JPH08210902A - Weight detection unit connecting member - Google Patents

Abstract

PURPOSE: To prevent an unevenly loaded load error by providing a cone shaped recessed portion in the moving portion of a cantilever weight detection member, and fitting a shaft member having a conical portion in a coupling portion with the recessed portion of a coupling member coupling the cantilever weight detection member and a lever mutually. CONSTITUTION: A pivot shaft 1 is composed of a lower conical portion 2 whose apex angle is approximately 90 degrees, and an upper cylindrical shaft 3 in the upper end of which a slitting 4 is set. In a suspension ring 5, a V blade 6 is set on its lower side, its upper side is bent by 90 degrees, and a shaft hole 7 into which the shaft 1 is fitted is provided in its central portion. After inserting the shaft 1 into the suspension ring 5, the slitting 4 of the shaft 1 is opened right and left so as to prevent the falling-out the shaft 1 from the shaft hole 7. A conical hole 9 with approximately 120 degrees bearing the shaft 1 is set in the front of the fitting member 8, a screw hole 10 for fastening the member 8 to a weight detection member in the rear thereof. When the lower conical portion 2 of the shaft 1 is suspended on the conical hole 9 of the member 8 so as to free in floating, the conical portion 2 is suspended on the conical hole 9 by the apex thereof so as to touch thereto stably. A V slot 14 for suspending a lever assembly 11 to the V blade 6 of the suspension ring 5 is set in the tip portion of a fixing plate 13 fixing the lever 12.

Description

Detailed Description of the Invention

[0001]

[Industrial application] The weight detection part of a capacitance scale, in which a fixed electrode plate for detecting capacitance and a movable electrode plate are attached to the fixed end and the movable end of a cantilever type weight detection member, respectively. Regarding improvement of a connecting member.

[0002]

2. Description of the Related Art As a connecting member of a capacitance type weight detecting unit using a conventional cantilever type weight detecting member, as shown in FIG. 4, a V groove (109) of the weight detecting unit and a mounting table are used. Via a suspension ring (105), which is a mouth-shaped member having V blades (106, 106) provided on the inside and below between the V groove (14) at the tip of the lever for transmitting the load to the weight detection unit. It was done.
(See (F) in FIG. 1)

[0003]

The conventional weight detecting member and the lever are connected by a V groove of the weight detecting portion and a V blade of the connecting member.
Since the weight is transmitted by engaging the V groove of the lever tip with the V blade of the connecting member, the meshing becomes unstable due to the processing accuracy of the V groove and V blade, and the lever inclination due to the eccentric load. (Partial contact, change in contact position due to eccentric load on the mounting table, V blade contacting a position other than V groove, etc.), the movable end of the cantilever type weight detection member becomes vertical. There was a problem that it did not descend, and therefore the gap between the fixed electrode attached to the fixed end and the movable electrode attached to the movable end was not parallel, and the correct displacement amount could not be detected and the accuracy of the scale could not be maintained. .

[0004]

A movable portion of a cantilever type weight detecting member is provided with a conical concave portion and is connected to a concave portion which is one of connecting members for connecting the cantilever type weight detecting member and the lever. A shaft member having a conical portion at the tip is fitted in the portion.

[0005]

Function: Transmission of force to the cantilever type weight detecting member is movably carried out to the conical recess of the weight detecting member by means of a shaft member having a conical portion at one end fitted to one of the connecting members. As a result, even if the machining accuracy of the other V blade of the connecting member and the V groove at the tip of the lever is poor, or the lever is tilted due to an eccentric load or the like, the contact point of the weight detecting member does not change, and Stable contact is maintained.

[0006]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view of a connecting member and its assembly perspective view of an embodiment of the present invention, (A) is a perspective view of a pivot shaft which constitutes the connecting member, (B) is a perspective view of a suspension ring which constitutes the connecting member, and (C). )
Is a perspective view of a state in which the pivot shaft is fitted to the suspension ring, (D) is a perspective view of a mounting member that constitutes the connecting member, and (E) is a member in which the pivot shaft is fitted to the suspension ring is suspended on the mounting member. (F) is a perspective view of a lever for transmitting a force to the cantilever type weight detecting unit, and FIG. 2 is a cantilever type weight detecting member in which the connecting member of the embodiment of the present invention is attached to the cantilever type weight detecting member. A perspective view of a state in which a fixed electrode plate and a movable electrode plate for capacitance detection are attached below the beam type weight detection member, and FIG. 3 is a cantilever type weight detection device to which a connecting member of the embodiment of the present invention is attached. FIG. 4 is an exploded perspective view of a portion, and FIG. 4 is a view of a conventional connecting member.

The connecting member of the weight detecting portion of the electrostatic capacity type balance using the conventional cantilever type weight detecting member shown in FIG. 4 serves to load the V groove of the weight detecting portion and the loading table (not shown). The V groove (1) of the tip of the lever (see (F) in FIG. 1) transmitted to the weight detection unit.
4) via the suspension ring (105), which is a mouth-shaped member provided with V blades (106, 106) on the upper and lower sides on the inside, but in this method, the V blade of the suspension ring is V at the tip of the lever
It is not located exactly in the groove, it shifts back and forth and the lever ratio changes,
The problem that the amount of flexure of the weight detecting member changes due to displacement in the V-shaped groove (109) of the weight detecting unit and back and forth is the same as in a scale using a strain gauge.

However, in the electrostatic capacity type balance using the cantilever type weight detecting member, when the load is biased to the left side or the right side of the table (not shown), the amount of drop of the lever on the left and right is different and The V groove of the tip portion is tilted to the left and right, and the movable portion of the weight detection member is also tilted to the left and right via the suspension ring, so that the movable electrode plate disposed in the movable portion of the weight detection member is parallel to the fixed electrode plate. However, there is a problem peculiar to the capacitance type balance that a measurement error occurs due to an eccentric load.

As a method of eliminating the measurement error due to the eccentric load of a general scale, which detects the displacement amount of the strain element of a Roberval scale without a lever as a change in the capacitance between two electrode plates. However, there is a method of bending an electrode plate as in Japanese Patent Laid-Open No. 2-17067, but in a thin scale in which the thickness of the entire scale is limited, the Roberval strain element is thick. A cantilever type weight detecting member system which cannot be used and which uses a single flexure element is general.

An embodiment of the present invention which solves this problem is shown in FIG. 1 for the connecting member and in FIGS. 1A shows a pivot shaft (1), a lower conical portion (2) has an apex angle of about 90 degrees, and an upper portion has a cylindrical shaft (3) with a slit (4) at its upper end. ) Is provided. FIG.
(B) is a suspension ring (5), a V edge (6) is provided on the lower side, the upper side is bent at 90 degrees, and a shaft hole (7) for fitting a pivot shaft in the center is formed. ) Is provided. This shaft hole has a diameter slightly larger than the diameter of the cylindrical shaft of the pivot shaft. FIG. 1 (C) is a diagram of a suspension ring assembly in which the pivot shaft is fitted in the shaft hole of the suspension ring. By making it slightly larger than the diameter of the shaft hole of the wheel, the pivot shaft does not fall out of the shaft hole.

FIG. 1D shows a mounting member (8), which has a bottom of a hole which is a recess for receiving the pivot shaft in the front.
A 20-degree conical hole (9) is provided, and a screw hole (10) for fixing the attachment member to the weight detection member is provided on the rear side. FIG. 1 (E) is a view in which the suspension ring assembly is suspended on the mounting member, and the lower conical portion of the pivot shaft is suspended freely in the conical hole of the mounting member. As described above, the contact is stable because the conical portion with the apex angle of 90 degrees is suspended in the 120 degree conical hole. 1F is a mounting table (not shown)
With the lever assembly (11) that transfers the load to the weight detection member,
Fixed plate (1) that attaches the left and right levers (12, 12)
A V groove (14) for suspending the lever assembly on the V blade of the suspension ring is provided at the tip of 3).

FIG. 2 shows that the suspension ring assembly is suspended on a mounting member attached to the cantilever type weight detecting member (15) and a capacitance type is used as a means for detecting the displacement amount of the weight detecting member. An insulating member (16) is provided below the cantilever type weight detecting member.
A fixed gap (17) is provided through the fixed electrode plate (1
8) and the movable electrode plate (19) are attached. FIG.
FIG. 3 is a developed perspective view of FIG. 2.

[0013]

As described above, by transmitting the lever force of the weighing scale to the weight detecting member through the pivot shaft fitted to the upper side of the suspension ring, the load position is biased toward the platform of the weighing scale. Even if is tilted, the detection member always bends in the vertical direction, so that the fixed electrode plate and the movable electrode plate are kept parallel,
There is an excellent effect that an eccentric load error does not occur.

[Brief description of drawings]

FIG. 1 is a view of a connecting member according to an embodiment of the present invention.

FIG. 2 is an assembly view of a connecting member according to an embodiment of the present invention.

FIG. 3 is a development view of a cantilever type weight detection unit to which a connecting member according to an embodiment of the present invention is attached.

FIG. 4 is a view of a conventional connecting member.

[Explanation of symbols]

 1 Pivot shaft 2 Conical part 3 Cylindrical shaft 4 Sliding ring 5 Suspension ring 6 V blade 7 Shaft hole 8 Mounting member 9 Conical hole 10 Screw hole 11 Lever assembly 12 Lever 13 Fixing plate 14 V groove 15 Cantilever type weight detection Member 16 Insulating member 17 Gap 18 Fixed electrode plate 19 Movable electrode plate 105 Suspension ring 115 Cantilever type weight detection member

Claims (1)

[Claims] 1. A capacitance type weight detection unit for electrically detecting a displacement amount of a weight detection unit by attaching a fixed electrode plate to a fixed end of a cantilever type weight detection member and a movable electrode plate to a movable end thereof. In a connecting member for connecting a cantilever type weight detecting member and a lever for transmitting a load of a mounting table to a weight detecting portion, a connecting blade is provided with a V blade at a connecting portion with a V groove at the tip of the lever. A coupling member for a weight detection unit, in which a shaft member having a conical portion at the tip is fitted in a coupling portion with a conical recess provided in the movable portion of the cantilever type weight detection member.