Compact direct measuring system

Patent metadata

Field	Value
Publication number	US-11221250-B2
Application number	US-202016800017-A
Country	US
Kind code	B2
Filing date	Feb 25, 2020
Priority date	Mar 11, 2019
Publication date	Jan 11, 2022
Grant date	Jan 11, 2022

Abstract

An electromagnetic force-compensation direct measuring system (100) has a load receiver (101), which is connected to a force-compensation device (120) via a power-transmission linkage. The system has a multipart parallel guide mechanism, which has at least two parallel-guiding members (131, 132) spaced apart by the power-transmission linkage. The force-compensation device has at least one permanent magnet (121) and a coil (122) electrically connected to a controllable electrical circuit. At least one parallel-guiding member is electrically integrated in the controllable electrical circuit. The power-transmission linkage is designed as a single-part coil body (110) such that the coil is arranged on the coil body between the parallel-guiding members and is electrically connected to the controllable electrical circuit.

First claim

What is claimed is:

1. An electromagnetic force-compensation direct measuring system comprising:
a force compensation device having at least one permanent magnet and a coil electrically connected to a controllable electrical circuit;

a load receiver, comprising a multipart parallel guide mechanism, which has at least two parallel-guiding members, with at least one of the parallel-guiding members electrically integrated in the controllable electrical circuit; and
a power-transmission linkage which connects the load receiver to the force-compensation device and which spaces the at least two parallel-guiding members apart, the power-transmission linkage being electrically connected to the controllable electrical circuit and designed as a single-part coil body with the coil arranged on the coil body between the parallel-guiding members.

2. The direct measuring system according to claim 1 , wherein the coil body consists of a nonconductive material.

3. The direct measuring system according to claim 2 , wherein:
the coil body has at least two conductor tracks electrically isolated from one another, a first of the conductor tracks leading to the coil and a second of the conductor tracks leading away from the coil.

4. The direct measuring system according to claim 3 , wherein:
the material of the coil body is at least partially a thermoplastic doped with a nonconductive laser-activatable metal connection as the plastic additive, on said thermoplastic the electrical conductor tracks are activated by a laser.

5. The direct measuring system according to claim 1 , wherein:
the force-compensation device comprises:
at least one permanent magnet,
at least one pole shoe, and
a device housing, such that the permanent magnet, the pole shoe, and the device housing are durably connected to one another, and

the coil body has a shaft region, a winding region for the coil that extends concentrically with respect to the shaft region, and a bar that connects the shaft region and the winding region, such that the device housing at the same time forms the housing of the direct measuring system, wherein a passage for the coil body is formed at an upper end and a lower end of the housing.

6. The direct measuring system according to claim 5 , wherein:
the coil body is guided through the passage spaced apart with a surrounding gap which defines a maximum horizontal play between the coil body and the device housing.

7. The direct measuring system according to claim 5 , wherein:
at least one knob, which is raised relative to the bar, is formed on the bar, and defines a distance to the pole shoe as a maximum vertical play.

8. The direct measuring system according to claim 5 , wherein:
at least one stiffening is formed between the shaft region and the bar; and
a recess for mounting of the at least one stiffening is formed on the pole shoe such that the stiffening and the recess protect the coil body from distortion relative to the device housing.

9. The direct measuring system according to claim 3 , wherein:
the at least one parallel-guiding member electrically integrated in the controllable electrical circuit has two current conductors isolated from one another, such that each conductor track of the coil body is connected to a respective current conductor of the at least one parallel-guiding member.

10. The direct measuring system according to claim 3 , wherein:
two parallel-guiding members are electrically integrated in the controllable electrical circuit, such that each conductor track of the coil body is connected to the current conductor of one respective link of the two parallel-guiding members.

11. The direct measuring system according to claim 10 , wherein:
the two parallel-guiding members that are electrically integrated in the controllable electrical circuit consist completely of an electrically conductive material or have at least one electrically conductive surface, the coil body has a respective end surface on the ends thereof, said end surface being formed respectively as a contact point electrically connected to one of the two conductor tracks via said end surfaces the respective parallel-guiding member is contacted and is thereby electrically integrated in the controllable electrical circuit.

12. The direct measuring system according to claim 1 , further comprising:
a device housing of the force-compensation device; and
for each of the parallel-guiding members, a fixed parallel leg and a moveable parallel leg, formed in the parallel-guiding member by suitable perforations, with at least one parallel guide that connects said parallel legs, wherein the parallel-guiding members are durably attached to the device housing, at the fixed parallel legs thereof,
by means of an electrically isolating adhesive; or
on an electrically isolating intermediate layer by means of an adhesive.

13. The direct measuring system according to claim 1 , further comprising:
a device housing of the force-compensation device; and
for each of the parallel-guiding members, a fixed parallel leg and a moveable parallel leg, formed in the parallel-guiding member by suitable perforations, with at least one parallel guide that connects said parallel legs, wherein the parallel-guiding members are durably soldered, at the fixed parallel legs thereof, on a respective circuit board and the parallel-guiding members are a component of the respective circuit board, and that the respective circuit boards are attached to the device housing by means of screws or by means of adhesive.

14. The direct measuring system according to claim 13 , wherein:
the circuit boards are formed as a single-part circuit board module connected through a flexible conductive strip.

15. The direct measuring system according to claim 1 , further comprising:
a position sensor, such that, in an operative configuration with one of the parallel-guiding members arranged above the other, defining an upper parallel-guiding member and a lower parallel-guiding member, the position sensor is arranged either over the upper parallel-guiding member or below the lower parallel-guiding member.

16. The direct measuring system according to claim 1 , wherein:
the coil body has at least two conductor tracks electrically isolated from one another, a first of the conductor tracks leading to the coil and a second of the conductor tracks leading away from the coil.

Assignees

• Mettler Toledo Gmbh

Inventors

• Reber Daniel
• Birrer Adrian
• Lang Christoph

Classifications

• G01G21/24

  Guides or linkages for ensuring parallel motion of the weigh-pans · CPC title

• G01G7/02 Primary

  by electromagnetic action · CPC title