JPS6347628B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a liquid jet (inkjet) recording device, particularly an on-demand type liquid jet recording device.

In liquid jet recording devices, recording is generally performed by reciprocating the recording head, and some of these devices have a liquid reservoir that reciprocates integrally with the recording head.

This type of device connects a liquid reservoir that is fixed to the main body of the device and accommodates the main volume of liquid (ink) with the movable liquid reservoir through a feeding pipe to replenish the liquid, and is lightweight for reciprocation. This avoids frequent replacement of the movable liquid reservoir due to the small liquid storage volume for the sake of efficiency.

In such a device, the smooth and stable supply of liquid (ink) to the recording head during the recording operation of the recording head depends on the liquid ejected from the orifice provided at the tip of the recording head. This is an essential requirement in order to stably reproduce the flight of liquid particles in the form of droplets, which is an essential requirement for obtaining high quality recorded images. A weak point remains.

Furthermore, in devices in which the recording head reciprocates at high speed, such reciprocating motion has a great effect on the supply of liquid from the liquid reservoir to the recording head, causing instability in the amount of liquid supplied and For example, supply disruptions occurred. In addition, in a device in such a system, a so-called sealed system in which the liquid path from the liquid reservoir to the tip of the recording head is closed to the outside air except for an orifice provided at the tip. Although it is necessary to realize a smooth and quick liquid supply operation that follows the liquid ejection operation of the recording head during recording, conventional devices still have unresolved problems in this respect.

[Objective] An object of the present invention is to solve the conventional problems and provide a liquid jet recording device that can perform good printing.

In other words, when introducing ink into the recording head or recovering printing from the recording head, it prevents air from entering the liquid path of the recording head, provides a stable supply of ink, protects the recording head, and ensures reliable printing. This means that recovery can be performed with extremely simple operations.

Another object of the present invention is to simplify, reduce the size and cost of a liquid jet recording apparatus.

A liquid jet recording apparatus according to the present invention includes a recording head having an orifice for discharging liquid, a first liquid reservoir containing liquid, and a second liquid reservoir communicating with the recording head and storing liquid to be supplied to the recording head. A liquid reservoir;
a feeding pipe connecting the first liquid reservoir and the second liquid reservoir, a cap covering the orifice, and a moving means for moving the cap in a predetermined direction;
as a liquid introducing means, means for introducing the liquid into the second liquid reservoir by suctioning through a first connecting pipe connected to the second liquid reservoir, and a second liquid introducing means connected to the cap. This object can be achieved by comprising means for introducing liquid into the recording head by suction through a connecting tube.

[Effect] According to the present invention, by suctioning from the second liquid reservoir and the recording head, the second liquid reservoir is drawn from the first liquid reservoir.
The ink can be introduced into the reservoir and then into the recording head.

Therefore, even if the amount of ink in the second liquid reservoir that communicates with the recording head is less than the predetermined amount, it is possible to introduce a predetermined amount or more of ink into the second liquid reservoir and then release the ink inside the recording head. By introducing ink into the recording head, it is possible to prevent air from entering the recording head and causing printing failure. It is also possible to easily cap the recording head to prevent clogging.

Furthermore, the meniscus recedes at the recording head,
Even if ink cannot be ejected due to air bubbles or clogging, the ink can be reliably supplied by suction to release the ink ejecting inability and introduce ink into the second reservoir and recording head. Can perform recovery actions.

[Example] The present invention will be explained below with reference to the drawings.

FIG. 1a is a schematic perspective view for explaining one example of a preferred embodiment of the liquid jet recording device of the present invention, and FIG. 1b is a schematic perspective view for explaining the structure of the main part thereof. It is a schematic cross-sectional view.

The liquid jet recording apparatus shown in FIG. 1 includes a first liquid reservoir 101 containing a main volume of liquid called ink required for recording, and a first liquid reservoir 101 that communicates with the first liquid reservoir 101 through a feed pipe 102. Second liquid reservoir 1
03. A liquid jet recording head 1 configured to be able to reciprocate integrally with the second liquid reservoir 103.
04, a liquid introducing means 106 connected to the second liquid reservoir 103 through a first connecting pipe 105; and a liquid introducing means 106 connected to the second liquid reservoir 103 through a second connecting pipe 139; A liquid receiving means 107 is provided for engaging the tip of the cover and receiving liquid flowing out from the recording head 104. The recording head 104 has a carriage 109 that is fixed inside a head holder 108 and reciprocates in the direction of a double-headed arrow A to protect the leading end of the recording head 104 from mechanical damage.
It is installed in.

The second liquid reservoir 103 is located at the rear of the head 104 in communication with the internal liquid path of the recording head 104, is integrally constructed with the head holder 108, and is integrally formed with the recording head 104 in the direction of the double-headed arrow A. It moves back and forth along the .

The portions of the feeding pipe 102 and the first connecting pipe 105 connected to the second liquid reservoir 103 are connected to the second liquid reservoir 103.
03 is disposed along the reciprocating direction (the direction of the double-headed arrow A), and reciprocates in the direction of the arrow A in conjunction with the reciprocating movement of the second reservoir 103. Feed pipe 102 and the first
As shown in the figure, the position where the connecting pipe 105 is connected to the second liquid reservoir 103 is such that the second liquid reservoir 103 is connected to the second liquid reservoir 103 more efficiently during recording. The communication hole that communicates the liquid reservoirs 103 faces in the moving direction of the liquid reservoirs 103.

In case of blockage, the movable parts 110 and 111 of the feed pipe 102 and the first connecting pipe 105 remain connected to the second liquid reservoir 103 while remaining in the state along the arrow A.

However, even when the feeding pipe 102 is connected to the second liquid reservoir 103 from a direction perpendicular to arrow A or a direction close to it, the connecting portion 112 of the feeding pipe 102 to the second liquid reservoir 103 is connected to the feeding pipe 102. If the length of the movable part 110 is sufficiently short compared to the length of the movable part 110 of The second liquid reservoir 103 is connected to the second liquid reservoir 103.
If the movable portion 110 of the feed pipe 102 is arranged so as to be bent at a right angle at a position very close to The movable part 11 of the feed pipe 102
Due to the reciprocating motion of 0, the liquid is efficiently fed from the first liquid reservoir 101 to the second liquid reservoir 103 through the feeding pipe 102.

The efficiency of liquid feeding due to such reciprocating motion of the movable portion 110 of the feed pipe 102 increases as the reciprocating motion of the movable portion 110 becomes faster. Therefore, even when performing high-speed recording by increasing the frequency of droplet formation on the recording head 104 and increasing the speed of the reciprocating motion of the recording head 104, the movable portion 110 does not move the recording head 10.
4, the second liquid reservoir 103 is replenished with liquid corresponding to the amount of liquid used according to the amount of liquid used. The liquid is replenished in just the right amount, and no instability or inability to eject the liquid from the recording head 104 occurs.

Furthermore, the efficiency of supplying liquid to the second liquid reservoir 103 due to the reciprocating motion of the movable portion 110 is
The reciprocating movement of the second liquid reservoir 103, which reciprocates integrally with the recording head 104, tends to increase or decrease depending on the degree of acceleration or deceleration in the reciprocating movement of the recording head 104. If you synchronize with
An amount of liquid commensurate with the amount of liquid used is replenished to the second liquid reservoir 103 in accordance with the scanning speed of the recording head 104.

Therefore, since the liquid is efficiently replenished according to each recording scanning speed from low to high speed, high quality recording prints can be obtained even in the case of low speed recording or high speed recording. . In addition, since the liquid is replenished to the second liquid reservoir 103 in just the right amount according to the scanning speed of the recording head 104, even if the scanning speed of the recording head 104 fluctuates, there is no problem in replenishing the liquid. It will not cause any trouble.

The second liquid reservoir 1 due to the reciprocating movement of the second liquid reservoir 103
The efficiency of supplying liquid to 03 increases to some extent as the slope of acceleration or deceleration during forward or backward movement of the second liquid reservoir 103 increases to a certain extent. One example of this is to increase the direction change speed from forward movement to backward movement and from backward movement to forward movement, as long as the direction change speed in the reciprocating movement of the second liquid reservoir 103 is rapid. Second liquid reservoir 1
In principle, the efficiency of liquid supply to 03 can be increased.

In the case of the apparatus shown in FIG. 1a, the second reservoir 103 and the recording head 104 are mounted on the same carriage 109;
9 reciprocates on the sliding shaft 113, but in order to weaken the collision impact at both ends of the sliding shaft 113, the carriage 109 is attached to the sliding shaft fixing members 114-1, 114.
damper 115-1 made of a cushioning material such as sponge or rubber, at a predetermined position of each of
115-2 is provided.

The damper 115 has the function of providing a buffering effect when the carriage 109 collides with the damper 115;
It also serves to improve the efficiency of liquid supply through the feed pipe 102 to the liquid reservoir 103.

The carriage 109 can change its direction of movement even in the middle of the sliding shaft 113 using a drive mechanism, which will be described later, without traveling to the position of the damper 115.

The feed pipe 102 and the first connecting pipe 105 are bent into a U-shape and are fixed to the main body of the apparatus by a fixing plate 116 at approximately the center of the maximum width of movement of the carriage 109. Therefore, the feeding pipe 102 and the first connecting pipe 105 have the fixed plate 116 as a fulcrum, and the movable parts 110 and 111 located upstream of the fixed plate 116 each move to the second liquid reservoir 1.
Along with the reciprocating movement of 03, it repeatedly makes reciprocating movements along the direction of the double-headed arrow A while making turns.

The movable portion 110 of the feed pipe 102 and the movable portion 111 of the first connecting pipe 105 are connected to the second liquid reservoir 103.
At the side, it is attached to a carriage 109, and by virtue of this attachment to the carriage 109 and support on a fixed plate 116, the movable parts 110 and 111 are arranged along a sliding axis 113.

Next, the main parts of the apparatus shown in FIG. 1a will be explained with reference to FIG. 1b.

In FIG. 1b, in order to avoid complication of explanation, detailed illustration of the first liquid reservoir 101 is omitted, and
The first feed pipe 102 and the first connecting pipe 105 are shown only to show the coupling relationship with each part, and are not shown in their actual arrangement state (the state shown in FIG. 1a).

The recording head 104 is held in a head holder 108 and attached to a carriage 109. The recording head 104 includes a cylindrical member 118 made of glass or the like and having an orifice 117 for ejecting liquid at its tip, and a cylindrical piezoelectric element 119 fixed to the outer periphery of the cylindrical member 118. The piezoelectric element 119 is driven by applying a pulse voltage to the piezoelectric element 119 through a lead electrode (not shown).

The recording head 10 is located at the rear end of the recording head 104.
A supply pipe 120 is connected to communicate the liquid path in the recording head 104 with the second liquid reservoir 103, and to supply the liquid in the second liquid reservoir 103 to the recording head 104. The rear end of the supply pipe 120 inserted into the second liquid reservoir 103 from the upper part of the second liquid reservoir 103 extends to the bottom of the second liquid reservoir 103, and is provided at its terminal end. A filter 122 having a large number of fine liquid flow channels is attached to the liquid introduction port 121 by a filter attachment member 123. The filter 122 prevents foreign matter from entering the supply pipe 120 in order to prevent the liquid path in the supply pipe 120 and the recording head 104 from being clogged with foreign matter, such as solid dust. It works to prevent.

Separately, when the second liquid reservoir 103 fluctuates, the filter 122 detects that the vibrations generated in the liquid in the second liquid reservoir 103 affect the liquid filling the liquid path in the recording head 104, causing the liquid to change. It also acts as a vibration buffer to prevent unstable discharge. Furthermore, when the second liquid reservoir 103 is violently moved, gas mixed into the liquid flows into the supply pipe 120.
It also works to prevent it from creeping into the side.

The second liquid reservoir 103 has an internal volume that accommodates a predetermined amount of liquid, and includes a liquid storage member 124 having an opening at the top and a liquid storage member 124 for sealing.
It consists of a rubber sheet 125 and a tank cap 126 for sealing the opening of the recording head 10.
It is attached to the carriage 109 so as to move integrally with 4.

The tank cap 126 is securely attached to the liquid storage member 124 by, for example, a mounting screw or the like while pressing against a rubber sheet 125 in order to seal the inside of the second liquid reservoir 103. A feed pipe 1 is provided on the side surface of the liquid storage member 124 in the moving direction (the back side of the page in the figure).
02 and 2 connected to the first connecting pipe 105, respectively.
Two openings 127-1 and 127-2 are provided.

Opening 127- connected to first connecting pipe 105
1 approximately determines the maximum amount of liquid that can be accommodated in the second liquid reservoir 103. Therefore, when designing and manufacturing the second liquid reservoir 103, the opening position should be carefully selected. 127-1 is provided.

In the device having a sealed and movable liquid reservoir according to the present invention, the opening 127-1 is provided below the uppermost part of the side surface of the liquid storage member 124 by a predetermined distance, thereby allowing the second liquid to be stored. The upper surface of the liquid contained in the reservoir 103 is positioned at the liquid level shown by the dotted line in the figure, so that an air layer is formed above the liquid level. The formation of such an air layer in the second liquid reservoir 103 causes droplet ejection to become unstable due to the liquid surface vibration caused by the rapid direction change when the second liquid reservoir 103 reciprocates. prevent the impact to the maximum extent possible. or,
This air layer stably supplies the liquid into the second liquid reservoir 103 due to the negative pressure formed within the second liquid reservoir 103 when the liquid is ejected from the recording head 104. The volume of the air layer formed in the second liquid reservoir 103 is determined according to the maximum amount of liquid that can be accommodated in the liquid reservoir 103.

The opening 127-2 communicating with the feed pipe 102 may be provided above or below the opening 127-1. In order to prevent the liquid from flowing out as much as possible, below the opening 127-1,
Preferably, it is provided near the bottom of the second liquid reservoir 103.

A fluid resistance body 128 is provided in the middle of the first connecting pipe 105 that communicates between the second liquid reservoir 103 and the liquid introduction means 106 in order to adjust the liquid resistance of the first connecting pipe 105. . The fluid resistor 128 is made of, for example, a porous material having many fine through holes, felt, or a filter material such as a bundle of many fine glass fibers.

The fluid resistor 128 is configured such that when liquid is supplied into the second liquid reservoir 103 by operating the liquid introduction means 106, a required amount or more of liquid flows into the second liquid reservoir 103, and the opening 127- 1 to the liquid introduction means 106 side through the first connecting pipe 105, and by the method described later, the first It also functions to adjust the degree of suction sucked through the connecting pipe 105.

The first connecting pipe 105 is divided into two parts, an upstream part and a downstream part, at the position where the filter 128 is provided, and these two connecting pipe parts are connected by a mounting pipe 129 for attaching the filter. There is.

The downstream end of the first connecting pipe 105 is connected to an inlet 130 provided in the liquid introducing means 106 .

The liquid receiving means 107 has the function of covering the tip of the recording head 104 to prevent clogging caused by drying of the liquid at the tip, and the function of the liquid receiving means 107.
It has the function of performing printing recovery of the recording head 104 and the function of supplying liquid to the second liquid reservoir 103 in cooperation with 06.

The liquid receiving means 107 is composed of a cap 133 that covers the orifice 117 of the recording head 104 and receives the liquid flowing out from the orifice 117, and a cap moving means that moves the cap 133 in a predetermined direction. cap 133
is made of an elastic material such as rubber having holes. The means for moving the cap is a slide shaft 131.
and arrow B and arrow C along the slide shaft 131.
It is provided so that it can slide freely in both directions shown in
Cap holder 13 with cap 133 attached
2, and a capping knob 1 for sliding the cap holder 132 in the direction of arrow B.
34 is provided to surround the slide shaft 131 in order to slide the cap holder 132 in the direction of arrow C, and one end thereof is connected to a spring retainer 135.
a spring 136 fixedly attached to the spring 136, and a capping stand 137 to which these are integrally attached.
and has.

A liquid introducing means 106 is provided at the rear end of the cap 133.
A second connecting pipe 139 communicating with an inlet 138 provided in the inlet 138 is connected. cap 133
To cover the tip of the recording head 104, push the capping knob 134 in the direction of arrow D so that the capping holder 132 can cover the recording head 104.
This is done by being pushed out toward an orifice 117 provided at the tip of the. To cover the tip of the recording head 104 with the cap 133, the cap holder 132 is slid in the direction of arrow B, and the cap 133 is pressed against a member that holds the tip of the recording head 104, so that the cap 133 is in close contact with the member. Cap holder 132 C
The slide in the direction is the arrow F of the spring 136.
It is achieved by the restoring force in the direction.

The liquid introduction means 106 is a suction means (suction pump), and the operation of the suction mechanism brings the inside of the second liquid reservoir 103 into a reduced pressure state through the first connecting pipe 105. In this reduced pressure state, the liquid introducing means 10
By operating the suction mechanism 6, the first connecting pipe 1
05 through the second liquid reservoir 103 and the liquid introducing means 1
06 based on the pressure difference formed between the two. The degree of pressure reduction and the time for maintaining the reduced pressure state are set so that a predetermined amount of liquid is smoothly supplied from the first liquid reservoir 101 to the second liquid reservoir 103 through the feed pipe 102.

The supply pipe 120 provided at the rear end of the recording head 104 is connected to the recording head 1 as described above.
Cylindrical member 1 which is a means for forming a liquid path in 04
It may be connected to the cylindrical member 118, or it may be an extension of the upstream end of the cylindrical member 118.

The materials constituting the feed pipe 102, the first connecting pipe 105, the second connecting pipe 139, and the supply pipe 120 are materials that can smoothly supply the liquid and do not cause any unfavorable interaction with the liquid. If so, most of them can be used. Among these, tubes made of glass, plastic, etc. are particularly useful in the present invention, and examples of plastics include vinylidene chloride, vinylidene fluoride, polyester, polyvinyl chloride, polyethylene, etc. can be cited as suitable.

The suction mechanism of the liquid introduction means 106 has a suction pump structure, and includes a cylinder 140 and a piston 141, which are an outer frame for the suction pump. The piston 141 is provided with a through hole 142 and a valve 143 below the through hole 142.
Three O-rings 144 are provided between the inner wall surface of the piston 141 and the three O-rings 144 are fitted into respective grooves provided around the outer circumference of the piston 141 so as to tighten the piston 141. During normal operation, the piston 141 is pushed up to the upper part of the cylinder 140 by a spring 145, one end of which is fixed to the bottom of the cylinder 140, as necessary. At the bottom of the cylinder 140 is an outlet 14 through which the liquid sucked into the liquid introducing means 106 flows out.
6 is provided.

As shown in FIG. 1c, the outlet 146, which is shown in a simplified manner in FIG.
are connected and provided.

Such liquid absorbing means 147 can be constructed using a so-called sponge, a porous material, felt, or the like. Alternatively, an outflow reservoir may be provided downstream of the outflow port 146 to accommodate the outflow liquid, and the outflow liquid may be accommodated in the outflow reservoir.

The liquid is supplied from the first liquid reservoir 101 into the second liquid reservoir 103 by lowering the piston 141 (as indicated by arrow G) by manually pressing the upper end of the piston 141 constituting the liquid introducing means 106. direction)
It is done through action. When the piston 141 descends, the valve 143 closes the through hole 142,
A space region 148 above the piston 141 of the cylinder 140 is made to have a negative pressure. This negative pressure state inside the cylinder 140 is transferred to the second cylinder via the first connecting pipe 105.
The pressure inside the liquid reservoir 103 is reduced, and a pressure difference is created between it and the first liquid reservoir 101 via the feed pipe 102. This pressure difference is caused by the pressure difference between the first liquid reservoir 101 and the second liquid reservoir 101.
Transfer the liquid to 03. Piston 141
When the lowered position of the O-ring 144-1 is below the inlet 130, the capping knob 134 is pressed and the cap holder 13 is lowered.
2 in the direction of arrow B, the tip of the recording head 104 and the cap 133 are fitted in advance, that is, the recording head 104 and the liquid receiving means 107 are fitted together.
Based on the pressure difference formed through the liquid path inside each of the liquid receiving means 107, the second connecting pipe 139, and the recording head 104 when the
The liquid in the liquid reservoir 103 is sucked into the recording head 104, and the liquid is introduced and supplied to the liquid path inside the recording head 104. The movement of the liquid in the liquid path inside the recording head 104 via the liquid path of the liquid receiving means 107 and the second connecting pipe 139 is such that the amount of liquid introduced into the second liquid reservoir 103 is at least as large as the supply pipe 120. This occurs when the liquid inlet 121 at the tip of the liquid becomes immersed in the supplied liquid. Furthermore, when the liquid is supplied to the recording head 104, the amount of liquid flowing in from the liquid inlet 121 per unit time is such that the liquid level of the liquid supplied in the second liquid reservoir 103 is near the liquid inlet 121. In this case, the fluid resistance of the supply pipe 102 and the fluid resistance of the supply pipe 120 are set so that the flow rate of liquid from the first liquid reservoir 101 to the second liquid reservoir 103 is smaller than the amount of liquid flowing per unit time. be adjusted.

In order to better prevent gas or bubbles from entering the liquid path inside the recording head 104, the supply of liquid into the recording head 104 is stopped after a sufficient amount of liquid has been supplied into the second liquid reservoir 103. It is necessary to do so. This can be solved by making the downward movement of the piston 141 a two-stage motion. That is, in the first motion, the position of the O-ring 144-1 is between the inlet 130 and the inlet 1.
38, the piston 141 is lowered so that the second liquid reservoir 103 is depressurized only through the first connecting pipe 105, and by creating this depressurized state, the first liquid reservoir 101 introduces and supplies liquid to the second liquid reservoir 103. The degree of reduced pressure in the second liquid reservoir 103 created by this operation is greater than or equal to the level at which a sufficient amount of liquid is supplied into the second liquid reservoir 103. After a sufficient amount of liquid is supplied into the second liquid reservoir 103, as a second motion of the downward movement of the piston 141, the piston 141 is moved until the position of the O-ring 144-1 is below the inlet port 138. The liquid is lowered to form a pressure difference between the second liquid reservoir 103 and the liquid receiving means 107 through the recording head 104, and the liquid is introduced into the liquid path inside the recording head 104 to fill it. At this time, the speed of the downward movement of the piston 141 and the time interval when moving from the first motion to the second motion are such that the supply of liquid to the second liquid reservoir 103 and the supply of liquid to the recording head 104 are controlled. This is determined by appropriately considering the design of the device so that it can be carried out smoothly as desired.
In addition, the feed pipe 102, the first connecting pipe 105, the supply pipe 120, the opening 127-2 for liquid supply, and the opening 12
7-1 and the liquid inlet 121 as desired, and the inlet 130 and the inlet 1.
By appropriately designing the dimensions of 38 in relation to these, and manufacturing these, the downward motion of the piston 141 is not made into a two-step motion as described above, but a continuous downward motion is achieved. You can also make it look like this. Due to the downward movement of the piston 141,
When the liquid level of the liquid supplied in the second liquid reservoir 103 reaches an area above the opening 127-1, the cylinder 1
Liquid flows into headspace region 148 within 40 .
The liquid that has flowed into the spatial region 148 flows through the through hole 14
2 also flows into the opening of the valve 143 (piston 14
1 is pushed up in the direction of arrow H) and flows into the space region 149 in the lower part of the cylinder 140. When the downward movement of the piston 141 reaches the bottom dead center, the piston 141 is moved by the spring spring 136.
It rises in the direction of the home position (in the direction of arrow H) due to the repulsive force of . When the piston 141 rises, the through hole 1
Based on the pressure difference between 42 and the spatial region 148, the valve 143 is opened, and the upper spatial region 148 of the cylinder 140 is communicated with the atmosphere through the outlet 146. When the valve 143 is opened, the liquid present in the through hole 142 and the spatial region 148 flows into the cylinder 14.
0 into the lower space region 149. Figure 1b
The piston 141 of the liquid introduction means 106 in the device shown in FIG.
4-1, 144-2, and 144-3 are attached, and when the piston 141 is at the normal position (top dead center), the inlets 130 and 138 are closed by the piston 141 and these O-rings. . Printing recovery when the meniscus at the tip of the recording head recedes due to clogging inside the recording head 104 or loss of balance due to a drop in the liquid level in the second liquid reservoir 103, which hinders printing. The operation can be performed extremely easily using the same operating procedure as described above. This printing recovery operation will be briefly described below.

The first problem with printing is that the amount of liquid in the second liquid reservoir 103 decreases for some reason, and the recording head 104 decreases due to the drop in the liquid level in the second liquid reservoir 103. An example of this is that the meniscus from the vicinity of the orifice 117 position is too far back. Second, when printing is performed while reciprocating the second liquid reservoir 103 together with the recording head 104, the meniscus retreats too much due to an abnormal impact upon return, and the liquid does not return to its normal position. This is a case where droplet ejection becomes unstable, and furthermore, droplet ejection becomes impossible. Thirdly, the recording head 10, which is likely to occur during reciprocating movement of the second liquid reservoir 103,
This is the mixture of air bubbles into 4. The fourth problem is clogging due to drying of the liquid in the liquid path inside the recording head 104 or clogging due to the mixing of foreign matter.

If a problem occurs in printing due to the above-mentioned causes, printing can be recovered in the following manner. By pressing the capping knob 134, the cap 133 is moved and connected to the tip of the recording head 104, and when the piston 141 is pressed in the direction of arrow G, the O-ring 144-1 is removed in the first step.
passes through the inlet 130 and with it the upper space region 148 of the cylinder 140 connects to the first connecting pipe 10
5, the air in the second reservoir 103 is sucked by the negative pressure in the cylinder 140, and as a result, the liquid from the first reservoir 101 is transferred to the second reservoir 103. 103 by suction. At this time, the inlet 138 is connected to the O-rings 144-1, 144-2.
Since the recording head 104 is blocked by the recording head 104, no movement of liquid occurs through the recording head 104.

When the piston 141 further descends, in a second step, the O-ring 144-1 passes through the inlet 138, the inlet 138 communicates with the inside of the cylinder 140, and liquid is sucked through the recording head 104 and the liquid receiving means 107. At this time, if there is a substance causing discharge blockage along with the liquid, that substance is also sucked in and discharged into the upper space region 148 of the cylinder 140, and when the piston 141 rises, the valve 143 is opened. Lower space area 14 by opening
9, and is then discharged to the outside of the liquid introducing means 106 through the outlet 146 and absorbed into the liquid absorbing means 148.

As described above, when the piston 141 constituting the liquid introduction means 106 is pressed in the direction of the arrow G,
First, the residual air in the second reservoir 103 is sucked out, and as a result, the liquid is injected from the first reservoir 101 into the second reservoir 103, and the rear end of the supply pipe 120 is filled with liquid. After being immersed, the liquid is sucked through the recording head 104, thereby preventing air from entering the liquid path inside the recording head 104. Furthermore, by repeating the pressing operation of the piston 141 as necessary, the liquid level in the second liquid reservoir 103 rises and reaches the opening 127-1, but when this happens, the liquid is also sucked through the opening 127-1. The liquid level in the second liquid reservoir 103 is maintained at the height of the opening 127-1 (the position indicated by the dotted line). In this case, opening 127
There is a certain air layer in the second liquid reservoir 103 above -1, and as mentioned earlier, this air layer functions to absorb shock pressure when the second liquid reservoir 103 moves. be effective.

The liquid absorption means 147 is connected to the liquid introduction means 106 by a discharge pipe 150 as shown in FIG. Contains liquid that is drained through. The liquid absorbing means 147 shown in the figure includes a hard case and the case 1.
51 is comprised of a liquid absorber 152 that has a large storage capacity for liquid, such as glass wool, felt, or a porous material, and that absorbs liquid well. An opening 153 communicating with the atmosphere is provided on the upper surface of the hard case 151 so that the liquid absorbed by the liquid absorber 152 evaporates naturally.

Next, an outline of the operating mechanism of the apparatus shown in FIG. 1a will be described.

The reciprocating drive of the carriage 109 on which the recording head 104 and the second liquid reservoir 103 are mounted is controlled by a linear motor. The linear motor constitutes a closed magnetic circuit with a permanent magnet 154, a sliding shaft fixing member 114 that serves as a magnetic yoke plate, and a magnetic sliding shaft 113. Form a magnetic field. Coil bobbin 1 integrated with carriage 109
The carriage 109 is slidably disposed on the magnetic sliding shaft 113 such that a portion of the coil (not visible in FIG. 1) wound around the magnetic field 55 crosses the aforementioned magnetic field at right angles. When the coil wound around the coil bobbin 155 is energized, the carriage 109 reciprocates on the sliding shaft 113 with the driving force generated by Fleming's right-hand rule. The reciprocating motion of the carriage 109 on the sliding shaft 113 is caused by the coil bobbin 15
This is done by taking advantage of the fact that by changing the direction of the current flowing through the coil wound around the coil 5, the direction of the driving force also changes.

An electrical connection plate 156 is fixed to the carriage 109, and coil terminals 157-1, 157
-2, terminals 157-3, 157 of piezoelectric element 119
-4, a terminal 157-5 of a light emitting diode (not shown) and a terminal 157-6 of a phototransistor (not shown) for detecting the position of the carriage 109 are attached to the upper surface of the connection plate 156, respectively.
Additionally, these terminals 157 are connected to a flexible cable 158 fixed to one end of the connection plate 156.
are connected to each other. flexible cable 1
The other end of the cable 158 is folded back in the middle of the cable, and the cable 158 is fixed to the main body of the apparatus by the fixing plate 116. The end of the folded cable 158 is connected to a connector 159, and the carriage 109 is driven and the piezoelectric element 119 of the recording head 104 is controlled via the flexible cable 158.

Numeral 160 is an optical slit for detecting the printing position, and a large number of slits 161 are formed at equal intervals. The optical slit 160 is arranged in a space where a light emitting diode and a phototransistor as a pair of timing pulse generating elements arranged in the carriage 109 face each other.

Recording paper 16 printed by recording head 104
2 (indicated by a two-dot chain line) is inserted into the insertion groove 163 as shown by the arrow X, and is ejected from the ejection groove 164 in the direction shown by the arrow Y by the rotational movement of the paper feed roller 165.

The paper feed roller 165 sequentially feeds the paper 162 in the direction (direction indicated by arrow Y) by rotation of a gear 166 that transmits the rotational force of a pulse drive motor (not shown) in synchronization with the printing timing of the recording head 104.
Rotate to.

The form of the recording head in the present invention is not particularly limited to the form shown in FIG.
Recording heads using piezoelectric elements as described in publications such as USP3946398 and USP3747120, recording heads that utilize thermal energy as described in German Publication No. 2843064, and further recording heads described in these publications. Examples of the present invention include modified examples of the recording head, and other forms of the recording head applied to a liquid jet recording apparatus using a so-called continuous droplet formation method that controls the direction of flight of flying droplets.

FIGS. 2a and 2b show an example of a recording head which is similar in form to the recording head described in DE 2843064, but which has been modified into a shape suitable for mounting in the apparatus of the present invention.

The recording head 201 shown in the figure includes a heating element 2 that is a means for generating heat as liquid ejection energy.
02, eight selection electrodes 203 for applying voltage to drive each heating element, a heating element substrate 205 provided with a common electrode 204 commonly connected to each heating element, and each heating element. Liquid is supplied to eight grooves 206 provided to match the grooves in which the body is provided, and eight liquid paths 207 formed by these grooves and the side wall surface of the heating element 202 of the substrate 205. A grooved plate 209 is provided with a concave portion for forming a common liquid chamber 208.

At the rear of the common liquid chamber 208, there is a feed pipe 210 for supplying the liquid fed from the first liquid reservoir;
A first connecting pipe 211 is provided to connect with the liquid introduction means.

The function of the common liquid chamber 208 is similar to that of the second liquid reservoir explained in FIG. 1, but if the internal volume of the common liquid chamber 208 is small, It is desirable to provide an intermediate liquid reservoir between the common liquid chamber 208 and the recording head 201, which moves integrally with the recording head 201. If the air layer formed above the common liquid chamber 208 sufficiently plays the role of buffering the vibration of the liquid level in the common liquid chamber 208 due to the reciprocating motion of the recording head 201, the intermediate liquid reservoir has a similar effect. It is not necessary to provide a space in which an active air layer is formed.

[Brief explanation of the drawing]

Figures 1a, b, and c are diagrams illustrating one of the preferred embodiments of the present invention, with Figure 1a being a schematic perspective view and Figure 1b showing the main points of the present invention. A schematic cross-sectional view for explaining the main parts of the device according to the present invention, FIG. 1c is a schematic rear view schematically showing the back side of the device in FIG. 1a, and FIGS. FIG. 2A is a schematic perspective view, and FIG. 2B is a schematic plan view of a heating element base 205 constituting the recording head 201. 101...First liquid reservoir, 102...Feeding pipe, 1
03...Second liquid reservoir, 104...Recording head, 1
05...First connecting pipe, 106...Liquid introducing means, 107...Liquid receiving means, 108...Head holder, 109...Carriage, 110...First
Movable part of the feeding pipe, 111... Movable part of the first connecting pipe, 112... Connecting part of the feeding pipe, 113
...Sliding shaft, 114 ...Sliding shaft fixing member, 115
... Damper, 116 ... Fixed plate, 117
... Orifice, 118 ... Cylindrical member, 119 ...
... Piezoelectric element, 120 ... Supply pipe, 121 ... Liquid inlet, 122 ... Filter, 123 ... Filter mounting member, 124 ... Liquid storage member, 125 ...
...Rubber sheet, 126...Tank cap, 12
7...Opening, 128...Fluid resistance element, 129...
Mounting pipe, 130... Inlet, 131... Slide shaft, 132... Cap holder, 133... Cap, 134... Capping knob, 135...
... Spring presser, 136 ... Spring, 13
7...Capping stand, 138...Inflow port, 13
9...Second connecting pipe, 140...Cylinder, 14
1...Piston, 142...Through hole, 143...
Valve, 144... O-ring, 145... Spring, 146... Outlet, 147... Liquid absorption means, 148... Space region, 149... Space region,
150...Exhaust pipe, 151...Hard case, 1
52...Liquid absorber, 153...Opening, 154...
Permanent magnet, 155... Coil bobbin, 156...
Electrical connection board, 157...terminal, 158...flexible cable, 159...connector, 160...
...Optical slit, 161...Slit, 162...
... Recording paper, 163 ... Insertion groove, 164 ... Ejection groove, 165 ... Paper feed roller, 166 ... Gear.

Claims (1)

[Scope of Claims] 1. A recording head having an orifice for discharging a liquid, a first liquid reservoir containing the liquid, and a second liquid reservoir communicating with the recording head and storing a liquid to be supplied to the recording head. a feeding pipe connecting the first liquid reservoir and the second liquid reservoir; a cap that covers the orifice; and a moving means for moving the cap in a predetermined direction, and introducing the liquid. Means for introducing the liquid into the second reservoir by suction through a first connecting pipe connected to the second reservoir; and sucking through a second connecting pipe connected to the cap. A liquid jet recording apparatus comprising: means for introducing liquid into the recording head. 2. The liquid jet recording device according to claim 1, wherein the liquid introducing means is a suction pump. 3. According to claim 1, the moving means includes a capping knob that moves the cap in a direction to cover the orifice, and a spring that moves the cap in a direction away from the orifice. liquid jet recording device.