JPH0122618B2 - - Google Patents
Info
- Publication number
- JPH0122618B2 JPH0122618B2 JP20365081A JP20365081A JPH0122618B2 JP H0122618 B2 JPH0122618 B2 JP H0122618B2 JP 20365081 A JP20365081 A JP 20365081A JP 20365081 A JP20365081 A JP 20365081A JP H0122618 B2 JPH0122618 B2 JP H0122618B2
- Authority
- JP
- Japan
- Prior art keywords
- developer
- concentration
- coil
- magnetic
- cylinder
- 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
- 238000001514 detection method Methods 0.000 claims description 9
- 239000011812 mixed powder Substances 0.000 claims description 4
- 230000007423 decrease Effects 0.000 description 12
- 239000006247 magnetic powder Substances 0.000 description 7
- 239000003990 capacitor Substances 0.000 description 5
- 230000004907 flux Effects 0.000 description 5
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000006698 induction Effects 0.000 description 2
- 239000000969 carrier Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 239000012212 insulator Substances 0.000 description 1
- 238000010030 laminating Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011347 resin Substances 0.000 description 1
- 229920005989 resin Polymers 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
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)
Description
【発明の詳細な説明】
この発明は、電子複写機等の画像形成装置に用
い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 image forming apparatus such as an electronic copying machine.
一般に、この種の現像剤を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
して使用された量を、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 developer, most of the developer is used at a concentration such that the amount of toner is about 3 to 5% of the carrier by weight. The amount of toner used in the toner image during copying is determined by detecting the concentration of the developer.
It is set to replenish automatically.
この種の濃度検知装置は、現像剤の濃度（重量
比）の変化を検知する場合に、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 is designed to detect changes in the magnetic resistance of the developer when detecting changes in developer concentration (weight ratio), and can easily be detected at concentrations below 5%. It is possible to replenish toner with high precision. However, when the developer concentration is increased to about 10%, for example,
It has been extremely difficult to detect changes in concentration in the vicinity because the ratio of magnetic resistance to the rate of change in concentration is almost negligible.
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
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、良質の画像を得
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
が生ずる。したがつて、高濃度での現像剤の濃度
検知を可能とした濃度検知装置が要望されてい
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, making it difficult to separate from the carrier. By facilitating separation and adsorption to the electrostatic latent image on the photosensitive layer, it is possible to obtain high-quality images, and furthermore, it is possible to prevent carriers from adhering to the electrostatic latent image that occurs at low concentrations. The following advantages arise. Therefore, there is a need for a concentration detection device that can detect developer concentration at high concentrations.
この発明は、上述した事情を鑑みてなされたも
ので、その目的とするところは、特に、高濃度で
ある10％程度附近での濃度変化をも検知できるよ
うにした現像剤の濃度検知装置を提供することに
ある。 This invention was made in view of the above-mentioned circumstances, and its purpose is to provide a developer concentration detection device that is capable of detecting concentration changes even at high concentrations of around 10%. It is about providing.
以下、この発明を図面に示す一実施例に基づい
て具体的に説明する。第１図において、符号１
は、現像剤の濃度を検知するためのリアクターで
あり、このリアクター１は、樹脂材等の絶縁体に
より成形されている横断面矩形の筒体２と、この
筒体２の外周部に所定間隔離間せしめて巻装され
た一対のコイル３，４と、これら各コイル３，４
を跨ぐように筒体２の一側面に装着されたＥ字形
鉄心（磁路）５とから構成されてなるものであ
る。コイル３，４は、筒体２の外周部に所定回数
巻いて巻装されてなり、また、Ｅ字形磁路５は、
薄肉状のＥ字形鉄心を多数枚積層してなるもの
で、その３脚部６，７，８を夫々有し、上部の脚
部６と中間部７の脚部７との間には、コイル３が
介在され、また、中間部７の脚部７と下部の脚部
８との間には、コイル４が介在されている。そし
て、磁路５の３脚部６，７，８の先端部は、筒体
２の平面部分に密着させてある。この場合、筒体
２の平面部分に、磁路５の３脚部６，７，８を挿
入する窓（図示せず）を形成し、当該窓に磁路５
の３脚部６，７，８を挿入し、筒体２の内面と３
脚部６，７，８の端面とが面一となるようにして
もよい。 Hereinafter, the present invention will be specifically described based on an embodiment shown in the drawings. In Figure 1, reference numeral 1
1 is a reactor for detecting the concentration of developer, and this reactor 1 consists of a cylinder 2 with a rectangular cross section formed of an insulator such as a resin material, and a cylinder 2 with a predetermined interval on the outer periphery of the cylinder 2. A pair of coils 3 and 4 wound apart from each other, and each of these coils 3 and 4
It consists of an E-shaped iron core (magnetic path) 5 attached to one side of the cylinder 2 so as to straddle the cylindrical body 2. The coils 3 and 4 are wound around the outer periphery of the cylinder 2 a predetermined number of times, and the E-shaped magnetic path 5 is
It is made by laminating a large number of thin-walled E-shaped iron cores, and has three leg parts 6, 7, and 8, respectively. Between the upper leg part 6 and the leg part 7 of the middle part 7, there is a coil. 3 is interposed therebetween, and a coil 4 is interposed between the leg part 7 of the intermediate part 7 and the lower leg part 8. The tips of the three legs 6, 7, and 8 of the magnetic path 5 are brought into close contact with the flat surface of the cylinder 2. In this case, a window (not shown) into which the three leg parts 6, 7, and 8 of the magnetic path 5 are inserted is formed in the planar part of the cylinder 2, and the magnetic path 5 is inserted into the window.
Insert the three leg parts 6, 7, 8 of the cylindrical body 2 and 3
The end surfaces of the legs 6, 7, and 8 may be flush with each other.
第２図は、リアクター１の縦断面図を示し、筒
体２内には、磁性キヤリアとトナーとの混合粉体
である現像剤９が充満した状態で収容されてい
る。なお、筒体２内の現像剤９が排出されると、
新たな現像剤が補給されるようになつている。而
して、コイル３のリード線１０ａ，１０ｂ、ま
た、コイル４のリード線１１ａ，１１ｂに交流電
流が供給されると、その電流によつて生ずる磁界
により、コイル３，４に対応する交番磁束１２，
１３が現像剤９に混入されている磁性キヤリアお
よびＥ形磁路５の３脚部６，７，８の何れを介し
て流れ、コイル３，４に対応する専用の磁気回路
が形成される。 FIG. 2 shows a longitudinal cross-sectional view of the reactor 1, in which the cylinder 2 is filled with developer 9, which is a mixed powder of magnetic carrier and toner. Note that when the developer 9 in the cylinder body 2 is discharged,
New developer is being replenished. When an alternating current is supplied to the lead wires 10a and 10b of the coil 3 and the lead wires 11a and 11b of the coil 4, the magnetic field generated by the current causes an alternating magnetic flux corresponding to the coils 3 and 4. 12,
13 flows through the magnetic carrier mixed in the developer 9 and any of the three legs 6, 7, 8 of the E-shaped magnetic path 5, forming a dedicated magnetic circuit corresponding to the coils 3, 4.
次に、現像剤９の濃度検知を行なう回路は、第
３図に示す如く構成されている。すなわち、入力
端子１４，１５間には、交流電圧Viが印加され
ている。また、入力端子１４には、コンデンサ１
６、コイル４およびコイル３の各一端が夫々接続
されている。そして、コンデンサ１６およびコイ
ル４は互いに並列接続され、それらの各他端は、
整流回路１７の一方の端子に接続されている。ま
た、コイル３の他端は整流回路１８の一方の端子
に接続されている。そして、各整流回路１７，１
８の他端は入力端子１５に夫々接続され、また、
各整流回路１７，１８の出力は、比較回路１９に
夫々供給される。この比較回路１９は、各整流回
路１７，１８の出力を比較して、その大小を検知
するもので、この検知出力は、たとえば、筒体２
に対してトナーを補給するトナー補給装置（図示
せず）を作動させて、現像装置（図示せず）内の
現像剤の濃度を、一定に保つようになつている。 Next, a circuit for detecting the concentration of the developer 9 is constructed as shown in FIG. That is, an AC voltage Vi is applied between the input terminals 14 and 15. In addition, a capacitor 1 is connected to the input terminal 14.
6, one end of each of the coil 4 and the coil 3 is connected to each other. The capacitor 16 and the coil 4 are connected in parallel with each other, and their other ends are
It is connected to one terminal of the rectifier circuit 17. Further, the other end of the coil 3 is connected to one terminal of a rectifier circuit 18. And each rectifier circuit 17,1
The other ends of 8 are respectively connected to the input terminals 15, and
The output of each rectifier circuit 17, 18 is supplied to a comparison circuit 19, respectively. This comparison circuit 19 compares the outputs of the respective rectifier circuits 17 and 18 and detects the magnitude thereof, and this detection output is, for example,
A toner replenishing device (not shown) for replenishing toner is operated to maintain a constant concentration of developer in a developing device (not shown).
次に、上述のように構成された現像剤の濃度検
知装置の作用について説明する。筒体２内に現像
剤９を充満させている状態において、入力端子１
４，１５間に交流電圧Viを印加すると、コイル
３に対しては、交流電流i1が流れ、また、コイル
４に対しては、交流電流i2が流れるようになる。
この結果、コイル３による交番磁束１２は、現像
剤９の磁性粉（キヤリア）およびＥ字形磁路５の
脚部６，７を介して流れ、コイル３に対する専用
の磁気回路を形成し、また、コイル４にる交番磁
束１３は、現像剤９の磁性粉およびＥ字形磁路５
の脚部７，８を介して流れ、コイル４に対する専
用の磁気回路を形成する。 Next, the operation of the developer concentration detection device configured as described above will be explained. When the cylinder body 2 is filled with the developer 9, the input terminal 1
When an alternating current voltage Vi is applied between coils 4 and 15, an alternating current i1 flows through the coil 3, and an alternating current i2 flows through the coil 4.
As a result, the alternating magnetic flux 12 caused by the coil 3 flows through the magnetic powder (carrier) of the developer 9 and the legs 6, 7 of the E-shaped magnetic path 5, forming a dedicated magnetic circuit for the coil 3, and The alternating magnetic flux 13 in the coil 4 is caused by the magnetic powder of the developer 9 and the E-shaped magnetic path 5.
through the legs 7, 8 of the coil 4, forming a dedicated magnetic circuit for the coil 4.
この交流電流i1，i2は、結果的には、筒体２内
に存る現像剤９の磁性粉によつて形成される磁路
との係りが強く、たとえば、磁性粉の量の多い少
ないによつて、磁気抵抗が決定され、コイルの所
謂自己インダクタンスの発生および変化をもたら
すものである。そして、コイルのインダクタンス
は、磁気抵抗が少く、かつ、発生する磁束が多く
なると増し、逆に、磁気抵抗が増し、かつ発生す
る磁束が少なくなると減る。このため、現像剤９
の濃度が低下し、磁性粉の量が増すことにより、
インダクタンスが増し、逆に、濃度が上昇し、磁
性粉の量が減ると、インダクタンスが低下する。 As a result, these alternating currents i 1 and i 2 are strongly related to the magnetic path formed by the magnetic powder of the developer 9 existing in the cylinder 2. For example, when the amount of magnetic powder is large, This determines the magnetic resistance, which leads to the generation and change of the so-called self-inductance of the coil. The inductance of the coil increases when the magnetic resistance is low and the generated magnetic flux increases, and conversely, it decreases when the magnetic resistance increases and the generated magnetic flux decreases. For this reason, the developer 9
As the concentration of magnetic powder decreases and the amount of magnetic powder increases,
The inductance increases, and conversely, as the concentration increases and the amount of magnetic powder decreases, the inductance decreases.
したがつて、コイルのインダクタンスの変化に
よるリアクタンスの変化によつて、流れる電流が
変化し、この変化する交流電流i1，i2は、リアク
タンスの変化に逆比例して流れるので、現像剤９
の濃度変化に対応して変化するようになる。すな
わち、現像剤９の濃度が低下すると、電流i1，i2
は減少し、濃度が増すと、電流i1，i2は増加する
ようになる。 Therefore, the flowing current changes due to a change in reactance due to a change in inductance of the coil, and these changing alternating currents i 1 and i 2 flow in inverse proportion to the change in reactance, so the developer 9
It changes in response to changes in the concentration of. That is, when the concentration of the developer 9 decreases, the currents i 1 , i 2
decreases, and as the concentration increases, the currents i 1 and i 2 begin to increase.
第４図は、現像剤９の濃度（％）の変化に応じ
て交流電流i1，i2＋i3が変化する様子を示してい
る。ここで、交流電流i3は、コンデンサ１０に流
れる電流であり、この交流電流i3は、交流電流i1，
i2がコイル３，４のリアクタンスの変化に応じて
変化するのに対し、一定の電流である。而して、
コイル４とコンデンサ１６の並列回路における合
成電流i2＋i3において、内部抵抗を無視した場合
に、コイル４に流れる交流電流i2とコンデンサ１
６に流れる交流電流i3とは、180゜の位相差がある
ので、第４図に示す設定濃度Ａの値で、合成電流
i2＋i3の値をコイル３に流れる交流電流i1の値と
同じ値にするのが望ましい。すなわち、交流電流
i1および交流電流i2が等しい場合に、交流電流i3
を電流i2の２倍に流すことにより、
i2＋（−2i2）
となる。この場合、電流i2とi3とは、位相が180゜
異なるので、
i2＋（−2i2）＝i2−2i2＝−i2
となり、電流i1に対して合成電流i2＋i3は、逆位
相となると共に、電流の絶対値が等しくなる。第
４図は、この状態を示し、現像剤９の濃度変化に
応じて、電流i1，i2＋i3の絶対値が変化する。こ
の場合、現像剤９の濃度が低下すると、コイル４
のリアクタンスが増すので、電流i2が減少する。
一方、電流i3は一定であるので、電流i1とi2＋i3と
の差は、結果的には電流i3分が増したことにな
り、全体的には、濃度が低下すると、電流i2＋i3
は増加し、電流i1は減少し、現像剤９の濃度が低
下するにしたがつて、両者の差は大きくなる。 FIG. 4 shows how the alternating currents i 1 , i 2 +i 3 change according to changes in the concentration (%) of the developer 9. Here, the alternating current i 3 is a current flowing through the capacitor 10, and this alternating current i 3 is equal to the alternating current i 1 ,
It is a constant current, whereas i 2 changes according to changes in the reactance of the coils 3 and 4. Then,
In the composite current i 2 + i 3 in the parallel circuit of coil 4 and capacitor 16, if internal resistance is ignored, the alternating current i 2 flowing through coil 4 and capacitor 1
Since there is a phase difference of 180° with the alternating current i3 flowing through 6, the combined current is
It is desirable that the value of i 2 +i 3 be the same as the value of the alternating current i 1 flowing through the coil 3. That is, alternating current
If i 1 and alternating current i 2 are equal, alternating current i 3
By flowing twice the current i 2 , it becomes i 2 +(−2i 2 ). In this case, the currents i 2 and i 3 have a phase difference of 180°, so i 2 + (-2i 2 ) = i 2 -2i 2 = -i 2 , and the combined current i 2 + i 3 , the phases are opposite and the absolute values of the currents are equal. FIG. 4 shows this state, and the absolute values of the currents i 1 , i 2 +i 3 change in accordance with changes in the concentration of the developer 9. In this case, when the concentration of the developer 9 decreases, the coil 4
The reactance of increases, so the current i 2 decreases.
On the other hand, since the current i 3 is constant, the difference between the current i 1 and i 2 + i 3 results in an increase in the current i 3. Overall, as the concentration decreases, the current i 2 + i 3
increases, current i 1 decreases, and as the concentration of developer 9 decreases, the difference between the two increases.
而して、電流i1とi2＋i3とは、位相差があるの
で、両者の絶対値を求めるために、整流回路１
７，１８で夫々整流を行なつたのち、比較回路１
９にて両者の大小の比較が行なわれる。この比較
の結果、図示しないトナー補給装置が作動され、
現像装置内の現像剤の濃度が一定に保たれる。 Since there is a phase difference between the currents i 1 and i 2 + i 3 , in order to find the absolute value of both, the rectifier circuit 1
After rectifying at 7 and 18, the comparator circuit 1
At step 9, the magnitudes of the two are compared. As a result of this comparison, a toner supply device (not shown) is activated.
The concentration of developer in the developing device is kept constant.
このように、筒体２内に現像剤９を充満した状
態において、筒体２に巻装された一対のコイル
３，４に対応させて夫々専用の磁気回路を形成す
る構成であるから、コイル３，４間の相互誘導が
生じることがなく、現像剤９の濃度変化に対応す
るコイル３，４のリアクタの変化に基づき、正確
な濃度を検知することができる。 In this way, when the cylinder body 2 is filled with the developer 9, the coils are configured to form dedicated magnetic circuits corresponding to the pair of coils 3 and 4 wound around the cylinder body 2, respectively. Mutual induction between the coils 3 and 4 does not occur, and the concentration can be accurately detected based on changes in the reactors of the coils 3 and 4 corresponding to changes in the concentration of the developer 9.
なお、上記実施例においては、筒体に一対のコ
イルを巻装するようにしたが、２以上のコイルを
巻装するようにしてもよい。また、磁路は、Ｅ字
形に限らず、種々の形状のものであつてもよい。 In the above embodiment, a pair of coils are wound around the cylinder, but two or more coils may be wound around the cylinder. Further, the magnetic path is not limited to the E-shape, but may have various shapes.
この発明は、以上詳細に説明したように、電子
複写機等の画像形成装置に用いる磁性キヤリアと
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おいて、前記現像剤を
収容する筒体と、この筒体の外周部に所定間隔離
間せしめて夫々巻装された複数のコイルと、これ
ら各コイルを跨ぐように前記筒体の側面に装着さ
れた磁路とを具備し、前記各コイルに対応する専
用の磁気回路を前記筒体内の現像剤および磁路を
夫々介して形成する構成であるから、コイル間の
相互誘導を生じることがないので、複数のコイル
で夫々濃度変化を検出することができ、この検出
量の差に基づいて濃度検知を行なうようにすれ
ば、特に、高濃度である10％近くであつても検出
することができる。 As described in detail above, the present invention provides 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 image forming apparatus such as an electronic copying machine. A cylindrical body containing the agent, a plurality of coils wound around the outer periphery of the cylindrical body at predetermined intervals, and a magnetic path attached to the side surface of the cylindrical body so as to straddle these coils. Since a dedicated magnetic circuit corresponding to each coil is formed through the developer and the magnetic path in the cylinder, mutual induction between the coils does not occur, so it is possible to use a plurality of coils. It is possible to detect changes in the respective concentrations, and if the concentration is detected based on the difference between the detected amounts, it is possible to detect even a particularly high concentration of nearly 10%.
図面は、この発明の一実施例を示し、第１図
は、濃度検出リアクタの斜視図、第２図はリアク
タの縦断面図、第３図は回路構成図、第４図は、
各コイルに流れる電流が濃度変化に応じて変化す
る状態を示した特性曲線図である。
１……リアクタ、２……筒体、３，４……コイ
ル、５……磁路、９……現像剤。
The drawings show an embodiment of the present invention; FIG. 1 is a perspective view of a concentration detection reactor, FIG. 2 is a vertical sectional view of the reactor, FIG. 3 is a circuit configuration diagram, and FIG.
FIG. 4 is a characteristic curve diagram showing a state in which the current flowing through each coil changes according to a change in concentration. 1...Reactor, 2...Cylinder, 3, 4...Coil, 5...Magnetic path, 9...Developer.
Claims (1)
像剤の濃度を検知する現像剤の濃度検知装置にお
いて、前記現像剤を収容する筒体と、この筒体の
外周部に所定間隔離間せしめて巻装され交流電流
が供給された複数のコイルと、これら各コイルを
跨ぐように前記筒体の側面に装着された磁路とを
具備し、前記各コイルに対応する専用の磁気回路
を前記筒体内の現像剤および磁路を夫々介して形
成したことを特徴とする現像剤の濃度検知装置。1. In a developer concentration detection device that detects the concentration of a developer that is a mixed powder of a magnetic carrier and toner, a cylinder housing the developer and a coil wound around the outer periphery of the cylinder at a predetermined distance are provided. The tube includes a plurality of coils that are equipped with an AC current and a magnetic path attached to the side surface of the cylinder so as to straddle these coils, and a dedicated magnetic circuit corresponding to each coil is installed inside the cylinder. What is claimed is: 1. A developer concentration detecting device, characterized in that the device is formed through a developer and a magnetic path, respectively.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20365081A JPS58105260A (en) | 1981-12-18 | 1981-12-18 | Density detecting device of developer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20365081A JPS58105260A (en) | 1981-12-18 | 1981-12-18 | Density detecting device of developer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58105260A JPS58105260A (en) | 1983-06-23 |
| JPH0122618B2 true JPH0122618B2 (en) | 1989-04-27 |
Family
ID=16477554
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20365081A Granted JPS58105260A (en) | 1981-12-18 | 1981-12-18 | Density detecting device of developer |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58105260A (en) |
-
1981
- 1981-12-18 JP JP20365081A patent/JPS58105260A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS58105260A (en) | 1983-06-23 |
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