JPH0467269B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to pads of a sheet recorder that are provided on the sheet recorder body on the side opposite to the head with the sheet sandwiched therebetween, and that are arranged on both sides of the head that moves. More specifically, the present invention relates to a pad for a sheet recorder that forms an air film between the pad and the sheet.

BACKGROUND TECHNOLOGY AND PROBLEMS Conventionally, in sheet recorders, pads are provided on the sheet recorder body on the opposite side of the head to hold the sheet, and these pads are placed on both sides of the moving head, and the pads are used to forcibly deform the sheet. A tent shape (see Fig. 1) was created by giving the sheet a contact point with the head. If the pad is directly pressed onto the seat, the pad will rub against the seat and damage the seat, reducing the durability of the seat. Therefore, attach a cushioning material such as flocking or non-woven fabric to the pad surface (the surface of the pad that comes in contact with the seat). When this cushioning material touches the sheet, the sheet is deformed and a hit is obtained.

However, with this method, the flocked or nonwoven fabric is constantly being rubbed against the sheet, so if used for a long time, dirt may accumulate and the contact may become poor. In addition, it is difficult to obtain a uniform surface on the pad surface with flocked or nonwoven fabrics, and it is therefore extremely difficult for the head to consistently produce good contact on both the inner and outer circumferences of the sheet.

Purpose of the Invention The present invention was made in view of the above-mentioned circumstances, and its purpose is to prevent the sheet from being damaged even without using flocked or nonwoven fabric, and to maintain a stable head even when used for a long time. To provide a pad for a sheet recorder, which can obtain good contact, is relatively easy to make a uniform pad surface, and can always obtain good contact with the head both on the inner and outer peripheries of the seat.

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is provided on the sheet recorder body on the opposite side of the head with the sheet held between the sheets, and is arranged on both sides of the moving head. A pad surface having a curvature approximately in the circumferential direction of the sheet was formed on each contact surface with the sheet.

With the above configuration, an air film is formed between the pad and the sheet, so there is no need to use flocking or non-woven fabric to prevent the sheet from being damaged, and the sheet remains stable even after long periods of use. You will be able to get a hit with the head. Furthermore, since it is relatively easy to create a uniform pad surface, good head contact can always be obtained on both the inner and outer circumferences of the seat.

Embodiments Before entering into the description of embodiments of the present invention, the principle of the present invention will first be explained with reference to FIG.

Hold sheet 2 on the opposite side of head 1 and
Pads 3a, 3b having a curvature R in the substantially circumferential direction (direction of rotation) are arranged on both sides of the head 1 which moves in the radial direction of the seat 2. And Patsudo 3
A and 3b are pressed onto the sheet 2 to form a tent shape, and when the sheet 2 is rotated in the direction of the arrow a, the sheet 2 hits the pads 3a and 3b and the head 1 at a predetermined speed. However, since the sheet 2 has a speed, air is drawn in, and air pressure is generated between the pads 3a and 3b. According to the following general formula (1), the air film 4
a, 4b occur.

Δh=KR(μV/T) ⁿ ...(1) Here, Δh=air film thickness K=constant R=curvature of pad μ=viscosity coefficient of air V=sheet speed T=sheet tension n=constant .

From this general formula, seat 2 has pads 3a, 3b
(Actually, since the pads 3a and 3b are fixed, the sheet 2 will deform and move down slightly.) According to experiments, the curvature of the pad surfaces of pads 3a and 3b is
It has been confirmed that when the head force is 0.6 to 0.7 g (gram) at R30 (30 mm radius), air films 4a and 4b of 8 to 15 μm (micron) are formed. Since air films 4a and 4b are formed between the pads 3a and 3b and the seat 2 during rotation of the seat 2, the seat 2 is not damaged by the pads 3a and 3b and has a good head. You will get a hit.

Next, an embodiment of the present invention will be described with reference to FIGS. 1 to 3. Pads 3a and 3b each having a curvature of, for example, R30 in the substantially circumferential direction (direction of rotation) of the seat are protruded from a V-shaped aluminum base 5, and are integrally formed with the base 5. Molded. The ends of both pads 3a, 3b on the outer peripheral side relative to the seat 2 are connected by a connecting member 6 whose surface is in contact with both pad surfaces. Generally, the outer periphery of the sheet 2 has low rigidity and the sheet tension T due to centrifugal force is small, so the sheet 2 tends to flap and the air film is unstable. For this reason, if no recess is provided between the pads 3a and 3b and the outer periphery is made a continuous surface by the connecting member 6, the air film will be stabilized. Note that this continuous surface may be provided not only on the outer circumference but also on the inner circumference.

Next, on the V-shaped base 5, as shown in FIG.
Three female screw holes 8a, 8b, 8 at three point positions in a letter shape
c are provided, and these female screw holes 8a,
In the vicinity of 8b and 8c, through holes 9a, 9b, and 9c each having a counterbore surface are formed. Of these through holes, 9a is a circular hole;
b is a long hole in the circumferential direction of the sheet 2, and 9c is a long hole in the radial direction. Also pad 3a, 3
A penetrating long hole 10 is formed in the base 5 between b. This elongated hole 10 corresponds to the protrusion of the head 1, and the elongated hole does not have to be penetrating as long as it is a recess.

Next, the attachment of the pad to the main body of the sheet recorder will be explained with reference to FIG. Guide pins 13a, 13 are inserted into the through holes 9a, 9b, 9c of the base 5 at predetermined positions of the lid 12 so that their large heads are hidden within the counterbore surface.
b, 13c are fixed. A base 5 and a lid 1 are attached to each of these guide pins 13a to 13c.
A compression spring (not shown) is fitted between the pad 2 and the base 5, that is, the pad 3.
a and 3b are biased toward the seat 2 and are constructed so as not to vibrate while the seat 2 is rotating. Reference numerals 14a, 14b, and 14c denote pads 3 screwed into the female threads 8a, 8b, and 8c of the base 5, respectively.
These are the height and inclination adjustment screws a and 3b. When the lid 12 is closed and locked, the adjustment screw 1
The heads of 4a and 14b are not shown in the chassis 1.
The head of the adjusting screw 14c is adjusted so as to come into contact with the reference plane on the top surface of the rotary drive shaft 16 on the chassis 15, respectively, and the head of the adjusting screw 14c is fixed to the base 5 after adjustment. In this way, the pads 3a and 3b are adjusted at three points and are configured to always be held at a predetermined correct position relative to the head 1, thereby maintaining good contact with the head 1. . Note that the long holes 9b and 9c are used for this adjustment.

Next, the operation of the sheet recorder will be briefly explained. In FIG. 2, a seat 2 (not shown) is attached to the rotary drive shaft 16 in its entirety, and the seat 2 is rotationally driven by a drive motor provided on the lower surface of the chassis 15 via a belt 17. At this time, the adjustable head 1 attached to the rotating lever 18 is moved to the center of the seat 2 by rotating the lever 18 around the fulcrum pin 19 by a stepping motor also provided on the lower surface side of the chassis 15. That is, it moves toward the center of the rotary drive shaft 16. Note that the rotation lever 18 is always urged in the forward rotation direction by a tension spring 20, thereby absorbing the backlash of the gear. Further, the rotating lever 18 has gate-shaped members 21a, 2
Compression spring 22 interposed between 1b and lever 18
It moves while being pressed against the sliding surface by a and 22b.

4 and 5, second and third embodiments of pads according to the invention are shown. These embodiments differ from the first embodiment in that grooves are formed on the pad surfaces of pads 3a and 3b, and other points are the same as in the first embodiment. Therefore, an air film is formed between the pads 3a, 3b and the sheet 2, as in the first embodiment. In the second embodiment shown in FIG. 4, the grooves 24 are formed substantially in the circumferential direction of the sheet, and in the third embodiment shown in FIG.
5 is formed. By providing the grooves 24 and 25 on the pad surface in this way, the pad 3 can be
a, 3b are prevented from sticking to the sheet 2,
This makes it possible to obtain more stable head contact even when starting/stopping.

Although the pads 3a and 3b described above are molded integrally with the base 5, they may be molded separately and then integrally joined. In any case, pad 3
Since the pads a and 3b are molded, it is easy to form the pad surfaces into uniform surfaces. Therefore, it is easy for the head 1 to always obtain good contact with both the inner and outer circumferences of the seat 2. Further, the pads 3a and 3b do not necessarily need to be made of metal, and may be made of synthetic resin molded products, for example.

Next, a fourth embodiment of the present invention will be described with reference to FIGS. 6 and 7. The difference between this fourth embodiment and the first embodiment is that there are The point is that dust removal pads 27 and 28 are provided to sandwich the sheet 2. And this pad 27, 28
Since flocks 27a, 28a or non-woven fabric are attached to the tips of the pads, dirt that gets between the sheet 2 and the pads 3a, 3b is attached and absorbed. Therefore, since the intrusion of dirt is prevented, dirt does not enter between the sheet 2 and the pads 3a and 3b.
Damage to the sheet 2 by this dirt is avoided or greatly reduced. Therefore, the effectiveness of the air film type pad is further improved and it becomes easier to use. Furthermore, the dust removal pads 27 and 28 are
For example, the pad 28 is configured to be able to move freely within the through hole 29 of the base 5, so that it can be adjusted independently of the pads 3a and 3b.

Effects of the Invention As explained above, according to the present invention, a pad surface having a curvature approximately in the circumferential direction of the sheet is formed on the contact surface of the pad with the sheet, and an air film is formed between the pad and the sheet. , so there is no contact between the pad and the seat. Therefore, there is no need to use flocked or non-woven fabric as in the past, and there is no need to damage the sheet, and unlike conventional flocked or non-woven fabric, it is less susceptible to deterioration over time due to dirt, etc., so it can be used for long periods of time. Stable head contact can be obtained even when the sheet is pressed, and the durability of the sheet is further improved.

Further, according to the present invention, since flocking or nonwoven fabric is not used as in the conventional pad, it is easy to form a uniform pad surface, and it is possible to obtain good head contact on both the inner and outer peripheries.

[Brief explanation of drawings]

Figure 1 is an explanatory diagram of the principle of the present invention, and Figure 3 -
2 is a perspective view of the main parts of the sheet recorder with the lid open, FIG. 3 is a perspective view of the pad and base of the present invention, and FIGS. 4 and 5 are views of the present invention. A third example showing the second and third embodiments of the pads according to
6 and 7 are views showing the fourth embodiment of the present invention, and FIG. 6 is a perspective view similar to FIG. The figure is similar to FIG. 1. In addition, in the symbols used in the drawings, 1...Head, 2...Seat, 3a, 3b...Pad, 4
a, 4b...air film, 12...lid (sheet recorder main body), R...curvature in the circumferential direction.

Claims (1)

[Claims] 1. In the pads of the sheet recorder, which are installed on the sheet recorder body on the opposite side of the head with the sheet in between, and are arranged on both sides of the moving head,
A pad for a sheet recorder, characterized in that a pad surface having a curvature approximately in the circumferential direction of the sheet is formed on each contact surface of the pad with the sheet.