GB2172576A - Measuring tape housing - Google Patents

Abstract

A measuring tape housing (1) accommodates a reel on which a measuring tape (58) (not shown) is wound and which can be withdrawn from the reel via an exit (4) in the housing (1). The housing has a flat face (14) (Figure 3, not shown) which forms the base of the housing and also has an opposite face (15) with raised portion (16) along one edge (17) of the housing. The raised portion has an inclined surface (19) that is readily visible to a user when taking measurements. The surface (19) mounts a display (22) and a keyboard (23, 24). The housing has a handle (10) movable with respect to the housing. The handle (10) is operatively connected to an arrangement (44, 45, 46, 47, 48, 49, 50) (Figure 9, not shown) for applying a predetermined tension to the tape (58) prior to taking a measurement. <IMAGE>

Description

SPECIFICATION Improvements in or relating to housings This invention relates to housings and has particular reference to housings for measuring tapes especially measuring tapes for use by surveyors and for use on building sites.

Measuring tapes are housed on a reel from which the tape is unwound when required for use. Frequently, the reels are accommodated in a housing and it has been proposed to locate in the housing means for sensing the unwinding of the tape and for indicating in digital form on a display the length of unwound tape. It has also been proposed to incorporate an electronic calculator to enable a user to perform calculations that may be associated with measurements taken with the measuring tape.

However, in some of the prior proposals, the display is not readily visible to a user and moreover, the calculator keyboard is not conveniently located for easy use.

It is one of the objects of the present invention to provide a housing in which the display and calculator keyboard are more readily visible and accessible than hitherto.

When taking long measurements, a correction to the observed reading has sometimes to be made to allow for the fact that the tape does not lie absolutely level but lies along a curve that is a catenary. The shape of the catenary depends upon the length of tape withdrawn from the reel and the tension applied to the tape. If the applied tension is not of the right value, the correction may be inaccurate.

It is another object of the present invention to overcome that problem.

In some conventional forms of surveyor's measuring tape, the reel carrying the measuring tape is rotatably supported in a frame that incorporates a carrying handle. The position of the handle is such that a user cannot easily withdraw tape from the reel nor readily observe the scale on the tape when taking a measurement.

Overcoming that disadvantage is another object of the present invention.

Thus, according to one aspect, the invention comprises a measuring tape housing accommodating a reel or other means on which the tape is wound and means for detecting and indicating the length of tape drawn off the reel, and in which the housing has a flat face forming a base for the housing and an opposite face contoured to provide a surface inclined with respect to the base at an angle such that the surface is readily visible to a user when taking a measurement, the indicating means and controls associated therewith being located on said surface.

Alternatively, the invention comprises a measuring tape housing providing accommodation for a reel on which the tape is wound and having a carrying handle, the handle or a part thereof being movable relatively to the housing and being operatively connected to means for applying tension to a length withdrawn from the housing.

Yet again, the invention comprises a measuring tape housing accommodating a reel or other means on which the tape is wound, the housing having a first wall with an exit from which the tape emerges from the housing and an opposite wall adjacent which is supported a carrying handle for the housing.

By way of example only, an embodiment of the invention will now be described in greater detail with reference to the accompanying drawings of which: Figure lisa perspective view of the embodiment, Figures 2-7 are, respectively, an elevation from one side, an elevation from the other side, a plan view, a front elevation, an underneath view and a rear elevation of the embodiment, Figure 8 is a perspective view of the embodiment with a movable component in an alternative position, Figure 9 is a diagrammatic view of part of another embodiment, Figure 10 is a front view of the lower portion of that part shown in Figure 9, and Figure 11 is a plan view of part of the interior of the housing.

The embodiment shown in the drawings is suitable for accommodating a surveyor's measuring tape which is wound on a reel (not shown) located within a housing 1. The reel is rotatably mounted within the housing from which the tape can be withdrawn from an exit 2 in the side wall 3 of the housing. The outer end of the tape is attached to a ring 4 by means of which the tape can be unwound from the reel. The ring 4 also prevents a user retracting the tape completely into the housing.

The reel is rotatable by means of a handle 5 shown in Figure 6 in a folded position and accommodated in a shallow recess 6 in the lower face of the housing 1. The handle 5 is used to rewind the measuring tape back on the reel.

The housing itself is of generally rectangular form - being approximately square - when seen in plan as in Figure 4 and comprises a moulded container of a suitable plastics material. In general, a clam-shell construction may be used for the main body of the housing, the two halves of the clam shell meeting along a junction line indicated at 7.

The housing is contoured along side wall 8 opposite side wall 3 to provide a recess 9 bridged by a handle 10 mounted for movement relatively to the housing 1 for reasons that will be explained below.

The recess 9 enables a user to grip the handle 10 easily. The handle 10may be pivotally mounted on the housing 1 about a pivotal axis indicated at 11 so thatthe handle can be pivoted away from and back to the housing. Pivotal movement of the handle occurs against the action of resilient means, for example a spring, that biases the handle into the position shown in the drawing. Alternatively, the handle may be slidably mounted upon the housing and movable away from and back to the housing.

The extent of movement of the handle relatively to the housing is indicated buy a scale 12 movable relatively to a pointer 13.

Except for the recess 6, the lower face 14 of the housing is planar and forms a steady base on which the housing 1 can be placed when not in use for taking measurements.

The upperface 15 of the housing has a raised portion 16 along one edge 17. The portion has a forward-facing, downwardly- and outwardly-sloping surface 18. The raised portion 16 also has a rearward-facing, downwardly- and outwardly-sloping surface 19. As can be seen from the drawings, the surfaces 18 and 19 meet along a ridge 20 that is parallel to the edge 17. Along the edge, the clam shell halves are contoured to provide a backwards sloping surface 21 that merges in an aesthetically attractive manner with the contour of the portion 16.

Contained in the housing 1 in the portion 16 is part of the electronic circuitry including a microcomputer used to detect and measure movement of the tape into and out of the housing. Such movement is indicated in digital manner on a display indicated by block 22 located in surface 18. Associated with the circuitry are keys indicated as blocks 23 and 24that enable a user to select whether measurements are made in Imperial or Metric units, the selection then being indicated on the display. Further keys indicated as blocks 25 and 26 enable a user to enter corrections to an indicated measurementforthe catenary length, and ambienttemperature. Afurther key indicated as block 27 enables connection to be made to an external power supply.

Also located on the surface 18 are keys, indicated as blocks 28, for entering numerical values 0-9 into the computer calculator housed in portions 16.

Further keys indicated by blocks 29 control the usual arithmetic functions of the computer and enable a user to take into use the display 22 for calculation purposes. Other functions provided by the keys represented as blocks 29 include the ability to store one or more measurements, the ability to carry out trigonometrical calculations using stored measurements or measurements separately entered and the ability to print out the stages and results of a calculation on a small matrix printer also located, together with a roll of paper, in the portion 16.

Operation of the printer can be observed through a window 30 beneath which the printer is located. The window is slotted as at 31 to provide an exit for paper from the printer, one edge of the slot being serrated to enable a user easily to tear off a length of paper. The block 29 of keys also inicudes a key for "holding" a displayed length and another key for adding on to a displayed length anotherfibed length representing the length of the housing between the exit 2 and the handle 10. Ingress of moisture and other deleterious substances into the housing via the key 1 is prevented by the use of membrane keyboard.

The inclination of the surface 18 is so selected that when the housing is held with the handle 10 vertical the position in which tape is withdrawn for measurement purposes -the display 22 can easily be seen by the user and is not obscured by the user's hand which is holding the handle 10. The inclination is also such that when the housing is laid on its base formed by the lower face 14, the display and all the keys are easily seen and the keys readily operated by the user.

Edge 32 of the housing has a flap 33 that is detachable from the housing to give access to a wiper head inside the housing and through which the tape passes after entry into the housing and which serves to "wipe" from the surface of the tape any removable contamination, for example earth and mud, thereon before that surface passes beneath a tape movement sensing head (not shown) that is connected to the electronic circuitry referred to above.

Alternatively, the flap 33 may be pivotally attached at one end to the housing 1 and simply swung away from the latter to give the access just mentioned.

As can be seen from certain of the drawings, particularly Figure 4, the flap 33 has an end portion 34 that projects forwardly from the side wall 3. The upper side of portion 34 is marked with an arrow head 35 that points away from a small stud 36 also projecting forwardly from side wall 3 but at that end thereof remote from portion 34. The function of the arrow head 35 and stud 36 are described above.

Located in edge 37 of the housing adjacent the lower end of the handle 10 is the outer end 38 of an internal socket that is internally screw-threaded. The function of the socket will be dealt with below.

If desired, a spirit level or other form of level indicator may be mounted upon the housing in a position in which it can readily be observed by a user. Such a position may be on side wall 3 adjacent the stud 36.

In use, a user holds the housing in an upright position by means of the handle 10 and the measuring tape is pulled out by means of the ring 4. The orientation of the housing in the upright position can be checked by means of the spirit level or by means of a plumb line fixed to the stud 33 and aligned with the arrow head 32. At some appropriate time, the display has been set to indicate measurement in the desired units and the extended length of the tape is then indicated on the display as the tape is withdrawn from the housing.

The user is able readily to observe the display 22 because of the inclination of the surface 18 in which the display is mounted and because the handle 10 is so positioned that neither the handle nor the user's hand holding the handle or his arm obscure the display.

Before a particular measurement is taken, the user tensions the tape by pulling gently on the handle 10 while the ring 4 is held securely against movement.

Movement of the handle 10 resulting from that pull moves the pointer 13 relatively to the scale 12 and when a particular position on the scale is reached the key represented by block 25 is depressed and the appropriate correction to the displayed length is effected automatically.

If it is thought necessry to correct the displayed reading for the effect of ambient temperature key 26 is depressed and the value of the ambient temperature entered using the appropriate keys of block 28.

A correction is then automatically made to the displayed value.

Conveniently, the housing may provide accommodation for a thermometer to enable a user to measure the ambient temperature. A suitable thermometer of robust characteristics is the known liquid crystal thermometer that indicates tempera ture by colour changes of discrete temperature sensitive areas.

A liquid crystal thermometer may be mounted at any suitable location in or on the housing 1.

Preferably, however, and as shown in Figure 8, the handle 10 has a lift-up cover 39 pivotally secured at one end to the handle. Mounted upon the inside face of the cover 39 is a liquid crystal thermometer indicated by block 40.

Before taking a measurement, a user raises the cover 39, and, after a short interval of time to allow the thermometer to adjust to the ambient temperature, a reading is taken. The adjustment time required isrelatively short because handle 10 is hollow and a window 41 in the cover 39 permits entry of air into the handle.

If desired, the user, instead of holding the housing in his hand, may attach a support to the housing using the socket referred to above. The support may be a tripod or may be a single leg support thrust into the ground.

Figure 9 shows part of another embodiment with the front of the housing removed. The embodiment of Figure 9 has a housing one part 40 of which has an upper lateral extension 41 to which the handle 10 is pivotally attached as at 42. The handle is accommodated in the recess 9 in the housing between the upper extension 41 and a lower lateral extension 43 of the housing part 40.

Attached to the lower end of the handle 10 is one end of a link 44. The other end of the link is pivotally secured to a carrier 45 carrying two rollers 46,47 each rotatable in the carrier about axis 48, 49 respectively. The carrier has an extension 50 slidably mounted in a guideway 51. Movement of the carrier 45 away from the guideway 51 due to anti-clockwise rotation of the handle 10 occurs against the action of a helical spring 52 secured between the end of the guideway 51 and the inner end of the extension 50.

Also mounted upon the carrier 45 by means of a pin 53 is a pointer 54 that lies outside the housing and is movable with the carrier 45 over a scale 55 on the other part 56 of the housing. That part 56 is slotted as at 57, the pin 53 passing through the slot 57.

The measuring tape 58 passes round rollers 46 and 47 as shown in Figure 9 before being wound on to the reel 59.

In use, a user having reeled out a sufficient length of measuring tape to give an approximate indication of a particular measurement, then pulls gently on the handle 10 causing the latter to pivot about pivotal axis 42. This causes the carrier 56 to move away from the guideway 51 against the action of spring 52 and at the same time to tension the length of measuring tape so taking up the catenary. When the movement of the pointer 54 relatively to the scale indicates that the correct tension is applied, the length of tape is read-off from the display.

In an alternative embodiment only a part of the handle 10 is movable relatively to the housing against the resilient bias, that part being operatively connected to the arrangement for tensioning the tape.

It will be appreciated that the handle or the part thereof may be slidably mounted in or on the housing and movable relatively thereto against the resilient bias. Alternatively, the handle 10 may be fixed relatively to the housing and tensioning achieved in some other way.

Figure 11 which shows part of the interior of the housing reveals one such other way. Tape 58 entering the housing via exit 2 passes through the wiper head 60, beneath the electronic sensing head 61 and then over a roller 62 rotatably mounted upon a spring-loaded support 63. From the roller 62, the tape 58 winds on to the reel 59.

The support 62 extends from a mounting 64 fixed relatively to the housing 1 and is movable towards and away from the mounting 64 according to the tension in the tape 58. The support is linked to an indicator either visual or audio which indicates when that movement of the support has taken place which corresponds to the desired tension in the tape.

In this case, the user simply pulls gently on the handle 1 to tension the tape, the ring 4 being held against movement. When the indicator indicates application of the required tension, the user simply presses the key represented by block 25 and the appropriate correction is made to the displayed tape length.

Figure 11 also reveals the location of some other components within the housing 1.

Also shown are the paper roll 65 that feeds the printer 66, the cassette 67 of the printer ribbon, the connector 68 electrically interconnecting the printer and the microcomputer, and a further connector 69 interconnecting the keyboard and the microcomputer. Batteries 70 that energise the electron circuit and its associated components are also shown in Figure 11.

Further details of the electronic controls and circuits are to be found in U.K. Patent Appiication No. (Case II), the contents of which are hereby incorporated into this present Application.

As has been described above, the microcomputer can be used to carry out calculations involving measurements taken. Additionally, the microcomputer can be programmed to carry out certain calculations automatically on depression of an appropriate key. That capability is particularly useful in building operations when a building site is being surveyed and laid out preparatory to initiating the building operation.

For example, the marking out of foundations for a building can be carried out using the tape measure and a conventional surveyor'stheodolite. The theodolite is accurately located at a first corner of the site. A first side is then measured from the first corner and its direction indicated thus giving the exact location of the second corner which is then accurately marked. The thoedolite is then rotated through 90 and the direction of the second side thereby obtained. The lengths of the two sides are then inputted to the calculator and by pressing the appropriate key the diagonal length of the rightangled triangle based on the first and second sides is then displayed.

The diagonal length is then measured from the second corner to meet the third side thus identifying the position of the third corner.

The direction of the third side is identified using the theodolite at the third corner and the diagonal length used to identify the location of the fourth corner. That location will be exact and it is not necessary to measure the distance between the third and fourth corners.

It may not be possible, in some cases, to use the tape for making measurements. To cater for such cases, the housing 1 may also accommodate an uitra-sonic device or a microwave device for making such measurements. Outputs derived from such devices will be processed by the microcomputer referred to above for display in the same manner as measurement using the tape.

It is to be understood that the above described embodiments incorporate several features which can be used separately. Thus, the housing may simply accommodate a reel or other means on which the tape is wound, the tape emerging from an exit in one wall of the housing while a carrying handle is located adjacent an opposite wall. Such an arrangement enables a user to hold the housing more easily whilst taking a measurement.

Furthermore, in such a case, the handle or a part thereof may or may not be movable relatively to the housing for the purpose of tensioning a length of tape withdrawn from the reel and the housing.

Claims (33)

1. A measuring tape housing accommodating a reel or other means on which the tape is wound and means for detecting and indicating the length of tape drawn off the reel, and in which the housing has a flat face forming a base for the housing and an opposite face contoured to provide a surface inclined with respect to the base at an angle such that the surface is readily visible to a user when taking a measurement, the indicating means and controls associated therewith being located on said surface.

2. A housing as claimed in claim 1 in which the surface extends upwardly and away from an edge of the opposite face.

3. A housng as claimed in claim 2 in which the surface extends substantially along the entire length of the edge.

4. A housing as claimed in any one of the preceding claims and having an exit for the tape located in a wall of the housing at one end of the inclined surface.

5. A housing as claimed in claim 4when appended to claim 2 or 3 in which the orientation of the reel or other means within the housing is such that the tape emerges from the exit in a direction generally parallel to the edge.

6. A housing as claimed in claim 4 or 5 and further comprising a carrying handle located at that end of the inclined surface opposite to said one end.

7. A housing as claimed in claim 6 in which the handle or a part thereof is movable relatively to the housing, the handle or the part thereof being operatively connected to means for applying tension to a length of tape withdrawn from the reel.

8. A housing as claimed in claim 7 in which means are provided for indicating the extent of movement of the handle or the part thereof relatively to the handle.

9. A housing as claimed in claim 7 or 8 in which the handle or the part thereof is pivotally attached to the housing.

10. A housing as claimed in claim 7 or 8 in which the handle or the part thereof is slidably attached to the housing.

11. A housing as claimed in any one of the preceding claims in which the surface is part of a portion of the opposite face that is raised relatively to the remainder of said face.

12. A housing as claimed in claim 11 in which the raised portion comprises a second surface inclined downwardly towards the remainder of said face.

13. A housing as claimed in claim 12 in which there is a transparent window or an aperture in the second surface.

14. A measuring tape housing providing accommodation for a reel on which a measuring tape is wound, and in which means are provided for indicating when a predetermined tension has been applied to a length of tape withdrawn from the reel.

15. A housing as claimed in claim 14 in which the means comprises a roller that is movable as tension is applied to the tape.

16. A housing as claimed in claim 15 in which the roller is movable against resilient means.

17. A housing as claimed in claim 14, 15 or 16 in which the indicating means provides an audible or visible indication when the predetermined tension has been applied.

18. A measuring tape housing providing accommodation for a reel on which the tape is wound and having a carrying handle, the handle or a part thereof being movable relatively to the housing and being operatively connected to means for applying tension to a length of tape withdrawn from the housing.

19. A housing as claimed in claim 18 in which means are provided for indicating the extent of movement of the handle or the part thereof relatively to the handle.

20. A housing as claimed in claim 18 or 19 in which the handle or the part thereof is pivotally attached to the housing.

21. A housing as claimed in claim 18 or 19 in which the handle or the part thereof is slidably attached to the housing.

22. A measuring tape housing accommodating a reel or other means on which the tape is wound, the housing having afirstwall with an exitfrom which the tape emerges from the housing and an opposite wall adjacent which is supported a carrying handle for the housing.

23. A housing as claimed in claim 22 in which the first and opposite walls are separated by the body of the housing in which the reel is accommodated.

24. A housing as claimed in claim 22 to 23 in which the handle or a part thereof is movable relatively to the housing, the handle or the part thereof being operatively connected to means for applying tension to a length of tape withdrawn from the reel.

25. A housing as claimed in claim 24 in which means are provided for indicating the extent of movement of the handle or the part thereof relatively to the handle.

26. A housing as claimed in claim 24 or 25 in which the handle or the part thereof is pivotally attached to the housing.

27. A housing as claimed in claim 24 or 25 in which the handle or the part thereof is slidably attached to the housing.

28. A housing as claimed in any one of the preceding claims in which a part of the housing is adapted to provide access to the interior thereof.

29. A housing as claimed in claim 28 in which the part comprises a flap pivotally attached to the housing.

30. A measuring tape housing as claimed in any one of the preceding claims in which means are provided for attaching a plumb line to the housing in such manner as to enable the housing to be orientated in a vertical plane.

31. A housing as claimed in any one of the preceding claims in which means are provided for mounting the housing on a supporting structure.

32. A housing as claimed in claim 31 in which the means comprise a socket.

33. A measuring tape housing substantially as described with reference to and as illustrated by the accompanying drawings.