JPS6161334B2 - - Google Patents
Info
- Publication number
- JPS6161334B2 JPS6161334B2 JP55086298A JP8629880A JPS6161334B2 JP S6161334 B2 JPS6161334 B2 JP S6161334B2 JP 55086298 A JP55086298 A JP 55086298A JP 8629880 A JP8629880 A JP 8629880A JP S6161334 B2 JPS6161334 B2 JP S6161334B2
- Authority
- JP
- Japan
- Prior art keywords
- base plate
- weight
- spring
- load cells
- stopper
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
- 230000005540 biological transmission Effects 0.000 claims description 9
- 238000006073 displacement reaction Methods 0.000 description 10
- 230000008602 contraction Effects 0.000 description 6
- 230000000694 effects Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L1/00—Measuring force or stress, in general
- G01L1/26—Auxiliary measures taken, or devices used, in connection with the measurement of force, e.g. for preventing influence of transverse components of force, for preventing overload
Description
【発明の詳細な説明】
本発明はロードセルの保護装置に関する。一般
にロードセルは重量を測定するのに用いられる
が、一定のロードセルについては当然測定し得る
重量の上限がある。これを越えた重量をのせれば
ゲージがそ性変形をして、以後正確な測定が行わ
れないばかりか、場合によつては破かいしてしま
う。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a load cell protection device. Generally, load cells are used to measure weight, but naturally there is an upper limit to the weight that a certain load cell can measure. If a weight exceeding this is placed on the gauge, the gauge will become warped and not only will it not be possible to perform accurate measurements thereafter, but may even break.
本発明は上述の点に鑑みてなされたもので極め
て簡単な構造によりロードセルを保護する装置を
提供することを目的とする。 The present invention has been made in view of the above points, and an object of the present invention is to provide a device for protecting a load cell with an extremely simple structure.
この目的は本発明によれば、複数のロードセル
に接触して配置された重量伝達板、秤量すべき物
をのせる台板、この台板を前記重量伝達板上に支
持するための相互に相等しいばね定数を有する複
数の弾性手段、及び前記台板の下面から所定距離
を隔てて下方にかつ、前記複数の弾性手段の中央
位置に配置されたストツパー部材から成り、前記
台板に所定重量以上の物をのせたときに該台板の
下面が前記ストツパーに当接することにより、前
記台板がそれ以上の下方への移動を禁止して前記
複数のロードセルを保護するようにしたことを特
徴とするロードセルの保護装置によつて達成され
る。 This object, according to the invention, includes a weight transmission plate arranged in contact with a plurality of load cells, a base plate on which the object to be weighed is placed, and a mutually compatible base plate for supporting this base plate on the weight transmission plate. It consists of a plurality of elastic means having equal spring constants, and a stopper member disposed below at a predetermined distance from the lower surface of the base plate and at the center of the plurality of elastic means, the base plate having a predetermined weight or more. The lower surface of the base plate comes into contact with the stopper when an object is placed on the base plate, thereby preventing further downward movement of the base plate and protecting the plurality of load cells. This is achieved by a load cell protection device that protects the load cell.
以下、本発明の詳細につき図面を参照して説明
する。 Hereinafter, details of the present invention will be explained with reference to the drawings.
第１図は本発明の第１実施例によるはかりに適
用したロードセルの保護装置の概略正面図である
が、図において、秤量すべき品物をのせる台板１
は一対のばね２，３によつて重量伝達板７上に支
持されている。この伝達板７は基礎４上に固定配
置された一対のロードセル５，６上に載置されて
いる。伝達板７の中央部には大きな開口が形成さ
れ、こゝをストツパー８が貫通し、基礎４上に固
定されている。ストツパー８は相等しいばね常数
を有するばね２，３間の中央部に位置するように
配置され、その先端部に形成されたストツパー部
８ａは台板１の中央部Ｏに所定距離を隔てゝ対向
している。 FIG. 1 is a schematic front view of a load cell protection device applied to a scale according to a first embodiment of the present invention. In the figure, a base plate 1 on which an item to be weighed is placed
is supported on the weight transmission plate 7 by a pair of springs 2 and 3. This transmission plate 7 is placed on a pair of load cells 5 and 6 fixedly arranged on the foundation 4. A large opening is formed in the center of the transmission plate 7, through which a stopper 8 passes and is fixed on the foundation 4. The stopper 8 is arranged to be located in the center between the springs 2 and 3 having the same spring constant, and the stopper part 8a formed at the tip thereof faces the center part O of the base plate 1 at a predetermined distance. are doing.
今、第２図に示すように品物Ｗを台板１の中央
部Ｏ上にのせたとすれば、台板１は一点鎖線の位
置から実線の位置まで下降する。この下降量ａは
ばね２，３のばね常数をそれぞれｋとし、品物の
重さをＷとすれば、ａ＝Ｗ／２ｋとなる。すなわち、
ばね２，３も、それぞれａだけ縮み、それらの復
元力は重量伝達板７を介してロードセル５，６に
伝達され、図示せずともロードセル５，６からの
電気信号は重量演算回路へと導かれ、品物の重量
が測定される。公知のようにロードセル５，６の
変形量はばね２，３の変形量ａに比べ無視し得る
程度に小さいので、台板１の下方への変位量はば
ね２，３の変形量によつてのみ定まる。 Now, if the article W is placed on the center O of the base plate 1 as shown in FIG. 2, the base plate 1 will descend from the position indicated by the dashed line to the position indicated by the solid line. This lowering amount a becomes a=W/2k, where k is the spring constant of springs 2 and 3, and W is the weight of the item. That is, the springs 2 and 3 are also compressed by a amount a, and their restoring forces are transmitted to the load cells 5 and 6 via the weight transmission plate 7, and the electrical signals from the load cells 5 and 6 are sent to the weight calculation circuit even if not shown. The weight of the item is then measured. As is well known, the amount of deformation of the load cells 5 and 6 is negligibly small compared to the amount of deformation a of the springs 2 and 3, so the amount of downward displacement of the base plate 1 depends on the amount of deformation of the springs 2 and 3. determined only.
次に、第３図に示すように品物Ｗを台板１の左
端部、すなわち２の上方にのせた場合には、ばね
２はＷ／ｋ＝2aだけ縮むが、他方のばね１は殆んど縮
まない。従つて、台板１の中央部Ｏはａだけ下方
に変位する。すなわち、品物Ｗを台板１の左端部
にのせても、台板１の中央部Ｏの変位は、中央部
Ｏに品物をのせた場合と同じである。 Next, as shown in Fig. 3, when the item W is placed on the left end of the base plate 1, that is, above 2, the spring 2 contracts by W/k = 2a, but the other spring 1 contracts almost It doesn't shrink. Therefore, the central portion O of the base plate 1 is displaced downward by a. That is, even if the article W is placed on the left end of the base plate 1, the displacement of the center portion O of the base plate 1 is the same as when the article is placed on the center portion O.
第４図は更に品物Ｗを他の位置にのせた場合を
原理的に示す。台板１に品物Ｗをのせない状態を
一点鎖線で、品物Ｗをのせた状態を実線で示す、
それぞれにおいて、中心位置、ばね２，３の支持
点を×及び〇で表わすものとする。今、ばね２，
３の支持点間をｍ：ｎの比に分つ位置に品物Ｗを
のせたとすれば、ばね２に加わる荷重Ｘ＝ｎ／ｍ＋ｎ
Ｗであり、他方のばね３に加わる荷重Ｙ＝ｍ／ｍ＋ｎ
Ｗである。従つて、ばね２の縮み量Ａ＝ｎＷ／（ｍ＋ｎ
）ｋ
であり、他方のばね３の縮み量Ｂ＝ｍＷ／（ｍ＋ｎ）ｋ
であ
る。従つて、台板１の中央部Ｏの変位量＝Ａ＋Ｂ／２
＝Ｗ／２ｋ＝ａとなり、品物Ｗを台板１のどの位置に
のせても、中央部Ｏの変位の大きさは変わらない
ことがわかる。 FIG. 4 further shows the principle of the case where the article W is placed in another position. The state where the item W is not placed on the base plate 1 is shown by a dashed line, and the state where the item W is placed on the base plate 1 is shown by a solid line.
In each case, the center position and the support points of the springs 2 and 3 are represented by × and ○. Now spring 2,
If the item W is placed at a position that divides the support points of 3 into the ratio m:n, the load applied to the spring 2 is X=n/m+n W, and the load applied to the other spring 3 is Y=m/m+n It is W. Therefore, the amount of contraction A=nW/(m+n
)k, and the amount of contraction of the other spring 3 is B=mW/(m+n)k
It is. Therefore, the amount of displacement of the center O of the base plate 1 = A + B/2 = W/2k = a, and no matter where the item W is placed on the base plate 1, the magnitude of the displacement of the center O does not change. I understand that.
なお、第２図、第３図及び第４図において説明
をわかりやすくするために台板１の変位及び傾斜
を誇張して示したが、実際にはこれらはわずかで
ある。 Although the displacement and inclination of the base plate 1 are exaggerated in FIGS. 2, 3, and 4 to make the explanation easier to understand, in reality, these are slight.
以上のように、品物Ｗを台板１上のいづれの位
置においても台板１の変位はａであり、ばね２，
３を介して品物の重量がロードセル５，６に伝達
される。この場合、ロードセル５，６に等しく荷
重がかけられなくても、後続する重量演算回路で
平均化されるので、常に一定の秤量値が得られ
る。 As mentioned above, no matter where the item W is placed on the base plate 1, the displacement of the base plate 1 is a, and the spring 2,
3, the weight of the item is transmitted to load cells 5, 6. In this case, even if the loads are not applied equally to the load cells 5 and 6, they are averaged by the subsequent weight calculation circuit, so a constant weighing value can always be obtained.
次に台板１の上にロードセル５，６の限界以上
の重量の品物がのせた場合につき説明する。第１
図に示すように、この保護装置ではロードセル
５，６の限界値に相応して台板１の中央部Ｏの下
面とストツパー８のストツパー部８ａとの間の距
離ｌが定められている。上述したように、台板１
上のいづれの位置に品物をのせても、台板１の中
央部Ｏの変位量は同じであるので、第１図に示す
場合の保護装置は2k×ｌの重量限界値のロード
セル５，６に対処している。すなわち、2k×ｌ
以上の重量の品物が台板１上にのせられた場合に
は、台板１の中央部Ｏの変位はｌ以上となるべき
であるが、ｌだけ変位すると台板１がストツパー
８のストツパー部８ａと当接し、これ以上変位す
ることが妨げられる。これにより、ロードセル
５，６に2k×ｌ以上の重量が加えられることが
防止される。なお、図示しないが、ストツパー部
８ａと台紙１との間に電源及び警報装置を接続し
ておけば（勿論、この場合ストツパー部８ａ及び
台板１は他の部分からは絶縁しておく）、ストツ
パー部８ａが台板１に接触すると共に、警報がな
り、のせた品物の重量がロードセル５，６の限界
値以上の重量であることが直ちに検知されること
ができる。 Next, a case will be described in which an article whose weight exceeds the limit of the load cells 5 and 6 is placed on the base plate 1. 1st
As shown in the figure, in this protection device, the distance l between the lower surface of the central portion O of the base plate 1 and the stopper portion 8a of the stopper 8 is determined in accordance with the limit values of the load cells 5 and 6. As mentioned above, the base plate 1
Since the amount of displacement of the central portion O of the base plate 1 is the same no matter where the item is placed on the top, the protection device in the case shown in Fig. 1 is the load cells 5 and 6 with a weight limit of 2k x l. are dealing with. That is, 2k×l
When an article with the above weight is placed on the base plate 1, the displacement of the central part O of the base plate 1 should be l or more, but if it is displaced by l, the base plate 1 will move to the stopper part of the stopper 8. 8a and is prevented from further displacement. This prevents a weight of 2k×l or more from being applied to the load cells 5 and 6. Although not shown, if a power source and an alarm device are connected between the stopper part 8a and the mount 1 (of course, in this case, the stopper part 8a and the mount 1 are insulated from other parts), When the stopper portion 8a comes into contact with the base plate 1, an alarm is sounded, and it can be immediately detected that the weight of the loaded item exceeds the limit value of the load cells 5 and 6.
第５図は本発明の第２実施例によるロードセル
の保護装置の平面図である。本実施例では台板１
０は４個のばね常数の相等しいばね１１，１２，
１３，１４によつて重量伝達板２０上に支持され
ている。これらのばね１〜１４は台板１０の四隅
に配置され、これらの中央部に対応して台板１０
の中央部Ｏの下方には上述の実施例で示したスト
ツパー８が設けられているものとする。 FIG. 5 is a plan view of a load cell protection device according to a second embodiment of the present invention. In this embodiment, the base plate 1
0 is four springs with equal spring constants 11, 12,
13 and 14 on the weight transfer plate 20. These springs 1 to 14 are arranged at the four corners of the base plate 10, and the springs 1 to 14 are arranged at the four corners of the base plate 10.
It is assumed that the stopper 8 shown in the above-mentioned embodiment is provided below the central portion O of.
本実施例においても、Ｘ−Ｘ線上又はＹ−Ｙ線
上に品物Ｗをのせた場合は上述の実施例と全く同
じ作用を示すことは明らかであるが、今、仮に台
板１０上の点Ｐの位置に品物Ｗをのせた場合につ
き考察してみる。 It is clear that this embodiment also exhibits exactly the same effect as the above-mentioned embodiment when the article W is placed on the X-X line or the Y-Y line. Let us consider the case where the item W is placed at the position.
すなわち、品物Ｗの重量による力の作用点をＰ
とすれば、ばね１１，１２の中心を結ぶ線と点Ｐ
を通りＸ−Ｘに平行な線との交点P1及びばね１
３，１４の中心を結ぶ線と点Ｐを通りＸ−Ｘに平
行な線との交点P2における力の配分は次のように
なる。 In other words, the point of action of the force due to the weight of the item W is P
Then, the line connecting the centers of springs 11 and 12 and the point P
Intersection point P 1 with a line parallel to X-X passing through and spring 1
The distribution of force at the intersection point P2 between the line connecting the centers of points 3 and 14 and the line passing through point P and parallel to X-X is as follows.
点P1における力W1＝ｎ１／ｍ１＋ｎ１・Ｗ、及び
点P2における力W2＝ｍ１／ｍ１＋ｎ１・Ｗ
従つてこれらの力W1，W2によるばね１１〜１
４の縮み量は次のようになる。すなわちそれぞれ
のばね常数をｋとすれば、
ばね１１の縮み量a1＝ｎ１ｎ２／（ｍ１＋ｎ１）（ｍ２
＋ｎ２）・Ｗ／ｋ
ばね１２の縮み量a2＝ｎ１ｍ２／（ｍ１＋ｎ１）（ｍ２
＋ｎ２）・Ｗ／ｋ
ばね１３の縮み量a3＝ｍ１ｎ２／（ｍ１＋ｎ１）（ｍ２
＋ｎ２）・Ｗ／ｋ
ばね１４の縮み量a4＝ｍ１ｎ２／（ｍ１＋ｎ１）（ｍ２
＋ｎ２）・Ｗ／ｋ
従つて、台板１０の中央部Ｏの下方への変位量
ａはa1＋a2＋a3＋a4／４＝Ｗ／４ｋとなり、中央部Ｏに
品物をのせた場合と同じである。 Force W 1 at point P 1 = n 1 / m 1 + n 1 · W, and force W 2 at point P 2 = m 1 / m 1 + n 1 · W Therefore, the spring 11 ~ due to these forces W 1 and W 2 1
The amount of shrinkage of 4 is as follows. That is, if each spring constant is k, the amount of contraction of the spring 11 is a 1 = n 1 n 2 / (m 1 + n 1 ) (m 2
+n 2 )・W/k Amount of contraction of spring 12 a 2 =n 1 m 2 /(m 1 +n 1 )(m 2
+n 2 )・W/k Amount of contraction of spring 13 a 3 = m 1 n 2 / (m 1 + n 1 ) (m 2
+n 2 )・W/k Amount of contraction of spring 14 a 4 = m 1 n 2 / (m 1 + n 1 ) (m 2
+n 2 )・W/k Therefore, the downward displacement a of the center O of the base plate 10 is a 1 +a 2 +a 3 +a 4 /4=W/4k, and when an item is placed on the center O is the same as
以上述べたように、第５図の保護装置において
も、品物を台板１０上のいづれの位置にのせて
も、台板１０の中央部Ｏは一定量変位する。従つ
て常にロードセル５，６の限界値重量に正確に対
処することができる。 As described above, in the protection device shown in FIG. 5 as well, the central portion O of the base plate 10 is displaced by a constant amount no matter where the article is placed on the base plate 10. Therefore, the limit value weight of the load cells 5 and 6 can always be dealt with accurately.
以上、本発明の各実施例について説明したが、
勿論、本発明はこれら実施例に限定されることな
く本発明の技術的思想に基づいて種々の変形が可
能である。 Although each embodiment of the present invention has been described above,
Of course, the present invention is not limited to these embodiments, and various modifications can be made based on the technical idea of the present invention.
例えば、実施例ではばねの数を２個と４個の場
合について説明したが、任意の複数個のばねで支
持して上述の効果を得るように構成することが可
能である。 For example, in the embodiment, the cases where the number of springs is 2 and 4 have been described, but it is possible to support the device with any number of springs to obtain the above-mentioned effect.
又、ばね材として、コイルスプリングに限らず
例えばゴムばねであつてもよい。 Further, the spring material is not limited to a coil spring, but may be a rubber spring, for example.
以上述べたように本発明によるロードセルの保
護装置は極めて簡単な構造で確実にかつ正確に限
界値重量に対処してロードセルを保護するもので
ある。 As described above, the load cell protection device according to the present invention has an extremely simple structure and protects the load cell by reliably and accurately dealing with the limit weight.
第１図は本発明の第１実施例によるロードセル
の保護装置の概略正面図、第２図及び第３図は同
装置の作用を説明するための一部破断概略正面
図、第４図は更に同はかりの作用を説明するため
の線図、及び第５図は本発明の第２実施例による
ロードセルの保護装置の平面図である。
なお、図において、１，１０……台板、２，
３，１１，１２，１３，１４……ばね、５，６…
…ロードセル、７，２０……重量伝達板、８……
ストツパー、８ａ……ストツパー部。
FIG. 1 is a schematic front view of a load cell protection device according to a first embodiment of the present invention, FIGS. 2 and 3 are partially cutaway schematic front views for explaining the operation of the device, and FIG. A diagram for explaining the operation of the scale, and FIG. 5 are a plan view of a load cell protection device according to a second embodiment of the present invention. In addition, in the figure, 1, 10... base plate, 2,
3, 11, 12, 13, 14... spring, 5, 6...
...Load cell, 7, 20... Weight transmission plate, 8...
Stopper, 8a...Stopper part.
Claims (1)
伝達板、秤量すべき物をのせる台板、この台板を
前記重量伝達板上に支持するための相互に相等し
いばね定数を有する複数の弾性手段、及び前記台
板の下面から所定距離を隔てて下方にかつ、前記
複数の弾性手段の中央位置に配置されたストツパ
ー部材から成り、前記台板に所定重量以上の物を
のせたときに該台板の下面が前記ストツパーに当
接することにより、前記台板がそれ以上の下方へ
の移動を禁止して前記複数のロードセルを保護す
るようにしたことを特徴とするロードセルの保護
装置。1. A weight transmission plate arranged in contact with a plurality of load cells, a base plate on which an object to be weighed is placed, and a plurality of elastics having mutually equal spring constants for supporting this base plate on the weight transmission plate. and a stopper member disposed below at a predetermined distance from the lower surface of the base plate and at the center of the plurality of elastic means, and when an object of a predetermined weight or more is placed on the base plate. A protection device for a load cell, characterized in that the lower surface of the base plate comes into contact with the stopper, thereby prohibiting further downward movement of the base plate to protect the plurality of load cells.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8629880A JPS5712335A (en) | 1980-06-25 | 1980-06-25 | Protecting device of load cell |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8629880A JPS5712335A (en) | 1980-06-25 | 1980-06-25 | Protecting device of load cell |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5712335A JPS5712335A (en) | 1982-01-22 |
| JPS6161334B2 true JPS6161334B2 (en) | 1986-12-25 |
Family
ID=13882921
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8629880A Granted JPS5712335A (en) | 1980-06-25 | 1980-06-25 | Protecting device of load cell |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5712335A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0787351B2 (en) * | 1985-11-19 | 1995-09-20 | 松下電器産業株式会社 | Input transition detection circuit |
-
1980
- 1980-06-25 JP JP8629880A patent/JPS5712335A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5712335A (en) | 1982-01-22 |
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