached to or the back of the surface attachment may have an adhesive backing. The shaft may be a cylinder with a closed end. While it is preferred that the line generator is attached to the reference surface using the attachment device, it can alternatively be hung from a wall using a pin or nail attached to the wall and inserted through the aperture.

2] The surface attachment is placed on the wall and an adhesive pad with a hole for the shaft to protrude through is placed over the attachment device to secure the device to the wall. The line generator is then clipped onto the attachment by inserting the shaft through the aperture so that the line generator is hanging off the attachment against the wall. The line generator will emit a laser plane that contacts the wall forming a laser line on the wall. As the entire device acts as a pendulum, hanging it from the wall will result in the device projecting substantially horizontal and vertical lines against the wall.

Claims

Claims 1. A line generator for projecting a light line onto a surface,

comprising a housing having a centre of gravity lying on a central axis and including an aperture located on the central axis for receiving a surface attachment device and defining a centre of rotation around which the housing can rotate, and a first light source for emitting a first light line from the housing at a predetermined angle to the central axis; wherein the centre of gravity is displaced from the centre of rotation such that when the generator is mounted on a surface attachment device attached to a surface, the body rotates around the centre of rotation until the central axis is substantially vertical with the centre of gravity lying below the centre of rotation, and the light source is operable to project a light line onto the surface at the predetermined angle.
2. A line generator according to claim I wherein the first light source can emit a light line in a substantially horizontal direction when the central axis is vertical.
3. A line generator according to any of claims I or 2, further comprising a second light source capable of emitting a second line in a second predetermined direction from the housing.
4. A line generator according to claim 3 wherein the second predetermined direction is aligned with the central axis such that light source can emit a light line in a substantially vertical direction when the generator is mounted on the surface attachment device.
5. A line generator according to any of the preceding claims wherein the light source is rotatable so that the angle of the light line emitted from the housing is adjustable relative to the central axis.
6. A line generator according to any of the preceding claims wherein the housing further comprising angle markings.
7. A line generator according to any preceding claim, further comprising a chassis located inside the housing on which components of the line generator are mounted.
8. A line generator according to claim 7, wherein relatively heavy components of the generator are mounted on the chassis. 7/
9. A line generator according to claim 8, wherein one or more batteries or other power supplies are mounted on the chassis.
10. A line generator according to claim 9 wherein the chassis comprises a groove to align the batteries with the central axis of the housing.
11. A line generator according to any of the preceding claims, further comprising an adjustable screw to adjust the centre of gravity.
12. A line generator according to any of the preceding claims further comprising an attachment device for attaching the level to a surface.
13. A line generator according to claim 12 wherein the attachment device comprises a shaft inserted through the aperture on which the level can rotate.
14. A line generator according to any of claims 12 or 13 wherein the attachment device comprises a self adhesive pad for attaching the device to a surface. * . * .** I... * * * .** * * * S..

S S.. * .. * . . * S * S *.

S

14. A line generator according to any of claims 12 or 13 wherein the attachment device comprises a self adhesive pad for attaching the device to a surface.

Amendments to the claims have been filed as follows Claims 1. A line generator for projecting a light line onto a surface, comprising a housing having a centre of gravity lying on a central axis and including an aperture located on the central axis for receiving a surface attachment device and defining a centre of rotation around which the housing can rotate, and a first light source for emitting a first light line from the housing at a predetermined angle to the central axis; wherein the centre of gravity is displaced from the centre of rotation such that when the generator is mounted on a surface attachment device attached to the surface, the line generator functions as a pendulum and rotates around the centre of rotation until the central axis is substantially vertical with the centre of gravity lying below the centre of rotation, and the light source is operable to project a light line onto the surface at the predetermined angle.

2. A line generator according to claim I wherein the first light source can emit a light line in a substantially horizontal direction when the central axis is vertical.

3. A line generator according to any of claims I or 2, further comprising a second light source capable of emitting a second line in a second predetermined direction from the housing.

4. A line generator according to claim 3 wherein the second predetermined direction is aligned with the central axis such that light source can emit a light line in a substantially vertical direction when the generator is mounted on the surface attachment device.

5. A line generator according to any of the preceding claims wherein the light source is rotatable so that the angle of the light line emitted from the housing is adjustable relative to the central axis.

6. A line generator according to any of the preceding claims wherein the housing further comprising angle markings. *.S

* 7. A line generator according to any preceding claim, further comprising a chassis located inside the housing on which components of the line generator are mounted.

8. A line generator according to claim 7, wherein relatively heavy components of the generator are mounted on the chassis.

9. A line generator according to claim 8, wherein one or more batteries or other power supplies are mounted on the chassis.

10. A line generator according to claim 9 wherein the chassis comprises a groove to align the batteries with the central axis of the housing.

II. A line generator according to any of the preceding claims, further comprising an adjustable screw to adjust the centre of gravity.

12. A line generator according to any of the preceding claims further comprising an attachment device for attaching the line generator to a surface.

13. A line generator according to claim 12 wherein the attachment device comprises a shaft inserted through the aperture on which the line generator can rotate.