Plaintiff: Zhu Guangsheng, male, born on May 21, 1951,  Man Nationality, director of Jinzhou Research Institute of Electronic Technology, residing at No. 329 Nanguan Street, Yi County, Jinzhou City, Liaoning Province.

Agent ad litem: Zhu Dan, female, born on January 27, 1979, Man Nationality, employee of Jinzhou Research Institute of Electronic Technology, residing at No. 329 Nanguan Street, Yi County, Jinzhou City, Liaoning Province.

Defendant: Changchun Hongyu Electronic Energy Saving Equipment Development Company Limited, residing at No. 40 Pudong Road, Changchun Economic Development Zone.

Legal representative: Chen Lianbin, general manager.

Agent ad litem: Liu Xiangjun, male, born on August 23, 1956, Han Nationality, board chairman of Beijing Junlian Building Materials Factory, residing at Room 2904, 13th building, Tiantong Garden, Changping District, Beijing.

After accepting the patent infringement dispute case between the plaintiff Zhu Guangsheng and the defendant Changchun Hongyu Electronic Energy Saving Equipment Development Company Limited (hereinafter referred to as Hongyu Company), the court formed a collegial bench and held a public hearing of the case. The plaintiff Zhu Guangshen and his agent ad litem Zhu Dan, and the defendant Hongyu Company, its legal representative Chen Lianbin and agent ad litem Liu Xiangjun thereof were all present at the court to attend the lawsuit. This case has been concluded till now.
 
The plaintiff claims that he first creatively invented and produced "Sensor of automatic wiping water in oil" for resolving the problem that the probe of water-content tester is prone to collect wax and dirty, and has filed a patent application for Utility Model with the State Intellectual Property Office of People's Republic of China (SIPO) on July 22, 2000, and it was granted a patent right (Patent No.: ZL00212739.3) on May 2, 2001. In spring of 2003, the plaintiff found that the defendant sold and installed some products infringing his patent right in 5 oil production plants in Daqing Oilfield. Request a judgment as follows: 1. The defendant immediately stops its infringement; 2. The defendant pays a compensation for economic loss of RMB100,000 to the plaintiff.

The defendant Hongyu Company claims that the YSL-1G and YSL-1D tester for water-content in raw oil and YSLB-2G water-content in raw oil transducer produced by itself are the patented hi-tech products independently developed by itself, of which the technical features are substantially distinctive from those of existing products of the same type, and are different in principle and structure as compared with the plaintiff's patented technology, and even more advanced than the plaintiff's. As early as October 1998, the defendant had achieved success in research of the technology, and on December 4, 1998 obtained Anti-Explosion Quality Certificate for passing the technology appraisal made by the State Quality Supervision and Inspection Center for Coal Mine Anti-explosion and Safety Products, and in 1999 obtained the License for Manufacturing Measuring Instruments for passing the appraisal made by Jilin Technology Supervision Bureau. The defendant filed in November 2000 a patent application for Utility Model for "A Kind of High-precise Tester for Water-content in Raw Oil", and it was granted a patent right on October 3, 2001. The defendant has not infringed upon the plaintiff's patent right, so the court should reject the plaintiff's request.
 
During the public hearing held by the court, to prove that the facts been established for which the plaintiff and the defendant wanted to defend and claim, both the plaintiff and the defendant provided evidences and uttered inquiry opinions.

The plaintiff Zhu Guangsheng provided the following evidences:

Evidence A1: patent certificate, the claims, the descriptions and drawings thereof, 2 receipts of patent annual fee, 1 patented product, and 1 set of nut and sliding block. The main contents include: the Utility Model ZL002127393 for "Automatic Wipe Water in Oil Sensor" filed on July 22, 2000 by plaintiff and granted on May 2, 2001 by the SIPO.

Evidence A2: the tester for water-content in raw oil, product assembly drawings and one set of screw and slider reproduced by the plaintiff to prove that the structure and gearing mode of the defendant's product is the same as the plaintiff's patented technical solution.

Evidence A3: the defendant's Product Selection Guideline, photo of YSL-1G tester for water-content in raw oil (which was charged for patent infringement) mounted in No. 6 and No. 7 oil production plants of Daqing Oilfield, the claims, descriptions and drawings of the defendant's patent document, the defendant's Installation and Operation Instructions for YSL-1 D Tester for water-content in raw oil (Wiping Type), propaganda information on the defendant's company and YSL-1 D Tester for water-content in raw oil published on Changchun Science & Technology Information Net, Chapter 18 of Design Handbook of Machine Part (2nd Edition ) recording spiral driving, the printing strip and the Appraisal Report No. Jingjianzi 18616 issued by Beijing JZSC Intellectual Property Judicature Appraisal Center to prove that the defendant's product is the same as the plaintiff's patented technical solution.

Evidence A4: salary registration list that shows Cai Pengda got salaries in the plaintiff's unit from November 1997 to January 1998, borrowing registration list that shows Cai Penda once borrowed technical documents from the plaintiff's unit when he was an employee of the unit, and the photo shows Cai Pengda once was an employee of the plaintiff's unit to prove that Cai Pengda once worked for the plaintiff's unit.

Evidence A5: the defendant's sales contract (YSL-1 D Water Content in Raw Oil Tester, tax-excluded unit price: RMB75,846.20), number of sales contract for the defendant's product that was charge for patent infringement, and product price list to prove the fact that the defendant had sold the alleged infringing product and the price thereof in Daqing.

The defendant Hongyu Company holds that: there is no objection to evidence A1; evidence A2 is a reproduced tester so as to not being used as an evidence; evidence A3 can not prove the plaintiff's claim, which was issued under the entrustment privately made by the plaintiff so as to having no legal effect, and the defendant had conduced product test before the plaintiff filed application for the patent, and the defendant's product is different from the plaintiff's patent technology; for evident A4, if Cai Pengda was an employee of the plaintiff's unit, the patentee should be the unit because the invention-creation of Cai Pengda was a service invention-creation; for evidence A5, the defendant sold its own product, so it has not infringed the plaintiff's patent right.

The defendant Hongyu Company provided the following evidences:
 
Evidence B1: the defendant's business license for enterprise as a legal person to prove that, established in April 1998, the defendant started to develop the said product prior to the plaintiff's filing the patent application.

Evidence B2: Anti-Explosion Quality Certificate to prove that State Quality Supervision and Inspection Center for Coal Mine Anti-explosion and Safety Products inspected and granted on December 4, 1998 the quality certificate for the defendant's YSL-1 D Tester for water-content in raw oil.
 
Evidence B3: License for Manufacturing Measuring Instruments granted to the defendant in February 1999 by Jilin Technology Supervision Bureau to prove that the defendant had produced YSL-G and D tester for water-content in raw oil with the license for production granted by the authoritative department before the filing date of the plaintiff's patent application.

Evidence B4: Notice for Test Results on the Specimen issued in January 1999 by Jilin Measuring Products (Goods) Quality Supervision and Inspection Station to prove that the defendant had produced eligible products before the plaintiff's filing the patent application, whose technical features were different from those of the plaintiff's.

Evidence B5: the defendant's patent certificate, the claims, the descriptions and drawings, Chinese Patent Title Information. The main contents include: a patent application filed by the defendant for Utility Model for "A Kind of High-precise Tester for Water-content in Raw Oil" on November 29, 2000, the inventor is Cai Pengda, Wang Zhimin, and granted a patent right for Utility Model (patent No.: ZL00253283.2).

Evidence B6: Data Comparison Sheet of the defendant's YSL-1 D Tester for Water-content in Raw Oil and Manual Electric Dewatering Water-content Test to prove that from the comparison of the time and technical contents of the plaintiff's and defendant's patented technical solution, it can be seen that the defendant has not infringed the plaintiff's patent right.

Evidence B7: Field Operation Test Report for YSL-1 D Tester for water-content in raw oil signed on July 27, 2000 by Yingtai Oil Production Plant Process Research Institute of Petro China Company Limited Jilin Oilfield Branch, and Operation Test Report for YSL-1 D Tester for water-content in raw oil signed on July 27, 2000 by Yingtai Oil Production Plant Oil Production Geology Research Institute of Jilin Petroleum Group Corporation Limited to prove that the defendant had conducted tests for the product before the plaintiff's filing the patent application.

Evidence B8: Certificate Of Approval for accepting the defendant as a member of Daqing Oilfield Suppliers Management System issued on March 9, 2001 by Daqing Petroleum Administration Materials and Equipment Corporation to prove that the defendant's product had been widely used in Daqing before the plaintiff's filing the patent application.

Evidence B9: Field Test Report for YSL-1G Tester for water-content in raw oil signed by the units such as Petro China Daqing Oilfield Company Limited No. 3 Oil Production Plant etc to prove that the defendant's products had been widely used in Daqing before the plaintiff's filing the patent application.

Evidence B10: Inspection Report, the main contents of which include that Quality Supervision and Inspection Center for Petroleum Industry Flow Measuring Instruments inspected on May 30, 2001 the defendant's product YSL-1G Tester for Water-content in Raw Oil to prove that the defendant has not infringed the plaintiff's patent right.

The plaintiff Zhu Guangsheng holds that: he has no objection to the defendant's evidence B1, B2, B3, B4, B5, B8 and B10, but these evidences can not prove that the defendant started to develop and produce the patented technology earlier than the plaintiff, can not prove the defendant's claim that it has not infringed the plaintiff's patent right; the defendant's patent right was granted later than the plaintiff's, so it attributed to a patent right granted repeatedly; the evidence B6 was issued by the defendant itself, so it has no legal effect; the evidence B7 and B9 were obtained by the defendant through illegal means and used the technology belonged to the plaintiff.

Through comprehensive analysis of both parties' defending claims and evidences provided and enquiry opinions, the court confirms that:

I. The plaintiff filed a patent application for Utility Model for "Sensor of automatic wiping water in oil" on July 22, 2000 which was granted on May 2, 2001 a patent right for Utility Model (Patent No. ZL00212739.3). The contents of the claims include: 1. An sensor of automatic wiping water in oil, comprising a lifting mechanism for wiping probe, a circuit for controlling automatic wiping and a sensor for water in oil, characterized in that: the said lifting mechanism for wiping probe comprises a micro motor with deceleration function, a motor base, a support pipe connected with the motor base, a flange connected with the support pipe, a clutch connected with the micro motor, a top screwed connector connected with the clutch via a coupler, a nut connected with the top screwed connector via a thrust bearing, a screwed slider mounted inside the nut with lower hollow part, a micro alnico mounted inside a fixed hole on the screwed slider shell, a upper limit and a lower limit-approach switches mounted at the top and bottom of stripe hole of the support pipe corresponding to the micro alnicos, a bottom screwed connector connected with the screwed slider, a pipe for inner wire protection connected with the bottom screwed connector and passing through the flange, an inner connector connected with the pipe for inner wire protection and the probe respectively, and an oil-wiping sleeve fixed between a protection cover and an outer cover; the said circuit for controlling automatic wiping  comprises an upper limit-approach switch and a lower limit-approach switch, a normal and revere rotation control circuit of motor with an input end connected to the upper and lower limit-approach switches and a circuit with the output end connected to the micro motor and a timing circuit controlling the operation of the micro motor. 2. The sensor of automatic wiping water in oil according to claim 1, characterized in that: the said clutch comprises a connection rod, an outer cover of the clutch connected with the connection rod, a lock sleeve ringing on the connection rod, a friction wheel mounted on the lock sleeve via nuts and connected with the outer cover of the clutch via friction, an adjusting nut connected with the coupler, and a compression spring mounted between the adjusting nut and the outer cover of the clutch.

II. As a salaried employee of the plaintiff's unit during 1997 ¡§C1998, Cai Pengda once borrowed technical documents from the unit, and later he was employed by the defendant's unit.

III. The defendant was established in April 1998. The State Quality Supervision and Inspection Center for Coal Mine Anti-explosion and Safety Products issued on December 4, 1998 the Anti-Explosion Quality Certificate for the defendant's the sensor of YSL-1 D Tester for water-content in raw oil. Jilin Measuring Products (Goods) Quality Supervision and Inspection Station issued in January 1999 the Notice for Prototype Test Results to the defendant. Jilin Technology Supervision Bureau issued in February 1999 the License for Manufacturing Measuring Instruments to allow production of YSL-G and D tester for water-content in raw oil. Changchun Science & Technology Information Net published the propaganda information on the defendant's company and YSL-1G Tester for water-content in raw oil.
 
IV. Yingtai Oil Production Plant Process Research Institute of Petro China Company Limited Jilin Oilfield Branch signed on July 27, 2000 the Field Operation Test Report for YSL-1 D Tester for water-content in raw oil. Yingtai Oil Production Plant Oil Production Geology Research Institute of Jilin Petroleum Group Corporation Limited signed on July 27, 2000 the Operation Test Report for YSL-1 D Tester for water-content in raw oil. The units such as Petro China Daqing Oilfield Company Limited No. 3 Oil Production Plant etc. signed the Field Test Report for YSL-1G Tester for water-content in raw oil.

V. The defendant filed a patent application for Utility Model of "A Kind of High-precise Tester for water-content in raw oil" on November 29, 2000, granted a patent right on October 3, 2001 (Patent No.: ZL00253283.2). The inventors are Cai Pengda and Wangzhimin. The contents of the claims include: 1. A kind of high-precise tester for water-content in raw oil, comprising a main unit and a probe, characterized in that: the probe is fitted with a wiping flake connected to the motor via to-and-fro movement mechanism, and the motor connected to a controller. 2. The tester according to claim 1, characterized in that: the to-and-fro movement mechanism comprises a screw, a nut, a guide post and a wiping rod, the output shaft of the motor passes through a clutch connection rod, the screw is a left-turn and right-turn screw, the nut rings on the screw and fitted with guide post, and the nut connects the wiping flake via the wiping rod.

VI. Daqing Petroleum Administration Materials and Equipment Corporation issued on March 9, 2001 the Certificate of Approval for accepting the defendant as a member of Daqing Oilfield Suppliers Management System.

VII. Quality Supervision and Inspection Center for Petroleum Industry Flow Measuring Instruments inspected on May 30, 2001 the defendant's product YSL-1G Tester for water-content in raw oil.

VIII. The tester for water-content in raw oil produced by the defendant that was charge for patent infringement was sold in Daqing. The tax-excluded unit price of YSL-1D tester for water-content in raw oil is RMB75,846.20.

IX. The defendant's documents such as Product Selection Guideline, Installation and Operation Instructions for YSL-1 D Tester for water-content in raw oil (Wiping Type) etc. introduce the working principle, technical parameters and indices, functions, features, system configuration etc. of the defendant's products; Product Selection Guideline provides the defendant's business license for enterprise as a legal person which was reissued on September 27, 2002; Installation and Operation Instructions for YSL-1 D Tester for water-content in raw oil (Wiping Type) provides at the last page the contact person: Cai Pengda (General Manager).

X. During the court hearing, the defendant admitted that its product that was charged for patent infringement was produced based on the defendant's Utility Model of "A Kind of High-precise Tester for Water-content in Raw Oil".

XI. Entrusted by the plaintiff, Beijing JZSC Intellectual Property Judicature Appraisal Center issued on May 9, 2005 No. Jingjianzi 18616 Appraisal Report. The contents of the report mainly include: the comparative patent involves an "Sensor of automatic wiping water in oil", its independent claim includes the following technical features: A. a power source including a micro motor with deceleration function, a motor base, and a clutch connected with the micro motor; B. a lifting mechanism including a support pipe connected with the motor base, a flange connected with the support pipe, a top screwed connector connected with the clutch via a coupler, a nut connected with the top screwed connector via a thrust bearing, and a screwed slider mounted inside the nut with lower hollow part; C. wiping mechanism including a bottom screwed connector connected with the screwed slider, a pipe for inner wire protection connected with the bottom screwed connector and passing through the flange, an inner connector connected with the pipe for inner wire protection and the probe respectively, and an oil wiping sleeve fixed between a protection cover and an outer cover; D. circuit for controlling automatic wiping  including micro alnico mounted inside the fixed hole on screwed slider shell, an upper limit and a lower limit-approach switches mounted at the top and bottom of the stripe hole of support pipe corresponding to the micro alnicos, a normal and revere rotation control circuit of motor, and a micro motor timing control circuit; E. water-content in oil sensor.

For the compared product, Zhan Jin and Wu Jun from the appraisal center arrived on April 17, 2005 at Daqing Oilfield No. 7 Oil Production Plant, conducted investigation and photo-taking for the in-use high-precise tester for water-content in raw oil mounted on the plant's oil transmission pipeline that is produced by Hongyu Company, and compared and took photos for the duplicate of Hongyu Company's tester for water-content in raw oil provided by the plaintiff and the real object of the tester for water-content in raw oil. The comparison results show that the duplicate is completely consistent with the real object of the high-precise tester for water-content in raw oil produced by Hongyu Company, so it can be used as the compared product in this appraisal to compare with the comparative patent. Hongyu Company's product instructions provide product descriptions and drawings of the high-precise tester for water-content in raw oil. The product descriptions and drawings are completely consistent with the real object of field investigation, so they can be used as references in this appraisal.

The photo and duplicate of the compared product show that the technical features of the compared tester for water-content in raw oil comprises: a. power source, including a micro motor with deceleration function, a motor base, and a clutch connected with the micro motor; b. a lifting mechanism including a support pipe connected with the motor base, a flange connected with the support pipe, bi-directional spiral cylindrical cam connected with the clutch via a coupler, a slider ringing on the bi-directional spiral cylindrical cam and a ship-shaped guide block fitted inside the slider for matching with spiral flute, which fits with the support pipe (guide post) together with the cam slider via one of its U-shaped opening; c. wiping mechanism including two fixed wiping rods fitted on the slider which pass through the flange and are parallel along the pipe for inner wire protection, and the bottom of which connects with wiping flake; d. circuit for controlling automatic wiping  including a photoelectric switch shutter inside the motor base, a limit photoelectric switch fitted on the shutter, a micro motor shutoff control circuit, a micro motor timing control circuit; e. water-content in oil sensor.

Comparison analysis: Power source A and power source a are the same; lifting mechanism B and lifting mechanism b are different; wiping mechanism C and wiping mechanism c are different; circuit for controlling automatic wiping  D and circuit for controlling automatic wiping  d are different; water-content in oil sensor E and water-content in oil sensor e are the same.

The comparison shows that, among 5 technical features of the comparative patent, two of them are the same as those of the compared product and three are different. Since the compared product does not completely reproduce all the technical features as said in the claims of the comparative patent, so it is necessary to conduct equivalent principle when analyzing the 3 different technical features. 

Underlying equivalent principle, comprehensive analysis should be made on the technical features of the compared product uses basically the same means, perform basically the same function and achieve basically the same effect.
1. The technical problem to resolve, function to perform and effect to achieve of the comparative patent.
As shown in paragraph 2 page 1 of the comparative patent's descriptions, the technical problem to resolve is as follows: "Presently, sensors for water in oil used in oilfields and petrochemical industry are directly inserted into the oil transmission pipeline for real-time monitoring water-content in oil. Since oil is dense, wax-contained, membrane-contained, probes can not adequately contact with oil and water, resulting in inaccurate water-content signal and gradually larger error in water-content measurement. Ultimately, the error will exceed the allowable measurement accuracy limit, and long-term accurate, stable and reliable operation of instruments can not be ensured. Therefore, in actual operation, operators have to frequently clean the probes manually. During manual cleaning, it is necessary to reduce pressure and stop oil transmission, then remove the water-content sensor from the pipeline, and wipe it with gasoline, this not only affects the quality of oil product but also increases labor intensity. In addition, such operation is inconvenient, and may possibly result in oil leakage and environmental pollution".
To resolve the abovementioned problem, the comparative patent adopts the following technical solutions: adding an automatic wiping lifting mechanism including a power source, a lifting mechanism, a wiping mechanism and an circuit for controlling automatic wiping in the water-content in oil sensor. The specific configuration is: "a micro motor with deceleration function, a motor base, a support pipe connected with the motor base, a flange connected with the support pipe, a clutch connected with the micro motor, a top screwed connector connected with the clutch via a coupler, a nut connected with the top screwed connector via a thrust bearing, a screwed slider mounted inside the nut with lower hollow part, a micro alnico mounted inside a fixed hole on the screwed slider shell, a upper and a lower limit-approach switches mounted at the top and bottom of stripe hole of the support pipe corresponding to the micro alnicos, a bottom screwed connector connected with the screwed slider, a pipe for inner wire protection connected with the bottom screwed connector and passing through the flange, an inner connector connected with the pipe for inner wire protection and the probe respectively, and an oil wiping sleeve fixed between a protection cover and an outer cover; the said circuit for controlling automatic wiping  comprises an upper and a lower limit-approach switches, a normal and revere rotation control circuit of motor with an input end connected to the upper limit and lower limit-approach switches and an output end connected to the micro motor and a timing circuit controlling the operation of the micro motor".
According to the comparative patent's descriptions, the process of the technical solution indicated from the comparative patent is: the micro motor rotates and drives the top screwed connector and the nut via the clutch, the nut drives the slider to move up, the slider drives the probe to move up via the bottom screwed connector and the pipe for inner wire protection; when the slider rises to the upper limit approach switch, the micro alnico on the slider urges the upper limit approach switch to inhale close so as to send a motor commutating signal to the circuit to control the motor to rotate reversely. Then, the slide drives the probe to move down, when the slide reaches to the lower limit approach switch, the micro alnico urges the lower limit approach switch to inhale close so as to send a motor stopping signal to the circuit to control the motor to stop. This structure is used to achieve the relative movement of the probe and oil wiping sleeve in the water-content in oil sensor. As the sensor realizes to-and-fro movement of the probe in the oil wiping sleeve, the contaminants on the surface of the probe is wiped off, so sensor of automatic wiping water in oil features easy operation and automatic wiping attachments on the surface of the probe without necessity of dismantling. Without affecting oil transmission, it ensures accuracy of measurement, reduces labor intensity and increases automatization level.

The effect the comparative patent has achieved is: to realize periodic cleaning probe, i.e. wiping off surface contaminants of sensor for water-content in oil through the relative movement between the probe and the oil wiping sleeve, ensuring monitor accuracy of sensors for water in oil.
2. Technical problems to be resolved, realized function and achieved effect of the compared product.

As described in Hongyu Company's product instructions for high-precise tester for water-content in raw oil, the problem the compared product wants to resolve is to eliminate deposits on the probe surface so as to increase measurement accuracy and reliability of long-term online monitoring, as raw oil contains a large amount of impurities, such as sand, alkali, wax etc., after sensors operate for a period of time, these impurities will deposit on the probe surface, causing inaccurate water-content monitoring signal and affecting measurement accuracy.

The technical means of the compared product is to add an automatic wiping lifting mechanism comprising a power source, a lifting mechanism, a wiping mechanism, and an circuit for controlling automatic wiping to the sensor for water-content in oil. The specific configuration of the automatic wipe lifting mechanism is: a micro motor with deceleration function, a motor base, a clutch connected with the micro motor, a support pipe connected with the motor base, a flange connected with the support pipe, a photoelectric switch shutter inside the motor base, a limit photoelectric switch fitted on the shutter, a bi-directional spiral cylindrical cam connected with the clutch via a coupler, a slider ringed on the bi-directional spiral cylindrical cam and ship-shaped guide block fitted inside the slider for matching with spiral flute, which matches with the support pipe (guide post) via its U-shaped opening, two fixed wipe rods fitted on slide which pass through the flange and are parallel along pipe for inner wire protection, the bottom of which connects with a wiping flake. The wipe disc closely contacts with the probe surface.

The process of the technical solution of compared product is: the micro motor rotates to drive the bi-directional spiral cylindrical cam via the clutch, the slider moves downwards via its guide block under the function of the bi-directional spiral cylindrical cam with the guide support post as the track; the wiping rod connected with the slide drives the wiping flake to move down along the probe surface; when the nut reaches the bottom of the bi-directional spiral cylindrical cam, the guide block inside the slider automatically slides into reversal thread to drive the wiping flake to move up; when the slider reaches the top of the bi-directional spiral cylindrical cam, the photoelectric switch shutter wards off the lightening hole of the infrared transceiver tube of the limit switch, and sends to the micro motor shutoff signal to the micro motor shutoff controlling circuit to stop the rotation of motor. 

The abovementioned structure shows that the compared product also aims to perform the function and achieve the effect of wiping off the contaminants on the probe surface through relative movement of the probe and the wiping flake of sensor for water-content in oil so as to ensure the monitoring accuracy of the sensor.

3. Comparison analysis on the technical features, functions and effects of the compared product and comparative patent.

(1) Analysis of the comparative patent's technical feature B and the compared product's technical feature b

The bi-directional spiral cylindrical cam mechanism used in the compared product to realize to-and-fro movement belongs to the common knowledge in the relevant fields. No creative work is needed to replace the comparative patent's technical feature of realizing to-and-fro movement via single-way screw bi-directional rotation of lifting mechanism with the technical feature of realizing to-and-fro movement via bi-directional cylindrical cam. Part 32 of Volume 4 of "Mechanism" of Machine Design Handbook (China Machine Press, 2nd Edition, June 2000) introduces concentrated to-and-fro movement mechanisms with illustrations, including to-and-fro bi-directional cylindrical cam mechanism, which is basically the same as the bi-directional cylindrical cam mechanism used in the compared product. Therefore, the comparative patent and the compared product use basically the same technical solution in terms of lifting mechanism to perform the same function and achieve effect of to-and-fro movement. Therefore, the comparative patent's wiping probe lifting mechanism and the compared product's wipe rod mechanism belong to the equivalent technical features.

(2) Analysis of the comparative patent's technical feature C and the compared product's technical feature c

By comparison, their differences in wiping mechanism structure lie in: the comparative patent fixes the oil wiping sleeve between the protection cover and the outer cover, the oil wiping sleeve is fixed, but the probe is moveable; the compared product connects the wiping flake on the wiping rod, the wiping flake moves up and down together with the wiping rod, while the probe is fixed. In term of wipe method, both use relative movement between the oil wiping sleeve (or wiping flake) and the probe to realize wiping of probe surface contaminants, and their technical means, functions and effects are similar, so they belong to the equivalent technical features.

(3) Analysis of the comparative patent's technical feature D and the compared product's technical feature d

The comparative patent and the compared product use the most common switches and relay to control motor to operate, which belongs to the most common knowledge in the relevant fields. Their differences lie in: the comparative patent uses the limit approach switch based on the "magneto-sensitive" principle, it is also the general knowledge in the relevant field to replace magneto-sensitive switches with photoelectric switches, for example, Guideline for Application of New Practical Sensors published by Publishing House of Electronics Industry has introductions on photoelectric switches, while the compared product uses the photoelectric switch to replace the comparative patent's magneto-sensitive switch, these two kinds of switches belong to the same technical means which are used to realize the function and effect of controlling motor shutoff or commutating operation. Therefore the compared product's technical feature of circuit for controlling automatic wiping  and the comparative patent's technical feature of circuit for controlling automatic wiping  fall into the equivalent technical features.

In general, the above mentioned comparison analysis shows that, among the 5 technical features as said in the comparative patent's independent claim, the technical features of the compared product's power source and sensor for water-content in oil are the same as those of the power source and sensor for water-content in oil of the comparative patent; the technical feature of the compared product's wiping rod lifting mechanism is the same as that of the probe lifting mechanism of the comparative patent; the technical feature of the compared product's wiping mechanism is the same as that of the wiping mechanism of the comparative patent; the technical feature of the compared product's circuit for controlling automatic wiping  is the same as that of the circuit for controlling automatic wiping  of the comparative patent; therefore, both use basically the same means to achieve the basically same function and the same effect. Thus, the expert group of this appraisal can come to an unanimous conclusion and accomplish all appraisal items entrusted by the entrusting party. 
 
Appraisal conclusion: the tester for water-content in raw oil falls into the protection scope of Utility Model No. ZL00212739.3.

XII. This institute conducted field investigation and photo-taking on July 5, 2005 for the 5 YSL-1G tester for water-content in raw oil mounted in the oil measuring room of No. 7 Oil Production Plant ¡§C Oil Deposit Site Unite Station of Petro China Daqing Oilfield Company Limited. The products have the technical features such as power source, lifting mechanism, wipe mechanism, automatic wipe control circuit, and sensor for water in oil etc. which are completely consistent with the technical features of the defendant's product affirmed in the Appraisal Report issued by Beijing JZSC Intellectual Property Judicature Appraisal Center; the products are completely consistent with the duplicate of the tester for water-content in raw oil charged for patent infringement provided by the plaintiff.
 
XIII. In the lawsuit, the defendant admitted that Hongyu Company's employee Pu Zhiguo is the director of Daqing Sales Department of Changchun Hongyu Electronic Energy Saving Equipment Development Company Limited. The plaintiff has not found the business license of Daqing Sales Department of Changchun Hongyu Electronic Energy Saving Equipment Development Company Limited, so he withdrew the lawsuit to Daqing Sales Department of Changchun Hongyu Electronic Energy Saving Equipment Development Company Limited.

The dispute this case focuses on whether the tester for water-content in raw oil produced and sold by the defendant infringes on the plaintiff's patent right and how to determine compensation responsibilities.

This court holds that the plaintiff's Utility Model Patent of "Automatic Wipe Water in Oil Sensor" is valid.

First, determining whether the technology used in the alleged patent-infringing product is coved by the existing technology owned by the defendant.
 
The defendant claims that the technology it used is its self-owned existing technology by providing evidence B1, B2, B3, B4, B7 B8, B9 and B10 etc. Although some evidences prove that it had produced the product with the same name as the alleged patent-infringing product before the filing date of the plaintiff's patent application, evidence B1, the defendant's business license, only proves the time of its establishment but can not prove that it had owned the technology; while other evidences do not indicate the specific technical features and complete technical solutions of the technology; the defendant also fails to provide real product and technical data of the product that was produced before the filing date of the plaintiff's patent application. Therefore, the evidences for the defendant's claim that the technology it used is the existing technology it had owned before the filing date of the plaintiff's patent application is insufficient, the court refuses to accept its claim.

Second, determining the evidentiary effect of the Appraisal Report issued by Beijing JZSC Intellectual Property Judicature Appraisal Center.

1. The defendant points out that evidence A2 is the defendant's tester for water-content in raw oil reproduced by the plaintiff, so it can not be used as an evidence.

Beijing JZSC Intellectual Property Judicature Appraisal Center's  personnel arrived on April 17, 2005 at Daqing Oilfield No. 7 Oil Production Plant and conducted field investigation and photo-taking for the in-use high-precise tester for water-content in raw oil mounted on the plant's oil transmission pipeline that was produced by Hongyu Company, and compared and took photos for the duplicate of Hongyu Company's tester for water-content in raw oil provided by the plaintiff and the real object of the tester for water-content in raw oil. The comparison results show that the duplicate is completely consistent with the real object of the high-precise tester for water-content in raw oil produced by Hongyu Company, Hongyu Company's product instructions provide product descriptions and drawings of the high-precise tester for water-content in raw oil. The product descriptions and drawings are completely consistent with the real object of field investigation. This institute conducted field investigation and photo-taking for the YSL-1G tester for water-content in raw oil mounted in the oil measuring room of No. 7 Oil Production Plant ¡§C Oil Deposit Site Unite Station of Petro China Daqing Oilfield Company Limited, and confirmed that the products were completely consistent with the duplicate of the defendant's tester for water-content in raw oil provided by the plaintiff; the products have the technical characteristics of power source, lifting mechanism, wipe mechanism, automatic wipe control circuit etc. and are completely consistent with the technical characteristics of the defendant's product affirmed in the Appraisal Report issued by Beijing JZSC Intellectual Property Judicature Appraisal Center. Therefore, the court accepts the comments regarding "the duplicate is completely consistent with the real object of the high-precise tester for water-content in raw oil produced by Hongyu Company, so it can be used as the compared product in this appraisal to compare with the comparative patent. Hongyu Company's product instructions provide product descriptions and drawings of the high-precise tester for water-content in raw oil. The product descriptions and drawings are completely consistent with the real object of field investigation, so they can be used as references".

2. The defendant points out: the appraisal report was made under the plaintiff's entrustment, so it does not have legal effect.

After complete and strict review of the appraisal by Beijing JZSC Intellectual Property Judicature Appraisal Center, the court affirms that the appraisal by Beijing JZSC Intellectual Property Judicature Appraisal Center is conducted through legal process, the verification documents are authentic, the basis, principle and method of the appraisal is objective, rigorous and professional, and the appraisal conclusion is impartial, accurate, complete and conforming to the relevant laws and regulations, so it shall be accepted by the court. The defendant's defence has no factual evidence, legal basis or counterevidence, so it is untenable, and can not be supported by the court. 

Third, comparison of the alleged patent-infringing product and the plaintiff's patented technology.

1. The alleged patent-infringing product reproduces the 5 technical features of the plaintiff's patent, in which the power source and the sensor for water-content in oil are the same, while the lifting mechanism, the wipe mechanism and the automatic wipe control circuit are different slightly.

2. Equivalent analysis and judgment of different technical features.

(1) Regarding Lifting mechanism, the alleged patent-infringing product uses bi-directional spiral cylindrical cam mechanism to realize to-and-fro movement, which is the common technology in the relevant field. For those skilled in the art, no creative work is needed to replace the comparative patent's technical feature of realizing to-and-fro movement via single-way thread bi-directional rotation of lifting mechanism with the technical feature of realizing to-and-fro movement via bi-directional cylindrical cam.

(2) Regarding wiping mechanism, the alleged patent-infringing product  fixes the oil wiping sleeve between the guard and the cover, the oil wiping sleeve is fixed, but the probe is moveable; the plaintiff's patent connects the wipe flake to the wipe rod, the wipe flake moves up and down together with the wipe rod, while the probe is fixed. In term of wipe method, both use relative movement between oil wiping sleeve (or wipe flake) and probe to realize wiping of probe surface contaminants, and their technical means, functions and effects are similar.
(3) Regarding automatic wipe control circuit, the alleged patent-infringing product uses photoelectric switch to replace magneto-sensitive switch to achieve position limit, which is also a common knowledge in the relevant field. These two kinds of switches belong to the basically same technical means which are used to realize the function and effect of controlling motor shutoff or reversal operation.

3. Comprehensive judgment
The alleged patent-infringing product reproduces the 5 technical features as said in the plaintiff's independent patent claim, in which the power source and the sensor for water-content in oil of the alleged patent-infringing product  are the same as the technical features of the plaintiff's patented technology, while the lifting mechanism, wipe mechanism and automatic wipe control circuit are equivalent to the technical features of the plaintiff's patented technology. Both use basically the same means to realize basically the same function and reach basically the same effect. Therefore, it shall be affirmed that the defendant's tester for water-content in raw oil falls into the protection scope of the plaintiff's patented technology. The defendant's defence that the alleged patent-infringing product is different from the plaintiff's patented technology in principle and structure is untenable, and cannot be accepted by the court.

In addition, the defendant admitted during the court hearing that the defendant's alleged patent-infringing product series was produced based on the Utility Model of "A Kind of High-precise Tester for water-content in raw oil" filed by the defendant in November 2000. The defendant filed the patent application later than the plaintiff's patent application date; both patents belong to the technical solution with the same function, principle and effect under the same subject, so they have noticeable technical continuation relation.

In general, without the plaintiff's permission, the defendant unilaterally used the plaintiff's patented technology to produce the alleged patent infringing products and installed them in Daqing Oilfield, so the defendant's conducts have constituted patent infringement. The defendant shall immediately stop its infringement, and make compensation for the plaintiff's economic losses. As the extent of loss the plaintiff suffered and the extent of benefit the defendant gained are difficult to define, the court defines the amount of compensation to be paid by the defendant according to the specific conditions of this case. The plaintiff's claimed amount is adequate and meets the relevant laws and regulations, so it is supported by the court. The defendant's defence is untenable, so it is not supported by the court. In accordance with the stipulation of Article 11 Section 1 of Patent Law of the People's Republic of China and Article 118 of General Principles of the Civil Law of the People's Republic of China, the judgment is as follows:

I. The defendant Changchun Hongyu Electronic Energy Saving Equipment Development Company Limited shall immediately stop its infringement on the plaintiff Zhu Guangsheng's Utility Model Patent of "Automatic Wipe Water in Oil Sensor" (patent No.: ZL00253283.2.)
 
II. The defendant Changchun Hongyu Electronic Energy Saving Equipment Development Company Limited shall pay a compensation for economic loss of RMB100,000 to the plaintiff Zhu Guangsheng within ten days since the date of the judgment entering into force.
The total court acceptance-fee is RMB3,510, which shall be borne by the defendant Changchun Hongyu Electronic Energy Saving Equipment Development Company Limited.

If not accept this verdict, within 15 days after receiving this judgment, the defendant may present the petition for appeal to this court, and provide duplicates of the petition for appeal according to the number of person in the opposing party to lodge an appeal to Heilongjiang Supreme People's Court. 

Presiding judge: Zheng Guozhi
Acting judge: Liu Haiyan
Acting judge: Chang Yude

Clerk: He Yang