US2145515A - Proportionate scale - Google Patents

Description

Jan. 31, l939. F. KUCHER 2,145,515

PROPORT IONATE `SCALE Filed sept. 26, 1936 Patented Jan. 31, 1939 UNITED STATES PATENT OFFICE PROPORTION ATE SCALE Germany Application September 26, 1936, Serial No. 102,693 In Germany September 28, 1935 4 Claims.

My invention relates to improvements in weighing scales and more especially to an improved proportionate scale for determining the relative proportion or percentage of the constituents of mixtures which are to be prepared in frequent succession.

The new scale is designed more especially for application in the prepa-ration of amalgams by the dentist immediately prior to actual use in order to avoid a premature hardening of the amalgam.

The new scale belongs tothe type in which one of the pans or cups designed to receive the materials to be weighed is mounted on the beam for longitudinal displacement. I improve this type of scale by a novel design and arrangement of the parts constituting same which involves quite a number of advantages over similar scales hitherto available.

In the drawing aixed toy this specification and forming part thereof I have shown in a diagrammatic manner and by way of example an embodiment of my invention.

In the drawing Fig. 1 is a front elevation,

Fig. 2 a plan view and Fig. 3 a sectional side elevation on the line lll-HI in Fig. l.

Fig. 4 is a plan view, similar to the right hand 30 part of Fig. 2, showing the displaceable pan,

While Fig. 5 is a sectional side elevation thereof,

Fig. 6 being a cross section on the line VI-VI in Fig. 4.

Fig. 7 is a plan View of the carrier of the displaceable pan.

Referring to the drawing, I is a base plate and 2 a standard mounted thereon, 3 being the notch formed in the top of the standard, while 4 is the scale beam carrier, which is formed with a knife edge 1 seated at the bottom of the notch 3.

As shown more particularly in Fig. 3, two preferably cylindrical bars 5 and 6 extend through perforations in the scale beam carrier 4 and are iixed to it. On the left hand ends of the two bars 5 and 6 is fixed a pan carrier 8 carrying a pan 9.

On the right hand ends of the bars 5 and 6 is mounted for longitudinal displacement a movable pan carrier I0, the bars 5 and 6 extending through transversal borings formed in the carrier, which, as shown more particularly in Figs. 6 and 7, is formed with a central aperture 20, a conical depression I'I and a radial groove I6. A set screw I2 serves for xing the carrier in position on the bars. The carrier 8 is preferably designed in a similar manner.

The pans 9 are formed, as shown more particularly in Fig. 6, with conical depressions I3, a beaded circumferential portion I4 and a radial groove I5, the projecting bottom of which fits in the groove I6 of its carrier, while the depressed portion I3 nts in the conical depressed part I'l.

I8 and I9 are balancing weights, each being displaceably mounted on one of the bars 5 and S, set screws 2l serving to fix the weights in place.

The front bar 6 is formed with marks, notches or the like II, the purpose of which may be explained by an inscription provided on the base plate I and which serve to facilitate the adjusting of predetermined proportions. When the set screw I2 of the pan carrier I0 contacts with the bar 6, the passing in front of one of these notches I I will make itself felt to the operator, when the pan carrier IIl is displaced.

The balance weights I8 and I9 serve to counterbalance the empty pan carrier IIJ and pan 9 after each displacement.

The scale above described and shown in the drawing is particularly simple in construction and use and can be manufactured and sold at a low price, while at the same time being absolutely reliable and permitting the dentist to weigh the predetermined proportions of mercury and silver alloy required in each individual case with the greatest ease and rapidity.

If it is intended to weigh out for instance mercury and chips of a metal or of a mixture of metals to be amalgamated in a predetermined proportion, the right hand pan carrier I0 is placed in the position dened by the mark or notch I I, which corresponds to this proportion, and is fixed by means of the set screw I2. The scale with the two empty pans 9 on their respective carriers is then brought to balance by displacing the Weights I8 and I9 and fixing same by means of the set screws 2|. The scale is now ready for weighing out the substances in the predetermined proportion in as many batches as desired. An optional quantity of mercury is poured into the left hand pan, whereupon metal chips are placed into the right hand pan until the scale is balanced again. The quantities of the substances weighed out are inversely proportional to the'distances of the centers of the two pans from the knife edge l. If the substances shall be weighed out in a different proportion, the right hand pan carrier need merely be displaced correspondingly and then the same steps gone through anew.

I wish it to be understood that I do not desire to be limited to the exact details of construction shown and described for obvious modifications will occur to a person skilled in the art.

I claim:-

1. In a proportionate weighing scale, in combination, a pair of parallel bars forming the scale beam, a beam carrier fixed on these bars and formed with a knife edge, a pan carrier fixed near one end of the bars forming the scale beam, and another pan carrier being formed with bo r ings receiving said bars mounted near the other end of said 'bars for adjustment along the pair of bars forming the scale beam, pans removably seated in said carriers, the carriers being provided with a recess and the pans being shaped to conform with said recess, whereby the pans upon being inserted will assume an invariable position With respect to said carriers. and at least one balancing weight. mounted for adjust@- ment along at least one of said bars, whereby the rier with a similar groove, wherein the projecting radial bottom part of the groove is seated to prevent' rotationv of the pan relative to the carrier.

4. The scale of claim 1, in which a set screw extends through theadjustable pan carrier into contact with one of the bars constituting the scale beam, in combination with a mark on said bar adapted to coact with said set screw for indicating to the operator a predetermined position of theV pan carrier.

FRIDOLIN KUCHER.

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