CN213565016U - High-automation textile printing equipment - Google Patents

High-automation textile printing equipment Download PDF

Info

Publication number
CN213565016U
CN213565016U CN202021883670.XU CN202021883670U CN213565016U CN 213565016 U CN213565016 U CN 213565016U CN 202021883670 U CN202021883670 U CN 202021883670U CN 213565016 U CN213565016 U CN 213565016U
Authority
CN
China
Prior art keywords
ink
water
cleaning device
ink jet
textile printing
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.)
Active
Application number
CN202021883670.XU
Other languages
Chinese (zh)
Inventor
李家成
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hebei Hanyue Textile Co ltd
Original Assignee
Hebei Hanyue Textile Co ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Hebei Hanyue Textile Co ltd filed Critical Hebei Hanyue Textile Co ltd
Priority to CN202021883670.XU priority Critical patent/CN213565016U/en
Application granted granted Critical
Publication of CN213565016U publication Critical patent/CN213565016U/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Landscapes

  • Treatment Of Fiber Materials (AREA)
  • Ink Jet (AREA)

Abstract

The utility model discloses a high-automation textile printing device, which comprises a workbench and an ink gun cleaning device, wherein the ink gun cleaning device comprises an ink floating cleaning device and an ink gun cleaning device; the floating ink cleaning device comprises an ink jet device, a bracket group and a cross beam; the bottom surface of the ink jet device is provided with a plurality of ink jet nozzles which are regularly arranged and vertically downward; the ink jet device is connected to the cross beam in a sliding manner; the ink gun cleaning device comprises a water tank, a compressed air injection pipe, a water flow ejector, a connecting pipe and an end cover; one end of the compressed air injection pipe is communicated with the air inlet; an inner cavity is arranged in the water flow ejector; the bottom surface of the water flow ejector is provided with a first through hole; one end of the connecting pipe is communicated with the first through hole, and the other end of the connecting pipe is communicated with the drain hole; the bottom surface of the ink jet device corresponds to the position of the water flow ejector; the ink gun is cleaned through the floating ink cleaning device and the ink gun cleaning device, so that the working efficiency of textile printing is improved, and the maintenance time of equipment is saved.

Description

High-automation textile printing equipment
Technical Field
The utility model relates to a textile printing technical field especially relates to a high automatic textile printing equipment.
Background
The inkjet printing machine has a large amount of vaporific china ink suspension around the shower nozzle in the course of the work, not only influences the jet printing effect, and after vaporific floating ink condenses into the ink droplet, can drop on the printing medium moreover to influence the quality of inkjet printing product, in addition, on suspension part vaporific china ink can the adhesion shower nozzle around the shower nozzle, influence the printing effect of shower nozzle greatly, especially under the higher condition to the printing precision requirement, the influence is bigger. In addition, the ink jet head is blocked in the production process, the machine needs to be stopped for maintenance, the cleaning of the ink jet head is labor-consuming and time-consuming, the ink jet head needs to be disassembled firstly, a manual method is adopted, the cleaning is carried out by a medical injector, and the efficiency is very low.
SUMMERY OF THE UTILITY MODEL
The utility model aims at providing a high automatic weaving stamp equipment to solve the problem that above-mentioned prior art exists, can realize absorbing the ink slick automatically at ink gun operating condition and filter, and dredge the jam of ink gun under the condition that need not dismantle the ink gun.
In order to achieve the above object, the utility model provides a following scheme: the utility model provides a high automatic weaving stamp equipment, including workstation and ink gun belt cleaning device, its characterized in that: the ink gun cleaning device comprises an ink floating cleaning device and an ink gun cleaning device;
preferably, the ink gun is cleaned simultaneously through the floating ink cleaning device and the ink gun cleaning device, and the influence on textile printing due to ink blockage and accumulation is reduced comprehensively.
The floating ink cleaning device comprises an ink jet device, a bracket group and a cross beam; the bottom surface of the ink jet device is provided with a plurality of ink jet nozzles which are regularly arranged and vertically downward; the bracket set includes a first bracket 231 and a second bracket 232; the first bracket is fixedly arranged on one side of the workbench, and the second bracket is arranged on the opposite side surface of the workbench; the support groups are connected through the cross beam; the ink jet device is connected to the cross beam in a sliding manner;
preferably, an ink jet device in the ink floating cleaning device performs repeated reciprocating motion along the beam to print textiles in all directions.
The ink gun cleaning device comprises a water tank, a compressed air injection pipe, a water flow ejector, a connecting pipe and an end cover; the ink gun cleaning device is fixedly connected with the second bracket; the water tank is of a cubic structure, an air inlet hole and a water outlet hole are formed in any side surface of the water tank, and a water inlet hole matched with the end cover is formed in the top surface of the water tank; the end cover is in threaded connection with the water inlet hole; one end of the compressed air injection pipe is communicated with the air inlet hole; an inner cavity is formed in the water flow ejector; the bottom surface of the water flow ejector is provided with a first through hole; one end of the connecting pipe is communicated with the first through hole, and the other end of the connecting pipe is communicated with the drain hole; the bottom surface of the ink jet device corresponds to the position of the water flow ejector.
Preferably, the bottom surface of the ink jet device corresponds to the position of the water flow ejector, and when the ink jet device moves to the position corresponding to the water flow ejector, the water flow ejector carries out water flushing on the butt joint of the ink jet head in the ink jet device, so that dredging is completed, maintenance time is greatly saved, and working efficiency is improved.
The water flow sprayer comprises a water storage tank, a water flow sprayer group and a water spray pipe; an inner cavity is formed in the water storage tank; the top surface of the water storage tank is provided with a second through hole matched with the water flow nozzle group; the water flow nozzle group is communicated with the top surface of the water storage tank through the second through hole; the number of the spray pipes is the same as that of the spray heads of the water flow spray head group, and one end of each spray pipe is fixedly sleeved on each spray head; the water spraying pipe corresponds to the ink gun nozzle.
The preferred adoption rivers shower nozzle group washes by water, has increased rivers pressure by a wide margin, when making rivers wash into the ink jet head among the ink jet set, can dredge more efficiently.
The floating ink cleaning device also comprises an ink absorbing block; the ink absorbing blocks are symmetrically arranged on the ink jet device along two sides of the beam direction; the ink absorbing block is obliquely arranged on the side surface of the ink jet device.
The ink absorption block comprises an ink absorption shell, an air suction fan and an ink filter; ink suction grooves are formed in two side walls of the ink suction shell; the ink suction groove extends outwards along two side walls with different heights and penetrates through the side wall at the top and the side wall at the bottom of the ink suction shell; the suction fan with the china ink filter all set up in inhale the china ink inslot, just the suction fan set up in china ink filter upside.
Preferably, the ink absorbing block sucks all the generated floating ink into the ink absorbing groove through the suction fan, the ink filter completely filters the floating ink, printing pollution caused by the fact that the floating ink is accumulated and dripped on the textile is reduced, and printing error rate is reduced.
The other end of the compressed air injection pipe is sequentially communicated with a pressure gauge and a pressure regulating valve.
Preferably, the air pressure in the cleaning device is led to the inkjet head to the air pressure regulating valve, and accurate regulation and control water jet's pressure improves work efficiency, strengthens the security of mediation in-process.
The distance between the adjacent inner sides of the workbench and the water tank is 0.5-0.8 m; the air inlet and the water outlet are respectively arranged at the upper end and the lower end of the diaphragm 311.
A transverse clapboard is arranged in the middle of the water tank; the diaphragm plate is provided with a plurality of round holes.
The vertical included angle between the ink absorption block and the ink jet device is 45-60 degrees.
Preferably, the floating ink generated by the ink jet device is absorbed and filtered by the ink absorbing block to the maximum extent.
And a pressure release valve is arranged on the top surface of the water tank.
Preferably, the relief valve discharges gas in the water tank, reduces the air pressure in the water tank, is convenient for the end cover to open the water injection, and ensures the safety of the water tank.
The utility model discloses a following technological effect: an ink jet device in the floating ink cleaning device moves repeatedly back and forth along the cross beam to print textiles in all directions; when the ink jet device moves to the position corresponding to the water jet ejector, the water jet ejector flushes the ink gun in the ink jet device in a butt joint mode, so that dredging is completed, maintenance time is greatly saved, and working efficiency is improved; the water flow jet head group is adopted for flushing, so that the water flow pressure is greatly increased, the water flow can be more efficiently dredged when rushing into the ink jet head in the ink jet device, and the success rate of dredging the ink jet head is improved; the ink absorbing block absorbs all the generated floating ink into the ink absorbing groove through the suction fan, and the ink filter completely filters the floating ink, so that printing pollution caused by the fact that the floating ink is accumulated and drops on the textile is reduced, and printing error rate is reduced; the air pressure in the ink gun dredging device is controlled, the pressure of water jet is accurately regulated and controlled, the working efficiency is improved, and the safety in the dredging process is enhanced; the pressure relief valve discharges gas in the water tank, reduces air pressure in the water tank, facilitates opening of the end cover for water injection, and ensures safety of the water tank.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive labor.
Fig. 1 is a schematic structural view of an inkjet head cleaning device according to the present invention.
Fig. 2 is a schematic diagram of the ink absorbing block structure of the present invention.
Fig. 3 is a schematic structural diagram of the present invention.
Fig. 4 is a structural side view of the floating ink cleaning device of the present invention.
Fig. 5 is a top view of the floating ink cleaning device of the present invention.
The device comprises a workbench 1, a floating ink cleaning device 2, an ink jet head cleaning device 3, an ink jet device 21, an ink absorption block 22, a support group 23, a beam 24, an ink absorption shell 221, an air suction fan 222, an ink filter 223, a support 231, a support 232, a water tank 31, a compressed air injection pipe 32, a water flow ejector 33, a connecting pipe 34, an end cover 35, a diaphragm 311, a pressure release valve 312, a pressure gauge 321, a pressure regulating valve 322, a water storage tank 331, a water flow jet head group 332 and a water spray pipe 333.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention is described in detail with reference to the accompanying drawings and the detailed description.
The utility model provides a high automatic weaving stamp equipment, including workstation 1 and ink gun belt cleaning device, its characterized in that: the ink gun cleaning device comprises a floating ink cleaning device 2 and an ink gun cleaning device 3;
the floating ink cleaning device 2 comprises an ink jet device 21, a bracket group 23 and a cross beam 24; the bottom surface of the ink jet device 21 is provided with a plurality of ink jet nozzles which are regularly arranged and vertically downward; the holder set 23 includes a first holder 231 and a second holder 232; a first bracket 231 is fixedly arranged on one side of the workbench 1, and a second bracket 232 is arranged on the opposite side surface of the workbench 1; the bracket group 23 is connected through a cross beam 24; the ink jet device 21 is connected on the cross beam 24 in a sliding way;
the head cleaning device 3 includes a water tank 31, a compressed air injection pipe 32, a water jet ejector 33, a connection pipe 34, and an end cap 35; the inkjet head cleaning device 3 is fixedly connected with the second bracket 232; the water tank 31 is of a cubic structure, and is provided with an air inlet hole and a water outlet hole on any side surface, and a water inlet hole matched with the end cover 35 on the top surface; the end cover 35 is in threaded connection with the water inlet hole; one end of the compressed air injection pipe 32 is communicated with the air inlet hole; an inner cavity is arranged in the water flow ejector 33; the bottom surface of the water flow ejector 33 is provided with a first through hole; one end of the connecting pipe 34 is communicated with the first through hole, and the other end is communicated with the drain hole; the bottom surface of the ink jet device 21 corresponds to the position of the water jet ejector 33.
The water jet ejector 33 includes a water storage tank 331, a water jet head set 332 and a water jet pipe 333; an inner cavity is formed in the water storage tank 331; the top surface of the water storage tank 331 is provided with a second through hole matched with the water flow nozzle group 332; the water flow nozzle set 332 is communicated with the top surface of the water storage tank 331 through a second through hole; the number of the spray pipes 333 is the same as that of the water flow spray head group 332, and one end of each spray pipe 333 is fixedly sleeved on each spray head; the water jet pipe 333 corresponds to the position of the nozzle.
The floating ink cleaning device 2 further includes an ink suction block 22; the ink jet device 21 is symmetrically provided with ink absorption blocks 22 along the two sides of the beam 24; the ink absorbing block 22 is provided obliquely to the side of the ink jet device 21.
The ink suction block 22 includes an ink suction housing 221, a suction fan 222, and an ink filter 223; ink suction grooves are formed in two side walls of the ink suction shell 221; the ink suction grooves extend outwards along two side walls with different heights and penetrate through the top side wall and the bottom side wall of the ink suction shell 221; the suction fan 222 and the ink filter 223 are disposed in the ink suction groove, and the suction fan 222 is disposed on the upper side of the ink filter 23.
The other end of the compressed air injection pipe 32 is connected to a pressure gauge 321 and a pressure regulating valve 322 in this order.
The distance between the adjacent inner sides of the workbench 1 and the water tank 31 is 0.5-0.8 m.
A transverse partition plate 311 is horizontally arranged in the middle of the water tank 31; the diaphragm 311 is provided with a plurality of round holes; the air inlet and the water outlet are respectively arranged at the upper end and the lower end of the diaphragm 311.
The vertical included angle between the ink absorption block 22 and the ink jet device 21 is 45-60 degrees.
The top surface of the water tank 31 is provided with a relief valve 312.
In an embodiment of the present invention, during the process of jetting ink to the textile by the inkjet device 21, the generated ink floating in the opposite direction is sucked by the ink absorbing blocks 22 disposed at both sides of the inkjet device 21 and filtered by the ink filter 223 in the ink absorbing block 22.
In another embodiment of the present invention, the ink jet device 21 is moved above the ink jet cleaning device 3 so that the water jet pipe 333 corresponds to the nozzle position, and the water jet pipe 333 jets water to the nozzle to break the ink clogging.
The utility model discloses a following technological effect: the utility model discloses a following technological effect: an ink jet device in the floating ink cleaning device moves repeatedly back and forth along the cross beam to print textiles in all directions; when the ink jet device moves to the position corresponding to the water jet ejector, the water jet ejector flushes the ink gun in the ink jet device in a butt joint mode, so that dredging is completed, maintenance time is greatly saved, and working efficiency is improved; the water flow jet head group is adopted for flushing, so that the water flow pressure is greatly increased, the water flow can be more efficiently dredged when rushing into the ink jet head in the ink jet device, and the success rate of dredging the ink jet head is improved; the ink absorbing block absorbs all the generated floating ink into the ink absorbing groove through the suction fan, and the ink filter completely filters the floating ink, so that printing pollution caused by the fact that the floating ink is accumulated and drops on the textile is reduced, and printing error rate is reduced; the air pressure in the ink gun dredging device is controlled, the pressure of water jet is accurately regulated and controlled, the working efficiency is improved, and the safety in the dredging process is enhanced; the pressure relief valve discharges gas in the water tank, reduces air pressure in the water tank, facilitates opening of the end cover for water injection, and ensures safety of the water tank.
In the description of the present invention, it is to be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are merely for convenience of description of the present invention, and do not indicate or imply that the device or element so referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore, should not be construed as limiting the present invention.
The above-mentioned embodiments are only intended to describe the preferred embodiments of the present invention, but not to limit the scope of the present invention, and those skilled in the art should also be able to make various modifications and improvements to the technical solution of the present invention without departing from the spirit of the present invention, and all such modifications and improvements are intended to fall within the scope of the present invention as defined in the appended claims.

Claims (9)

1. The utility model provides a textile printing equipment of high automation, includes workstation (1) and ink gun belt cleaning device, its characterized in that: the ink gun cleaning device comprises an ink floating cleaning device (2) and an ink gun cleaning device (3);
the floating ink cleaning device (2) comprises an ink jet device (21), a bracket group (23) and a cross beam (24); the bottom surface of the ink jet device (21) is provided with a plurality of ink jet nozzles which are regularly arranged and vertically downward; the bracket set (23) comprises a first bracket (231) and a second bracket (232); the first bracket (231) is fixedly installed on one side of the workbench (1), and the second bracket (232) is arranged on the opposite side surface of the workbench (1); the support groups (23) are connected through the cross beam (24); the ink jet device (21) is connected to the cross beam (24) in a sliding manner;
the ink gun cleaning device (3) comprises a water tank (31), a compressed air injection pipe (32), a water flow ejector (33), a connecting pipe (34) and an end cover (35); the ink gun cleaning device (3) is fixedly connected with the second bracket (232); the water tank (31) is of a cubic structure, an air inlet hole and a water drain hole are formed in any side surface of the water tank, and a water inlet hole matched with the end cover (35) is formed in the top surface of the water tank; the end cover (35) is in threaded connection with the water inlet hole; one end of the compressed air injection pipe (32) is communicated with the air inlet hole; an inner cavity is formed in the water flow ejector (33); the bottom surface of the water flow ejector (33) is provided with a first through hole; one end of the connecting pipe (34) is communicated with the first through hole, and the other end of the connecting pipe is communicated with the drain hole; the bottom surface of the ink jet device (21) corresponds to the position of the water jet ejector (33).
2. A highly automated textile printing apparatus according to claim 1, wherein: the water jet ejector (33) comprises a water storage tank (331), a water jet nozzle group (332) and a water jet pipe (333); an inner cavity is formed in the water storage tank (331); the top surface of the water storage tank (331) is provided with a second through hole matched with the water flow nozzle group (332); the water flow nozzle group (332) is communicated with the top surface of the water storage tank (331) through the second through hole; the number of the spray pipes (333) is the same as that of the spray heads of the water flow spray head group (332), and one end of each spray pipe (333) is fixedly sleeved on each spray head; the water spray pipe (333) corresponds to the position of the ink jet nozzle.
3. A highly automated textile printing apparatus according to claim 1, wherein: the floating ink cleaning device (2) also comprises an ink absorbing block (22); the ink absorbing blocks (22) are symmetrically arranged on the two sides of the ink jet device (21) along the direction of the cross beam (24); the ink absorbing block (22) is obliquely arranged on the side surface of the ink jet device (21).
4. A highly automated textile printing apparatus according to claim 3, wherein: the ink absorption block (22) comprises an ink absorption shell (221), a suction fan (222) and an ink filter (223); ink suction grooves are formed in two side walls of the ink suction shell (221); the ink suction groove extends outwards along two side walls with different heights and extends through the side wall at the top and the side wall at the bottom of the ink suction shell (221); the suction fan (222) and the ink filter (223) are arranged in the ink suction groove, and the suction fan (222) is arranged on the upper side of the ink filter (223).
5. A highly automated textile printing apparatus according to claim 1, wherein: the other end of the compressed air injection pipe (32) is communicated with a pressure gauge (321) and a pressure regulating valve (322) in sequence.
6. A highly automated textile printing apparatus according to claim 1, wherein: the distance between the adjacent inner sides of the workbench (1) and the water tank (31) is 0.5-0.8 m.
7. A highly automated textile printing apparatus according to claim 1, wherein: a transverse clapboard (311) is horizontally arranged in the middle of the water tank (31); the transverse partition plate (311) is provided with a plurality of round holes; the air inlet hole and the water drain hole are respectively arranged at the upper end and the lower end of the diaphragm plate (311).
8. A highly automated textile printing apparatus according to claim 3, wherein: the vertical included angle between the ink absorption block (22) and the ink jet device (21) is 45-60 degrees.
9. A highly automated textile printing apparatus according to claim 1, wherein: a pressure relief valve (312) is arranged on the top surface of the water tank (31).
CN202021883670.XU 2020-09-02 2020-09-02 High-automation textile printing equipment Active CN213565016U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202021883670.XU CN213565016U (en) 2020-09-02 2020-09-02 High-automation textile printing equipment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202021883670.XU CN213565016U (en) 2020-09-02 2020-09-02 High-automation textile printing equipment

Publications (1)

Publication Number Publication Date
CN213565016U true CN213565016U (en) 2021-06-29

Family

ID=76569097

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202021883670.XU Active CN213565016U (en) 2020-09-02 2020-09-02 High-automation textile printing equipment

Country Status (1)

Country Link
CN (1) CN213565016U (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115570888A (en) * 2022-10-14 2023-01-06 郭森 Polarizing plate jet printing manufacturing equipment

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115570888A (en) * 2022-10-14 2023-01-06 郭森 Polarizing plate jet printing manufacturing equipment
CN115570888B (en) * 2022-10-14 2024-05-03 郭森 Polarizing plate spray printing manufacturing equipment

Similar Documents

Publication Publication Date Title
CN206589464U (en) A kind of ink jet head cleaner
CN213565016U (en) High-automation textile printing equipment
CN110861300A (en) High-resolution printing device and printing equipment
CN211516309U (en) Vertical lifting table milling machine for high-precision machining of gears
JP4789476B2 (en) Ink viscosity adjusting device and printing machine
CN210847391U (en) Servo dragging type spray cleaning machine
CN113733754B (en) Printing nozzle maintenance device
CN113733755B (en) Printing nozzle ink suction device
CN209094023U (en) The dedicated cleaner of droplet ejection 3D printing head
CN211542899U (en) Industrial jet printing equipment
CN210206309U (en) Digit control machine tool that dust removal effect is good
CN114872444A (en) Inkjet printer with function of moisturizing nozzles
CN211542908U (en) Ink jet head cleaning device of jet printing equipment
CN211542912U (en) Ink supply system of ink jet head of jet printing equipment
CN109290258B (en) Special cleaning device and cleaning method for droplet jetting 3D printing head
CN210082681U (en) Inside belt cleaning device of digital ink jet printer ink gun of high temperature glass
CN114016320B (en) Paper machine dry net cleaning assembly and equipment based on high-pressure back flushing
CN216040408U (en) Paper machine dry net cleaning head assembly and equipment capable of preventing water mist from overflowing
CN111871105A (en) High-efficient dust removal cabinet
CN209344032U (en) A kind of Etaching device improving lead frame machining accuracy
CN216170371U (en) Polyvinyl acetate emulsion filter equipment
CN220095967U (en) Pipeline cleaning device of printing ink jet numbering machine
CN111805432B (en) Non-blocking dust removal cabinet for stone processing
CN220332292U (en) Cleaning device for cleaning printer nozzle
CN215751446U (en) Nozzle moving device for high-speed digital rotary printing

Legal Events

Date Code Title Description
GR01 Patent grant
GR01 Patent grant
EE01 Entry into force of recordation of patent licensing contract

Assignee: Hebei Huazhi Xinrong Home Textile Co.,Ltd.

Assignor: Hebei hanyue Textile Co.,Ltd.

Contract record no.: X2023980037132

Denomination of utility model: A highly automated textile printing equipment

Granted publication date: 20210629

License type: Common License

Record date: 20230627

Assignee: Hebei Huazhi Xinrong Home Textile Co.,Ltd.

Assignor: Hebei hanyue Textile Co.,Ltd.

Contract record no.: X2023980037221

Denomination of utility model: A highly automated textile printing equipment

Granted publication date: 20210629

License type: Common License

Record date: 20230628

EE01 Entry into force of recordation of patent licensing contract