JPH0442746A - Motor provided with encoder for recorder - Google Patents

Abstract

PURPOSE:To prevent contamination due to dust or ink droplet and to stabilize the rotation of motor by disposing an encoder at the outside of a motor case and fixing a dust-proof cover, covering the encoder, to the motor case. CONSTITUTION:A encoder 31 is fixed at the outside of a motor case 10 located oppositely to the output side of a motor. A dust-proof cover 36 covering the encoder 31 is fixed detachably to the outer circumference of the motor case 10. Consequently, foreign matters such as paper powder or ink mist generated in a recorder can be prevented from adhering to an encoded disc 32 or a sensor 33 even if the motor is mounted in the recorder, and error or instability in the positional control of recording head or material to be recorded due to detection miss such as passing of code on the encoder 31 caused by adhesion of foreign matter can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a dust-proof structure for a motor with an encoder used in a recording device having an image forming function such as a facsimile, a copying machine, and a printer.

(Prior Art) Recording devices (devices with recording means) such as printers, copiers, and facsimiles record images on recording materials such as paper and thin plastic plates based on image information. It is configured.

The recording device may be an inkjet type,
It can be divided into wire dot type, thermal type, laser beam type, etc.

The recording apparatuses include a serial scan type that uses a recording head mounted on a carriage that moves along the recording material, and a line type recording that uses a line recording head that covers almost the entire width of the recording material. It can be broadly divided into equipment.

In the above-mentioned recording apparatus, several motors are used as drive sources for each operating part, and for example, the recording material is transported (
A paper feed motor for paper feeding), a carriage motor for driving the carriage, a recovery motor for driving a recovery system in the case of an inkjet recording apparatus, etc. are used.

These motors generally have a rotating position! Stepping motors are widely used because of their excellent controllability of rotational speed.

The carriage motor is a motor that regulates the recording position, and the transport motor is a motor that regulates the position (or feeding amount) of the recording material, and the rotational operation of these motors directly affects the quality of the recorded image. Therefore, stable and high rotation accuracy is required.

Therefore, as a method of increasing the rotational accuracy of the motor, a method has been implemented in which an encoder is used and the motor is feedback-controlled based on motor rotational position information provided by the encoder.

This encoder consists of a coding disk fixed to the motor shaft and a sensor that detects the passage of the code by rotation.For example, a slit disk and a photointerrupter
There are light transmissive types consisting of a striped disk, light reflective types consisting of a striped disk and a light emitting/receiving element, and magnetic sensing types.

In conventional encoder-equipped motors, the encoder is built into the motor case.

With such a structure in which the motor is assembled into the motor case, it is difficult to ensure the versatility of the motor, and the assembly process is complicated.

On the other hand, in a recording apparatus, dust including paper dust from a recording material such as paper may be generated, and in the case of an inkjet recording apparatus, ink mist may be generated.

[Technical problem to be solved by the invention] Therefore, in order to ensure the versatility of the motor and to simplify the assembly process, it is possible to assemble the encoder outside the motor case and use it as a motor for a recording device. In this case, there is a problem in that the coding disk or the sensor is contaminated by the paper dust, ink mist, etc., and the detection of the code is omitted, which disturbs the accuracy of detecting the rotation of the motor or makes it inaccurate.

In particular, the position of the carriage driven by the carriage motor is related to the recording position, and the rotational position of the paper feed roller driven by the transport motor is related to the feeding amount of the recording material. If a detection error occurs, it becomes impossible to maintain the image quality of the recorded image.

The present invention has been made in view of such conventional technical problems, and provides a recording device for use in a recording device that can prevent contamination due to dust, ink droplets, etc., and can maintain stable motor rotation with high precision. The purpose is to provide a motor with an encoder.

[Means for solving problems]

The present invention provides a motor with an encoder used in a recording device that forms an image on a recording material based on image information, in which the encoder is disposed outside a motor case, and a dustproof cover is provided to cover the encoder. By attaching the motor to the motor case, it is possible to prevent contamination by dust, ink droplets, etc., and to provide a motor with an encoder for a recording device that can stably maintain motor rotation with high precision. .

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 7 is a schematic perspective view showing the main part configuration of a recording apparatus equipped with an encoder-equipped motor according to the present invention.

In FIG. 7, 61 is a head unit mounted on a carriage 63, and the head unit 6I includes a plurality of (four in the illustrated example) recording disks 62A, 62B,
It has 62C and 62D.

A plurality of ejection ports are formed in a predetermined array on the ejection port surface (face surface facing the recording material) of each of the recording heads 62A to 62D.

Further, inks of different colors are ejected from the ejection ports of each of the print heads 62A to 62D.
~62D are yellow, magenta, cyan, respectively.
It is configured to form black monochrome patterns and to record a predetermined color image by controlling the overprinting of these monochrome patterns.

Each of the recording heads 62A to 62D is, for example, an inkjet recording head that ejects ink using thermal energy, and is equipped with an electrothermal transducer for generating thermal energy. It is possible to perform recording by ejecting ink from each ejection port by the growth of bubbles due to film boiling caused by the thermal energy generated.

In FIG. 7, a carriage 63 on which the head unit 61 is mounted is movably supported along a guide rail 64, and is reciprocated by a carriage motor 66 via a timing belt 65.

This carriage motor 66 is a motor with an encoder, for example, a stepping motor with an encoder is used.

A sheet-like recording material 67 made of paper, a thin plastic plate, etc. is transported by a pair of conveyance rollers 69 driven by a conveyance motor (paper feed motor) 68 and a pair of holding rollers 7 that cooperate with the conveyance roller pair 69.
0, the paper is conveyed (paper fed) in the direction of arrow f along a predetermined path at a predetermined timing and a predetermined pitch.

This conveyance motor 68 is also a motor with an encoder, for example, a stepping motor with an encoder is used.

While the recording material 67 is held flat at a recording position facing the recording heads 62A to 62D, the carriage motor 66 is driven to perform recording while main scanning with the recording heads 62A to 62D. , when one line of recording is completed, the recording material 67 is pitch-fed in the direction of arrow f by driving the conveyance motor 68, and the next line is recorded.

Note that the carriage 63 has rads 62A to 62 for each recording.
Ink tanks 73A to 73D for supplying ink of the color corresponding to D are replaceably installed.

Each recording head 62A to 62D and each ink tank 73A to
73D are connected through an ink supply pipe 71 and an ink return pipe 72, respectively.

A home position H is set at a predetermined position within the movement range of the carriage 63 and outside the recording area, and a recovery device 74 is installed at the home position H for recovering ink failure from the recording rads 62A to 62D. is installed.

This recovery device 274 is attached so that it can be moved back and forth,
A cap 75 is provided on the front surface of each of the recording heads 62A to 62D to seal the ejection port surface (the surface on which the ejection ports are formed).

The recovery device 74 is disposed at a position where the recording heads 62A to 62D face each other when the carriage 63 comes to the home position H, and in addition to camping after recording (sealing the ejection port surface), the recovery device 74 It is used to receive ink that has been ejected incorrectly, and to perform a recovery operation such as pressurizing and circulating ink to the recording head to eliminate ink ejection failure.

A recovery motor (not shown) is used as a drive source for each operating section of the recovery device 74, and a motor with an encoder can also be used as the recovery motor.

Note that the carriage motor 66, the transport motor 68, and the recovery motor do not necessarily all have to be motors with encoders, and only the necessary ones can be constructed with motors with encoders.

Also, when using a motor other than the above, a motor with an encoder can be used as the motor.

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of an encoder-equipped motor for a recording apparatus, such as the carriage motor 66, transport motor 68, or recovery motor.

In FIG. 1, a bearing housing 11 is formed in the center of a drum-shaped motor case 10 with one end open, and a plate 12 is attached to the open end surface of the motor case 10.
is fixed by fixing means such as caulking 13, and another bearing housing 14 is formed at the motor shaft center of the plate 12.

The mounting plate 12 also serves as an end plate for sealing the open end surface of the motor case 10.

Bearing 1 press-fitted into each bearing housing 11.14
5.16, the motor shaft 17 is pivotally supported.

A rotor 18 is press-fitted and fixed to the motor shaft 17 in the motor case 10, and rotor magnets 19 magnetized to N and S poles are formed at a predetermined pitch in the circumferential direction on the outer periphery of the rotor 18. There is.

A yoke having pole teeth facing the rotor magnet 19 is disposed inside the motor, which is made up of a motor case 10 and a mounting plate 12.
A stack of excitation coils 20, 21 is arranged.

The yokes include a first outer yoke 22 fixed to the end face of the motor case 10, a first inner yoke 23 and a second inner yoke 24 joined back to back, and fixed to the inner surface of the plate 12. It is composed of a second outer yoke 25.

A first excitation coil 20 is installed inside the first inner and outer yokes 22.23 via a bobbin 26, and a second excitation coil 20 is installed inside the second inner and outer yokes 24.25 via a bobbin 27. A coil 21 is attached.

The bobbin 26.27 is made of an insulating material such as plastic, and parts 26A and 27A of the bobbin 26.27 protrude from the side surface of the motor case 10. Motor one terminal member 28
．． 29 (4 or 6 in total) are led out.

A rotational force extraction means such as a pulley is fixed to the output side protrusion of the motor shaft 17.

An encoder 31 for detecting the angle and speed of rotation of the motor is attached to the outside of the motor case 10 on the side opposite to the output side of the motor.

The encoder 31 includes a coded disk 32 (e.g., a disk encoded with a slit pattern, striped pattern, magnetic pattern, etc.) positioned and fixed on a portion of the motor shaft 17 that protrudes from the motor case 10, and a motor case. 10 (for example, a photointerrupter, a reflective photoelectric sensor, a magnetic sensor, etc., a sensor that detects passage of the coded pattern when the motor rotates) 33.

The sensor 33 is connected to the motor one terminal member 28.29.
The sensor terminal member (in the illustrated example, a total of four encoder terminal members for t source and signal) 34 of the sensor 33 is located on the same side as the motor terminal member 28.29. It protrudes in approximately the same direction.

Each of the terminal members protruding on substantially the same side in the circumferential direction of the motor, that is, a total of four or six motor terminal members 28, 29 and a total of four sensor terminal members 34, has a predetermined shape. The motor one terminal member 28, 29 and the sensor one terminal member 34, which are made of rigid conductive rod-shaped or plate-shaped metal, are all fixed to the same substrate 35, and are formed at their tip portions. All the terminals connected to the motor, that is, the motor terminals 28A and 29A and the sensor terminal 34A are provided on this common substrate 35.

On the motor shaft 17, a plastic bearing member 39 having a bearing surface 39A perpendicular to the axial center is press-fitted and fixed at a predetermined position in the axial direction, and a coded circle whose center hole is press-fitted into the motor shaft 17 is fixed. The plate 32 is pressed against the surface 39A of the receiving member 39 by a resilient presser ring 40 which is also press-fitted, and is positioned and fixed.

The retainer ring 40 includes a spring portion 40 that is inclined in a direction to prevent removal and whose tip end is press-fitted into the motor shaft 17.
A and a flat annular plane portion 40B for uniformly pressing the coded disk 32 against the receiving surface 3'9A.

That is, the coded disk 32 is press-fitted into the center hole formed in itself to ensure coaxiality with the motor shaft 17, and furthermore, the receiver of the member 39 has a spring property with the surface 39A. The perpendicularity to the motor shaft 17 and the axial position are accurately ensured by being pressed between the retainer ring 40 and the retainer ring 40 having a diameter.

On the other hand, the sensor 33 has positioning protrusions formed at two locations on its mating surface fitted into positioning holes formed at two locations on the end surface of the motor case IO, and the other two locations ( For example, at two locations on both sides), there is a female screw 37 tapped into the burring part of the motor case 10 and a screw 3 fastened to the female screw.
8, it is positioned and fixed.

Therefore, a dustproof cover 36 for covering the encoder 31 is removably attached to the outer peripheral surface of the motor case 10.

This dustproof cover 36 is for preventing dust such as paper dust and ink from adhering to the coded disc 32 and the sensor 33. It is made of plastic molding, for example, and uses its elasticity to prevent unevenness. It is detachably fixed to the motor case 10 by a stand means.

FIG. 2 is a front view of the motor case 10 viewed from the open end, FIG. 3 is a longitudinal cross-sectional view taken along the line ■-■ in FIG. 2, and FIG. 5 is a front view seen from the open end side of the
FIG.

2 to 5, the end face of the motor case 10 is formed with positioning holes 54 (two locations) into which the positioning protrusions (not shown) of the sensor 33 fit, and these Burring portions 55 (two locations) having the female screws 37 for attaching the sensor 33 are formed on both sides of the positioning hole 54 .

That is, the sensor 33 is positioned and fixed on the outer surface of the motor case 10 by being positioned using the positioning hole 54 and then fastened to the burring portion 55 with the screw 38 .

Reference numeral 56 in FIGS. 2 and 3 indicates bar rings (three locations) for caulking and fixing the first outer yoke 22 to the inner side of the end surface of the motor case 10, and reference numeral 57 indicates the motor one terminal member 28. A notch for protruding the .29 to the outside of the motor case 10 is shown.

Therefore, as shown in FIGS. 2 and 3, two notches 81 are provided on the circumference of the open end surface of the motor case 10 for removably fixing the dust cover 36.
is formed.

On the other hand, 2 points on the circumference near the open end surface of the dustproof cover 36
A protrusion 82 that can be secured to the notch 81 of the motor case 10 with a snap action is formed at the location.

FIG. 6 is a partially enlarged longitudinal sectional view showing the shape of the projection 82.

As shown in FIGS. 4 to 6, each protrusion 82 is formed as an inward protrusion that can be elastically deformed outward in the radial direction by forming notches 83 on both sides.

Further, the inner diameter portion 84 of the dustproof cover 36 that fits with the motor case 10 has a dimension that fits with the outer diameter of the motor case 10 with almost no clearance, and when it is attached as shown in FIG. The two protrusions 82 are fixed between the two notches 81 and the mounting plate 12, and the dustproof cover 36 is prevented from moving relative to the motor case 10 in both the axial and circumferential directions of the motor. Fixed.

It should be noted that while the dustproof cover 36 is being attached to the motor case 10, the protrusions 82 are elastically deformed in the radial direction, so that the protrusions 82 can be easily inserted into the predetermined position 1 where the protrusions 82 are locked. .

Further, when removing the dustproof cover 36, it can be easily removed by opening the protrusion 82 from the end surface side and pulling it out.

Note that in FIGS. 4 and 5, a space 85 inside the dustproof cover 36 indicates a portion where the encoder 31 is housed, and the motor terminal member 28, 29 and Encoder-terminal member 3
A notch 86 is formed to allow the portion 4 to protrude to the outside.

According to the embodiment described above, the encoder disk 32 and sensor 33 of the encoder 31 are attached to the outside of the motor case 10, and the dustproof cover 36 covering the encoder 31 is detachably attached to the motor case 10. Therefore, even when installed in a recording device, it is possible to effectively prevent foreign matter such as paper dust and ink mist generated in the recording device from adhering to the coding disk 32 and the sensor 33. It is possible to prevent errors and instability in position control of the recording head and recording material due to detection errors such as code skipping of the encoder 31 due to adhesion of foreign matter, and therefore, deterioration of image quality due to fluctuations in the recording position, etc. An image was obtained with a recording device capable of performing stable, high-definition recording over a long period of time without any problems.

Moreover, since the dustproof cover 36 was fixed to the outer periphery of the motor case 10 so as to be easily attachable and detachable, a motor with an encoder for a recording device having a simple structure and excellent handling properties was obtained.

In the above embodiments, the case where the encoder-equipped motor according to the present invention is applied to a stepping motor used in an inkjet recording device was explained as an example, but the encoder-equipped motor according to the present invention can be applied to a wire dot type, a thermal The present invention can be similarly applied to motors of other types of recording devices, such as type or laser beam type recording devices.

Regardless of the number of recording heads installed in the recording device, in addition to the serial scan method in which the recording heads are mounted on the carriage 63, a line head with a length that covers the paper width of the recording material 67 is used. The present invention can be similarly applied to other types of recording devices, such as line-type recording devices, and in these cases, the same effects as in the above-mentioned embodiments could be achieved.

Furthermore, the encoder-equipped motor according to the present invention can be similarly applied to other types of motors than stepping motors as long as they are motors for recording devices, and the same effects as those described above can be achieved. I was able to do that.

Furthermore, the present invention can be widely applied to any motor equipped with an encoder having a coded disk and a sensor, regardless of the type of encoder such as a light blocking method, a light reflection method, or a magnetic method, and the same effect can be achieved. It is possible to achieve the desired effect.

(Effects of the Invention) As is clear from the above description, according to the present invention, in a motor equipped with an encoder used in a recording device that forms an image on a recording material based on image information, Since the encoder is arranged and a dustproof cover covering the encoder is attached to the motor case, it is possible to prevent contamination by dust, ink droplets, etc., and maintain stable motor rotation with high precision. A motor with an encoder for a recording device is provided.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the encoder-equipped motor for a recording device according to the present invention, FIG. 2 is a front view of the motor case seen from the open end of the motor case in FIG. 2 is a longitudinal sectional view taken along line 1[r-1 in Figure 2, Figure 4 is a front view of the dust-proof cover in Figure 1 as seen from the open end, and Figure 5 is
The figure is a vertical cross-sectional view taken along the line V-■ in Figure 4, Figure 6 is a partially enlarged vertical cross-sectional view showing the shape of the protrusion for installing the dustproof cover in Figure 4, and Figure 7 is a vertical cross-sectional view of the main body. 1 is a schematic perspective view showing the configuration of main parts of a recording device having an encoder-equipped motor according to the invention. Below, symbols representing main components in the drawings are listed. 10-Motor case, 12--11 mounting plate, 17--motor shaft, 18--rotor, 20.21-1--exciting coil, 22-25-- −
・-Yoke, 28.29--Motor one terminal member,
31--11-11 encoder, 32--encoding disk (slint disk, etc.), 33...sensor (photo ink converter, etc.), 34---encoder one terminal member, 35 board, 36---dust-proof cover, 38
----------- Screw (sensor installation), 54 --
-----Positioning hole, 61 head unit, 62A~6
2 I)-----1 recording head, 63----carriage, 66---1--carriage motor (motor with encoder), 67-----recording material, 68
---1--Transport motor (motor with encoder), 7 L-----Recovery device, 81--Notch, 82-----m-Protrusion, 84------1. Inner diameter part for fitting the motor case, 85--Space for storing the encoder, 86----Notch.

Claims (2)

[Claims] (1) In a motor with an encoder used in a recording device that forms an image on a recording material based on image information, the encoder is disposed outside the motor case, and a dust-proof cover covering the encoder is installed in the motor case. A motor with an encoder for a recording device that is attached to the motor case. (2) The dustproof cover is a plastic molded product,
2. The encoder-equipped motor for a recording device according to claim 1, wherein the encoder-equipped motor is engaged with the motor case by utilizing its elasticity.