JPS6022769A - Pad of sheet recorder - Google Patents

Abstract

PURPOSE:To ensure a stable touch of a head even with a long period of use by forming a pad surface having a curvature approximately in the circumferential direction (revolving direction) of a sheet on the contact surface between a pad and the sheet and having different curvatures of the pad surface between a pad at the inlet side of the sheet and a pad at the outlet side of the sheet. CONSTITUTION:Pads 3a and 3b having a curvature R approximately in the circumferential direction of a sheet 2 are provided at both ends of a head 1 moving in the radius direction of the sheet 2 while holding the sheet between at the opposite side to the head 1. When the sheet 2 is revolved toward an arrow (a), air films 4a and 4b are formed between pads 3a and 3b and the sheet 2 during revolutions of the sheet 2. However a turbulent flow is produced with the pad 3b at the outlet side and therefore the thickness (h) of the film 4b is reduced. Thus the air film is not produced easily. In this connection, the curvature R2 of the pad 3b is set larger than the curvature R1 of the pad 3a in order to increase the thickness (h). As a result, the stable film 4b can be obtained even on the surface of the pad 3b.

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 across the sheet, and are arranged on both sides of the moving head. 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 by sandwiching the sheet, and these pads are placed on both sides of the moving head, and the pads forcefully deform the sheet. (See Figure 1A)
(manufactured by the company), which ensured that the seat and head were in contact with each other. 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 flocked or non-woven fabric to the pad surface (the surface of the pad that contacts the seat). When this cushioning material touched the sheet, the sheet was deformed, and the product was obtained. However, with this method, the flocked or non-woven fabric is constantly rubbed against the sheet, so if used for a long time, dirt will accumulate.
There are times when I am at fault.

Therefore, as will be explained later, a pad surface with a curvature in the circumferential direction (direction of rotation) of the sheet is formed on the contact surface of the pad with the sheet, and this creates a gap between the pad and the sheet. By forming an air film, it is possible to prevent the sheet from being damaged and to obtain stable contact of the head.

However, on the seat entrance side, the air is in a laminar flow and an air film is easily formed, but when it passes through the entrance side pad, the air is in a turbulent flow state, making it difficult to form an air film.

Therefore, if the above-mentioned curvature is made equal to that of the inlet and outlet pads, air film will be less likely to form on the outlet side.

Purpose of the Invention The present invention was made in view of the above-mentioned circumstances.The purpose of the present invention is to prevent the sheet from being damaged even without using flocked or non-woven fabric, and to maintain a stable head even when used for a long time. In order to obtain the desired contact, an air film is formed between the sheet and the air film, and this air film is easily formed on the outlet side pad surface in the same way as on the inlet side pad surface, so that the flow condition can be adjusted. To provide a pad for a sheet recorder that provides a stable air film despite changes.

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a sheet recorder pad that is provided on the sheet recorder body on the side opposite to the head with the sheet sandwiched therebetween, and is arranged on both sides of the moving head. A pad surface having a curvature approximately in the circumferential direction of the sheet is formed on each of the contact surfaces with the sheet, and the curvature of the pad surface is configured to be different between the pad on the entrance side and the pad on the exit side of the sheet. .

With the above structure, an air film is formed between the pad and the sheet, so there is no need to use flocking or non-woven fabric to damage the sheet, and it can be used for a long time. Also, stable contact between the seat and the head can be obtained. Moreover, the air film is not easily formed on the outlet side pad surface as well as on the inlet side pad surface, making it possible to always obtain a stable air film.

Embodiments Below, before going into the embodiments of the present invention, first of all, FIGS. 1A and 1B.
The principle of the present invention will be explained with reference to the drawings.

Sandwich the sheet (2) on the opposite side of the head (1) and place the sheet (
Pads (3a) (Sb) having a substantially circumferential direction (rotational direction) curvature R (symbol R is used in general terms) of 2)
are arranged on both sides of the head (1) which moves in the radial direction of the seat (2). And pad (3a) (+b)
When the sheet (2) is crimped onto the sheet (2) to create a tent shape and the sheet (2) is rotated in the direction of arrow a, the sheet (2) moves at a predetermined speed to the bats (3a) (+b) and the head (1).
corresponds to However, since the seat (2) has a speed, it draws in air, and air pressure is generated between it and the pads (3a) (-5b).
According to the theoretical formula (1) of the shear film (4a
) (4b) occurs.

h=KR(6μV/T)3...Song, song...Song (1)
Here, h = air film thickness = proportionality constant R = pad curvature μ = raw air viscosity coefficient ■ = raw air flow rate T = sheet tension.

From this theoretical formula, the seat (2) is the pad (3a) (3
It will float slightly away from b) (Actually, it will float)' Since (3a) and (5b) are fixed,
Seat - will be deformed and slightly lowered). According to experiments, when the curvature of the pad surface of the pad (3a) (3b) is about R30 (radius 60 mm) and the head force is 0.5 g (duram), an air film of several μ (microns) is released (4a) (
4b) has been confirmed to be possible. In this way, air films (4a) (4b) are formed between the pads (3a) (3b) and the seat (2) during the rotation of the seat (2), and the seat (2) is attached to the pad (3a). (3b)
As a result, there is no damage caused by K, and a good head contact can be obtained.

However, air is drawn in between the pads (3a) and (5b) and the seat (2), respectively, in a laminar flow state at the seat inlet side pad (3a) and in a turbulent flow state at the seat outlet side pad (3b). It will be done. That is, the proportionality constant l in the theoretical formula (1) differs between laminar flow and turbulent flow, and has a smaller value for turbulent flow. Therefore, the outlet pad (6b) is in a turbulent state.
), the thickness h of the air film (4b) becomes smaller,
The above-mentioned through-shear film becomes difficult to form. Therefore, the curvature R2 of the exit side pad (3b) surface is changed to the entrance side pad (3a).
By increasing the surface curvature R1 and increasing h, a stable air film (4b) can be obtained also on the exit side pad (3b) surface. In this embodiment, for example, the inlet side curvature R1 = 30, the outlet side pad 2 =
It is set to 40 mm.

Next, an embodiment of the present invention will be described with reference to FIGS. 1B to 3. Pads (with different curvatures in the substantially circumferential direction (rotation direction) of the seat, such as the curvature R1 of the entrance side pad (!l a) = 60 and the curvature R2 = 40 mm of the exit side pad (6b), respectively. 3a) (, 3b) are protruded from the figure 7-shaped aluminum base (5).
It is molded integrally with this base (5). A recess (7) corresponding to the protrusion of the head (1) is formed between the adjacent pads (+a) (3b).

Next, the ■-shaped base (5) K has three female screw holes (8a) (8b) (
8c) 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. Among these through holes, (9a) is a circular hole, but (9b) is a long hole in the circumferential direction of the sheet (2).
c) are each formed into a long hole in the radial direction.

Next, referring to FIG. 2, a description will be given of how the pad is attached to the main body of the sheet recorder. They are inserted into the through holes (9a) (9b) (9c) of the base (5) at predetermined positions on the lid so that their large heads are hidden within the seating surface. Guide bin (13a) (15b) (
13c) is fixed. Each of these guide pins (1+a) to (13c) has a base (5) and a lid (
A compression spring (not shown) is fitted between the base (5) or the pad (3a).
) (5b) is biased toward the seat (2) and is configured not to vibrate during rotation of the seat (2). Further, symbols (14a), (14b), and (14c) refer to the base (
These are height and inclination adjustment screws for the pads (5a) (+b) screwed into the female threads (8a, 8b, and 8C) of 5), respectively. And when the lid is closed and locked, the heads of the adjusting screws (14a) (14b) are on the reference plane on the chassis Q9, which is not shown, and the heads of the adjusting screws (14c) are on the rotating surface on the chassis Q9. They are each adjusted so as to come into contact with a reference surface which is the top surface of the drive shaft αe, and after adjustment, they are fixed to the base (5). In this way, the pads (3a) and (5b) are adjusted at three points and are configured to always be held at a predetermined and correct position with respect to the head (1) K, thereby improving the stability of the head (1). The current status is maintained. Note that the long holes (9b) and (9c) are the long holes used during skin adjustment.

Next, the operation of the sheet recorder will be briefly explained. Second
In the figure, the rotational drive shaft α6) JC seat (2) (
(not shown) is attached to the pack, and the seat (2) is driven by a bell) (not shown) from a drive motor installed on the bottom side of the chassis α9.
17]. At this time, the adjustable head (1) attached to the rotating lever α second is rotated by the lever α mark being rotated around the stepping motor fulcrum holder, which is also provided on the bottom side of the chassis α9. The seat (2) moves toward the center of the seat (2), that is, the center of the rotational drive shaft Qe. The rotation lever U is always urged in the forward rotation direction by a tension spring (A), thereby absorbing the backlash of the gear. In addition, the rotating lever θ has a compression spring (22a) interposed between the gate-shaped members (21a) (21b) and the lever αυ.
22b) and moves while being pressed against the sliding surface.

Next, FIG. 4 shows a second embodiment of the pad according to the present invention. The difference between this second embodiment and the first embodiment is as follows:
The outer peripheral ends of both pads (3a) and (3b) are connected by a connecting member (6) whose surfaces are in contact with both pad surfaces, and the curvature is different from that in the first embodiment. It's exactly the same. Therefore, it is clear that the same effects as in the first embodiment can be obtained in this second embodiment as well.

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.

Therefore, no recess is provided between the pads (3a) and (3b),
If the outer peripheral part is made into 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.

Note that the pads (5a) (5b) explained above are the base (5).
), but they may be molded separately and combined together. In any case, pad (3a)
Since (3b) is molded, it is easy to form the pad surface into a theoretical surface. Therefore, it is easy to achieve good contact between the head (1) and the seat (2) in accordance with theory. Further, the pads (5a) and (6b) do not necessarily have to be made of metal, and may be made of, for example, a synthetic resin molded product.

DETAILED DESCRIPTION OF THE INVENTION 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. Therefore, there is no contact between the pad and the sheet. 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 a long time. It is possible to obtain a stable and unheaded sheet even when the sheet is used, and the durability of the sheet is further improved.

Further, according to the present invention, since the curvature of the pad surface is configured to be different between the inlet side pad and the outlet side pad of the sheet, a stable air film is always obtained even on the outlet side pad where the flow condition is poor. Therefore, more stable head positioning can be obtained.

[Brief explanation of drawings]

1A and 1B are diagrams explaining the principle of the present invention.
The figure shows a case where the curvature of both pads is the same, FIG. 1B is a sectional view taken along the line I-I of FIG. 6 showing a case where the curvature according to the present invention is different, and FIG. 3 is a perspective view of the pad of the present invention and its base, and FIG. 4 is a perspective view similar to FIG. 6 showing a second embodiment of the pad according to IJIIK of the present invention. In addition, in the symbols used in the drawings, (1)...Head f2>...
......Sheet (3aX3b)...Pad (4aX4b)...Air film base......Lid (sheet recorder body) (R1) ~ (R2 ) is the circumferential curvature. Agent Masaru Ueya Yoshio Tsuneko Shunko Sugiura Figure 1A Figure 1B

Claims (1)

[Claims] In the pad of the sheet recorder, which is provided on the sheet recorder body on the side opposite to the head with the sheet sandwiched between them, and which is arranged on both sides of the moving head, each of the contact surfaces of the pad with the sheet has approximately the same amount as the sheet. A pad for a seat recorder, characterized in that a pad surface is formed with a curvature in the circumferential direction, and the curvature of this pad surface is configured to be different between an entrance side pad and an exit side pad of the seat.