Technical field

The present invention relates to scales for weighing people, comprising: a system of levers for supporting a platform to which tne load to be weighed is applied, the lever system having principal levers and auxiliary levers which pivot on the same support and which act respectively on a device for displaying the load being weighed and on the principal levers for the support of the platform, - the principal and auxiliary levers being connected to one another by means of fastening means and counter-means. Background Art

In such scales, the platform is generally supported by a pair of principal levers which pivot on the support and which act on the display device detecting the load, and by a pair of auxiliary levers, each of which m turn pivots on the support and is connected to a corresponding principal lever for receiving the load applied to the platform and transferring it to the detecting device.

A known solution for connecting the auxiliary levers and the principal levers to one another uses a fastening ring slipped onto the principal lever m order to support one end of the corresponding lever.

However, during the assembly of the scales, this solution requires the pre-assembly of each pair of principal and auxiliary levers with the corresponding fastening ring. This operation is relatively laborious and unsuitable for automation.

The problem on which the present invention is based is to provide scales which are constructed and designed to overcome the disadvantages described with reference to the mentioned prior art. Disclosure of the Invention

This problem is solved by the invention by means of scales of the type described m the introduction, characterised m that the fastening means and counter- means are such that each of the auxiliary levers is connected directly to, by simply resting on, the corresponding principal lever.

It is thus possible to assemble the scales by mounting the principal levers on the support and by resting the auxiliary levers directly on the principal levers. Mounting is therefore effected directly from above without having to preassemble the set of levers (slipping the rings onto the principal levers and inserting one end of the auxiliary levers into the rings) . Brief Description of Drawings

The characteristics and advantages of the invention will become clear from the following detailed description of a preferred embodiment illustrated by way of non-limitmg example with ref-erence to the appended drawings m which:

Figure 1 is a perspective view of scales manufactured in accordance with the present invention; - Figure 2 is a perspective view of a detail of Figure

1; - Figure 3 is an exploded perspective view of the detail of Figure 1 during assembly;

Figure 4 is a perspective view, on an enlarged scale, of the detail indicated by arrow IV of Figure

3; and - Figure 5 is an enlarged sectional view along the line V-V of Figure 2.

Best Mode of Carrying out the Invention

In Figure 1, scales for weighing people are generally indicated 1 and comprise a support 2 having a polygonal base 2a which carries a system of levers 3 for supporting a platform 4 to which the load to be weighed is applied.

The lever system 3 comprises a pair of principal levers 5 diverging in a V-shape from the same plate- like body 6 which is preferably formed m one piece with the levers 5. The plate-like body 6 has an extension 7 m the direction of the bisector between the levers 5.

At each free end, in the region opposite the body 6, the principal levers 5 have a respective first V- shaped cutaway portion 8 which rests on a respective knife-edge formation 9 mounted on the support 2 and constituting the fulcrum for the corresponding principal lever. Starting from the free end, a second cutaway portion 10 opposite to the first is formed on each

lever 5 and a respective notch 11 is formed m a substantially central position.

A second knife-edge 12 rests m each of the second cutaway portions 10. Each second knife-edge 12 is omega-shapeα with two side arms 13a,b arranged to receive and support corresponding feet (not shown) of the platform 4.

The plate-like body 6 rests on a resiliently yielding support 14 which comprises a helical spring 15 and a spring-holder 16. The latter comprises a cup-shaped boα_v 16a which is guided on a pm 17 projecting from the base 2a of the support 2 and which has, externally, a thread onto which a sleeve 18 is screwed m an adjustable manner. The sleeve 18 has a flange m the form of a disc 19 which normally rests on the base 2a. The disc 19 is accessible from the outside of the scales m order to vary the screwing of the cup-shaped body 16a into the sleeve 18 and consequently to regulate the calibration of the scales 1.

The principal levers 5 act by way of the extension 7 on a device displaying the lead Demg weighed. This device, generally indicated 20, comprises, m addition to the support 14, a linkage 21 including a first and a second arm 21a,b which are at right-angles to one another, and is articulated centrally, by means of a pin 22, to two plates 23a,b projecting frcr the base 2a. The extension 7 is connected to, ry simply resting on, the free end of the arm 21a anc a rod 26 is connected to the free end of the arm 21b ry hinging.

A return spring indicated 26a acts between the support 2 and the rod 26.

A rack 27 is formed on the rod 26 and meshes with a pinion 28 which, n turn, is keyed onto a shaft 29 on which an indicator disc 30 graduated according to the value of the load being weighed is also secured.

The lever system 3 also comprises a pair of auxiliary levers which are each indicated 35.

Each lever 35 has, at one end, a first cutaway portion 8a resting on a respective knife-edge formation 9a of the support 2, and a second, opposite cutaway portion 10a. Respective knife-edges 12a, which have a structure identical to that of the knife- edges 12 and which are intended to bear corresponding feet of the platform 4, rest on the cutaway portions 10a.

A recess 36, at the base of which another knife- edge formation 37 is defined, is formed at the opposite end of each auxiliary lever 35. Each auxiliary lever 35 is connected to the corresponding principal lever 5 by directly resting the knife-edge formation 37 m the notch 11. Owing to this feature, the knife-edge formation 37 and the notch 11 are also indicated m the claims as fastening means and counter-means.

Thus, the assembly of the lever system 3 is achieved by mounting the principal levers 5 on the support 2 and resting the corresponding auxiliary lever 35 directly on each of tne principal levers 5. Mounting is therefore effected directly from above without reαuinng any pre-assembly of the lever system

3, for example without providing fastening elements interposed between principal and auxiliary levers.

It will also be appreciated that, in accordance with the invention, the principal levers 5 are in their turn mounted on the support 2 by resting directly on the respective knife-edge formations 9 and on the spring 15. Analogously, the knife-edges 12, 12a bear directly from above once the lever system 3 has been arranged on the support 2.