CN105982583B - Food processor and anti-stalling method thereof - Google Patents

Food processor and anti-stalling method thereof Download PDF

Info

Publication number
CN105982583B
CN105982583B CN201510050559.XA CN201510050559A CN105982583B CN 105982583 B CN105982583 B CN 105982583B CN 201510050559 A CN201510050559 A CN 201510050559A CN 105982583 B CN105982583 B CN 105982583B
Authority
CN
China
Prior art keywords
motor
load current
voltage
dismembyator
food
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
CN201510050559.XA
Other languages
Chinese (zh)
Other versions
CN105982583A (en
Inventor
代松
何剑萍
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.)
Zhejiang Shaoxing Supor Domestic Electrical Appliance Co Ltd
Original Assignee
Zhejiang Shaoxing Supor Domestic Electrical Appliance 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 Zhejiang Shaoxing Supor Domestic Electrical Appliance Co Ltd filed Critical Zhejiang Shaoxing Supor Domestic Electrical Appliance Co Ltd
Priority to CN201510050559.XA priority Critical patent/CN105982583B/en
Publication of CN105982583A publication Critical patent/CN105982583A/en
Application granted granted Critical
Publication of CN105982583B publication Critical patent/CN105982583B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Landscapes

  • Food-Manufacturing Devices (AREA)
  • Cookers (AREA)

Abstract

The invention provides an anti-stalling method of a food processor, which comprises the following steps: a. powering on a motor to drive a grinder to rotate along a first direction and grind food materials; b. detecting a load current/voltage of the motor; c. judging whether the detected load current/voltage is greater than or equal to a preset value; d. if the detected load current/voltage is larger than or equal to the preset value, pausing the motor and boiling and/or soaking the food material for preset time. In addition, the invention also provides a food processor suitable for applying the anti-stalling method.

Description

Food cooking machine and its anti-blocking shifting method
Technical field
The invention belongs to kitchen small household appliances fields, and in particular to a kind of food cooking machine and its anti-blocking shifting method.
Background technique
Soy bean milk making machine is widely used by people.For food cooking machine crashing food with its slow-speed of revolution, low noise etc. is related more The advantages of, the new direction of lower step soy bean milk making machine development will be become.From current soy bean milk making machine in grinding cooking cycle, discovery is hard because of food Degree relationship, fruit-vegetable fibre is excessively thick or stripping and slicing is excessive, is possible to generate the case where load is greater than motor rated power, easily makes motor Stall, to burn motor or damage transmission mechanism.There is not the technology of relevant blocking rotation also from known soy bean milk making machine, looks into Looking on related anti-blocking technology juice extractor has: method one was being loaded by the way that clutch structure is arranged on the transmission device of juice extractor When big, motor block-proof is realized;Forward-reverse switch is arranged on juice extractor product in method two, when finding motor rotation blockage, controls by hand The food of discharge blocking is realized in positive and negative rotation processed, releases motor rotation blockage state.
Although both the above technology has reached protection motor, the purpose of blocking rotation, but still have more deficiency: method one exists It after starting protection, needs to start to reinstall, restoring clutch structure can just reuse, this brings greatly not to user Just;Method two wants someone to keep side in product use process, finds motor rotation blockage, it is necessary to which operation could be solved effectively by hand The problem of except motor rotation blockage, soy bean milk making machine when in use, be all starting after it is unattended, in this way there is no thoroughly solution stall it is hidden Suffer from.
Summary of the invention
For the above-mentioned problems in the prior art, the present invention provides a kind of food cooking machine and its blocking rotation sides Method.
According to an aspect of the invention, there is provided a kind of anti-blocking shifting method of food cooking machine, comprising:
A. it is powered on to motor, to drive dismembyator to be rotated in a first direction, grind food materials;
B. load current/voltage of the motor is detected;
C. judge whether the load current/voltage detected is greater than or equal to predetermined value;
D. if the load current/voltage detected is greater than or equal to the predetermined value, suspend the motor and by the food materials Infusion and/or immersion predetermined time.
Preferably, step d further comprises in the anti-blocking shifting method of above-mentioned food cooking machine: by the food materials Infusion and/or after impregnating the predetermined time, rotates the motor driven dismembyator along the first direction or second direction, In the second direction it is opposite with the first direction.
Preferably, step d further comprises in the anti-blocking shifting method of above-mentioned food cooking machine:
D1. will the food materials infusion and/or impregnate the predetermined time before, make the motor driven dismembyator along with this first Contrary second direction rotation, while detecting load current/voltage of the motor and judging the load current/electricity detected Whether pressure is greater than or equal to predetermined value;
D2. when the load current/voltage detected is greater than or equal to the predetermined value again, step b~step is repeated Rapid c;
D3. when n-th detects that the load current/voltage is greater than or equal to predetermined value, suspend the motor and by the food Material infusion and/or immersion predetermined time, wherein N is positive integer.
Preferably, further comprising in the anti-blocking shifting method of above-mentioned food cooking machine:
E. if the load current/voltage detected is less than the predetermined value, continue to rotate the grinding along the first direction Device.
Preferably, the infusion is by the food heating to predetermined temperature in the anti-blocking shifting method of above-mentioned food cooking machine Degree.
According to another aspect of the present invention, a kind of food cooking machine is provided, comprising:
Cup body is suitable for accommodating food materials;
Dismembyator is set in the cup body;
Motor, suitable for driving the dismembyator to rotate along first direction or the second direction opposite with the first direction, with Grind this glass of intracorporal food materials;
Detection unit detects load current/voltage of the motor;
Controller is connect with the motor and detection unit signal,
Wherein, when the motor driven dismembyator is rotated in a first direction, which detects the load of the motor Current/voltage, and by output to the controller;Whether load current/voltage that controller judgement detects is greater than or waits In predetermined value;And if the load current/voltage detected is greater than or equal to the predetermined value, which suspends the motor simultaneously By the food materials infusion and/or impregnate the predetermined time.
Preferably, after it the food materials infusion and/or the predetermined time will be impregnated, making this in above-mentioned food cooking machine The motor driven dismembyator is rotated along the first direction or second direction, and wherein the second direction is opposite with the first direction.
Preferably, by before the food materials infusion and/or impregnating the predetermined time, making this in above-mentioned food cooking machine The motor driven dismembyator is rotated along the second direction opposite with the first direction, while detecting load current/electricity of the motor It presses and judges whether the load current/voltage detected is greater than or equal to predetermined value;It repeats when the load current/voltage detected Change the direction of rotation of the dismembyator when more than or equal to the predetermined value;And detect that the load current/voltage is big in n-th In or be equal to predetermined value when, suspend the motor and by the food materials infusion and/or impregnate the predetermined time, wherein N be positive integer.
Preferably, in above-mentioned food cooking machine, if the load current/voltage detected is less than the predetermined value, Continue to rotate the dismembyator along the first direction.
Preferably, above-mentioned infusion can be the food heating a to predetermined temperature in above-mentioned food cooking machine.
Compared with prior art, the beneficial effect of food cooking machine of the invention and its anti-blocking shifting method is mainly shown as:
1, automatic block-resistant is realized by current detecting, improves security performance;
2, stall number is reduced, electrical machinery life is extended;
3, it is ground again after food materials softening, culinary art effect is more preferable, and particle is smaller.
It should be appreciated that the general description and the following detailed description more than present invention be all it is exemplary and illustrative, And it is intended that the present invention as claimed in claim provides further explanation.
Detailed description of the invention
It is to provide further understanding of the invention including attached drawing, they are included and constitute part of this application, Attached drawing shows the embodiment of the present invention, and plays the role of explaining the principle of the invention together with this specification.In attached drawing:
Fig. 1 shows the flow chart of first embodiment according to the present invention.
Fig. 2 shows the flow charts of second embodiment according to the present invention.
Fig. 3 shows the flow chart of third embodiment according to the present invention.
Fig. 4 shows the schematic structure for being suitble to the food cooking machine of application anti-blocking shifting method of the invention.
Specific embodiment
The embodiment of the present invention is described with detailed reference to attached drawing now.Now with detailed reference to preferred implementation of the invention Example, its example is shown in the drawings.Although term used in the present invention is selected from public term, Some terms mentioned in description of the invention may be that applicant is judged to carry out selection as his or her, and detailed meanings exist Illustrate in the relevant portion of description herein.Furthermore, it is desirable that not only by used actual terms, and be also to by every Meaning that a term is contained understands the present invention.
Fig. 1 shows the flow chart of first embodiment according to the present invention.If Fig. 1 is somebody's turn to do, the food cooking machine of the embodiment Anti-blocking shifting method 100 mainly comprise the steps that
Firstly, (step 101) is powered on to motor, to drive dismembyator to be rotated in a first direction (step 102), grinding food Material.For example, the first direction can be direction clockwise or counter-clockwise.
Then, load current/voltage (step 103) of the motor is detected.
Judge whether the load current/voltage detected is greater than or equal to predetermined value (step 104).Generally, motor is negative It carries current/voltage and means that be in the presence of that food materials block dismembyator more than or equal to predetermined value.Accordingly, it is possible to by anti- Turn the mode of (direction of rotation of change dismembyator) the food materials of blocking are discharged, so that dismembyator restores to work normally.
But when stall occurs if it is really up to the mark due to food, motor reversal can't change the hardness of food, therefore can Stall can still be will form, so as to cause multiple reversion, the repeat impact to motor is caused, motor and circuit may finally be will affect Service life.Therefore, present invention further contemplates the methods softened to food, if devising the load detected Current/voltage is greater than or equal to the predetermined value, then suspends the motor (step 105) and make a reservation for the food materials infusion and/or immersion Time (step 106), until completing preset milling time.For example, the infusion be by the food heating to predetermined temperature, such as By food heating and it is maintained at 90 DEG C or more of the state of temperature and is known as infusion.Certainly, the present invention is not intended to limit specific infusion The range of temperature, the infusion temperature can be set or be adjusted according to the actual needs of culinary art.Compared with prior art, The present invention can make food materials soften by prolonged infusion and/or immersion, to reduce the number of stall, extend food material The service life of reason machine.
In addition, as an example, if the load current/voltage detected is less than the predetermined value, can continue Continue to rotate the dismembyator along above-mentioned first direction, until completing entire preset milling time.For example, the milling time is It is set according to specific food materials or culinary art demand.
Fig. 2 shows the second embodiments of the anti-blocking shifting method of food cooking machine according to the present invention.The second embodiment Essentially identical with step 101~106 of the above-mentioned first embodiment therefore identical step of step 201~step 206 no longer add To repeat.The second embodiment is essentially consisted in the difference of above-mentioned first embodiment: in the infusion and/or immersion for carrying out food materials After the step 206 of predetermined time, which, which further comprises, makes the motor driven dismembyator along the first party (step 207) is rotated to or with the opposite second direction of the first direction, until completing preset entire milling time, is completed Grinding.
The 3rd embodiment of the anti-blocking shifting method of food cooking machine according to the present invention is shown turning now to Fig. 3, Fig. 3. The step 301 of the 3rd embodiment~304 are essentially identical with step 101~104 of above-mentioned first embodiment, therefore these phases Same step is not repeated here.The 3rd embodiment is essentially consisted in the difference of above-mentioned first embodiment:
Will the food materials infusion and/or impregnate the predetermined time before, it is also necessary to judgement detect that the load current/voltage is big In or equal to the number of predetermined value whether be more than preset N (N is positive integer) (step 305).If number is less than N, Change the direction of rotation of dismembyator, such as revolves the motor driven dismembyator along the second direction opposite with the first direction Turn, while detecting load current/voltage of the motor and to judge whether load current/voltage for detecting is greater than or equal to predetermined Value (repeats step 303 to step 304).And it is predetermined to detect that the load current/voltage is greater than or equal in n-th When value, then suspend the motor and by the food materials infusion and/or impregnate predetermined time (step 306).
Fig. 4 shows the schematic explosive view for being suitble to the food cooking machine 100 of application anti-blocking shifting method of the invention.Such as figure Shown in 1, food cooking machine 100 generally includes cup lid I, cup body II and pedestal III.Cup body II is suitable for accommodating food materials.Specifically Ground, food cooking machine 100 further include the dismembyator 101 being set in cup body II.Dismembyator 101 and upper coupling 103 pass through axis The coupling of 102 phase of bar.Lower coupler 104 and motor 105 can be equipped in pedestal III.Lower coupler 104 is fixed on the defeated of motor 105 In outlet, so as to be rotated under the drive of motor 105 so that motor 105 drive the dismembyator 101 along first direction (such as Clockwise) or the second direction opposite with the first direction (such as counter clockwise direction) rotates, to grind in the cup body Food materials.
The bottom of cup body II is equipped with aperture, when assembling dismembyator 101 is ground, dismembyator 101 can be passed through cup body The aperture of the bottom of II engages upper coupling 103 with lower coupler 104.Upper coupling 103 can pass through lower coupler as a result, 104 rotation and be driven to rotate, and then upper coupling 103 can drive shaft 102 rotate.Shaft 102 is fixed in dismembyator 101 Internal dynamic mill part (not shown), so as to drive the dynamic mill part rotation.Dynamic mill part inside dismembyator 102 moves mill with this is covered on The relative motion between fine grinding component outside part, realizes grinding function.
In addition, the food cooking machine 100 can also include the load current/voltage detection unit for detecting the motor 105 (not shown) and the controller (not shown) being connect with the motor 105 and detection unit signal, so as to implement the present invention Above-mentioned anti-blocking shifting method.
In particular, the food cooking machine is suitable for the application of above-mentioned anti-blocking shifting method of the invention.
For example, according to a kind of embodiment, when the motor 105 drives the dismembyator 101 to be rotated in a first direction, the inspection Survey unit and detect load current/voltage of the motor 105, and by output to the controller;Controller judgement detects Whether load current/voltage is greater than or equal to predetermined value;And if the load current/voltage detected is predetermined more than or equal to this Value, then the controller suspend the motor 105 and by the food materials infusion and/or impregnate the predetermined time.
Alternatively, another embodiment according to shown in figure 2 above, it can be pre- periodically by the food materials infusion and/or immersion Between after, make the motor 105 that the dismembyator 101 be driven to rotate along the first direction or second direction, wherein the second direction It is opposite with the first direction.
Alternatively, the another embodiment according to shown in figure 3 above, it can also be predetermined by the food materials infusion and/or immersion Before time, makes the motor 105 that the dismembyator 101 be driven to rotate along the second direction opposite with the first direction, detect simultaneously Load current/voltage of the motor 105 simultaneously judges whether the load current/voltage detected is greater than or equal to predetermined value;It repeats Change the direction of rotation of the dismembyator 101 when the load current/voltage detected is greater than or equal to the predetermined value;And When n times detect that the load current/voltage is greater than or equal to predetermined value, suspend the motor 105 and by the food materials infusion and/or leaching The predetermined time is steeped, wherein N is positive integer.
Food cooking machine of the invention and its anti-blocking shifting method can realize automatic block-resistant by current detecting, improve safety Performance;Stall number is reduced, electrical machinery life is extended.In addition, technology of the invention is ground again after softening food materials, effect is cooked More preferably, particle is smaller.
Those skilled in the art can be obvious, the above exemplary embodiments of the invention can be carry out various modifications and modification and Without departing from the spirit and scope of the present invention.Accordingly, it is intended to which present invention covering is made to fall in the appended claims and its equivalence techniques Modifications of the present invention and modification in aspects.

Claims (10)

1. a kind of anti-blocking shifting method of food cooking machine, comprising:
A. it is powered on to motor, to drive dismembyator to be rotated in a first direction, grind food materials;
B. load current/voltage of the motor is detected;
C. judge whether the load current/voltage detected is greater than or equal to predetermined value;
D. if the load current/voltage detected is greater than or equal to the predetermined value, suspend the motor and by the food Material infusion and/or immersion predetermined time.
2. the anti-blocking shifting method of food cooking machine as described in claim 1, which is characterized in that the step d further comprises: After it the food materials infusion and/or the predetermined time will be impregnated, make dismembyator described in the motor driven along the first direction Or second direction rotation, wherein the second direction is opposite to the first direction.
3. the anti-blocking shifting method of food cooking machine as described in claim 1, which is characterized in that the step d further comprises:
D1. will the food materials infusion and/or impregnate the predetermined time before, make dismembyator described in the motor driven along with it is described The opposite second direction rotation of first direction, while detecting load current/voltage of the motor and judging the load detected Whether current/voltage is greater than or equal to predetermined value;
D2. when the load current/voltage detected is greater than or equal to the predetermined value again, change the rotation side of dismembyator To simultaneously repeating said steps b~step c;
D3. when n-th detects that the load current/voltage is greater than or equal to predetermined value, suspend the motor and will be described Food materials infusion and/or immersion predetermined time, wherein N is positive integer.
4. the anti-blocking shifting method of food cooking machine as described in claim 1, which is characterized in that further comprise:
E. if the load current/voltage detected be less than the predetermined value, continue along the first direction rotation described in grind Grinder.
5. the anti-blocking shifting method of food cooking machine as described in claim 1, which is characterized in that the infusion is by the food materials It is heated to predetermined temperature.
6. a kind of food cooking machine, comprising:
Cup body is suitable for accommodating food materials;
Dismembyator is set in the cup body;
Motor, suitable for driving the dismembyator to rotate along first direction or second direction opposite to the first direction, with Grind the intracorporal food materials of the cup;
Detection unit detects load current/voltage of the motor;
Controller is connect with the motor and detection unit signal,
Wherein, when the dismembyator described in the motor driven is rotated in a first direction, the detection unit detects the motor Load current/voltage, and by output to the controller;Whether load current/voltage that the controller judgement detects More than or equal to predetermined value;And if the load current/voltage detected is greater than or equal to the predetermined value, the controller Suspend the motor and by the food materials infusion and/or impregnate the predetermined time.
7. food cooking machine as claimed in claim 6, which is characterized in that the food materials infusion and/or immersion is pre- periodically Between after, rotate dismembyator described in the motor driven along the first direction or second direction, wherein the second party To opposite to the first direction.
8. food cooking machine as claimed in claim 6, which is characterized in that the food materials infusion and/or immersion is pre- periodically Between before, rotate dismembyator described in the motor driven along second direction opposite to the first direction, while detecting institute It states load current/voltage of motor and judges whether the load current/voltage detected is greater than or equal to predetermined value;It repeats when inspection Load current/the voltage measured changes the direction of rotation of the dismembyator when being greater than or equal to the predetermined value;And in n-th When detecting that the load current/voltage is greater than or equal to predetermined value, suspend the motor and by the food materials infusion and/or leaching The predetermined time is steeped, wherein N is positive integer.
9. food cooking machine as claimed in claim 6, which is characterized in that if the load current/voltage detected is less than institute Predetermined value is stated, then continues to rotate the dismembyator along the first direction.
10. food cooking machine as claimed in claim 6, which is characterized in that the infusion is by the food heating to predetermined Temperature.
CN201510050559.XA 2015-01-30 2015-01-30 Food processor and anti-stalling method thereof Active CN105982583B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201510050559.XA CN105982583B (en) 2015-01-30 2015-01-30 Food processor and anti-stalling method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201510050559.XA CN105982583B (en) 2015-01-30 2015-01-30 Food processor and anti-stalling method thereof

Publications (2)

Publication Number Publication Date
CN105982583A CN105982583A (en) 2016-10-05
CN105982583B true CN105982583B (en) 2018-12-07

Family

ID=57035442

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201510050559.XA Active CN105982583B (en) 2015-01-30 2015-01-30 Food processor and anti-stalling method thereof

Country Status (1)

Country Link
CN (1) CN105982583B (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108013719A (en) * 2016-11-02 2018-05-11 广东美的生活电器制造有限公司 A kind of food processor
CN108497952A (en) * 2017-02-23 2018-09-07 广东美的生活电器制造有限公司 Food cooking machine and its anti-blocking rotary device, method
CN107479457B (en) * 2017-05-18 2020-04-07 浙江绍兴苏泊尔生活电器有限公司 Food processor and control method thereof
CN109222691B (en) * 2018-09-29 2021-08-03 九阳股份有限公司 Crushing degree detection method of food processing machine
CN111121860B (en) * 2018-10-31 2022-05-17 佛山市顺德区美的电热电器制造有限公司 Operation control method and device of blanking motor, cooking utensil and storage medium
CN112568738A (en) * 2019-09-27 2021-03-30 美的威灵电机技术(上海)有限公司 Food processor, control method and computer-readable storage medium
CN111084535B (en) * 2019-12-20 2021-04-13 珠海格力电器股份有限公司 Food mixer control method and device, storage medium and food mixer
CN112426055A (en) * 2020-10-30 2021-03-02 添可智能科技有限公司 Control method of slice assembly

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102273934A (en) * 2011-05-27 2011-12-14 浙江绍兴苏泊尔生活电器有限公司 Multifunctional operation mode grinding soybean milk machine and speed-regulating grinding method thereof
CN102327062A (en) * 2011-07-30 2012-01-25 浙江绍兴苏泊尔生活电器有限公司 Grinding soybean milk machine and anti-stalling method thereof
CN102715850A (en) * 2012-07-10 2012-10-10 江苏顺发电器有限公司 Full-automatic grinding machine

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR200331665Y1 (en) * 2003-08-06 2003-10-30 김홍배 Heating controller of a soybean milk maker

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102273934A (en) * 2011-05-27 2011-12-14 浙江绍兴苏泊尔生活电器有限公司 Multifunctional operation mode grinding soybean milk machine and speed-regulating grinding method thereof
CN102327062A (en) * 2011-07-30 2012-01-25 浙江绍兴苏泊尔生活电器有限公司 Grinding soybean milk machine and anti-stalling method thereof
CN102715850A (en) * 2012-07-10 2012-10-10 江苏顺发电器有限公司 Full-automatic grinding machine

Also Published As

Publication number Publication date
CN105982583A (en) 2016-10-05

Similar Documents

Publication Publication Date Title
CN105982583B (en) Food processor and anti-stalling method thereof
CN102327062B (en) Grinding soybean milk machine and anti-stalling method thereof
CN109152491B (en) Heating and stirring cooker
RU2635794C2 (en) Upgraded desk-type mixer
CN103908161B (en) Soy bean milk making machine pulping process
RU2689044C2 (en) Detection of tool for kitchen appliances
US20180140138A1 (en) Agitation mill type automatic cooking apparatus
CN104825055B (en) A kind of soy bean milk making machine
CN107374407B (en) Control method of soybean milk machine
CN106510495A (en) Multifunctional food processing platform
CN105435917B (en) A kind of food refuse disposer and its control method
CN103860061B (en) A kind of Multifunctional built-in cooking machine
JP2004321840A (en) Disposer
CN105768958A (en) Food processor and temperature control method thereof
CN106102523B (en) Control method, cooking equipment and the soy bean milk making machine of the heating unit of cooking equipment
CN103815804A (en) Embedded multifunctional food processor
CN107296475B (en) Vacuum pumping method and food cooking machine
CN107071951A (en) The stirring antenna module of microwave cooking utensil and microwave cooking utensil
CN205433439U (en) Intelligence food processing platform
CN206303802U (en) A kind of food processor
CN106440255A (en) Fan control method, fan control system, fan and air conditioner
CN110618727A (en) Food processor and control method and control device thereof
CN213248331U (en) Food material processing appliance and pot detection device thereof
KR20100119656A (en) Waste load sensing method by speed commend voltage and waste treatment apparatus using the same
KR101705132B1 (en) Food Waste Treating Method Using Temperature and Load Sensing And Food Waste Treatment System using the same

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant