PLATFORM SCALE

• US 3,835,946 A
• Filed: 09/04/1973
• Issued: 09/17/1974
• Est. Priority Date: 09/29/1972
• Status: Expired due to Term

• Current Assignee: Mettler-Toledo AG IM Langacher Greifensee Switzerland
• Original Assignee: Erhard Mettler
• Inventors: Mettler, Erhard
• Primary Examiner(s): Miller, Jr., George H.
• Application Number:
  US05/394,085
• Time in Patent Office: 378 Days
• Field of Search: 177/210,211,256-259
• US Class Current: 177/256
• CPC Class Codes: G01G 1/24 Platform-type scales, i.e. having the pans carried above the beam

Abstract

Weighing apparatus of the platform scale type, characterized by the provision of load lever means including a pair of parallel load levers of unequal lengths for transmitting the vertical movement of the platform to weighing means mounted on one side thereof. Each load lever is connected at a first end with the frame of the apparatus, the other ends of the levers being connected with the weighing means. The load force of the platform is applied to an intermediate point on each of the levers adjacent their first ends, the ratio of the distance between said intermediate point and said first lever end to the distance between the intermediate point and the other lever end being the same for each lever. Preferably the said other ends of the load levers are connected with the weighing means by means including a pair of knife edges having a common horizontal line normal to the lever axes, the first ends of the levers extending under the platform means.

Claims

1. Weighing apparatus of the platform scale type, comprising a. a frame (F);

b. load lever means comprising a pair of generally horizontal load levers (8,

     9) of unequal length, said load levers being arranged with first ends (12,

     13) thereof adjacent each other;

c. first connecting means (10) pivotally connecting first portions of each of said load levers remote from said first ends with said frame for pivotal movement about pivot axes normal to the longitudinal axes of said load levers, respectively;

d. weighing means (18) connected with said frame, said weighing means including a transducer having a short operating stroke;

e. second connecting means (14, 15,

     16) connecting said load lever first ends directly with the transducer of said weighing means;

f. a platform (5); and

g. third connecting means (6) connecting said platform with second portions of each of said load levers remote from said first lever ends and spaced from said first portions, the ratio of the distance between said first and third connecting means and the distance between said second and third connecting means being the same for each of said load levers.

2. Apparatus as defined in claim 1, wherein said levers are parallel and are arranged on the same side relative to said weighing means.

3. Apparatus as defined in claim 1, wherein said transducer means comprises an electromechanical transducer.

4. Apparatus as defined in claim 1, wherein the ratio of the distance between the first anD third connecting means to the distance between the second and third connecting means for each lever is 1:

9.

5. Apparatus as defined in claim 1, wherein said second connecting means include a generally C-shaped connecting member (16) for applying the downward load force of said other lever ends to the transducer means of said weighing means.

6. Apparatus as defined in claim 1, wherein said second connecting means include knife-edge carriers (14, 14'"'"''"'"') connected with said first ends of said load levers, respectively, said knife edges being contained in a common horizontal line that extends parallel with the load lever pivot axes defined by said first connecting means, respectively.

7. Apparatus as defined in claim 6, wherein each of said load levers is bifurcated at the end thereof remote from said first end to define a pair of arm portions, said first connecting means comprising a plurality of knife-edge bearing means pivotally connecting the bifurcated arm portions of said load levers with said frame, respectively, the knife-edge bearing means associated with each lever lying in a common horizontal line.

8. Apparatus as defined in claim 7, wherein said third connecting means (6) comprise a plurality of knife-edge bearing means for connecting said bridge means with each of said bifurcated arm portions of said load levers, respectively, the knife-edge bearing means associated with each of the load levers being contained in a common horizontal line parallel with the load lever pivot axes.

9. Weighing apparatus of the platform scale type, comprising a. a frame (F);

b. load lever means comprising a pair of generally horizontal load levers (8,

     9) of unequal length, said load levers being arranged with first ends (12,

     13) thereof adjacent each other;

c. first connecting means (10) pivotally connecting first portions of each of said load levers remote from said first ends with said frame for pivotal movement about pivot axes normal to the longitudinal axes of said load levers, respectively;

d. weighing means (18) connected with said frame, said weighing means including a transducer having a short operating stroke;

e. second connecting means connecting said load lever first ends with the transducer of said weighing means, said second connecting means comprising a linkage assembly including a plurality of links (19,

     20) connected to provide an increased weighing capacity;

f. a platform (5); and

g. third connecting means (6) connecting said platform with second portions of each of said load levers remote from said first lever ends and spaced from said first portions, the ratio of the distance between said first and third connecting means and the distance between said second and third connecting means being the same for each of said load levers.