CN201035392Y - Bus type numerical control system - Google Patents
Bus type numerical control system Download PDFInfo
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- CN201035392Y CN201035392Y CNU2007200101281U CN200720010128U CN201035392Y CN 201035392 Y CN201035392 Y CN 201035392Y CN U2007200101281 U CNU2007200101281 U CN U2007200101281U CN 200720010128 U CN200720010128 U CN 200720010128U CN 201035392 Y CN201035392 Y CN 201035392Y
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Abstract
The utility model relates to a numerical control system, wherein, the main device comprises an upper machine (1) and a bus controller (2); the main device also comprises a serving driver(3) connected in serial with the main device through transmission line and PLC slave devices connected in parallel with the main device, so as to form a closed loop; the data is transmitted between the main device and the slave devices through a link circuit formed by connecting a physical layer and transmission medium; in normal condition, the information sent by the upper machine can only be transmitted to each slave device unidirectionally and successively and each slave device feeds back the information to the upper machine through the lower slave device; all kinds of information are transmitted in a data telegram way in the transmission line, including the order information of the main device, the data fed back from the slave device and the data to trigger the execute command of the slave device. As the numerical control system of the utility model has superior controlling capability, the high precision of the numerical control machine tool can be ensured under the high-speed feed motion.
Description
Technical field
The utility model relates to Electrical equipment of industrial machines control field, more particularly, relates to a kind of digital control system that realizes many Electric Machine Control.
Background technology
Digital servo device is important milestone on the numerical control development history.Adopt digital servo device, all command value and actual value can both be finished in a microcontroller.Not only can realize the control of traditional torsion loop and speed ring, and can finish smart interpolation in the short time, realize position ring control at the utmost point.Compare with traditional analog-servo mechanism, adopt digital servo device can obtain higher process velocity and machining precision, and control hardware is simple, the complicacy of system and cost all reduce greatly
Be accompanied by the development of digital servo device, how realize that the data communication between control module and the digital servo device becomes a key issue.Be necessary for control module and digital servo device and cooperate suitable digital interface, design suitable system architecture, could guarantee to follow the relevant device that certain standard development goes out and have good interchangeability.
Summary of the invention
The utility model is at the problems referred to above, a kind of architecture of digital control system has been proposed, rely on and be the custom-designed communication protocol of numerical control device, setting and problems such as fault diagnosis and processing at the configuration of the composition of the topological structure of system, data line, signal encoding form, telegram structure, work schedule, interface initialization, cycle data and transmission, servo operation pattern aim to provide the perfect numerical control system of a cover.
In order to solve the problems referred to above that occur in setting up systematic procedure, the utility model has been constructed a kind of bus-type numerical control system, comprises host computer, full digital servo-driver, motor and programmable controller PLC that numerical control software is housed.Host computer and bus controller constitute main equipment; Slave unit comprises servo-driver and PLC.Servo-driver sends drive signal to motor, and motor is sent the signal of position detecting device feedback back to servo-driver by circuit simultaneously.The characteristics of the utility model digital control system are, thereby main equipment is connected in series a plurality of slave units successively and finally connecting back main equipment constitutes a closed circuit, and the link transmission data by being connected with transmission medium with Physical layer between main equipment and the slave unit.In the transmission of Information process, main equipment only sends main information to direct-connected first order slave unit with it, and this main information comprises the information relevant with all slave units, as command information, data message and trigger the exectorial information of certain one-level slave unit.And main information will according to the order of serial connection slave unit only successively one-way transmission to each slave unit.Correspondingly, certain one-level slave unit receives, responds information associated in the main information and provides feedback information; The feedback information of each slave unit is transmitted back main equipment according to the order of serial connection slave unit is unidirectional successively by each slave unit of subordinate.
Above-mentioned data communication is only carried out between main equipment and slave unit, in the transmission course slave unit receive only main equipment to self order and service data and handle, data to other slave units are only transmitted, and do not handle, and do not carry out independent exchanges data between the slave unit.
The utility model has been constructed a kind of bus-type numerical control system, and its characteristics are that also the transmission medium of Physical layer is selected ethernet physical layer or 1394 Physical layers or USB Physical layer for use.Under the optimal way, the transmission medium of Physical layer is selected ethernet physical layer for use.
The utility model has been constructed a kind of bus-type numerical control system, and it further improves and is, is occurring under the broken string situation, and slave unit transmits by the transmission line reverse data, thereby constitutes closed loop so that further fault handling with main equipment.
The utility model has been constructed a kind of bus-type numerical control system, and its further improvement is that also bus controller is provided with the interface that directly connects machine tool keyboard by transmission line; PLC function that the servo driving of serial connection is integrated; And the feedback information of above-mentioned slave unit comprises supply voltage abnormal information, scrambler broken string information, communication data error message, servomechanism installation warning message, PLC warning message etc.
The invention also discloses the method that realizes numerical control device control based on above-mentioned bus-type numerical control system, as mentioned above, in system, the main equipment that comprised host computer, bus controller is connected in series the formation loop successively with the slave unit that has comprised servo-driver, PLC.Control procedure is: 1, main equipment sends the datagram that comprises command information, data message; 2, slave unit inquiry and reception comprise the telegram of described command information, data message; 3, main equipment sends the datagram that comprises fill order information; 4, slave unit inquiry and reception comprise the datagram of fill order information, and a certain slave unit needs under the exectorial state definite, and locking transmission data are also carried out corresponding operating.So-called locking data is meant current no longer to subordinate's slave unit forwarding information.
Above-mentioned the utility model bus-type numerical control system is to the control method of numerical control device, it further improves and is, in step 4, slave unit sends back main equipment by the slave unit of subordinate successively with feedback information, feedback information comprises supply voltage abnormal information, scrambler broken string information, communication data error message, servomechanism installation warning message, PLC warning message, thereby main equipment sends command information once more according to described feedback information.And occurring under the broken string situation, slave unit oppositely transmits back failure message main equipment by higher level's slave unit successively, thereby constitutes closed loop so that carry out fault handling with main equipment.In addition, bus controller directly connects machine tool keyboard by transmission line, thereby main equipment is with the control input of highest priority state response machine tool keyboard.
In control procedure, under the initial open state, main equipment visit first order slave unit and be that its allocation base address and work are with record, according to this record access second level slave unit allocation base address record once more in order; After this successively according to the higher level be recorded as subordinate's slave unit allocation base address in order, finish initial configuration.
By technique scheme, according to the topological structure of the utility model digital control system, can obtain high-grade bus-type numerical control system system, can reach following beneficial effect:
1, open bus structure, HRP-configured slave device flexibly of annular
Slave unit quantity in the bus structure can be configured when Design of CNC System as required.For example the Control Shaft quantity of lathe has 3, PLC counts when requiring 72 inputs/48 outputs, 6 of slave unit quantity configuration journeys (suppose that bus protocol is set at a slave unit with 24 inputs/16 outputs with PLC, 72 inputs/48 output equivalents are the slave unit of 3 PLC types).During Machine Tool design, when the number of coordinates of controlled axle or control changes, can be as required with the corresponding renewal of the configuration carrying out of the slave unit on the bus.
2, at a high speed:
Can adopt the high-speed physical layer as required, maximum transmission rate can reach 800Mbps
3, control accuracy height
The data of this system's numerical control software send to driver by bus with digital form, are not subjected to the restriction of DA and AD converter part, according to control accuracy and needs setting data transmission number of significant digit, can effectively improve transmission precision.Simultaneously owing to be different from the control of traditional analog amount, can avoid simulated data that analog quantity when control occur numeral-＞simulation-＞drift of sum of errors amplifying element in the digital conversion process, and the sign mutation equal error that causes of other interference, reduced the system debug complexity.Design attitude and several times transmission precision reach 16bit, position detecting device feedback data figure place reaches 24bit.
4, good reliability
Do not have the analog quantity transmission link, the analog quantity error that digital signal can fundamentally avoid being subjected in the transmission course influence of undesired signal to cause is disturbed.Error Control and verification control algolithm are set in the bus protocol, can suppress error code and interference in the transmission course effectively.
5, the system assembles debugging is simple, and cost is low
Traditional relatively numerical control architecture, simulation control part in the middle of saving, the Installation and Debugging difficulty obviously reduces, and cost also effectively reduces thereupon
6, servo-drive system integrated level height
Integrated PLC input-output device in the servo-drive system saves external PLC input and output configuration, and integrated level improves, and cost reduces.
7, controlled slave unit quantity reaches 24, can 5 interlocks realize complicated digital control system demand.
8, executive capability is: 2000 sections/second of NC instructions, and PLC instructs 40 microseconds/thousand;
9, Zhuo Yue High-speed Control ability: during resolution 1 μ m, speed of feed can reach 240m/min;
10, maximum 6 main shafts of may command can be supported 3 handwheels at most;
11, high speed PLC meets the IEC61131-3 standard.
12, customizable user's specific function, customizable user's man-machine interface;
13, can expand the memory capacity of NC code, reach more than the 40GB
14, many CAM and CAD software be can move, simulation processing in early stage and 3D emulation carried out.
Description of drawings
Fig. 1 is the composition of data line in the utility model digital control system;
Fig. 2 is the synoptic diagram of the topological structure of a kind of embodiment of the utility model digital control system;
Fig. 3 is the synoptic diagram of the topological structure of second kind of embodiment of the utility model digital control system;
Fig. 4 is the synoptic diagram of the topological structure of the third embodiment of the utility model digital control system;
Fig. 5 is the circulation sequential synoptic diagram of realizing in a kind of embodiment of the utility model digital control system;
Fig. 6 be with the same embodiment of Fig. 5 in the data structure diagram realized;
Fig. 7 be with the same embodiment of Fig. 6 in the write section divided data organization chart realized;
Fig. 8 be with the same embodiment of Fig. 6 in realize read the partial data organization chart.
Embodiment
In order to realize digital control system of the present utility model, can define a kind of host-host protocol aspect two of Physical layer and data link layers, main contents comprise: the setting of the configuration of the composition of topological structure, data line, signal encoding form, telegram structure, work schedule, aperiodicity data transmission, interface initialization, cycle data and transmission, servomechanism installation operational mode and fault diagnosis and processing etc.This paper only provides a kind of feasible program with regard to foregoing, and desire realizes the utility model, and in conjunction with concrete condition, the definition of agreement can change, and does not protect all improvement of main points all to include in protection domain of the present utility model but break away from the utility model.
1, Physical layer
Physical layer is positioned at the lowermost layer of communication system, it is the basis of whole communication, for the data communication between the equipment provides transmission medium (cable, optical fiber etc.) and InterWorking Equipment (plug, socket etc.),, be responsible for data transmission and relevant management work for data transmission provides path.The physical layer protocol of system has mainly defined the composition of topological structure, data line and signal encoding form etc.
2, topological structure
System uses loop structure as the most basic topology, and loop is made up of master and slave equipment and transmission line, and each loop has only a main equipment, and all the other all are slave unit.The link transmission data that connects by ethernet physical layer between each equipment, data are uniflux on transmission line.
As shown in Figure 2, the type of attachment of main equipment (comprising bus controller) and slave unit (comprising digital bus type servo controller).A main equipment can be with a plurality of slave units, and the maximum slave unit that can connect as loop of design at present is 24, leaves and can expand leeway.
Attention: though interconnected between each slave unit by category 5 twisted pair, can not directly carry out data communication between each slave unit, slave unit can only receive the order of main equipment and data and make corresponding reaction and return data according to the corresponding command.Arrange successively from low to high according to the order of connection on the link address of each slave unit.
3, the composition of data line
With the ethernet physical layer is example, specific to the wall scroll data line, is made up of 3 parts altogether.The ethernet physical layer chip of forward transmitting terminal, receive the normal data that upper control chip sends over, become serial data to transmit this data conversion, as shown in Figure 1, forward data and reverse data send simultaneously, under the situation that slave unit does not break down, only use forward data to carry out data and transmit, when running into the fault that broken string or other slave units can not communicate by letter, reverse data plays the passback data, form ring closure, use for handling failure.
4, signal encoding form
Relevant with the physical layer transmission medium and the agreement that are adopted, support ethernet physical layer at present, 1394 Physical layers, USB Physical layer.The employing ethernet physical layer is an example: finish the conversion of 4B-5B code system in Physical layer, realize the Differential Manchester Encoding transmission on the category 5 twisted pair.
5, telegram basic structure
In system interface, all data all are to transmit with the form of datagram.Concrete condition is as described below.
5.1 the circulation sequential organization of host-host protocol
The circulation of an agreement is sent by 2 spaced data and forms as seen from Figure 5: the quick byte frame of the Frame of 962 bytes, 8 bytes.Wherein, the Frame function of 962 bytes comprises that main equipment issues the order of slave unit and the data that slave unit returns.The function of the quick byte frame of 8 bytes comprises that order and data synchronization that main equipment sends enable, i.e. the information of directive command execution.
Concrete frame structure is described below:
962 (962=2+40 * 24) byte data frames is with 16 system AA, and BB follows the order and the Frame of 24 slave units afterwards as start byte, 40 byte spaces of each devices allocation.
5.2 slave unit data structure
The slave unit data are divided into and join 40 byte spaces as shown in Figure 6, and wherein preceding 16 bytes are come the data that write of autonomous device, and back 24 bytes are the data that turn back to main equipment.Write data division data organizational structure as shown in Figure 7, read the partial data institutional framework as shown in Figure 8.
6, the initial configuration of interface initialization and slave unit
The base address of all slave units all will be changed to F8H after powering on.For fear of address conflict, all slave units connect with ring form, that is to say that disposing preceding host computer can only visit first slave unit.
The first step of configuration is the identification slave unit, and host computer is visited first slave unit, if host computer has read correct identification code.Host computer redistributes the base address for this slave unit then.This slave unit is doing so that next slave unit is configured according to this sign, then to finish follow-up slave unit initial configuration with sign successively after the configuration in the signal of next stage transmission.
7, the work schedule of the utility model digital control system agreement
Round-robin sequential organization as shown in Figure 5, the byte that the reception of long data frame begins is 16 system data AA and BB, be the 0th byte (slave unit is numbered since 0) of the 0th equipment then, with No. 2 slave unit (physical address is 02) is example, transmit in the process of data in this slave unit transmission, the data volume when front transfer is counted.When counting down to 2*40+2=82 (52 HEX), begin to receive (duplicate, but transmit simultaneously) data, when counting down to 82+24=106 (6A HEX), stop to receive, beginning is transmitted while filling to the data stream padding data.When counting down to 106+24=138, self fill to transmit and finish, continue to transmit and transmit other device datas, finish up to data stream.
Main equipment sends the quick byte frame of one 8 byte then, and slave unit receives after the opening flag, begins counting; Receive in this byte frame the order data corresponding to own position, locking (enabling) long data frame passes the data of coming, and carries out corresponding operating.
Long data frame and fast frame operation all finish, and finish a circulation.
8, fault diagnosis and processing
The protocol definition of native system special data bit to the system power supply electric voltage exception, the scrambler broken string, link opens circuit, the communication data mistake, servomechanism installation is reported to the police, PLC reports to the police to wait all relevant detection and processing.
More than for realizing the host-host protocol of Design of CNC System of the present utility model; and finished the basic task of digital control system with this; the mode that realizes above-mentioned task can change as required, and protection domain of the present utility model is not limited on certain concrete numeral and the structure.Be provided with etc. and can be changed as the case may be as message structure, work schedule.But the one-piece construction of system can be referring to the implementation of following embodiment.
In addition, bus controller one end is provided with the interface that directly connects machine tool keyboard by transmission line.Machine tool keyboard is to control as a standard PLC equipment, follows the bus protocol that this digital control system is supported between the soft PLC supervisory routine of this PLC and numerical control software, can realize the lathe real-time Communication for Power by this bus controller.Because machine tool keyboard requires than higher response speed, therefore in number bus formula digital control system at having done particular design aspect this, for machine tool keyboard is reserved an independent bus interface, and the priority of the highest response that has been this Interface design and processing, thereby guarantee the real-time of the data interaction between machine tool keyboard and the host computer.
The above; it only is the preferable embodiment of the utility model; but protection domain of the present utility model is not limited thereto; anyly be familiar with those skilled in the art in the technical scope that the utility model discloses; be equal to replacement or change according to the technical solution of the utility model and utility model design thereof, all should be encompassed within the protection domain of the present utility model.
Claims (6)
1. a bus-type numerical control system comprises host computer (1), full digital servo-driver (3), motor (4) and programmable controller PLC that numerical control software is housed; Described host computer (1) and bus controller (2) constitute main equipment;
Described servo-driver (3) sends drive signal to described motor (4), and described motor (4) is sent the signal of position detecting device feedback back to described servo-driver (3) by circuit simultaneously; It is characterized in that:
Described main equipment be connected in series successively comprise described servo-driver (3) thereby, the slave unit of PLC and connect back main equipment and constitute a closed circuit; Link transmission data by being connected with transmission medium between described main equipment and the slave unit with Physical layer;
Wherein, described main equipment sends the main information relevant with all slave units to direct-connected first order slave unit with it; Described main information comprises command information, data message and triggers the exectorial information of certain one-level slave unit; And described main information will be according to the order that is connected in series slave unit one-way transmission successively to each slave unit;
Certain one-level slave unit receives, responds information associated in the described main information and provides feedback information; Described feedback information is transmitted back main equipment according to the unidirectional successively slave unit by each subordinate of the order of serial connection slave unit.
2. bus-type numerical control system according to claim 1 is characterized in that, the transmission medium of described Physical layer is selected ethernet physical layer or 1394 Physical layers or USB Physical layer for use.
3. bus-type numerical control system according to claim 2 is characterized in that the transmission medium of described Physical layer is selected ethernet physical layer for use.
4. bus-type numerical control system according to claim 3 is characterized in that, is occurring under the broken string situation, and slave unit transmits by the transmission line reverse data, thereby constitutes closed loop so that further fault handling with main equipment.
5. bus-type numerical control system according to claim 4 is characterized in that, described bus controller is provided with interface and directly connects machine tool keyboard by the link that is connected with transmission medium with Physical layer, and described host computer responds machine tool keyboard with limit priority.
6. according to the arbitrary described bus-type numerical control system of claim 1-5, it is characterized in that PLC function that the servo-driver of serial connection is integrated.
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| Application Number | Priority Date | Filing Date | Title |
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| CNU2007200101281U CN201035392Y (en) | 2007-01-15 | 2007-01-15 | Bus type numerical control system |
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| Application Number | Priority Date | Filing Date | Title |
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| CNU2007200101281U CN201035392Y (en) | 2007-01-15 | 2007-01-15 | Bus type numerical control system |
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| CN201035392Y true CN201035392Y (en) | 2008-03-12 |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102662330A (en) * | 2012-04-13 | 2012-09-12 | 哈尔滨工业大学 | Fault simulation device of fiber channel avionics environment (FC-AE)-1533 device |
| CN103376778A (en) * | 2012-04-17 | 2013-10-30 | 南京世泽科技有限公司 | Wireless control system for in-mine unmanned vehicle |
| CN104375461A (en) * | 2014-11-06 | 2015-02-25 | 威海华东数控股份有限公司 | Numerical control system and method for controlling two analog quantity spindles |
| CN105684361A (en) * | 2013-10-25 | 2016-06-15 | 艾摩罗那股份公司 | Bus system, and method for operating such a bus system |
| CN107831733A (en) * | 2017-11-11 | 2018-03-23 | 成都市龙泉星源机械厂 | A kind of combined numerically controlled system of turn-milling machine tool |
| CN112165423A (en) * | 2020-09-28 | 2021-01-01 | 北京东土科技股份有限公司 | Serial communication method, electronic equipment and storage medium |
| CN115135438A (en) * | 2021-01-27 | 2022-09-30 | 艾沛克斯品牌公司 | Spindle with logic power supply bus fault diagnosis device and spindle system |
-
2007
- 2007-01-15 CN CNU2007200101281U patent/CN201035392Y/en not_active Expired - Fee Related
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102662330A (en) * | 2012-04-13 | 2012-09-12 | 哈尔滨工业大学 | Fault simulation device of fiber channel avionics environment (FC-AE)-1533 device |
| CN102662330B (en) * | 2012-04-13 | 2014-04-02 | 哈尔滨工业大学 | Fault simulation device of fiber channel avionics environment (FC-AE)-1533 device |
| CN103376778A (en) * | 2012-04-17 | 2013-10-30 | 南京世泽科技有限公司 | Wireless control system for in-mine unmanned vehicle |
| CN105684361A (en) * | 2013-10-25 | 2016-06-15 | 艾摩罗那股份公司 | Bus system, and method for operating such a bus system |
| CN105684361B (en) * | 2013-10-25 | 2018-11-16 | 艾摩罗那股份公司 | bus system and method for operating such bus system |
| CN104375461A (en) * | 2014-11-06 | 2015-02-25 | 威海华东数控股份有限公司 | Numerical control system and method for controlling two analog quantity spindles |
| CN104375461B (en) * | 2014-11-06 | 2017-07-18 | 威海华东数控股份有限公司 | Digital control system and control method for controlling two analog quantity main shafts |
| CN107831733A (en) * | 2017-11-11 | 2018-03-23 | 成都市龙泉星源机械厂 | A kind of combined numerically controlled system of turn-milling machine tool |
| CN112165423A (en) * | 2020-09-28 | 2021-01-01 | 北京东土科技股份有限公司 | Serial communication method, electronic equipment and storage medium |
| CN115135438A (en) * | 2021-01-27 | 2022-09-30 | 艾沛克斯品牌公司 | Spindle with logic power supply bus fault diagnosis device and spindle system |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20080312 Termination date: 20140115 |