JPS61277471A - Type wheel type printer - Google Patents

Abstract

PURPOSE:To enable an abnormal rotation of a type wheel to be securely detected, by a system wherein during the time when a plurality of type wheels are rotated a predetermined angle from an initial position, it is detected by a photosensor whether two through-holes provided in each of the type wheels are communicated with each other. CONSTITUTION:When each of the type wheels 1-1-1-n is located at the initial position, the through-holes 21, 22 provided in each of the type wheels are communicated with each other in line, so that light from a light emitter 11a of a transmission type photosensor 11 passes through the through-holes 21 to be received by a light receiver 11b, an initial position return discriminating circuit 13 discriminates the returning to the initial position of each of the type wheels on the basis of a signal S2 from a detecting circuit 12, and an abnormality discrimination signal S8 is not outputted from a rotation abnormality discriminating circuit 17. After a printing operation is started, the through-holes 21, 22 are moved in the mutually communicated condition until the rotation of the type wheels is stopped by the first type- selecting piece, and when the type wheels are rotated by a predetermined angle, the through- holes 22 come to a position in registration with the photosensor 11. At this moment, when abnormal rotation is present in one of the type wheels, the light receiver 11b does not receive light, and the circuit 17 outputs the signal S8. Accordingly, misprinting can be prevented from occurring.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a type wheel type printing device which rotates and positions a plurality of type wheels to select and print required type.
In particular, the present invention relates to a type wheel type printing device that is capable of completely and accurately detecting abnormal rotation of the type wheel.

(Prior Art) Type wheel type printing devices conventionally used in automatic ticket vending machines and the like are equipped with a plurality of type wheels in order to print a plurality of digits.

Conventionally, the printing mechanism of this type wheel type printing device was
For example, the structure is as shown in FIGS. 4 and 6.

In the type wheel 1, a plurality of printing surfaces 8 of different symbols and characters are arranged in a row at equal intervals in the circumferential direction on the outer periphery of a disk-shaped base 2. Notches (selection notch 8 and stop notch 9) are provided in a protruding manner corresponding to the arrangement spacing.

The type wheel 1 having such a structure is in charge of printing for -digits,
Type wheels 1-1 to 1-n (n is a natural number) corresponding to the number of digits required for printing are mounted on one rotating shaft 4.

Each type ring 1-1 to 1-n is rotatably attached to a rotating shaft 4, and a clutch pawl 7 provided near the axis of the base 2 is attached to a part of the outer periphery of the rotating shaft 4. By fitting into the formed groove 4a, the rotating shaft 4 and the type wheels 1-1 to 1
-n is adapted to engage.

Further, above each type wheel 1-1 to 1-H, a type selection strip 5 (
5-1 to 5-n) are arranged, and when the type selection strip 5 is dropped downward, the selection notch 8 is
Since it comes into contact with the type selection strip 6, the type wheel 1 cannot rotate in the direction of arrow A in FIG. In this state, when the rotating shaft 4 rotates in the direction indicated by the arrow, the clutch pawl 7 comes off from the groove 4a because one wall 4b of the groove 4a is rounded, and the rotating shaft 4 is prevented from rotating. It won't happen.

Seven hooks 6 are arranged above each of the type wheels 1-1 to 1-H (not shown in FIG. 5), and the rotating shaft and the type ring rotate in the direction B, and the hooks 6 The contact of the stop notch 9 stops the rotation of the type wheel. The position where the stop notch 9 comes into contact with this hook 6 is 1 type wheel 1-1 to 1
The set position of the hook 6 is determined so as to be at the initial position of -H.

Although not shown, a motor for rotating the rotary shaft 4 is provided, and a controller for controlling the drive of this motor and the type selection strip 5 is also provided. , an encoder is attached, and is configured to detect the rotation angle of the rotary shaft 4 and feed it back to the controller.

The printing operation of such a printing apparatus is performed as follows.

All the type wheels 1-1 to 1-n, before starting the printing operation,
It is set to the initial position.

With the start of the printing operation, when the rotating shaft 4 rotates in the direction of the arrow in Figure tJ4, all the type wheels 1-1 to 1-n simultaneously rotate in the direction of the arrow as the rotating shaft 4 rotates. .

When the type to be printed comes to the printing position, the type selecting strips 5-1 to 5-2 are individually dropped to stop the type to be printed at the full degree printing position.

When all the type is arranged, the ink ribbon and printing paper placed at the printing position are hit with a hammer to the printing surface to print.

When printing is completed, the rotating shaft 4 moves in the direction of arrow B in Fig. 4 (
The rotation in this direction is referred to as "reverse rotation"), and all the type wheels 1-1 to 1-n return to their initial positions.

The above operation is regarded as one cycle of the printing operation, and when the number of lines to be printed is plural, the above-mentioned printing operation cycle is repeated by the number of lines to be printed.

(Problems to be Solved by the Invention) However, the conventional type wheel type printing device described above detects the rotation angle of the rotary shaft 4 and performs feedback control of the rotational positioning operation of the C1 type wheels 1-1 to 1-H. For example, if the clutch pawl or spring a were damaged, the printing wheel 1 would be able to completely rotate freely around the rotating shaft 4, so the rotating shaft 4 would not be in its initial position. Even if the printing wheel 1 returns to the original position, the printing wheel 1 is not always at the initial position, and since there is no means to detect this abnormality in advance, there is a risk of printing errors.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a type wheel type printing device as described above, in which each type wheel is Two or more through-holes are formed that extend through the base in a straight line in the direction of the rotational axis, and when each type ring is in its initial position, it faces both ends of one of the plurality of through-holes. A transmission type optical sensor is disposed, further comprising a light reception determining means for determining whether or not a light receiver of the transmission type optical sensor receives light from the projector; Later, when the light reception determining means does not determine even once that light transmitted through the penetrating light has been received during rotation by a predetermined angle, it is determined that an abnormality has occurred in the rotation of the type wheel. The present invention is characterized in that it is provided with a rotation abnormality determining means for determining.

(effect) At least, if the rotation of the type wheel is all normal.

During the initial position and the rotation of one print surface from the initial position, all the type wheels rotate at the same angle as one, so within this period, the plurality of through holes are
It should be communicating. Therefore, within this period, the light from the light projector of the transmission type optical sensor is transmitted through each through hole.
When passing in front of the emitter, it always reaches the receiver.

On the other hand, if any rotational abnormality occurs in any one of the type wheels, the through hole is blocked and the light from the projector is no longer transmitted. Therefore, the rotational abnormality determining means determines that a rotational abnormality of the type wheel has occurred when it is detected that the light that should be transmitted through the through-hole is not transmitted even once within the above-mentioned period.

With such an effect, abnormal rotation of the type wheel can be accurately detected, and erroneous printing can be prevented.

(Example) The configuration of one embodiment of the present invention is shown in FIG.

The structure of the printing mechanism in this embodiment is shown in FIGS. 4 and 5 above.
The structure is almost the same as that of the conventional example shown in the figure, and the difference is that two through holes 21 and 22 are provided in each type ring l-1-1.
- Holes are formed in the base of H in the direction of the rotation axis.

As shown in FIG. 2, these through-holes 2L and 2B are spaced apart by an angle θ which is smaller than one rotation angle θ of the printing surface 8 and close to θ.

When all the type wheels 1-1 to 1-n are in the initial position, the holes formed in each of the type wheels 1-1 to 1-H are aligned in the direction of the rotation axis, and two through holes are formed. 21.22.

Transmissive optical sensors 11 are disposed so as to face both ends of the through hole 21 when the respective type wheels l-1-1-n are all at their initial positions.

The output signal S of this transmission type optical sensor 11 (light receiver 11
b) is input to the light reception detection circuit 12.
ing.

Based on the output signal S1 of the transmissive optical sensor 11, the light reception detection circuit 12 generates a signal (for example,
This is a circuit that outputs a high level signal. The output signal S of the light reception detection circuit 12 is inputted to the initial position return determination circuit 18 and the rotation abnormality detection circuit 1.

The rotational position detection circuit 14 is based on an output signal S of an encoder (using an optical rotary encoder, etc.) 21 attached to the rotating shaft 4 on which each of the type wheels 1-1 to 1-n is mounted. Then, the relative angular position of the rotating shaft 4 with respect to the initial position is determined (for example, it is composed of a circuit that counts the number of pulses output from an encoder).

The rotation start determination circuit 15 detects that the rotation shaft 4 has started rotating from the initial position based on the signal S representing the rotation position of the rotation shaft 4 output from the rotation position detection circuit 14, and also detects the rotation start of the rotation shaft 4 from the initial position. It is detected that the rotating shaft 4 has rotated by a predetermined angle (this angle is set to the angle θ for one printing surface) from the time when the rotation start is detected. For example, the apparatus is configured to output a high-level signal as the output signal S for a period from the start of rotation of the rotary shaft to the time of rotation at a predetermined angle (hereinafter referred to as "abnormality check period").

The initial position detection circuit 16 detects that the rotational position of the rotating shaft 4 is at the initial position based on the output signal S of the rotational position detection circuit 14, and uses a signal S6 indicating this to determine whether the rotational position is returned to the initial position. Supplied to circuit 13.

The initial position return determination circuit 18 includes the initial position detection circuit 1
6 detects that the rotating shaft 4 is at the initial position, the light reception detection circuit 12 detects that the light receiver 11
This is a circuit that determines whether or not light is being received at the light receiver 11b when the rotating shaft 4 is at the initial position.
It is determined that an abnormality has occurred in the rotation of H, and a signal S (hereinafter referred to as "abnormality determination signal") representing this fact is output.

゛The rotation abnormality determination circuit 1f is the rotation start determination circuit 15.
A circuit that determines whether or not a signal indicating that light has been received by the light receiver 11b is input from the light reception detection circuit 12 while the signal S input from the light receiver 11b is a signal representing an abnormality check period. Ah, within the abnormality check period, receiver 1
When a signal indicating that light has been received is not inputted at 1b, it is determined that a rotation abnormality has occurred in the type wheels 1-1 to 1-H, and a signal (abnormality determination signal) S8 representing this fact is output.

b. Initial position return determination circuit 18 and rotation abnormality determination circuit 17
The abnormality determination signal S and 88 output from the alarm circuit 1
8 and is input to the motor stop circuit 19. The alarm circuit 18 is a circuit that generates an alarm when any one of the above-mentioned abnormality determination signals 81 m and $11 is input, and the motor stop circuit 19 is a circuit that generates an alarm when any one of the above-mentioned abnormality determination signals S,
, S8, the rotation axis 4 is input.
This circuit stops the operation of the motor 20 that rotates the motor 20.

Next, the operation of this embodiment will be explained.

First, if the rotation of each type wheel 1-1 to 1-n is normal, all type wheels 1-1 to 1-n are at the initial position before the printing operation is started. It is set.

In this state, the two through holes! 1.22 is.

Since both pass through in a straight line, 1, the light emitted from the light projector 11a of the transmission type optical sensor 11 passes through the through hole 21 and enters the light receiver 11b.

Therefore, the signal S output from the light reception detection circuit 12 is:
This becomes a □ signal indicating that the light has been received by the light receiver 11b, and the initial position return determination circuit 13 outputs a □ signal indicating that the light has been received by the light receiver 11b.
It is determined that all of 1 to 1-n have returned to their initial positions normally, and an abnormality determination signal S is generated.

is not output. Further, the abnormality determination signal S is not outputted from the rotation abnormality determination circuit 17 either.

Then, when the printing operation is started, while the rotating shaft 4 rotates by θ, all of the type wheels are connected to the type selection strips 5-1 to 5-5.
Since the rotation is not stopped by -H, the two through holes 21 and 22 will continue to move in the penetrating state.

Therefore, when the type wheels 1-1 to l-n are rotated by the constant angle θ from the initial position, the transmission type optical sensor 11
Since the through hole 22 is located between the light receivers 11a and llb,
Light emitted from the light projector 11a passes through the through hole z2 and enters the light receiver 11b.

As a result, the output signal S of the light reception detection circuit 12 is a signal indicating that light has been received by the light receiver 11b.The abnormality determination circuit 1? , within the abnormality check period,
After the light is received by the light receiver 11b, a controller (not shown) selects the printing surface of the type wheels 1-1 to l-H, and after printing, all the type wheels are returned to their initial positions. be returned to.

Next, any one of the type wheels 1-1 to 1-n or 21
The above describes the case where rotation abnormality occurs.

For example, if the clutch pawl or spring 7a is damaged, 1. It is assumed that one of the type wheels (which is referred to as 1-m (m is a natural number equal to or less than n)) is in a state where it can completely freely rotate around the rotation axis base.

In this case, the malfunctioning type wheel 1-m is connected to the rotary shaft 4
As a result, during the abnormality check period, the through holes 21 and 22 are blocked at the failed type wheel 1-m, and the light emitted from the projector 11a is transmitted through the through holes 22 and 22. cannot be passed through.

Therefore, the rotation abnormality determination circuit 17 outputs the abnormality determination signal S8 because it does not receive light from the light reception detection circuit 12 during the abnormality check period. As a result, the motor 20 stops, and an alarm is issued to notify that an abnormal rotation has occurred.

Furthermore, when the type wheels 1-1 to 1-n are returned to their initial positions, the initial position return determination circuit 18 performs an operation to detect abnormal rotation of the type wheels. That is, when the printing operation is completed and the type wheels 1-1 to 1-n are returned to their initial positions, the failed type wheel 1-m cannot follow the rotation of the rotary shaft 4. The through holes 21,22 become discontinuous.

Therefore, even though the rotating shaft 4 is at the initial position, the light receiver 11b does not receive light, and as a result, the abnormality determination signal S is output from the initial position return determination circuit 18.

Here, the reason why two through holes are provided is that, for example, if a through hole is provided only at a position where light from the projector 11a passes through at the initial position (that is, if only the through hole 21 is provided), a failure may occur. Even if the type wheels 1-m are free to rotate around the rotating shaft 4, the failed type wheels 1-m rotate due to friction between the type wheels 1-IN1-n.

Therefore, when returning the type wheel 1-INl-n to its initial position, the rotary shaft 4 is rotating for a long time, so friction between the type wheels causes the failed type wheel 1-m to It may return to the initial position. In this case,
This means that rotation abnormality cannot be detected.

On the other hand, as in this embodiment, there are two through holes! 1.2
2, even if rotational abnormality detection fails at the initial position as described above, rotational abnormality can be reliably detected the next time a printing operation is started.

In addition, if the number of through holes is further increased, the accuracy of rotation abnormality detection can be further improved. Needless to say, it can be replaced with .

(Effects of the Invention) As described above in detail, the present invention provides two paths for through-holes that pass through the base of each type wheel in a straight line in the direction of the rotation axis when all of the plurality of type wheels are in the initial position. By forming the above, and detecting whether or not the through-hole is in a communicating state while the type wheel rotates by a predetermined angle after starting rotation from the initial position, using a transmission type optical sensor, Abnormal rotation of the type wheel can be detected reliably, and erroneous printing can be prevented.

[Brief explanation of drawings]

Fig. 1 is a block diagram of an embodiment of the present invention, Fig. 2 is a side view of a type ring in the same embodiment, Fig. 8 is a diagram showing the arrangement of the type ring and a transmission type optical sensor, and Fig. 4 is a diagram showing the arrangement of the type ring and a transmission type optical sensor. FIG. 5 is a side view showing a conventional type wheel, and FIG. 5 is a front view of the same type wheel. 1... Type wheel 1-1 to 1-n... Type wheel 2... Base 2-1 to n...
Substrate 8, printing surface 4...rotation axis). 5t...-Type selection section 7...Clutch pawl a...Spring 8...Selection notch 1
1... Transmissive optical sensor lla... Floodlight 11
b... Light receiver 12... Light reception detection circuit (light reception determination means) 18... Initial position return determination circuit 14... Rotation position detection circuit 16... Initial position detection circuit 17... Rotation abnormality detection Circuit (rotation abnormality determination means) 21
,! ...Through hole patent applicant Nippon Daughter Co., Ltd. Figure 1 Figure 2

Claims (1)

[Claims] 1. A plurality of type wheels having a plurality of printing surfaces arranged circumferentially around the outer periphery of a disc-shaped base are mounted on a single rotating shaft, and the plurality of type wheels are rotated from an initial position. In a type wheel type printing device that selectively prints so that the printing surface to be printed is lined up in a line in the direction of the rotation axis by rotating each type wheel simultaneously around the rotation axis and stopping the rotation of each type wheel individually as appropriate. , when each of the type wheels are all in the initial position, two or more through holes are provided that penetrate in a straight line in the direction of the rotational axis within each of the type wheels, and when all of the type wheels are in the initial position, A transmission type optical sensor disposed to face both ends of one of the plurality of through holes, and a light reception determining means for determining whether light from the projector is received by the light receiver of the transmission type optical sensor. and, when the light reception determining means does not determine that light transmitted through the penetrating light has been received at least once while each of the type wheels rotates by a predetermined angle after the rotation starts from the initial position. A type wheel type printing device, further comprising rotation abnormality determining means for determining that an abnormality has occurred in the rotation of the type wheel.