JP4144522B2 - Incremental linear scale position information communication data frame construction method - Google Patents

Description

  The present invention relates to a Z-phase information counting method and communication method in a format incremental linear scale.

There are the following methods for transmitting position information from a rotary encoder or linear scale to other devices.
Pulse wave system A-phase, B-phase, and Z-phase signals are respectively sent as rectangular waves.
The sin wave and cos waves are sent as analog signals instead of the sin wave system A phase and B phase signals. The communication system position information is converted into numerical values and transmitted by serial communication.
Of these, the pulse wave method and the sin wave method require wiring for each of the A-phase, B-phase, and Z-phase signals, but in the communication method, information can be transmitted with reduced wiring.
The position information of the communication system has a position information counter in the communication system, and when the position of the encoder or linear scale changes and one pulse is counted, the counter value is changed by one. (For example, refer to Patent Document 1.)
Japanese Patent Laid-Open No. 09-5114

  In the case of a rotary encoder, the Z-phase pulse is detected once in order to read the Z-phase pulse set on the rotating disk, so the upper limit of the counter value of the position information is set to a resolution of one round, and the Z-phase passes. The count value is reset to 0 each time. In this case, the Z-phase position of the rotary encoder can be determined by looking at the counter value, so only one counter is required.

  In the case of an absolute linear scale, the absolute position information of the linear scale is sensed, so only one position information counter is required.

  However, in the case of the incremental linear scale, since the position of the Z phase is set by an arbitrary position, setting interval, and number, there is a problem that it is not possible to cover up to the Z phase information with one position information counter.

The position information communication data frame configuration method according to claim 1 is provided with a Z-phase position information in addition to the position count information in an incremental linear scale that includes a plurality of Z phases in a linear scale and transmits position information by communication. A data frame to be transmitted is configured by a status field and a data field, and the status field is configured by providing Z phase detection frequency count information, an error status, and a Z phase detection flag between a start bit and a delimiter. The field is composed of position count information and Z-phase position information .
The position information communication data frame construction method according to claim 2 holds the value of the position counter synchronized with the Z phase detection timing every time the Z phase is detected, and transmits it together with the current position count value.
The position information communication data frame configuration method according to claim 3 resets the count value of the Z phase position information every time the Z phase is detected, and counts the number of pulses each time a linear scale pulse is detected, The correlation between the current position and the Z-phase position is detected.
According to a fourth aspect of the present invention, the location information communication data frame construction method transmits information on whether or not the first Z-phase has been detected since the power was turned on, using the Z-phase detection flag.

According to the position information communication data frame structure method of incremental linear scale according to claim 1, homing and Z-phase passage timing of the count and Z phase is control of utilizing the Z-phase signal in a device that uses a Linear Scale It can be used for the check function of the position count value.

According to the position information communication data frame configuration method of the incremental linear scale according to claim 2 , the position count value in the Z phase passed immediately before is held and transmitted together with the current position count value . It becomes possible to confirm the position count number between each Z phase, and when the distance between the Z phases and the count number are known, the comparison between the detected count number between the Z phases and the known distance matches It is possible to determine erroneous detection of the counter.

According to the incremental linear scale position information communication data frame configuration method of the third aspect, the method can be used for a process of changing the process for each fixed distance from the Z phase with each Z phase as a base point.

According to the incremental linear scale position information communication data frame configuration method according to claim 4, it is possible to check whether or not the first Z phase has been detected after the power is turned on by checking the Z phase detection flag. It can be determined whether the Z-phase count value is a value indicating the Z-phase. This makes it possible to determine whether or not the Z-phase count value can be used, and prevents misuse of the Z-phase count value.

In the incremental linear scale that includes a plurality of Z phases in a linear scale and transmits position information by communication, a data frame that transmits position information of Z phase in addition to position count information includes a status field and a data field. The status field is configured by providing the Z-phase detection count information, error status, and Z-phase detection flag between the start bit and the delimiter, and the data field includes the position count information and the Z-phase position. An incremental linear scale position information communication data frame construction method characterized by comprising information.

  In FIG. 1, a linear scale 1 has a Z-phase track 3 for detecting a Z-phase signal in addition to a position track 2 for detecting a position signal, a position counter 4 for counting the detected position signal, and a position when a Z-phase signal is generated. Position information of the linear scale 1 is held by the Z-phase counter 5 that holds the counter value. The linear scale 1 transmits information on the position counter 4 and the Z-phase counter 5 to other devices by a communication function. As shown in FIG. 2, the Z-phase counter 5 transfers the position count value of the position counter 4 in synchronization with the Z-phase detection timing 7 when the Z-phase signal has passed, and keeps the value until the next Z-phase signal is detected. Hold. 3 and 4, when the position is counted by operating in the reverse direction, the Z-phase counter 5 similarly holds the Z-phase count value until the next Z-phase signal is detected.

  Here, since the position cannot be managed immediately after the power is turned on, the value of the Z-phase counter 5 does not correctly indicate the Z-phase position before passing the position where the Z-phase signal is generated. For this reason, as shown in FIGS. 2 and 4, it is determined whether or not the Z phase has been passed once, and is reflected in the Z phase detection flag 8 at the first Z phase detection timing 7. By transmitting this to other devices by communication, the device that has received the communication determines whether the Z-phase has passed or has not been completed.

  The case where the Z phase track 3 has a plurality of Z phases will be described below. In this case, as shown in FIG. 2 and FIG. 4, the Z-phase detection number counter 9 is used to determine where the value of the Z-phase counter 5 that counts the Z-phase signal is information when the Z-phase signal is detected. Thus, counting is performed at every Z-phase detection timing 7.

  Since the absolute position is not managed, the position counter 4 is counted as 0 immediately after the power is turned on to create position information. However, depending on the device to be installed, there is a device origin (machine origin), which is linear at the machine origin. It may be preferred that the scale position count value be zero. For this reason, as shown in FIGS. 2 and 4, it has a function of performing a counter reset 10 of the position count value after activation, and performs a counter reset 10 when stopped by an input from a switch, a sensor, etc. The Z-phase detection flag 8 and the Z-phase detection frequency counter 9 are returned to their initial values.

  Hereinafter, only contents different from the first embodiment will be described in the second embodiment.

  As shown in FIG. 5, it has a position counter 4 and a Z-phase counter 5 that count position signals. The Z-phase counter 5 counts and holds the position signal in the Z-phase counter 5 every time it detects a position signal. The Z-phase counter 5 is reset in synchronization with the Z-phase detection timing 7 as shown in FIG. The count values of the position counter 4 and the Z-phase counter 5 are transmitted to other devices by communication.

  FIG. 7 shows an example of communication data 11 transmitted from the linear scale 1. Each information of the Z-phase detection flag 8 and the Z-phase detection frequency counter 9 is stored in the status field 12, and the position counter 4 and the Z-phase counter 5 are stored in the data field 13 and serialized to other devices at a time. Send.

  The incremental linear scale position information counting method of the present invention is useful for control using Z-phase information in an apparatus using the incremental linear scale.

Explanatory drawing which shows the correlation with the position of Z-phase and the position of a Z-phase, and a position counter in Example 1 of this invention (traveling direction +) Explanatory drawing of the transition of the count value along the time series of the Z-phase position counter in Embodiment 1 of the present invention (traveling direction +) Explanatory drawing which shows the correlation with the position of the Z-phase and Z-phase in Example 1 of this invention, and a position counter (traveling direction-) Explanatory drawing (movement direction-) of transition of the count value along the time series of the Z-phase position counter in Example 1 of this invention. Explanatory drawing which shows the correlation of the position of Z phase and Z phase position counter in Example 2 of this invention Explanatory drawing of transition of the count value along the time series of the Z phase position counter in Example 2 of this invention Explanatory drawing of the format in the linear scale communication data containing the Z phase position information in Example 3 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Linear scale 2 Position track 3 Z phase track 4 Position counter 5 Z phase counter 6 Position count upper limit 7 Z phase detection timing 8 Z phase detection flag 9 Z phase detection frequency counter 10 Counter reset 11 Communication data 12 Status field 13 Data field

Claims (4)

In an incremental linear scale that has a plurality of Z phases in a linear scale and transmits position information by communication, a data frame that transmits Z phase position information in addition to position count information is configured with a status field and a data field, The status field is configured by providing Z-phase detection count information, an error status, and a Z-phase detection flag between a start bit and a delimiter, and the data field is configured by position count information and Z-phase position information. location information the communication data frame structure method of incremental linear scale, characterized in that it has. Z-phase detection timing holds the value of the position counter in synchronism, positional information and communication data frame incremental linear scale according to 請 Motomeko 1 to transmit together with the current position count value each time it detects the Z phase Configuration method . Resets the count value of the position information in the Z-phase each time to detect the Z phase, by counting the number of pulses each time it detects a linear scale pulse, detects the correlation of the position of the current position and the Z-phase claims Item 4. A method of constructing an incremental linear scale position information communication data frame according to Item 1. Location information the communication data frame structure method of incremental linear scale according to claim 2 or claim 3 whether the information has been detected first Z phase after power-up for transmitting the Z-phase detection flag.

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