CN203340289U - Voice communication terminal and voice communication system - Google Patents

Voice communication terminal and voice communication system Download PDF

Info

Publication number
CN203340289U
CN203340289U CN201320283159XU CN201320283159U CN203340289U CN 203340289 U CN203340289 U CN 203340289U CN 201320283159X U CN201320283159X U CN 201320283159XU CN 201320283159 U CN201320283159 U CN 201320283159U CN 203340289 U CN203340289 U CN 203340289U
Authority
CN
China
Prior art keywords
voice communication
voice
communication terminal
terminal
main control
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
CN201320283159XU
Other languages
Chinese (zh)
Inventor
尚涛鸣
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.)
SHENZHEN EDUCATIVE TECHNOLOGY Ltd
Original Assignee
SHENZHEN EDUCATIVE TECHNOLOGY 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 SHENZHEN EDUCATIVE TECHNOLOGY Ltd filed Critical SHENZHEN EDUCATIVE TECHNOLOGY Ltd
Priority to CN201320283159XU priority Critical patent/CN203340289U/en
Application granted granted Critical
Publication of CN203340289U publication Critical patent/CN203340289U/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Landscapes

  • Telephonic Communication Services (AREA)

Abstract

The utility model relates to a voice communication terminal and a voice communication system. The voice communication system comprises the voice communication terminal, a server, and at least one terminal device, wherein the voice communication terminal establishes voice communication with at least one terminal device through the network server; the voice communication terminal comprises a main control module, a wireless network module, a sound recording trigger press key, a listening trigger press key and at least one object choosing press key; the wireless network module is connected with the input and output ends of the main control module; the sound recording trigger press key, the listening trigger press key and at least one object choosing press key are respectively connected with the input end of the main control module; each object choosing press key corresponds to a communication object, and each object choosing press key is used for triggering the main control module to establish voice communication with the terminal device used by the communication object corresponding to the object choosing press key through the wireless network module and the network server Through application of the voice communication terminal and the voice communication system, normal wireless network voice communication can be realized by a user through simple physical press key operation in a simple and convenient manner.

Description

Voice communication terminal and voice communication system
Technical field
The utility model relates to the voice communication technology, more particularly, relates to a kind of voice communication terminal and voice communication system.
Background technology
Along with the development of intelligent terminal and development of Mobile Internet technology, speech talkback application software (as micro-letter, footpath between fields, footpath between fields, hundred are chatted, prosperous letter etc.) is universal rapidly, by wireless network (as 3G, WIFI etc.), realizes voice communication.But it can only be realized based on intelligent terminals such as mobile phone, panel computers as a kind of application software.Yet most users of intelligent terminal are normal adults.For specific groups such as numerous children, the elderly, blind persons, due to the impact that is subject to its know-how or eyesight level or other restrictions, fail to understand or do not see the Word message on the intelligent mobile terminal screen, can not carry out correct operation to the speech talkback application software function on intelligent mobile terminal, can't well realize the speech talkback application.Therefore, existing voice communication technology has larger use limitation for specific groups such as children, the elderly, blind persons.
The utility model content
The technical problems to be solved in the utility model is, for specific groups such as children, the elderly, blind persons, the circumscribed defect of larger use is arranged for the existing voice communication technology, a kind of voice communication terminal and voice communication system are provided, allow the user just can realize normal wireless network voice communication by simple physical button operation, simple and convenient.
The utility model provides a kind of voice communication terminal, and described voice communication terminal is realized the voice communication with at least one terminal equipment by the webserver; Described voice communication terminal comprise main control module, the wireless network module be connected with the input/output terminal of described main control module and with the input of described main control module, be connected respectively trigger button, for playing the listening to of voice signal that described voice communication terminal receives, trigger button and at least one Object Selection button for triggering recording that voice signal that described voice communication terminal will send the user gathered; The corresponding communication object of each Object Selection button, and set up voice communication for triggering the terminal equipment that described main control module comes the communication object corresponding with described Object Selection button to use by described wireless network module and the described webserver.
Preferably, described voice communication terminal also comprise with the output of described main control module, be connected and with each Object Selection button at least one communication prompt module one to one.
Preferably, described voice communication terminal also comprises the memory be connected with the input/output terminal of described main control module.
Preferably, described voice communication terminal also comprises the voice acquisition module be connected with the input/output terminal of described main control module and the voice playing module be connected with the output of described main control module.
Preferably, described wireless network module is wireless lan adapter and/or 3G wireless Internet card.
Preferably, described communication prompt module is the LED signal lamp.
Preferably, described memory is the SD card.
Preferably, described voice acquisition module is microphone; Described voice playing module is loud speaker.
The utility model also provides a kind of voice communication system, and described voice communication system comprises above-mentioned voice communication terminal, the webserver and at least one terminal equipment; Described voice communication terminal sends voice signal and receives the voice signal from described at least one terminal equipment by the described webserver to described at least one terminal equipment by the described webserver.
Preferably, described terminal equipment is terminal equipment or the intelligent terminal with hardware configuration identical with described voice communication terminal.
Implement voice communication terminal of the present utility model and voice communication system, there is following beneficial effect: the user just can be realized by the operation of simple physical button and a plurality of terminal equipment between the wireless network voice communication, simple and convenient, be applicable to very much the specific groups such as children, the elderly, blind person.
The accompanying drawing explanation
Below in conjunction with drawings and Examples, the utility model is described in further detail, in accompanying drawing:
Fig. 1 is the structural representation of voice communication system the first embodiment of the present utility model;
Fig. 2 is the structural representation of voice communication system the second embodiment of the present utility model.
Embodiment
As shown in Figure 1, the voice communication system of the utility model the first embodiment comprises voice communication terminal 100, the webserver 200 and at least one terminal equipment 300.Voice communication terminal 100 is set up voice communication by the webserver 200 and at least one terminal equipment 300.As voice communication terminal 100 sends voice signal and the voice signal from least one terminal equipment 300 by the webserver 200 receptions by the webserver 200 at least one terminal equipment 300.Wherein, voice communication terminal 100 comprises main control module 101, the wireless network module 102 be connected with the input/output terminal of main control module 101 and the recording that is connected with the input of main control module 101 respectively triggers button 103, listens to and trigger button 104 and at least one Object Selection button 105.The corresponding communication object of each Object Selection button 105, be that each Object Selection button 105 is set up associated with a communication object in advance, the communication object here refers to User Identity information, for example be similar to micro-signal, No. QQ such user account number, it can reach the standard grade to communicate by login on a terminal equipment 300.Object Selection button 105 is set up voice communication for the terminal equipment 300 that triggers main control module 101 and use by wireless network module 102 and the webserver 200 communication object corresponding with Object Selection button 105.
Main control module 101 can comprise process chip and random asccess memory, and random asccess memory is the instruction and data for this voice communication terminal for storage, and process chip can adopt the processors such as ARM, DSP, CPU, MPU, MCU, for the treatment of various operational orders.Main control module 101 is for triggering under the priority triggering of button 103 at Object Selection button 105 and recording, the voice signal that 100 couples of users of control voice communication terminal will send is gathered, then gathered voice signal is processed, and by wireless network module 102, the voice signal after this processing is sent to the webserver 200, carry the user by the information of Object Selection button 105 selected communication objects simultaneously, so that the webserver 200 is forwarded to user's terminal equipment corresponding by the selected communication object of Object Selection button 105 (that terminal equipment that this communication object login is used) by this voice signal, main control module 101 is the voice signal for receiving from terminal equipment from the webserver 200 by wireless network module 102 also, under Object Selection button 105 and the priority of listening to triggering button 104 trigger, the voice signal that carrys out self-corresponding communication object is processed, and controlled the voice signal after voice communication terminal 100 is play this processing.
Wireless network module 102 can adopt wireless lan adapter, as utilized the WIFI network of family.Wireless network module 102 also can adopt the 3G wireless Internet card, as do not had under the WLAN (wireless local area network) condition, and the ability of the content in the data network provided by the mobile operator request of obtaining and access web server 200.
Recording triggers button 103 and can be installed on the housing of voice communication terminal 100, for triggering the voice signal that 100 couples of users of voice communication terminal will send, is gathered.Especially, can control in the long mode by recording triggering button 103 collection of voice signal, when the user presses recording triggering button 103, recording triggers button 103 and just to main control module 101, sends a record command, the voice signal that main control module 101 will send according to 100 couples of users of this record command control voice communication terminal is gathered, when the user stops pressing recording triggering button 103, recording triggers button 103 and just sends a halt instruction to main control module 101, main control module 101 controls according to this halt instruction the collection that voice communication terminal 100 stops user's voice signal.
Listen to triggering button 104 and can be installed on the housing of voice communication terminal 100, the voice signal received for playing described voice communication terminal (100).When the user successively presses Object Selection button 105 and listen to triggering button 104, Object Selection button 105 and listen to and trigger button 104 and just send a subject instructions and listen to instruction to main control module 101 respectively, main control module 101 is controlled voice communication terminal 100 and is play institute's received speech signal from the communication object of Object Selection button 105 correspondences after receiving this subject instructions and listening to instruction.
Object Selection button 105 can be installed on the housing of voice communication terminal 100.The Object Selection button 105 of any amount can be set according to actual needs.For example, three Object Selection buttons are set on the housing of voice communication terminal 100, each Object Selection button is corresponding to a communication object, each Object Selection button is set up associated with a communication object in advance, for example, the first Object Selection button is associated with communication object " father " foundation, and the second object selection key is associated with communication object " mother " foundation, and the 3rd Object Selection button is set up associated with communication object " elder brother ".Especially, the user can preset or revise these incidence relations by voice communication terminal 100 of the present utility model is connected to computer.Voice communication terminal 100 can be given tacit consent to particular user identity of binding sign, also can change at any time other User Identity of binding, can correspondingly change the incidence relation of each Object Selection button 105 according to the change of this User Identity.When the user presses one of them Object Selection button 105, Object Selection button 105 just sends an Object Selection instruction to main control module 101, informs that main control module 101 users now need which communication object to carry out voice communication to make corresponding voice data transmission with.
As shown in Figure 2, the voice communication terminal 100 in the voice communication system of the utility model the second embodiment also comprises at least one communication prompt module 106, memory 107, voice acquisition module 108 and voice playing module 109.Wherein, communication prompt module 106 is connected with the output of main control module 101; Memory 107 is connected with the input/output terminal of main control module 101; Voice acquisition module 108 is connected with the input/output terminal of main control module 101; Voice playing module 109 is connected with the output of main control module 101.
Communication prompt module 106 and the corresponding setting one by one of an Object Selection button 105, communication prompt module 106 can be the LED signal lamp be installed on the housing of voice communication terminal 100.Each LED signal lamp is respectively used to the signal intelligence of the prompting Object Selection button corresponding communication object corresponding with it, for example, the LED signal lamp be take the mode of Chang Liang and is meaned that corresponding communication object is as presence, means to receive the voice messaging of corresponding communication object in the mode of flicker.For example, when communication object " father " is online, the LED signal lamp Chang Liang corresponding with communication object " father ", when receiving the voice messaging that communication object " father " sends over, the LED flashing corresponding with communication object " father ".
Voice acquisition module 108 can be microphone, the voice signal that will send for gathering the user.Particularly, in recording, trigger under the triggering of button 103, the voice signal that 108 couples of users of main control module 101 control voice acquisition module will send is gathered.
Voice playing module 109 can be loud speaker, for playing the voice signal received.Particularly, under Object Selection button 105 and the priority of listening to triggering button 104 trigger, main control module 101 is controlled voice playing modules 109 and play the voice signal received from the communication object of Object Selection button 105 correspondences.
Memory 107 can be SD card etc., for interim storage, needs the voice signal that sends and received, as the speech data gathered by voice acquisition module 108 and the speech data obtained from the webserver 200 by wireless network module 102.
Other situations of voice communication system the second embodiment of the present utility model are identical with the first embodiment, do not repeat them here.
In above-mentioned two embodiment, terminal equipment 300 can have the hardware configuration identical with voice communication terminal 100 of the present utility model, can be also intelligent terminal, and this intelligent terminal stores the instruction and data relevant to voice communication terminal 100 communications.Each communication object, by using terminal equipment 300 logins to reach the standard grade, signs in to the webserver 200.
In addition, voice communication terminal 100 of the present utility model also has sound prompt function, and main control module 101 can be controlled voice playing module 109 and play corresponding pre-stored voice suggestion sound.For example, when voice communication terminal 100 receives a new voice messaging, play voice suggestion sound " you have one section fresh information, please listen in time "; When the user presses the Object Selection button and will be recorded, play voice suggestion sound " speech talkback starts, and please pin the record button speech " etc.
For the utility model is described better, below will be described of the present utility model one better implementation process.
Suppose that the first Object Selection button on voice communication terminal 100 set up associated with communication object " father " in advance, it is associated that second object selection key and communication object " mother " have been set up in advance, and the 3rd Object Selection button has been set up associated with communication object " elder brother " in advance.And communication object " father " can login with terminal equipment 300-A and reach the standard grade, communication object " mother " can be logined with terminal equipment 300-B and reach the standard grade, and communication object " elder brother " can be logined and reach the standard grade with terminal equipment 300-C.
When voice communication terminal 100 starts are reached the standard grade, the webserver 200 detects voice communication terminal 100 and reaches the standard grade, thereby detect its three communication objects " father " that are associated, whether " mother " and " elder brother " be online, and testing result is informed to voice communication terminal 100.For example, communication object " father " is online, communication object " mother " and communication object " elder brother " are not online, the LED signal lamp that the first Object Selection button of voice communication terminal 100 is corresponding is luminous, for normal bright state, online to mean communication object " father " network, until communication object " father " rolls off the production line and extinguishes; The LED signal lamp that the LED signal lamp that the second object selection key of voice communication terminal 100 is corresponding and the 3rd Object Selection button are corresponding is all not luminous, not online to mean respectively communication object " mother " and " elder brother " network.When carrying out voice communication, at first the user determines by pressing Object Selection button 105 object of wanting conversation, for example presses the first Object Selection button and comes to carry out voice communication with communication object " father ".When the user presses the first Object Selection button, but playing alert tones " speech talkback starts, and please pin the record button speech ".The user is then long says one section word by record button facing to microphone, talk and completely unclamp recording and trigger button 103, main control module 101 gathers the voice analog signal of one section speech of user by voice acquisition module 108, and gathered voice analog signal is converted into to the first voice digital signal, again the first voice digital signal is sent to the webserver 200 by wireless network module 102, informs the corresponding phonetic incepting object of the webserver 200 (being communication object " father ") simultaneously.It is online that the webserver 200 detects communication object " father ", according to user name and the network ip address of communication object " father ", the first voice digital signal is sent to terminal equipment 300-A, terminal equipment 300-A receives the first voice digital signal and is translated into voice analog signal and play by its loud speaker.Especially, if it is not online communication object " father " to be detected, the first voice digital signal is temporary in the memory of the webserver 200, by the time communication object " father " next time while reaching the standard grade, then the first voice digital signal is sent to communication object " father " logins terminal equipment 300-A used.
In like manner, communication object " father " also can send one section voice digital signal to voice communication terminal 100 by terminal equipment 300-A.At first, terminal equipment 300-A is sent to the webserver 200 by one section second voice digital signal, inform the corresponding phonetic incepting object of the webserver 200 (as the user of voice communication terminal 100 correspondences) simultaneously, it is online that the webserver 200 detects voice communication terminal 100 starts, and the second voice digital signal is sent to voice communication terminal 100, inform the transmit leg (being communication object " father ") of voice communication terminal 100 these the second digital signals simultaneously, voice communication terminal 100 receives the second voice digital signal, and it is stored in memory 107, now, the LED lamp flashing that the first Object Selection button is corresponding, with the new speech message of reminding voice communication terminal 100 users to have communication object " father " to send, but simultaneously also playing alert tones " you have one section fresh information, please listen in time " to remind voice communication terminal 100 users.Voice communication terminal 100 users first press the first Object Selection button, then press and listen to button, and main control module 101 just is converted into voice analog signal by the second voice digital signal in memory 107 and is play by its loud speaker.Especially, if voice communication terminal 100 being detected does not start shooting not online, the second voice digital signal is temporary in the memory of the webserver 200, when voice communication terminal 100 starts are by the time reached the standard grade, then the second voice digital signal is sent to voice communication terminal 100.
In like manner, the terminal equipment 300-B that communication object " mother " is used or communication object " elder brother " the terminal equipment 300-A that uses of voice communication situation between the terminal equipment 300-C that uses and voice communication terminal 100 and communication object " father " identical with the voice communication situation between voice communication terminal 100, do not repeat them here.
The utility model is by the speech talkback application software being carried out to software data structure optimization and making corresponding hardware modifications, and the feature operation of speech talkback application software and electronic hardware are made to combination.Allow the user not need to by see the mobile phone or panel computer on display screen carry out corresponding voice operating, and just by pressing the physical button on voice communication terminal of the present utility model, can realize the voice communication with one or more users, simple and convenient, be applicable to very much the specific groups such as children, the elderly, blind person.
Voice communication terminal of the present utility model can be designed to a kind of toy for children, the elderly or blind person's dedicated voice intercom etc. with speech talkback function, is widely used.
The foregoing is only preferred embodiment of the present utility model; not in order to limit the utility model; all any modifications of doing within spirit of the present utility model and principle, be equal to and replace and improvement etc., within all should being included in protection range of the present utility model.

Claims (10)

1. a voice communication terminal, is characterized in that, described voice communication terminal (100) is set up voice communication by the webserver (200) and at least one terminal equipment (300), described voice communication terminal (100) comprises main control module (101), the wireless network module (102) be connected with the input/output terminal of described main control module (101) and with the input of described main control module (101), be connected respectively trigger button (103) for triggering the recording that voice signal that described voice communication terminal (100) will send the user gathered, trigger button (104) and at least one Object Selection button (105) for playing the listening to of voice signal that described voice communication terminal (100) receives, the corresponding communication object of each Object Selection button (105), and set up voice communication for triggering the terminal equipment (300) that described main control module (101) uses by described wireless network module (102) and the described webserver (200) communication object corresponding with described Object Selection button (105).
2. voice communication terminal according to claim 1, it is characterized in that, described voice communication terminal (100) also comprise with the output of described main control module (101), be connected and with each Object Selection button (105) at least one communication prompt module (106) one to one.
3. voice communication terminal according to claim 2, is characterized in that, described voice communication terminal (100) also comprises the memory (107) be connected with the input/output terminal of described main control module (101).
4. voice communication terminal according to claim 3, it is characterized in that, described voice communication terminal (100) also comprises the voice acquisition module (108) be connected with the input/output terminal of described main control module (101) and the voice playing module (109) be connected with the output of described main control module (101).
5. voice communication terminal according to claim 1, is characterized in that, described wireless network module (102) is wireless lan adapter and/or 3G wireless Internet card.
6. voice communication terminal according to claim 2, is characterized in that, described communication prompt module (106) is the LED signal lamp.
7. voice communication terminal according to claim 3, is characterized in that, described memory (107) is the SD card.
8. voice communication terminal according to claim 4, is characterized in that, described voice acquisition module (108) is microphone; Described voice playing module (109) is loud speaker.
9. a voice communication system, is characterized in that, described voice communication system comprises as the described voice communication terminal of claim 1-8 any one (100), the webserver (200) and at least one terminal equipment (300); Described voice communication terminal (100) sends voice signal and receives the voice signal from described at least one terminal equipment (300) by the described webserver (200) to described at least one terminal equipment (300) by the described webserver (200).
10. voice communication system according to claim 9, is characterized in that, described terminal equipment (300) is terminal equipment or the intelligent terminal with hardware configuration identical with described voice communication terminal (100).
CN201320283159XU 2013-05-22 2013-05-22 Voice communication terminal and voice communication system Expired - Lifetime CN203340289U (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201320283159XU CN203340289U (en) 2013-05-22 2013-05-22 Voice communication terminal and voice communication system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201320283159XU CN203340289U (en) 2013-05-22 2013-05-22 Voice communication terminal and voice communication system

Publications (1)

Publication Number Publication Date
CN203340289U true CN203340289U (en) 2013-12-11

Family

ID=49708939

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201320283159XU Expired - Lifetime CN203340289U (en) 2013-05-22 2013-05-22 Voice communication terminal and voice communication system

Country Status (1)

Country Link
CN (1) CN203340289U (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015149456A1 (en) * 2014-04-02 2015-10-08 小米科技有限责任公司 Voice communication method and voice playing method and apparatus
CN105007543A (en) * 2014-04-18 2015-10-28 腾讯科技(深圳)有限公司 Intercommunication method, apparatus, device and system
CN105812918A (en) * 2014-12-30 2016-07-27 Tcl海外电子(惠州)有限公司 Television voice information acquisition method and television voice information acquisition system
CN105867143A (en) * 2016-03-31 2016-08-17 美的集团股份有限公司 Speech box and speech box pairing method
CN106253934A (en) * 2016-08-26 2016-12-21 南京纳加软件股份有限公司 IPization live intercommunication communication system
CN110213424A (en) * 2018-09-06 2019-09-06 上海伴我科技有限公司 End user communication device

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2015149456A1 (en) * 2014-04-02 2015-10-08 小米科技有限责任公司 Voice communication method and voice playing method and apparatus
US10057424B2 (en) 2014-04-02 2018-08-21 Xiaomi Inc. Method for voice calling, method for voice playing and devices thereof
CN105007543A (en) * 2014-04-18 2015-10-28 腾讯科技(深圳)有限公司 Intercommunication method, apparatus, device and system
CN105812918A (en) * 2014-12-30 2016-07-27 Tcl海外电子(惠州)有限公司 Television voice information acquisition method and television voice information acquisition system
CN105867143A (en) * 2016-03-31 2016-08-17 美的集团股份有限公司 Speech box and speech box pairing method
CN106253934A (en) * 2016-08-26 2016-12-21 南京纳加软件股份有限公司 IPization live intercommunication communication system
CN110213424A (en) * 2018-09-06 2019-09-06 上海伴我科技有限公司 End user communication device
CN110213424B (en) * 2018-09-06 2023-10-13 上海伴我科技有限公司 terminal communication device

Similar Documents

Publication Publication Date Title
CN203340289U (en) Voice communication terminal and voice communication system
CN106447836B (en) A kind of door control terminal binding method and relevant device
CN203289452U (en) Wireless audio system based on acoustic wave communication pairing
CN101599224A (en) A kind of demo system and portable terminal and wireless Internet card
CN110650405A (en) Wireless earphone control system, method, device and storage medium
CN103369158B (en) Party call control and relevant device and communication system
CN111124569B (en) Application sharing method, electronic device and computer readable storage medium
CN103607779A (en) Multi-screen coordination intelligent input system and realization method thereof
CN108595003A (en) Function control method and relevant device
CN108600887B (en) Touch control method based on wireless earphone and related product
CN108124114A (en) A kind of audio/video conference sound collection method and device
CN109960581B (en) Hardware resource allocation method and device, mobile terminal and storage medium
CN115810356A (en) Voice control method, device, storage medium and electronic equipment
CN105553829A (en) Instant messaging method and apparatus
WO2015078349A1 (en) Microphone sound-reception status switching method and apparatus
CN109257152A (en) A kind of resource indicating method, network side equipment and terminal
CN108696842A (en) A kind of equipment and its network-building method, output method
CN109993951B (en) Doorplate system and control method and device thereof
CN105049090A (en) Solar cell type electronic communication apparatus
CN202503580U (en) Multifunctional communication device
CN107635272A (en) Control method of electronic device and device
CN203206404U (en) Smart type television integration application device
CN103124372A (en) Multifunctional remote controller
CN103701973B (en) A kind of convenient calling terminal of intelligence
CN107645604B (en) Call processing method and mobile terminal

Legal Events

Date Code Title Description
C14 Grant of patent or utility model
GR01 Patent grant
CX01 Expiry of patent term

Granted publication date: 20131211

CX01 Expiry of patent term