GB2135969A

GB2135969A - A tape measure

Info

Publication number: GB2135969A
Application number: GB08404109A
Authority: GB
Inventors: Syunya Takeda
Original assignee: Sekisui Jushi Corp
Current assignee: Sekisui Jushi Corp
Priority date: 1983-02-16
Filing date: 1984-02-16
Publication date: 1984-09-12
Also published as: GB2135969B; GB8404109D0; FR2541446A1; CA1254033A; DE3404629A1; FR2541446B1; DE3404629C2

Abstract

A rewindable tape measure including an outer case 1, a reel 3 for a tape rotatably supported in the case, a handle 6 external of the case to effect rotation of the reel to rewind the measuring tape, by means of a first, externally toothed, gear 41 coaxial and fixed with the reel and a second internally toothed gear 23 secured to a shaft of the handle and surrounding the first gear, the first and second gears being engaged with each other. <IMAGE>

Description

SPECIFICATION A tape measure The invention relates to a tape measure, and more particularly to a tape measure which can rewind quickly.

Known tape measures are made by rotatably mounting a reel in an outer case and winding a measuring tape around the reel. Some tape measures have a coil spring provided in the interior of the reel so that the measuring tape can be automatically rewound around the reel by the restoring force of the spring. This type of tape measure is generally used when the tape has a comparatively short length, in particular less than 10 m. Since it is difficult to rewind the tape by the restoring force of a spring when the tape exceeds a length of from 10 m, say up to 100 m, longer tape measures have been made so that the measuring tape can be rewound by manually rotating a handle. Tape measures of this kind are made by rotatably placing a reel in a case to enable winding the tape around the reel, and also by providing a side of the case with a handle for rotating the reel.

According to the present invention,there is provided a rewindable tape measure including an outer case, a reel for a tape rotatably supported in the case, a handle external of the case to rotate the reel to rewind the measuring tape, a first, externally toothed, gear coaxial and fixed with the reel and a second internally toothed gear secured to a shaft of the handle and surrounding the first gear, the first and second gears being engaged with each other.

The invention will be more clearly understood from the following description which is given by way of example only with reference to the accompanying drawings, in which: Figure 1 is a front view of a first tape measure of the invention, Figure 2 is a sectional view taken along line ll-ll in Figure 1, Figure 3 is a front view, partly cut away, of the reel shown in Figure 1, Figure 4 is a front view of a second tape measure of the invention, Figure 5 is a front view of the tape measure of Figure 4, with a half side cut away, Figure 6 is a front view of the tape measure of Figure 4 with the reel removed and Figure 7 is a perspective, partially exploded view of the tape measure of Figure 4 with the shaft supporting plate removed.

The tape measure of Figures 1 to 3 has a case 1 with a grip 17 at an upper portion thereof and a stake point 18 at a lower portion thereof. Case 1 is also provided with winder 2 including a handle 6 and a shaft 21 integrallyformedwith handle 6.

The winder 2 is in a protuding cover portion 11 of the case 1 and is situated between, and supported by, the wall of protruding portion 11 and a supporting plate 12 covering the opening to protuding portion 11 from the rest of the case. Supporting portion 24 of the handle 6 is fitted and rotatably supported in an aperture 14 of the protruding cover porton 11. Thus, the winder 2 can be rotated in case 1 when handle 6 is turned. The interior of the winder 2 is recessed at 22 except for the shaft 21, and internal gear teeth are formed on the inner periphery of the recessed portion.

Atape reel 3 is in the case 1 and has a measuring tape 5 windable, or wound, therearound. The reel 3, as shown in Figures 2 and 3, is provided with flanges 32 of large diameter at both ends of a hub 31, which is provided with a ring 33 for fastening the end of the measuring tape 5 and a groove 34 for receiving the ring 33 when the ring 33 is laid down. Each of the flanges 32 is provided with a plurality of apertures distributed in its surface. The apertures allow removal of sand, dirt and water from the measuring tape when the tape measure is washed. Each of the flanges 32 is further provided with an aperture 37 which is for use when either securing or removing the end of the measuring tape 5 to or from ring 33.

A shaft 4 supports the reel and is inserted into a center hole 36 of reel 3. One end of the shaft 4 is supported by an aperture 15 in the supporting plate 12, and the other end of shaft 4 extends into an aperture 16 in the case 1. Center hole 36 is square in cross section and shaft 4 is also generally square so that reel 3 is prevented from idling on the shaft 4.

Shaft 4 extends through the supporting plate 12 to the winder 2, and carries an externally toothed gear engaged with the internal gear 23. Thus, shaft 4 is rotatably received in the case and is provided with the external gear 41 located between winder 2 and supporting plate 12.

The measuring tape 5 is made for instance of a band steel, or a fibre-reinforced synthetic resin band, and has a length of 50m to 100 m, for example.

In a particular exemplary embodiment, the winder 2 has an internal gear 23 of an inside diameter of 45mm and shaft 4 has external gear 41 of an outside diameter of 12mm. The rotation ratio of the internal gear 23 to the external gear 41 is 1 to 3.75. Drum 31 in reel 3 has an outside diameter of 63mm, which holds a ring 33, and a measuring tape of steel having 50 m in length is secured to ring 33. When the handle 6 is rotated, all of the steel tape measure can be readily rewound. Forty rotations of the handle are sufficient to rewind all of the measuring tape.

Further, since the measuring tape can be rewound in the same direction as the handle rotating direction, no strange feeling is experienced during rewinding of the measuring tape and the measuring tape can be rewound smoothly. In contrast, where the reel is directly connected with and rotated by the handle to rewind the measuring tape of 50 m length, one hundred and fifty rotations of the handle are required.

The second embodiment shown in Figures 4 to 7 has a case 10, a reel 30 for winding a measuring tape 50, a winder 20, and a shaft 40 for supporting and rotating reel 30. The case 10 is formed by opposed, screwed together, plates of which one is a mirror image of the other. An opening 19 through the two plates is formed at a position opposite to an exit point of the measuring tape from the case 10. The outer edge of the opening 19 forms a grip 17', which is convenient for the hand and can be curved or, as shown, can be shaped to have three sides such as three sides of a rectangular octagon centred on the shaft 40 supporting the reel 30, with the pairs of sides making angles with each other of 135". Stake point 18' is formed on the opposite side from grip 17'.

Winder 20 is connected with a handle 60 outside the case. The base of handle 60 is fitted in an aperture in case 10 and is rotatable in case 10. A metal ring is secured to case 10 between the aperture in case 10 and the base of handle 60 for assisting in smooth rotation of handle 60. Winder 20 is provided with an internal gear 23 and shaft 21, both of which are integrally formed with winder 20.

Winder 20 is made of a hard thermoplastic synthetic resin, for example, polyacetal.

Shaft 40 extends within the internal gear 23 and has an external gear 41 at one end. A middle portion 42 of the shaft 40 is fitted in aperture 14 at one end, with one end of shaft 21 being simultaneously fitted in aperture 13 in supporting plate 12. Both shafts 40 and 21 are rotatably supported by supporting plate 12, resulting in gear 41 engaging with internal gear 23. Shaft 40 and supporting plate 12 are preferably made of hard thermoplastic synthetic resin such as polyacetal.

A plate spring 80 is provided in the vicinity of the place at which external gear 41 contacts the internal gear 23. Plate spring 80 urges internal gear 23 against external gear 41,so as as to give secure, smooth and quiet running.

A metal ring 70 is interposed between the middle portion 42 of shaft 40 and the aperture 14 of supporting plate 12, so that the shaft 40 rotates smoothly.

The shaft 40 has a square cross section in the portion 43 which is just outside the supporting plate 12. Reel 30 is placed on the portion 43. A central aperture 36 in the reel 30 is made square, so that the reel 30 can just be fitted in the portion 43.

Reel 30 has two flanges 32, each having perforations 35. In the other respects, reel 30 is the same as that shown in Figures 1 to 3.

With both embodiments, when the handle mounted on the winder is rotated, the reel is rotated in a higher speed, in proportion to the ratio of the internal gear to the external gear, so that the measuring tape can be rewound at a high speed.

Consequently, the tape measure has the advantage that an elongate measuring tape having a length of more than 10 m, particularly 50 mto 100 m can be rewound quickly.

Further, the winder is provided with the internal gear, and therefore, the winder can be rotated in the same direction as the reel, so that the tape measure can be rewound in the same direction as the handle rotating direction, hence the measuring tape can be smoothly rewound.

Furthermore, the winder shaft can be close to the shaft for the reel, so that the tape measure as a whole is stable during rewinding. The external gear can be placed in a recessed portion ofthewinder, and the case can be of small volume so that the tape measure is convenient to carry.

The winder and the shaft can be made of a hard thermoplastic resin, so as to be easily manufactured.

They can also be quiet during rotation, particularly when the metal ring is provided at the contacting portion thereof, which also leads to reduced wear.

A plate spring can be provided in the portion where the external gear contacts the internal gear, so as to press the gears together, which leads to quieter operation.

Claims

1. A rewindable tape measure including an outer case, a reel for a tape rotatably supported in the case, a handle external of the case to rotate the reel to rewind the measuring tape, a first, externally toothed, gear coaxial and fixed with the reel and a second internally toothed gear secured to a shaft of the handle and surrounding the first gear, the first and second gears being engaged with each other.

2. A rewindable tape measure according to claim 1 including a spring contacting an outer face of the second gear to press it into contact with the first gear.

3. A rewindable tape measure according to claim 1 or 2 wherein the shaft supporting the reel and the first external gear are formed integrally of a hard synthetic resin.

4. A rewindable tape measure according to claim 1,2 or 3 wherein a shaft for the reel is supported by a supporting plate made of a hard synthetic resin, with a metal ring interposed between the shaft and the supporting plate.

5. A rewindable tape measure according to claim 1, 2, 3 or 4 wherein the case is provided with a carrying grip at a portion opposite to an exit point of the measuring tape from the case.

6. A rewindable tape measure according to claim 5 wherein the grip is formed in a shape having three sides of a regular octagon centred on the shaft supporting the reel and includes at least three straight portions of which adjacent ones are at an angle of 135 to one another.

7. A rewindable tape measure constructed and arranged substantially as hereinbefore described with reference to and as illustrated in Figures 1 to 3 and Figures 4 to 7 of the accompanying drawings.