JPH02137964A - Origin position setting - Google Patents

Abstract

PURPOSE:To enable a detecting position of a detector to be easily accurately set by a method wherein when a specific exciting phase is excited, a relative position of a driven part and a detection means is so set that the driven part is positioned at a specific position. CONSTITUTION:In a typewriter in which an origin point of a step motor 4 is set as a D-A phase, when one cycle from a A-B phase to the D-A phase is taken as a detection range H, setting positions of a switch 10, i.e., a detector and a projection part 11 are so regulated that when either a B-C phase or a C-D phase within the detection range H is excited, the switch 10 is made to turn ON. Thereby, even through the setting position of the of the switch 10 is slightly shifted during service, since the A-B phase and the D-A phase exist on both sides thereof, timing when the switch 10 turns ON comes difficult to be outside the detection range. Therefore, even though the setting position of the switch 10 is shifted, only when timing of turning ON exists within detection range H, the origin position of a carriage 1 is determined at a position where the D-A phase of the detection range H was excited.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the assembly of a driven part driven by a step motor, and particularly to an origin position setting method for setting the origin position of a driven part in the assembly. Regarding.

[Prior Art] Conventionally, the movement position of a driven part driven by a step motor corresponds to the excitation phase of the step motor.
The moving position of the driven part has been controlled by changing the excitation phase of the step motor by a predetermined amount.

Further, in such a device, the moving position of the driven part is a relative position based on the origin position, so if the set position of the origin position shifts, the moving position also shifts. Therefore, the origin position of the driven part must be set accurately, and a detector for detecting the position of the driven part is provided at or near the origin position of the driven part. The origin position of the driven part is set each time the device is started, and furthermore, the accurate origin position can always be set by simply adjusting the detection position of the detector.

[Problems to be Solved by the Invention] However, there has been no effective means for accurately setting the detection position of the detector.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to enable the detection position of a detector to be set extremely easily and accurately.

[Means for Solving the Problems] In order to achieve this object, the present invention includes a driven part driven by the rotation of a step motor, and a detection means for detecting that the driven part is located at a predetermined position. A method for setting an origin position of a driven part of an electronic device, comprising: excitation means for exciting a predetermined excitation phase of a step motor; and a display section for displaying an excited excitation phase of the step motor; The present invention is characterized in that the relative positions of the driven part and the detection means are set so that when a predetermined excitation phase is excited by the excitation means, the driven part is located at a predetermined position.

[Operation] In the origin position setting method of the present invention having the above configuration, when a predetermined excitation phase of the step motor is excited by the excitation means, the step motor rotates by a predetermined number of steps, and the display section shows that the step motor is energized. The excitation phase is displayed. When a predetermined excitation phase is excited by the excitation means,
A relative position between the driven part and the detection means is set so that the driven part is located at a predetermined position.

[Example] Hereinafter, an example embodying the present invention will be described with reference to the drawings. In this embodiment, a case in which the method of the present invention is applied to setting the origin position of a carriage of a typewriter will be explained.

A type wheel, a printing hammer, an ink ribbon (not shown), etc. for printing are placed on the carriage 1. The carriage 1 is mounted so as to be able to reciprocate in the axial direction of a carriage guide shaft 2 provided parallel to a platen (not shown).
is fixed in the horizontal direction of the typewriter by a chassis 3 fixed to an outer frame (not shown) of the typewriter. A step motor 4 for driving the carriage is fixed within the typewriter so as to be located above one end of the carriage guide shaft 2, and the driving force of the step motor 4 is transmitted to the carriage 1 via a wire lobe 5. The wire lobe 5 is connected between a drive pulley 6 integrally formed with an intermediate gear 6a that meshes with the drive gear of the step motor 4, and a driven pulley 7 provided on the chassis 3 to which the other end of the carriage guide shaft 2 is fixed. wrapped around.

The carriage 1 is provided with a clasp 8 for coupling with a part of the wire row 15, and the clasp 8 is connected with a screw 9.
By tightening, the carriage 1 is fixed to a part of the wire lobe 5. Also, on carriage 1,
This is a detector for detecting the origin position of the carriage 1 on the typewriter, and is provided with a switch 10 constituted by a leaf switch. Furthermore, turn the switch 10 to
A protrusion 11 is fixed to the chassis 3 to which the pulley 7 is attached, and its position is opposite to the switch 10. When the carriage 1 moves to one end of the carriage guide shaft 2 on the side where the protrusion 11 is provided, the switch 10 is turned on by the protrusion 11. The switch 10 is fixed to the carriage 1 by a screw 12, and by loosening the screw 12 and changing the position of the switch 10, the timing at which the switch 10 is turned on by the protrusion 11 can be adjusted.

Here, excitation of the step motor 4 in which the present invention is implemented will be explained using FIG.

As shown in FIG. 3, the step motor 4 of the present invention has an A phase and a B phase, a B phase and a C phase, and a C phase and a D phase.

It is driven by a 2-2 phase excitation force type in which a set of two excitation phases, D phase and A phase, are sequentially and repeatedly excited. (Hereinafter, the excitation phase set of two phases, A phase and B phase, will be referred to as A-B phase, and the same shall apply to the others.) This step motor 4 is assembled into a typewriter,
Assume that the carriage 1 is set to be located at the origin position on the typewriter when the D-A phase of the step motor 4 is excited.

When the typewriter is powered on in this state, the coils of the step motor 4 are sequentially excited in a predetermined order, and the rotation is transmitted to the carriage 1 via the drive pulley 6 and wire lobe 5. moves toward the protrusion 11, and the protrusion 11 causes the switch 10 to move toward the protrusion 11.
is turned on.

If the D-A phase is not excited at this time, then
- The first D-A after the step motor 4 is further rotated to the position where the A phase is excited and the switch 10 is turned on.
The position where the phase is excited is set as the origin position of the step motor 4 and the carriage 1. Furthermore, if the D-A phase is excited when the switch 10 is turned on,
This position is set as the origin position of the step motor 4 and carriage 1.

In a typewriter in which the origin position of the step motor 4 is set to the D-A phase in this way, one cycle from the A-B phase to the D-A phase, including the D-A phase corresponding to the origin position. Assuming that the detection range H shown in FIG. The set position of the switch 10 is adjusted so that the switch 10 is turned on. As a result, even if the set position of the switch 10 is slightly shifted during use, the timing at which the switch 10 is turned on is unlikely to deviate from the detection range H because the A-B phase and the D-A phase are on both sides thereof. Therefore, even if the set position of the switch 10 deviates, as long as the ON timing is within the detection range H, the origin position of the carriage 1 is set at the location where the D-A phase of the detection range H is excited. It will be done.

Connected to the CPU 13 are a ROM 14 storing a program for controlling the typewriter, a step motor 4 for moving the carriage 1, a keyboard 15 and a switch 10 for detecting the origin position of the carriage 1.

Roughly, the CPU 13 includes a display area that displays which excitation phase of the step motor 4 is excited, and a display area that displays which excitation phase of the step motor 4 is excited, and the switch 1.
A display section 16 having a display area for displaying whether or not a predetermined position of the carriage 1 has been detected is connected thereto.

The CPU 13 is also equipped with a timer counter 17 for measuring elapsed time during program execution.

The origin position setting function of the present invention is not used during normal use. Therefore, in order to prevent the operator from easily switching to the mode for operating this function (hereinafter referred to as the origin position adjustment mode) due to an operator error, the key operation for switching to this origin position adjustment mode is Q. It is set to be switched only when three keys, ie, key 19, W key 20, and space key 21, are pressed at the same time and the B key 22 is also pressed.

In the origin position adjustment mode, the step motor 4 is
The space key 21 is used as a key for driving step by step and moving the carriage 1 toward the protrusion. A correction key 23 is also used as a key for moving one step in the opposite direction.

In addition, a plurality of display LEDs are provided in the display unit 16 to inform the operator which excitation phase of the step motor 4 is excited.
23 to 26 are provided. During normal use, this indicator LED is used to notify the operator that various functions provided on the typewriter have been executed. However, in the origin position adjustment mode, each display LE
D23 to D26 correspond to the A-B phase to the D-A phase, respectively, and light up when the corresponding excitation phase is excited.
It is possible for the operator to know which excitation phase is energized. Furthermore, when the switch 10 is turned on by the projection 11, the display LED 27 lights up, allowing the operator to know that the switch 10 has been turned on.

A method for setting the origin position of the carriage 1 of the typewriter of the present invention constructed as described above will be described below with reference to the flowcharts of FIGS. 6 and 7.

First, when the power to operate the typewriter is turned on, in step S1 (hereinafter, step S1 is written as 81), the Q key 19 and W key 20 on the keyboard 6 are pressed.
It is determined whether or not the space key 21 and the space key 21 are operated at the same time. If it is determined that the above three keys have not been operated, the carriage 1 is moved toward the protrusion 11 in S2. When the switch 10 is turned on by the projection 11, the step motor 4 rotates to a position where the CD phase is excited, and the CD phase is set as the origin position of motor control. In S3, normal motor drive control is performed based on this origin position.

Further, if it is determined that the Q key 19, W key 20, and space key 21 are operated at the same time in Sl, the process moves to S4. In S4, the timer counter 17 built in the CPUIB is set and starts counting. In S5, it is determined whether the B key 22 has been operated, and if it is determined that the B key 22 has not been operated, it is determined in S6 whether three seconds have elapsed since the timer counter 17 started counting. If it is determined that three seconds have elapsed, the process moves to S2 and the mode is converted to the normal use mode of the typewriter. If it is determined in S6 that 3 seconds have not elapsed, the process returns to 85 and this operation is repeated. If it is determined in S5 that the B key 22 has been operated, the process moves to S7 and the A-B phase of the step motor 4 is excited. At this time,
In the display section 16, the display LED 23 corresponding to the A-B phase is lit. Then, in S8, the mode of the typewriter is set to the origin position adjustment mode, and the process proceeds to an origin position adjustment routine in which the step motor 4 is driven one step at a time.

FIG. 7 is a flowchart showing this origin position adjustment routine.

First, in S9, a key input is waited for, and when a key is operated here, the process moves to S10. In SIO, it is determined whether the operated key is the space key 21 or not. If it is determined that the space key 21 has been operated, S
Move to ll. In S11, the carriage 1 is moved to the protrusion 1.
The step motor 4 is driven one step so as to move the step toward step 1, and the process moves to S14. Also, if it is determined in SIO that the space key 21 is not operated, S12
Move to. In S12, it is determined whether it is the operated key or the collection key 23.

If it is determined that the correction key 23 has not been operated, the process returns to 89. Further, when it is determined that the correction key 23 has been operated, the process moves to step 313, and the step motor 4 is moved in the opposite direction to the direction toward the protrusion 11.
Drive one step.

Then, in S14, the display LED corresponding to the excitation phase is
is lit. Next, when moving to 815, switch 10
It is determined whether or not it has hit the protrusion 11 and turned on.

If it is determined that the switch 10 is not turned on, the process returns to 89, and the above operations are repeated until it is determined that the switch 10 is turned on. When it is determined in S15 that the switch 10 has been turned on, the process moves to S16, and the display LED 27 that indicates that the switch 10 has hit the protrusion 11 is lit.

Therefore, in the origin position adjustment method of the present invention, it is desirable that the switch 10 of the step motor 4 is turned on when the B-C phase or the C-D phase is excited, as described above. The switch 10 is adjusted so that it is turned on when the phase or C-D phase is excited. For this,
First, operate the space key 21 to move the carriage 1 toward the protrusion 11, and confirm that the carriage 1 is located at the origin position when the D-A phase is excited.

If the carriage 1 is not located at the original position, the position fixed to the wire lobe 5 of the carriage 1 is adjusted so that the carriage 1 is located at the original position.

Next, the correction key 23 is operated to move the carriage 1 in the opposite direction until the B-C phase or the CD phase is excited. In this position, the switch 10 is connected to the protrusion 11.
Adjust the setting position of the switch 10 so that it is turned on. Since the switch 10 is adjustable and fixed on the carriage 1 by a screw 12, its position can be easily adjusted by loosening the screw 12 and changing the setting position of the switch 10. Further, in order to confirm that the adjustment has been performed accurately, the carriage 1 is moved in the opposite direction by a predetermined amount, and then the carriage 1 is moved again toward the protrusion 11 until the switch 10 is turned on. When the switch 10 hits the protrusion 11 and turns on, the display as described above is displayed and the ED 24 or 25 lights up, completing the adjustment of the origin position. Note that the origin position adjustment mode is canceled when the power is turned off.

[Effects of the Invention] As is clear from the detailed description above, according to the origin position setting method of the present invention, it is possible to accurately set the setting position of the detector that detects the origin position of the driven part or the vicinity thereof. Therefore, the origin position of the driven part determined by the detector can be determined accurately. In addition, in the origin position setting method of the present invention, when the adjustment means for adjusting the set position of the detector is built into the target device, the origin position is set to be adjusted by simple operations such as mode conversion. It becomes possible. Therefore, the adjustment can be made easily without using any special equipment required for the adjustment.

[Brief explanation of the drawing]

1 to 7 show embodiments embodying the present invention. FIG. 1 is a perspective view of the main parts showing an outline of the carriage drive mechanism, and FIG. 2 is a plan view of the main parts of the carriage drive mechanism. ,
Fig. 3 is an explanatory diagram for explaining the excitation method of the step motor, Fig. 4 is a block diagram showing the structure of the typewriter,
FIG. 5 is a plan view showing the keyboard portion of the typewriter, and FIGS. 6 and 7 are flow charts for explaining the operation of the typewriter of the present invention. In the figure, 1 is a carriage, 4 is a step motor, 10 is a switch, 11 is a projection, 15 is a keyboard, and 16 is a display section.

Claims (1)

[Claims] 1. An electronic device comprising a step motor, a driven part driven by the rotation of the step motor, and a detection means for detecting that the driven part is located at a predetermined position. A method for setting an origin position of a drive unit, comprising: excitation means for exciting a predetermined excitation phase of the step motor; and a display section for displaying an excited excitation phase of the step motor; A method for setting an origin position, comprising setting the relative position of the driven part and the detection means so that the driven part is located at a predetermined position when a phase is excited.