JPH0450596B2 - - Google Patents
Info
- Publication number
- JPH0450596B2 JPH0450596B2 JP57036517A JP3651782A JPH0450596B2 JP H0450596 B2 JPH0450596 B2 JP H0450596B2 JP 57036517 A JP57036517 A JP 57036517A JP 3651782 A JP3651782 A JP 3651782A JP H0450596 B2 JPH0450596 B2 JP H0450596B2
- Authority
- JP
- Japan
- Prior art keywords
- magnetic
- developer
- concentration
- detection device
- shielding member
- 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 - Lifetime
Links
Classifications
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
- G03G15/00—Apparatus for electrographic processes using a charge pattern
- G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
- G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
- G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
- G03G15/0848—Arrangements for testing or measuring developer properties or quality, e.g. charge, size, flowability
- G03G15/0849—Detection or control means for the developer concentration
- G03G15/0853—Detection or control means for the developer concentration the concentration being measured by magnetic means
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Dry Development In Electrophotography (AREA)
- Investigating Or Analyzing Materials By The Use Of Magnetic Means (AREA)
Description
【発明の詳細な説明】
この発明は、電子複写機に用いられる磁性キヤ
リアとトナーとの混合粉体である現像剤の濃度を
検知する現像剤の濃度検知装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a developer concentration detection device for detecting the concentration of a developer, which is a mixed powder of a magnetic carrier and toner, used in an electronic copying machine.
一般に、この種の二成分現像剤に用いる電子複
写機にあつては、現像剤の多くを、重量比におい
て、キヤリアに対してトナー量が３〜５％位とな
るような濃度で利用されており、複写の際にトナ
ー像として利用された量を、現像剤の濃度検知に
より、自動的に補給するようになつている。 Generally, in electronic copying machines that use this type of two-component developer, most of the developer is used at a concentration such that the toner amount is about 3 to 5% of the carrier weight ratio. The amount used as a toner image during copying is automatically replenished by detecting the developer concentration.
この種の濃度検知装置は、現像剤の濃度（重量
比）を検知する場合に、現像剤の磁気抵抗の変化
を検知するようにしたものであり、５％以下の濃
度では容易に検知でき、トナー補給も高い精度で
行うことができる。しかしながら、現像剤の濃度
を上げて、たとえば、10％程度になると、その附
近での濃度変化を検知することは、濃度変化の割
合に対する磁気抵抗の割合が殆んどないので、高
濃度の検知は極めて困難であつた。 This type of concentration detection device detects changes in the magnetic resistance of the developer when detecting the concentration (weight ratio) of the developer, and can easily detect a concentration of 5% or less. Toner replenishment can also be performed with high precision. However, when the density of the developer is increased to about 10%, for example, it is difficult to detect density changes in the vicinity because the ratio of magnetic resistance to the ratio of density changes is almost negligible. was extremely difficult.
ところで、現像剤として特に電気抵抗の高いフ
エライトキヤリアを使うものにおいては、トナー
の帯電量が高く、したがつて、キヤリアとの分離
性が困難となるので、その分濃度を高めることに
より、キヤリアとの分離を容易にして感光層上の
静電潜像への吸着を容易にすると、良質な画像を
得ることが可能となり、更には低濃度時に生ずる
静電潜像へのキヤリアの付着も防止できる等の利
点を有するようになる。 By the way, when a ferrite carrier with particularly high electrical resistance is used as a developer, the amount of charge on the toner is high and therefore it is difficult to separate it from the carrier. By making it easier to separate and adsorb to the electrostatic latent image on the photosensitive layer, it is possible to obtain high-quality images, and it is also possible to prevent carriers from adhering to the electrostatic latent image, which occurs at low concentrations. It has the following advantages.
この発明は、上述した事情を背景になされたも
ので、その目的とするところは、漏洩磁束を無し
て磁路を効果的に形成することにより、高濃度現
像剤におけるトナー濃度を精度良くかつ安定して
検知することができる現像剤の濃度検知装置を提
供することにある。 This invention was made against the background of the above-mentioned circumstances, and its purpose is to effectively form a magnetic path without leaking magnetic flux, thereby accurately and stably controlling the toner concentration in a high-density developer. An object of the present invention is to provide a developer concentration detection device that can detect the concentration of developer.
以下、この発明の各実施例を図面を参照して具
体的に説明する。第１図乃至第４図は、この発明
の第１実施例を示している。濃度検知装置１は、
磁性体２，２を形成する一対の鉄板を右左対称に
当接配置し、この当接する箇所の磁性体２，２に
コイル３を巻き付け、かつ当接する磁性体２，２
の外側に角筒４および角筒４の外側に磁気シール
ド部材５を夫々配設し、全体として角筒状に構成
されている。 Embodiments of the present invention will be specifically described below with reference to the drawings. 1 to 4 show a first embodiment of the invention. The concentration detection device 1 is
A pair of iron plates forming the magnetic bodies 2, 2 are placed in contact with each other symmetrically, and a coil 3 is wound around the magnetic bodies 2, 2 at the abutting locations, and the magnetic bodies 2, 2 in contact with each other are wound.
A square tube 4 is disposed on the outside of the rectangular tube 4, and a magnetic shielding member 5 is disposed on the outside of the rectangular tube 4, respectively, so that the entire structure is formed into a rectangular tube shape.
磁性体２は、方形状に形成された一対の鉄板を
所定間隔離間せしめて対向配置すると共に、これ
ら各鉄板の一側端中央部を幅の挾い鉄板で一体的
に連結することにより、全体として略Ｕ字状に形
成されてなり、その対向鉄板を起立した状態で配
置されている。そして、一対の磁性体２，２の挾
部を夫々当接し、この当接する箇所にボビンを配
してコイル３を巻装する。なお、コイル３の巻き
始めおよび巻き終りをリード線６，７とする構成
となつている。 The magnetic body 2 is constructed by arranging a pair of rectangular iron plates facing each other with a predetermined distance between them, and integrally connecting the central part of one side end of each iron plate with a wide iron plate. It is formed into a substantially U-shape, and is arranged with its opposing iron plate standing upright. Then, the clamp portions of the pair of magnetic bodies 2, 2 are brought into contact with each other, and a bobbin is arranged at the contact points, and the coil 3 is wound thereon. Note that the coil 3 is configured to have lead wires 6 and 7 at its beginning and end.
また、角筒４は長方体を成し、樹脂材にて成形
されてなるもので、対接する磁性体２，２の外周
面が角筒４の内周面に接するように、磁性体２，
２が角筒４内に収納固定されている。また、磁気
シールド部材５は、全体として角筒状に形成され
ていると共に、縦断面コ字状に形成されており、
電気鉄板とかフエライトコア等のように、磁気抵
抗の低い磁気特性が優れた材質で成形されてい
る。そして、磁気シールド部材５の内壁面である
コ字形部には、角筒４が収納固定され、角筒４の
三面、すなわち、上面、外側面、下面を覆つてい
る。また、濃度検知装置１は、非磁性材から成る
筒体８内に収納されている。なお、符号９は、濃
度検知装置１内に現像剤１０を充填し、コイル３
のリード線６，７に交流電流を印加することによ
り生ずる磁束、また、符号１１は現像剤１０の充
填に拘らず生ずる磁束である。 Moreover, the rectangular tube 4 is a rectangular parallelepiped and is molded from a resin material. ，
2 is housed and fixed inside the rectangular tube 4. Moreover, the magnetic shielding member 5 is formed in a rectangular tube shape as a whole, and is also formed in a U-shape in vertical section.
It is made of a material with low magnetic resistance and excellent magnetic properties, such as electric iron plate or ferrite core. A rectangular tube 4 is housed and fixed in the U-shaped inner wall surface of the magnetic shielding member 5, and covers three sides of the rectangular tube 4, that is, the upper surface, the outer surface, and the lower surface. Further, the concentration detection device 1 is housed in a cylindrical body 8 made of a non-magnetic material. Incidentally, reference numeral 9 indicates that the developer 10 is filled in the concentration detection device 1 and the coil 3 is
A magnetic flux is generated by applying an alternating current to the lead wires 6 and 7, and reference numeral 11 is a magnetic flux generated regardless of whether the developer 10 is filled.
次に、第３図を参照して現像剤１０の濃度検知
を行う回路構成について説明する。入力端子１
２，１３間には、所定の交流電圧が印加されてい
ると共に、直列接続された濃度検出装置１および
可変抵抗器１４が接続されている。そして、濃度
検知装置１の他端は、ペアトランジスタ１５を介
してダイオード１７の負極側に接続され、また、
可変抵抗１４の他端は、ペアトランジスタ１６を
介してダイオード１８の負極側に接続されてい
る。ダイオード１７の正極側は、コンデンサ１９
および抵抗２０の一端に夫々接続され、また、ダ
イオード１８の正極側は、コンデンサ２１および
抵抗２２の一端に夫々接続されている。そして、
コンデンサ１９，２１および抵抗２０，２２の接
続間は、濃度検出装置１と可変抵抗器１４との接
続間に接続され、また、抵抗２０の他端は出力端
子２３に、抵抗２２の他端は出力端子２４に夫々
接続されている。 Next, a circuit configuration for detecting the concentration of the developer 10 will be described with reference to FIG. Input terminal 1
A predetermined AC voltage is applied between 2 and 13, and the concentration detection device 1 and variable resistor 14 are connected in series. The other end of the concentration detection device 1 is connected to the negative electrode side of the diode 17 via a pair of transistors 15, and
The other end of the variable resistor 14 is connected to the negative electrode side of a diode 18 via a pair of transistors 16. The positive terminal side of the diode 17 is connected to the capacitor 19.
and one end of a resistor 20, respectively, and the positive electrode side of the diode 18 is connected to one end of a capacitor 21 and a resistor 22, respectively. and,
The connections between the capacitors 19 and 21 and the resistors 20 and 22 are connected between the concentration detection device 1 and the variable resistor 14, and the other end of the resistor 20 is connected to the output terminal 23, and the other end of the resistor 22 is connected to the output terminal 23. They are connected to output terminals 24, respectively.
次に、上述のように構成された現像剤の濃度検
知装置１の作用について説明する。入力端子１
２，１３間に交流電圧を印加すると、コイル３に
は電流が流れて磁界が生じ、それにより磁束１１
は、磁性体２の挾部から発生し、磁性体２の対向
面および角筒４を貫き通つて磁気シールド部材５
に入り、そして、磁気シールド部材５内を通過し
て磁性体２に入り、その挾部へ戻る磁気回路を形
成する。この磁束１１は、現像剤１０の収納有無
に無関係である濃度検知装置１固有の磁束であ
る。 Next, the operation of the developer concentration detection device 1 configured as described above will be explained. Input terminal 1
When an alternating current voltage is applied between 2 and 13, a current flows through the coil 3 and a magnetic field is generated, thereby increasing the magnetic flux 11.
is generated from the clamping part of the magnetic body 2, penetrates the opposing surface of the magnetic body 2 and the rectangular tube 4, and enters the magnetic shielding member 5.
Then, it passes through the inside of the magnetic shielding member 5, enters the magnetic body 2, and returns to the clamping part to form a magnetic circuit. This magnetic flux 11 is unique to the concentration detection device 1 and is independent of whether or not the developer 10 is stored.
而して、濃度検知装置１内に現像剤１０が満さ
れると、コイル３の近傍にも現像剤１０による磁
路（図示せず）が形成されると共に、磁性体２の
対向面にも磁路（図示せず）が形成されるが、更
に、磁性体２および磁気シールド部材５の端縁に
は、現像剤１０を介して磁束９が流出し、反対側
から流入し、一巡する磁気回路が形成される。こ
のように、現像剤１０を介して磁束が流れ、この
磁束が現像剤１０の濃度に関連して変化し、これ
がコイル３の自己インダクタンスの変化、換言す
れば、コイル３のリアクタンスの変化をももた
す。このコイル３のインダクタンスの変化による
リアクタンスの変化は、現像剤１０の濃度変化に
対応して変化するようになる。 When the concentration detection device 1 is filled with the developer 10, a magnetic path (not shown) is formed by the developer 10 near the coil 3, and also on the opposing surface of the magnetic body 2. A magnetic path (not shown) is formed, and a magnetic flux 9 flows out through the developer 10 to the edges of the magnetic body 2 and the magnetic shield member 5, and flows in from the opposite side, causing a magnetic flux 9 to circulate around the edges. A circuit is formed. In this way, a magnetic flux flows through the developer 10, and this magnetic flux changes in relation to the concentration of the developer 10, which causes a change in the self-inductance of the coil 3, in other words, a change in the reactance of the coil 3. Also bring. The change in reactance due to the change in the inductance of the coil 3 changes in accordance with the change in the concentration of the developer 10.
この場合、濃度検知装置１内を流れる磁束は、
磁気抵抗の低い磁気シールド部材５を介して流れ
るので、外部には磁束の漏れがなく、したがつ
て、外部の現像剤有無に拘らず、濃度検知装置１
は、その内部に流れる現像剤の濃度を高精度に検
知可能とする。すなわち、一般に、濃度検知装置
１は、その内部に流れる現像剤のほかに、その外
部にも現像剤が流れることがあるが、濃度検知装
置１はその外側部が磁気シールド部材５で形成さ
れているので、外部現像剤の存在或は内部現像剤
の規則的な流れに対する外部現像剤の不規則な流
れによる悪影響を、確実に防止できる。特に、現
像剤の濃度が高い場合には、一層効果的である。
このように、現像剤１０の濃度検知は、外部に流
れる或は外部に存在する現像剤による悪影響を受
けないように、磁気シールド部材５が形成されて
いるので、その検知は高濃度下においても濃度変
化に対する検知を高精度に行うことができる。 In this case, the magnetic flux flowing inside the concentration detection device 1 is
Since it flows through the magnetic shield member 5 with low magnetic resistance, there is no leakage of magnetic flux to the outside, and therefore, the concentration detection device 1 can be used regardless of the presence or absence of external developer.
enables highly accurate detection of the concentration of developer flowing inside. That is, in general, in addition to the developer flowing inside the density detection device 1, developer may also flow outside the density detection device 1; Therefore, it is possible to reliably prevent the adverse effects of the presence of external developer or the irregular flow of external developer on the regular flow of internal developer. This is particularly effective when the concentration of the developer is high.
In this way, the detection of the concentration of the developer 10 is possible even under high concentrations because the magnetic shield member 5 is formed so as not to be adversely affected by the developer flowing outside or existing outside. Concentration changes can be detected with high precision.
第４図は、濃度変化に対応して変化する出力端
子２３，２４間の検出電圧曲線図である。先ず、
濃度検知装置１内に、濃度10％の現像剤を満し、
可変抵抗器１４を調節し、出力端子２３，２４間
の電圧を零とする。次いで、濃度検知装置１内の
現像剤を濃度９％の現像剤に入れ替えると、出力
端子２３，２４間には、約50mvの電圧が生ずる。
このため、現像剤の高濃度下においても濃度変化
に対する検知が可能となる。この結果、トナーの
補給も確実かつ安定して行うことができるので、
常に一定した濃度の現像剤を確保し得、良質の複
写像を得ることができる。 FIG. 4 is a detection voltage curve diagram between the output terminals 23 and 24 that changes in response to concentration changes. First of all,
Fill the concentration detection device 1 with developer with a concentration of 10%,
The variable resistor 14 is adjusted to make the voltage between the output terminals 23 and 24 zero. Next, when the developer in the concentration detection device 1 is replaced with a developer having a concentration of 9%, a voltage of approximately 50 mV is generated between the output terminals 23 and 24.
For this reason, it is possible to detect changes in density even when the developer is at a high concentration. As a result, toner replenishment can be performed reliably and stably.
A constant concentration of developer can be ensured at all times, and high-quality copied images can be obtained.
次に、この発明の他の実施例を第５図乃至第１
２図を参照して説明する。なお、第５図乃至第１
２図において、第１図および第２図で示したもの
と略同様に機能するものは、同一番号にハイフン
を付し、かつ実施例を示す連番を付して示す。 Next, other embodiments of the present invention are shown in FIGS. 5 to 1.
This will be explained with reference to FIG. In addition, Figures 5 to 1
In FIG. 2, components that function substantially in the same way as those shown in FIGS. 1 and 2 are indicated by the same numbers with a hyphen and serial numbers indicating the embodiments.
先ず、第５図および第６図は、この発明の第２
実施例を示している。本実施例は、上記第１実施
例と異なり、濃度検知装置１−２は、磁性体２−
２の高さH1を磁気シールド部材５−２の高さH2
と等しくすると共に、磁気シールド部材５−２の
形状を上記第１実施例の如く、断面コ字形に形成
せず、平板状に形成して成るもので、本実施例に
おいても、上記実施例と同様の効果が得られる。 First, FIGS. 5 and 6 show the second embodiment of this invention.
An example is shown. In this embodiment, unlike the first embodiment, the concentration detection device 1-2 has a magnetic material 2-
The height H 1 of the magnetic shielding member 5-2 is the height H 2 of the magnetic shielding member 5-2.
In addition, the shape of the magnetic shielding member 5-2 is not U-shaped in cross section as in the first embodiment, but is formed in a flat plate shape. A similar effect can be obtained.
第７図および第８図は、この発明の第３実施例
を示している。本実施例は、上記第１および第２
実施例とは異なり、濃度検知装置１−３は、一対
の磁性体を設ける構成ではなく、ひとつの磁性体
２−３で構成し、小型化を図ると共に、コイル３
−３を磁性体２−３の挾部に巻装し、かつ磁気シ
ールド部材５−３を上記第２実施例と同様に平板
状に形成し、磁性体２−３の高さを磁気シールド
部材５−３の高さH3と等しくしたものである。
本実施例においても、現像剤の高濃度化における
濃度変化を確実に検知可能であるという効果を生
ずることは、上記第１実施例と同様である。 7 and 8 show a third embodiment of the invention. In this example, the first and second
Unlike the embodiment, the concentration detection device 1-3 is not configured with a pair of magnetic bodies, but is configured with a single magnetic body 2-3 to achieve miniaturization and a coil 3.
-3 is wound around the clamp part of the magnetic body 2-3, and the magnetic shielding member 5-3 is formed into a flat plate shape similarly to the second embodiment, and the height of the magnetic body 2-3 is set to the magnetic shielding member. It is made equal to the height H3 of 5-3.
This embodiment also has the effect of being able to reliably detect changes in the concentration when the developer is highly concentrated, as in the first embodiment.
第９図および第１０図は、この発明の第４実施
例を示している。本実施例は上記第３実施例と同
様に、濃度検知装置１−４をひとつの磁性体２−
４で構成するが、磁性体２−４の高さH5は、磁
気シールド部材５−４の高さH6より低く、かつ、
磁気シールド部材５−４の形状を第１実施例と同
様に断面コ字形に形成して成るものである。 9 and 10 show a fourth embodiment of the invention. In this embodiment, as in the third embodiment, the concentration detection device 1-4 is connected to one magnetic body 2-4.
4, the height H5 of the magnetic body 2-4 is lower than the height H6 of the magnetic shielding member 5-4, and
The magnetic shielding member 5-4 is formed to have a U-shaped cross section as in the first embodiment.
第１１図および第１２図は、この発明の第５実
施例を示している。本実施例は、上記第３実施例
と同様に、濃度検知装置１−５はひとつの磁性体
２−５で構成されたもので、本実施例の場合、濃
度検知装置１−５の給送口、排出口において、給
送口の長さl1は排出口の長さl2よりも小さく、か
つ給送口の幅W1は排出口の幅W2よりも小さくな
るように、磁性体２−５の対向面が夫々台形に形
成されていると共に、各対向面を内側に夫々傾斜
せしめた構成となつている。この磁性体２−５の
形状に沿わせて角筒４−５の内壁も同様に形成さ
れ、また、その外壁面は垂直面であり、磁気シー
ルド部材５−５によつて覆われる構成となつてい
る。また、濃度検知装置１−５の排出口側には、
蓋体２５が開閉自在に装着されており、濃度検知
装置１−５内の現像剤をその開成により、所定方
向に排出するようになつている。而して、このよ
うに構成された濃度検知装置１−５によれば、上
記各実施例と同様に、現像剤の高濃度下における
濃度変化を確実に検知可能であるという効果を有
するほか、濃度検知装置１−５の給入口を排出口
よりも小さく形成したので、それだけ小型化が可
能であると共に、その排出口側が末広がり状に形
成されているので、現像剤の詰まり防止が可能
で、現像剤の流動性を高め得る。このように、濃
度検知装置１−５を小型化しても現像剤の流動性
を損うことはない。 11 and 12 show a fifth embodiment of the invention. In this embodiment, as in the third embodiment, the concentration detection device 1-5 is composed of one magnetic body 2-5, and in this embodiment, the concentration detection device 1-5 is At the inlet and outlet, the magnetic material should be The opposing surfaces 2-5 are each formed into a trapezoidal shape, and each opposing surface is inclined inward. The inner wall of the rectangular tube 4-5 is similarly formed along the shape of the magnetic body 2-5, and the outer wall surface is a vertical surface and is covered by the magnetic shield member 5-5. ing. In addition, on the discharge port side of the concentration detection device 1-5,
A lid body 25 is attached so as to be openable and closable, and when the lid body 25 is opened, the developer inside the concentration detection device 1-5 is discharged in a predetermined direction. According to the concentration detection device 1-5 configured in this manner, in addition to being able to reliably detect changes in the concentration of the developer under high concentration conditions, as in each of the above-described embodiments, Since the inlet of the concentration detection device 1-5 is formed to be smaller than the outlet, it is possible to downsize the device accordingly, and since the outlet side is formed in a shape that widens toward the end, it is possible to prevent clogging of the developer. The fluidity of the developer can be improved. In this way, even if the density detection device 1-5 is downsized, the fluidity of the developer is not impaired.
なお、上述した各実施例にあつては、コイルが
単体であるが、この発明はこれに限らず、複数個
のコイルを設ける構成であつてもよいと共に、磁
性体の数は３つ以上であつてもよい。 In addition, in each of the above-mentioned embodiments, the coil is a single unit, but the present invention is not limited to this, and a configuration in which a plurality of coils are provided may be used, and the number of magnetic bodies may be three or more. It may be hot.
また、上記各実施例は、角筒を介して磁気シー
ルド部材を配置するようにしたが、角筒を設けず
に、磁性体と磁気シールド部材とを所定間隔離間
せしめて空気層を設けるようにしてもよい。 Further, in each of the above embodiments, the magnetic shielding member is arranged through a square tube, but instead of providing a square tube, the magnetic material and the magnetic shielding member are separated by a predetermined distance to provide an air layer. It's okay.
以上詳細に説明したように、この発明に係る濃
度検知装置によれば、磁性キヤリアとトナーとの
混合粉体である現像剤が流れる通路にコイルを設
け、かつコイルと非接触状態で磁気回路中に磁気
シールド部材を配置する構成であるから、磁気シ
ールド部材内の現像剤に対しては前記コイルの磁
気回路を磁性体、現像剤、磁気シールド部材を
夫々介して形成されると共に外部の現像剤に対し
ては磁気的なシールドが行い得る。この結果、漏
洩磁束を無くして磁気回路を効果的に形成するこ
とができ、外部からの影響を受けることなく高濃
度現像剤におけるトナー濃度を精度良くかつ安定
して検知できるという優れた効果を有する。 As explained in detail above, according to the concentration detection device according to the present invention, the coil is provided in the path through which the developer, which is a mixed powder of magnetic carrier and toner, flows, and the coil is inserted into the magnetic circuit in a non-contact state. Since the magnetic shielding member is disposed in the magnetic shielding member, the magnetic circuit of the coil is formed via the magnetic material, the developer, and the magnetic shielding member, respectively, and the developer in the external Magnetic shielding can be used for this purpose. As a result, it is possible to effectively form a magnetic circuit by eliminating leakage magnetic flux, and it has the excellent effect of being able to accurately and stably detect the toner concentration in a high-density developer without being affected by external influences. .
図面はこの発明の各種実施例を示し、第１図乃
至第４図は、この発明の第１実施例で、第１図は
一部破断斜視図、第２図は要部の概略断面図、第
３図は回路構成図、第４図は検出電圧が現像剤の
濃度変化に応じて変化する状態を示した特性曲線
図、第５図および第６図はこの発明の第２実施例
を示し、第５図は一部破断斜視図、第６図は平面
図、第７図および第８図はこの発明の第３実施例
を示し、第７図は一部破断斜視図、第８図は平面
図、第９図および第１０図はこの発明の第４実施
例を示し、第９図は一部破断斜視図、第１０図は
要部の概略断面図、第１１図及び第１２図はこの
発明の第５実施例を示し、第１１図は斜視図、第
１２図は断面図である。
１，１−２，１−３，１−４，１−５……濃度
検知装置、２，２−１，２−２，２−３，２−
４，２−５……磁性体、３，３−２，３−３，３
−４，３−５……コイル、５，５−２，５−３，
５−４，５−５……磁気シールド部材。
The drawings show various embodiments of the present invention, and FIGS. 1 to 4 show a first embodiment of the invention, in which FIG. 1 is a partially cutaway perspective view, and FIG. 2 is a schematic sectional view of the main part. FIG. 3 is a circuit configuration diagram, FIG. 4 is a characteristic curve diagram showing how the detection voltage changes in response to changes in developer concentration, and FIGS. 5 and 6 show a second embodiment of the present invention. , FIG. 5 is a partially cutaway perspective view, FIG. 6 is a plan view, FIGS. 7 and 8 show a third embodiment of the present invention, FIG. 7 is a partially cutaway perspective view, and FIG. 8 is a partially cutaway perspective view. A plan view, FIGS. 9 and 10 show a fourth embodiment of the present invention, FIG. 9 is a partially cutaway perspective view, FIG. 10 is a schematic sectional view of the main part, and FIGS. 11 and 12 are A fifth embodiment of the invention is shown, with FIG. 11 being a perspective view and FIG. 12 being a sectional view. 1, 1-2, 1-3, 1-4, 1-5...Concentration detection device, 2, 2-1, 2-2, 2-3, 2-
4,2-5...magnetic material, 3,3-2,3-3,3
-4,3-5...Coil, 5,5-2,5-3,
5-4, 5-5...Magnetic shielding member.
Claims (1)
像剤が流れる通路に設けられたコイルと、 該コイルに密着され該コイルにより形成される
磁気回路に設けられた磁性体と、 該磁性体と非接触状態で前記磁性体の外側に配
置された磁気シールド部材とを具備し、 該磁気シールド部材により、該磁気シールド部
材内の現像剤に対しては前記コイルの磁気回路を
前記磁性体、現像剤、磁気シールド部材を夫々介
して形成すると共に外部に対しては磁気的なシー
ルドを行うようにしたことを特徴とする現像剤の
濃度検知装置。[Scope of Claims] 1. A coil provided in a passage through which a developer, which is a mixed powder of magnetic carrier and toner, flows, and a magnetic body provided in a magnetic circuit that is in close contact with the coil and formed by the coil. , a magnetic shielding member disposed outside the magnetic body in a non-contact state with the magnetic body, and the magnetic circuit of the coil is connected to the developer in the magnetic shielding member by the magnetic shielding member. A developer concentration detecting device characterized in that the magnetic material, the developer, and the magnetic shielding member are formed through each other, and magnetically shielded from the outside.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3651782A JPS58153974A (en) | 1982-03-10 | 1982-03-10 | Developer concentration detection device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3651782A JPS58153974A (en) | 1982-03-10 | 1982-03-10 | Developer concentration detection device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58153974A JPS58153974A (en) | 1983-09-13 |
| JPH0450596B2 true JPH0450596B2 (en) | 1992-08-14 |
Family
ID=12472005
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3651782A Granted JPS58153974A (en) | 1982-03-10 | 1982-03-10 | Developer concentration detection device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58153974A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS61160778A (en) * | 1985-01-08 | 1986-07-21 | Sharp Corp | Concentration of controlling device of developer |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS55164850A (en) * | 1979-06-12 | 1980-12-22 | Copyer Co Ltd | Toner concentration detector |
-
1982
- 1982-03-10 JP JP3651782A patent/JPS58153974A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58153974A (en) | 1983-09-13 |
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