JPS62119086A - drive device - Google Patents

Abstract

PURPOSE:To make it possible to also use a drive apparatus as an alarm sound generating means and to avoid the scale-up of machinery and cost increase, by alternately rotating a motor to positive and reverse directions at a minute time interval at the time of abnormality for generation of vibration sound. CONSTITUTION:When a figure or a shape is printed graphically by a printing head 6, the temp. of the printing head 6 is often abnormally rising. Hereupon, when the temp. of the printing head 6 detected by a temp. sensor 23 rose to set temp. T0 or more, a drive motor 12 repeats positive and reverse rotations, for example, 400 times (for about 3-4sec) by three steps at a minute time interval. As a result, each part of a transmission mechanism vibrates at a high speed to generate vibration sound from each part and said vibration sound is synthesized to form vibration sound having a sufficient sound pressure level and, therefore, this sound is put to practical use as alarm sound.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a drive device driven by a motor, and in particular, when an abnormality occurs in a device incorporating this drive device, the motor is alternately rotated forward and backward at minute intervals. This invention relates to a system in which an alarm sound is generated from a transmission mechanism driven by a motor when the transmission mechanism is reversed.

(Prior art) In general, in industrial machinery that has complex mechanisms and performs complicated control, abnormalities in each part can be detected because abnormalities in each part can cause significant economic losses. Sensors are installed, and when an abnormality occurs, an alarm is issued by a warning lamp or alarm buzzer, or displayed on an alarm display.

(Problem to be solved by the invention) The above industrial machinery can secure enough space to incorporate sensors and alarm display means, and the cost of sensors and alarm display means can be reduced from the total manufacturing cost. Since it is very small,
No particular problem arises by incorporating them.

However, although non-industrial equipment is required to be particularly small, lightweight, and inexpensive, incorporating the above warning display means increases the size of the equipment, increases costs, and increases customer demand. The problem is that it no longer matches the needs.

The present invention attempts to utilize a drive device in which a driven body is driven by a motor via a transmission mechanism as an alarm sound generating means.

(Means for Solving the Problems) A drive device according to the present invention is a drive device that transmits the rotation of a motor to a driven body via a transmission mechanism and drives the driven body, and A control means is provided for reversing the drive current to the motor, and the motor is alternately rotated forward and reverse at minute intervals, thereby causing the transmission mechanism to generate an alarm sound.

(Function) Since the drive device according to the present invention is configured as described above,
When the motor is rotated forward and reverse alternately at minute intervals, each part that makes up the transmission mechanism begins to vibrate at a high frequency, and each part generates vibration noise at an audible sound pressure level. This vibration sound can be used as an alarm sound.

(Example) Embodiments of the present invention will be described below with reference to the drawings.

In this embodiment, the present invention is applied to a drive device for driving a carriage body 4 of a thermal printer, as shown in FIG.

A platen 2 extending in the left-right direction is disposed within the frame (path shown) of the thermal printer, and a support shaft 3 extending in the left-right direction parallel to the platen 2 is provided.
The carriage body 4 is movably supported, and the lower surface of the front end of the carriage body 4 is connected to a guide member (path shown).
is supported by

A head carriage 5 is rotatably supported at the front end of the support shaft 3, and a print head 6 facing the platen 2 is provided on the upper surface of the head carriage 5.

Here, a drive device for reciprocating the carriage body 4 left and right along the support shaft 3 is configured as follows.

A loop-shaped drive belt 7 made of a timing belt is disposed parallel to the spindle 3, passes through the inside of the carriage body 4, and is hung over the idle pulley 8 and the drive pulley 9. A drive belt 7 on the side of the print head 6 is fixed to the carriage body 4.

A synthetic resin driven gear 10 is fixed to a pivot shaft 11 to which the driving pulley 9 is fixed, so that the driven gear 10 and the driving pulley 9 can rotate together.

Further, the drive motor 12 consisting of a step motor is arranged such that its output shaft 12a is parallel to the pivot shaft 11, and the output shaft 12a has a drive gear made of synthetic resin that meshes with the driven gear 10. 13 is fixed.

The drive motor 12 is controlled by a control device C, which will be described later. When the drive motor 12 rotates counterclockwise, the drive boot +79 rotates clockwise via a gear transmission mechanism consisting of a drive gear 13 and a driven gear 10. However, when the carriage body 4 is driven to the right along the support shaft 3 via the drive belt 7 and the drive motor 12 is rotated clockwise, the carriage body 4 is driven to the left. There is.

A temperature sensor 23 for detecting the temperature of the print head 6 is attached near the print head 16, and a detection signal from the temperature sensor 23 is output to a control circuit C of the printer.

Note that 14 is a paper feed roller, 15 is a ribbon cassette, and 16 is a thermal transfer ribbon.

When the print head 6 is used to graphically print figures, shapes, etc., the temperature of the print head 6 may rise abnormally.

Therefore, when the temperature detected by the temperature sensor 23 rises above a predetermined set temperature T0, the drive gear 13, the driven gear 10, the drive belt 7 and This is intended to utilize a drive device including a transmission mechanism consisting of an idle pulley 8 and a drive motor 12. This will be explained in detail below.

For example, as shown in the block diagram of FIG. 2, the control device C includes an input interface 18 that receives output signals from an external electronic device 17 and a temperature sensor 23, a CPU 19 (central processing unit), and a ROM 21 (read-only). memory)
, a RAM 22 (random access memory), a driver circuit 20 that receives output from the CPU 19 , a paper feed motor of a paper feed mechanism, and a print head 6 .

The external electronic device 17 corresponds to a typewriter, computer, word processor, etc., and controls the drive motor 12, paper feed motor, and print head 6 based on various control command signals from the external electronic device 17. The control program to control and the character data for driving the print head 6 in accordance with the print character code from the external electronic device 17 are inputted and stored in the ROM 21 in advance.
Since these are similar to existing thermal printers, detailed explanations will be omitted.

The detection signal from the temperature sensor 23 is output to the input interface 18, and the input interface 18 outputs the detection signal to the input interface 18.
The following control routine is executed in the control device C based on this detection signal, and when the temperature of the print head 6 abnormally rises, the drive motor 12 is controlled and an alarm sound is emitted from the transmission mechanism. .

The control program for the control routine described below is input and stored in the ROM 21 in advance, and
The data processed in step 9 is stored in the RAM 22 as necessary.
is temporarily stored.

FIG. 3 shows a schematic flowchart of a control routine for generating the above-mentioned alarm sound.

In step S1, a control routine is started when the printer is started, and in step S2, the detected temperature T is read from the temperature sensor 23, and in step S3, the detected temperature T exceeds the set temperature To (however, this is a ROM constant). If T≧T0 is not reached, the process returns to step S2, and if the temperature of the print head 6 abnormally rises and becomes T≧T0, the process proceeds to step S4. In step S4, the counter 1=1, in step S5 the drive motor 12 is driven three steps clockwise in FIG. 1, in step S6 the drive motor 12 is driven three steps counterclockwise, and in step S7 It is determined whether the counter ■ is I=400 or not, and if it is not I=400, the process moves to step S8, and the counter I is counted up in step S8.
Step S8 moves to step S5, and step S5
- Step S6 - Step S7 are repeated, and the counter ■
When becomes 1-400, the process moves from step S7 to step S9 and ends.

That is, when the temperature of the print head 6 detected by the temperature sensor 23 rises above the set temperature T0, the drive motor 12 rotates forward and reverse in 3 steps at minute intervals, for example, 400 times (for about 3 to 4 seconds). ) is designed to repeat.

When the drive motor 12 vibrates at high speed as described above, the vibration causes the drive gear 13 and driven gear 10 to vibrate at high speed, and furthermore, the drive belt 7 and carriage body 4 also vibrate at high speed.

When each part of the transmission mechanism vibrates at high speed in this manner, vibration sounds are generated from each part, which are combined to form a vibration sound with a sufficient sound pressure level, which can be used as an alarm sound.

It goes without saying that the closer the frequency of vibration when the drive motor 12 is rotated forward and backward to the natural frequency of the vibration system of the transmission mechanism, the more intense the vibrations and the stronger the vibration noise will be.

In particular, the frictional noise and collision noise caused by the vibration of the gear transmission mechanism consisting of the driving gear 13 and the driven gear 10 are strong.
Since the vibration noise accounts for most of the vibration noise, the present invention can be similarly applied to drive devices that drive a driven body through a gear transmission mechanism using various types of motors. A drive device driven by a motor other than the motor may also be used.

In the above embodiment, an alarm is given for an abnormal rise in the temperature of the print head 6, but it goes without saying that the present invention can be used to issue an alarm for various kinds of abnormalities depending on the equipment to which the present invention is applied.

(Effects of the Invention) According to the drive device according to the present invention, as explained above, the alarm sound is generated from the transmission mechanism by alternately rotating the motor forward and reverse at minute intervals, so the drive device can also be used as an alarm sound generating means.

As a result, an alarm display function can be provided without increasing the size and cost of the device.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention. Fig. 1 is a plan view of the main parts of a thermal printer, Fig. 2 is a block diagram of the thermal printer control device and its peripheral equipment, and Fig. 3 shows an abnormality in the print head. 2 is a schematic flowchart of a control routine for generating an alarm sound when the temperature rises. 4. Carriage body, 7. Drive belt, 8.
Idle pulley, 9. Drive pulley, 10. Driven gear, 12. Drive motor, 13. Drive gear.
18...Input interface, 19...CPU
, 20...Driver circuit, 21...ROM,
22...RAM. C...control circuit. Patent applicant: Brother Industries, Ltd. Figure 3

Claims (1)

[Claims] (1) In a drive device that transmits the rotation of a motor to a driven object via a transmission mechanism and drives the driven object, a control means is provided to reverse the drive current to the motor at minute intervals, and A drive device characterized in that an alarm sound is generated from a transmission mechanism by alternately rotating a motor forward and reverse.