Weighing apparatus including improved force-transmitting lever means

• US 4,497,386 A
• Filed: 12/27/1982
• Issued: 02/05/1985
• Est. Priority Date: 07/16/1982
• Status: Expired due to Term

• Current Assignee: Mettler Toledo GmbH
• Original Assignee: Mettler Instrumente AG (Mettler-Toledo International Inc.)
• Inventors: Meier, Eugen
• Primary Examiner(s): Goldberg, E. A.
• Assistant Examiner(s): Kampe, Fred L.
• Application Number:
  US06/453,103
• Time in Patent Office: 771 Days
• Field of Search: 177/154, 177/156, 177/184, 177/229, 177/255, 177/157, 177/158, 177/188
• US Class Current: 177/229
• CPC Class Codes: G01G 21/24 Guides or linkages for ensuring parallel motion of the weigh-pans
• CPC Class Codes: G01G 3/16 measuring variations of frequency of oscillations of the body

Abstract

Weighing apparatus of the short-stroke type is disclosed including a resilient parallel guidance arrangement (3) connecting a load-receiving member (2) for vertical movement relative to a console member (1), characterized by the provision of a pivotally movable lever (14) connected between the console and load-receiving members and including a resilient arm (18) for transmitting to the measuring device--for example, a vibratory string (23)--a force corresponding with the load applied to the load-receiving member. A stop device (20) is provided for limiting the extent of pivotal movement of the lever, the force introduced into the parallel guidance arrangement being only a fraction of the load to be measured, whereby the deleterious influences disturbing the measurement force are eliminated, whereby a relatively simple and inexpensive parallel guidance arrangement of less expensive materials may be achieved.

Claims

1. Weighing apparatus of the short-stroke type, comprising

(a) a console member (1);

(b) a load-receiving member (2);

(c) resilient parallel guide means (3) connecting said load-receiving member with said console member for vertical displacement relative thereto;

(d) short-travel movement measuring means (23) connected at one end with said console member;

(e) force transmitting lever means (14) connecting the other end of said measuring means with said load-receiving member, including

(1) a multi-arm lever (14) including a rigid first arm (19);

(2) pivot means (15) connecting said lever with said console for pivotal movement about a horizontal pivot axis (15a), said lever including a resilient second arm (18) connected with the other end of said measuring means; and

(3) means connecting said lever with said load receiving member, whereby vertical displacement of said load-receiving member is transmitted to said measuring means via said resilient second arm; and

(f) stop means (20) cooperating with said rigid first arm for limiting the extent of pivotal travel of said lever about its pivot axis.

2. Apparatus as defined in claim 1, wherein said short-travel movement measuring means comprises vibratory string means.

3. Apparatus as defined in claim 1, wherein said first and second arms are integral with said lever.

4. Apparatus as defined in claim 1, wherein said resilient second arm is formed of a material having a temperature coefficient that corresponds with that of said resilient parallel guide means.

5. Apparatus as defined in claim 3, wherein said lever comprises a die-cast body formed of an aluminum alloy.

6. Apparatus as defined in claim 1, wherein said pivot means comprises bendable resilient bearing means (15).

7. Apparatus as defined in claim 1, wherein said first (19) and second (18) arms are on the same side relative to the pivot axis of said lever, said arms being parallel and spaced relative to each other.

8. Apparatus as defined in claim 7, wherein said pivot means is arranged intermediate the ends of said lever, thereby defining a third arm (16) on the opposite side of the lever pivot axis from said first and second arms, said means connecting said lever with said load-receiving member including resilient bearing means (17) connected between said third arm and said load-receiving means.