GB2348494A

GB2348494A - Gradient indicating device

Info

Publication number: GB2348494A
Application number: GB0006016A
Authority: GB
Inventors: Arnim Fiebig; David Matzo
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 1999-03-31
Filing date: 2000-03-13
Publication date: 2000-10-04
Anticipated expiration: 2020-03-13
Also published as: DE19914539B4; DE19914539A1; GB2348494B; FR2791769A1; GB0006016D0; FR2791769B1

Abstract

A gradient indicating device has a housing 11 provided with a bearing surface 14 and with at least one light source 16 for producing a collimated light beam aligned parallel to the bearing surface 14, wherein the housing 11 comprises a carrier part 12 and a housing part 13, and wherein the bearing surface 14 as well as a receiver 15 for the light source 16 are formed in one piece by the carrier part 12. The carrier part 12 is preferably formed from aluminium or an aluminium or on aluminium alloy. The gradient indicating device according to the invention has the advantage that a handy and easy-to-assemble housing construction is guaranteed without impairing the accuracy of the device or its ability to withstand external influences such as temperature and impact forces.

Description

2348494 Gradient indicating device

Background art

The invention proceeds from a gradient indicating device according to the preamble of claim 1. A gradient indicating device is already known (DE 39 18 865 A I), which takes the form of a spirit level and is provided with a laser source, with the aid of which a light beam for levelling parallel to a bearing surface of the spirit level may be directed onto a remote surface. Although the construction of the housing of the spirit level is not described in detail in said publication, it is generally known for spirit levels to be manufactured from wood, plastic material or metalWhile housinp made of 0 wood or plastic material rapidly lose their dimensional accuracy and dimensional stability under rough building site conditions, housings made of metal are very expensive to manufacture and are moreover extremely heavy.

Advantages of the invention The gradient indicating device according to the invention having the features of claim 1 has the advantage that a handy, easy-to-assemble housing construction is guaranteed without impairing the accuracy of the device or its ability to withstand external influences such as temperature and impact forces Advantageous developments and improvements of the device accordin" to the t) invention are possible by virtue of the measures outlined in the dependent claims.

2 Drawings An embodiment of a gradient indicating device according to the invention is illustrated in the drawings and described in detail below. Figure 1 shows a longitudinal section through a gradient indicating device according to the invention, Figure 2 a perspective 0 view of the housing of the gradient indicating device of Figure 1, and Figure 3 a projection of a carrier part of the gradient indicating device Description of the embodiment

In Figure 1, 10 denotes a gradient indicating device having a housing 11, which comprises a carrier part 12 and a pot-shaped housing pail 13. The carrier part 12 is manufactured as a single-piece base plate by djecasting preferably frorn aluminium or an aluminium alloy. The carrier part 12 forms a flat bearing surface 14 of the gradient indicating device 10. The carrier part 12 moreover forms a receiver 15 for a light source 16. Furthermore, the carrier part 12 forms a locating surface 17, aligned parallel to the bearing surface 14, for a gradient indicator 18.

The gradient indicator 18 takes the form of a bubble level device having a polygonal, transparent body 19. The body 19 Is in said case supported by a lateral surface 20 against the locating surface 17 and is preferably glued to the latter. Formed in a known manner inside the body 19 is a cavity 21, which is filled by a liquid 22 embedded therein and by a bubble 23.

The light source 16 has a metal housing 24, in which a collimating lens 25 and an injection laser diode 26 are disposed. An outlet-side channel portion 27 of the metal housing 24 serves as the light outlet. Adjoining the channel portion 27, which is 0 1 3 formed by a hollow cylindrical extension 24a of the metal housing, is an outlet channel 18 and a further lens 29.

The pot-shaped housing part 13 is connected to the carrier part 12 by screws 30. The screw connection formed by the screws 30 in said case lies mid-way between a front end 3 1 and a rear end 32 of the device 10. In the region of the front end 3 1, the housing part 13 is additionally connected to the carrier part 12 by rneans of a detent connection 33, of which detent lugs 34 on the carrier part 12 are shown in Figure 3.

In the assembled state of the housing 11, corresponding detent hooks on the housing part 13 engage behind the detent lugs 34, thereby guaranteeing that the carrier part 12 and the housing part 13 are held securely together also in the region of the front end 31, Situated in the housing part 13 roughly mid-way between the front end 31 and the rear end 32 of the device 10 is an opening 35, into which a battery holder 36 is inserted.

The battery holder 36 takes the form of a drawer, into which batteries 37 are insertable and contacted with one another by means of contacts (not shown in detail). The battery holder 36 forms a cover 38 which, when the battery holder 36 is inserted into the opening 35, closes the opening 35 and terminates flush with an outside 39 of tile housing part 13. Injection-moulded onto the cover 38 is a detent hook 40, which engages with a projection 41 behind a lug 42 on the housing part 13. The screws 30 are in said case accessible from the opening 35, so that they are covered by the cover 38 when the battery holder 36 is inserted in the opening.

Situated in the rear part of the housing 11 is a setting screw 43, which is adjustable via a handle 44, by means of which the bearing surface 14 after being placed onto a measuring surface is to be aligned horizontally in accordance with the gradient indicator 18. With the aid of a release button 45 and a positioning mimic 46 the 4 setting screw 43 may be retracted into the housing 11 under the action of a compression spring 57.

Figure 2 shows a perspective view of the housing 11 of the device 10. The carrier part 12 with the downwardly directed bearing surface 14 is situated on an underside of the gradient indicating device 10. The housing part 13 is joined onto the carrier part 121.

Me opening 3 5 is covered by the cover 3 8. Situated laterally on the housing part 13 is a strip 47, which is disposed at the level of, and parallel to, a longitudinal axis 48 (Figure 1) of the light beam.

The handle 44 and the button 45 are situated in the region of the rear end 32 of the housing 11. In the region of the front end 3 1, wings 49 are supported one on either side of the housing 11 so as to be capable of swivelling outwards and serve as further bearing points in addition to the setting screw 43 for a three-point bearing for horizontally aligning the device 10. In order to be able to see the gradient indicator 18 a window 54 is cut out of the housing part 13.

Figure 3 shows a perspective view of the carrier part 12. The carrier part 12 is provided at its underside with the bearing surface 14 and has, parallel thereto, in one piece the locating surface 17 for the gradient indicator 18. Situated inside a locating block 50 for the light source 16 formed by the carrier part 12 is a through-opening 5 1, into which the metal housing 24 of the light source 16 (Figure 1) is insertable. The block 50 is provided with four bores 55, which extend at right angles to one another and in which aligning pins 56 are disposed. The aligning pins 56 support the metal housing 24, wherein they allow an alignment of the light beam relative to the bearing surface 14. The aligning pins 56 preferably take the form of threaded pins and, after alignment of the metal housing 24, are glued in the bores 55. By manufacturing the metal housing 24 from brass, the influence of temperature upon the accuracy of the 1 gradient indicating device may be reduced because brass has a similar thermal expansion to the aluminium used to manufacture the carrier part 12.

llic threaded bores 52 for the screws 30 are disposed mid-way between the front end 31 and the rear end 32 of the device 10. When only one detent connection 33 is provided at the front end 31 or rear end 32 of the device, the screw connection may alternatively be disposed at the, in each case, opposite end 3 1, 32. Situated in the region of the rear end 32 are a hole 53 for the setting screw 43 and a fastening point 54 for fastening the positioning mimic 46.

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Claims

1 Gradient indicating device having a housing (11), havl ing nj,-,, a hous' Z71 fixed bearing surface (14) and having at least one light source (16) for producing a collimated light beam aligned parallel to the bearing surface (14), characterized in that the housing (11) comprises a carrier part (12) made of metal and a housing part (13) made of plastic material, wherein the bearing surface (14) as well as a receiver (15) for the light source (16) are formed by the carrier part (12).

2. Device according to claim 1, characterized in that at least one gradient indicator (18) is provided, which takes the form of a bubble level having a polygonal transparent body (19), wherein the body (19) contains a cavity (2 1) with a liquid (22) embedded therein and with a bubble (23).

3. Device according, to claim 2, characterized in that the polygonal body (19) is supported by a lateral surface (20) against a locating surface (17), which is aligned parallel to the bearing surface (14) and formed by the carrier part ( 12).

4. Device according to claim 3, characterized in that the body (19) is glued to the locating surface (17).

5. Device according to one of the preceding claims, characterized in that the carrier part (12) is manufactured as a single-piece base plate preferably by diecasting.

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6. Device according to claim 5, characterized in that the carrier part (12) is made of aluminium or an aluminium alloy.

7. Device according to one of the preceding claims, characterized in that ZY a window (54) for the gradient indicator (18) is cut out of the housing part (13).

8. Device according to one of the preceding claims, characterized in that the carrier part (12) is detachably connected to the housing part (13) by means of at least one screw (30), which is covered by a housing cover C> (38).

9. Device according to claim 8, characterized in thal. in addition to the screw connection (30), at least one detent connection (33) is provided between carrier part (12) and housing part ( 13).

10. Device according to claim 9, characterized in that the detent connection C) (33) is disposed in the region of a front end (3 1) and/or a rear end (32), while the screw connection is provided in the region between the ends (3 1, 32) or in each case at the opposite end (3 1, 32) to the detent connection (33).

11 Device according to one of the preceding claims, characterized in that the light source (16) is formed by an iRlection laser diode (26), which cl is disposed in a through-opening (5 1) in a locating block (50) formed by the carrier part (12).

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12. Device according to claim 11, characterized in that the light source (16) is supported in the through-opening (5 1) by means of at least three, preferably four adjustable aligning pins (56).

13. Device according to claim 12, characterized in that the aligning pins (56) are disposed in bores (55) in the locating, block (50) and are preloaded towards a metal housing (24) of the light source (16).

14. Device according to claim 12 or 13, characterized in that the metal 10 housing (24) is of a sleeve-like design and is made of brass.

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15. A gradient indicating device substantially as herein described with reference to the accompanying drawings.

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