JPH0764151B2 - Valve device - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a valve device, and more particularly to a valve device used at a minute flow rate and a minute pressure such as those used for ink control of writing instruments.

[Prior Art] Conventionally, in ballpoint pens, felt pens, and the like that use water-based ink, a porous material such as cotton is filled in an ink storage chamber in a barrel of a writing instrument, and the ink is filled in the porous material. It was impregnated and held. However, in such a case, there is a problem that the amount of ink held is small, the amount of ink supplied is small, and the handwriting is faint when writing quickly.

In order to solve such a problem, a writing instrument for directly storing ink in a large-capacity ink storage chamber has been developed. In this product, a liquid-tight slide stopper is slidably inserted into the ink storage chamber, and the sliding of this slide stopper causes the ink to expand and
It is configured to compensate for contraction. Further, a sub-ink chamber having a small capacity different from the ink storage chamber is formed, and the sub-ink chamber communicates with a pen tip such as a ball tip or a felt tip. The ink storage chamber and the sub ink chamber communicate with each other via a check valve. This check valve
Allows only the flow of ink from the ink storage chamber to the sub ink chamber, and opens when the pressure difference between the ink storage chamber and the sub ink chamber exceeds a predetermined pressure difference, and the ink storage chamber is opened. Is configured to supply ink to the sub ink chamber.
In such a device, pressure fluctuations generated in a large-capacity ink storage chamber are shut off by this check valve to prevent ink dripping and air suction.

However, in such a writing instrument, the ball tip or felt tip is capable of sucking out the internal ink (the head pressure is about several hundreds of mm in pressure) at the time of writing, so that the check valve is opened and the slide stopper described above is used. Must be moved against its sliding resistance. Therefore, the above check valve needs to be opened with an extremely low differential pressure, for example, a differential pressure of about 100 mm. If the ink in the ink storage chamber contracts slowly over a long period of time, and if there is an extremely slight leak in the check valve, the ink in the sub-ink chamber will flow back into the ink storage chamber. Problems such as air being sucked in from the pen tip may occur.

Therefore, a valve device such as a check valve used for such a writing instrument must be one that operates accurately with a minute pressure and a minute flow rate and that internal leakage hardly occurs.
Of course, it is possible to manufacture such a valve device with conventional techniques. However, in the related art, the valve seat and the valve body of the valve device are manufactured separately and these parts are assembled. Therefore, these parts require extremely high processing accuracy. Moreover, since such a valve device is housed in the writing instrument, it must be formed in a small size. For this reason, great care must be taken in the manufacture of such valve devices, and 100% inspection is required to ensure quality. Therefore, conventionally, the manufacturing cost of such a valve device has been high. A writing instrument using such a valve device is generally of a disposable type, and its manufacturing cost must be as low as possible.

[Problems to be Solved by the Invention] The present invention has been made based on the above circumstances, and operates reliably and with high precision at a minute pressure and a minute flow rate, has almost no internal leakage, and is simple and low in manufacturing. It is an object to provide a valve device that can be manufactured at a cost.

[Means for Solving the Problem and Its Action] The present invention has a cylindrical valve body and a valve body that is filled in an uncured state and then cured, and has no adhesiveness to the valve body. A synthetic resin material having elasticity, for example, a valve body formed of silicone rubber or the like, and a valve shaft portion insertion hole is formed in the valve body along the axial direction.
A valve seat surface along a direction intersecting the axial direction is formed at a tip end portion of the valve body, and a base end portion of the valve body has at least a portion along a surface intersecting the axial direction. A main body side engaging portion is formed. A valve head, which is hardened after being filled on the valve seat surface, is integrally formed at the tip of the valve body, and the valve shaft insertion hole is formed in the center of the valve body. The valve shaft portion that is hardened in the filled state is integrally formed, and the valve body side engaging portion that is hardened in the main body side engaging portion is integrally formed at the base end portion of the valve body. Has been done. Therefore, the base end portion of the valve body is integrated with the valve body by the valve body side engaging portion and the main body side engaging portion, and the synthetic resin material forming the valve body is contracted during curing so that When the valve shaft portion contracts in the axial direction, the valve head portion is pressed against the valve seat surface by a predetermined small pressure, and when the valve shaft portion contracts in the radial direction, the outer circumference of the valve shaft portion. A gap for fluid flow of ink or the like is formed between the surface and the inner peripheral surface of the valve shaft insertion hole.

In such a valve device, a fluid such as ink is introduced from the base end surface of the valve body through the above-mentioned fluid passage gap, and when the pressure of this fluid becomes equal to or higher than a predetermined differential pressure, A gap is formed between the valve seat surface and the fluid, and the fluid flows through the gap to open the valve device.

In this valve device, the valve head is formed by filling the uncured synthetic resin on the valve seat surface of the valve body and hardening it, so it is possible to accurately handle even minute irregularities on this valve seat surface. As a result, the valve head is molded and closely contacts the valve seat surface, so that internal leakage hardly occurs. In addition, since this valve device presses the valve head against the valve seat surface with a slight pressure by utilizing a slight contraction when the synthetic resin material having elasticity such as silicone rubber is cured, the set valve opening pressure is It can be extremely small. In addition, this valve device has extremely high characteristics such as valve opening pressure even when it is mass-produced, even if it is mass-produced, if the shape of the valve body, the composition of the synthetic resin material forming the valve body, and other conditions are accurately adjusted. The valve device can be regulated accurately and the valve device with high accuracy can be mass-produced at low cost.

Also, according to a preferred embodiment of the present invention, the valve head is mounted on the valve seat surface while leaving a free surface which is not regulated by a mold, and is cured while leaving the free surface. It is made of synthetic resin.
Therefore, since distortion or the like due to contraction at the time of curing the synthetic resin material does not occur in the valve head portion, the valve head surely adheres to the valve seat surface and completely prevents internal leakage. Also, characteristics such as valve opening pressure become extremely accurate.

Further, according to the embodiment of the present invention, the main body side engaging portion is continuous with the inner peripheral surface of the valve shaft insertion hole and passes through the main body side engaging portion to form a base end surface of the valve main body. The reaching inner side surface portion is formed, and the synthetic resin material filled in the valve body side engaging portion is contracted at the time of curing to form a gap for fluid communication with the inner side surface portion. Therefore, the gap for fluid flow between the outer peripheral surface of the valve shaft portion and the inner peripheral surface of the valve shaft insertion hole surely communicates with the base end surface of the valve body through the gap between the inner surface portion. To do.

Furthermore, this valve device has a simple structure, and since it is not necessary to make the processing accuracy of parts and the like extremely high, the manufacturing cost is low, and the operation accuracy such as the valve opening pressure is high as described above. There is no need to test.

[Embodiment] An embodiment of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of the present invention. This embodiment is an application of the valve device of the present invention to a disposable felt tip pen using an aqueous ink.

In the figure, reference numeral 1 is a shaft cylinder of the pen, and a large-capacity ink storage chamber 2 is formed in the shaft cylinder 1 and liquid ink is filled in the interior thereof. A pen tip 3 is provided at the tip of the barrel 1. In this example,
The pen tip 3 is of a felt tip type, and the pen tip is composed of a felt tip 5 and a holder 4. Further, a small capacity sub-ink chamber 6 is formed on the tip end side of the shaft cylinder 1, and the sub-ink chamber 6 communicates with the pen tip 3 described above. The sub ink chamber 6 is communicated with the ink storage chamber 2 via the valve device 10 of the present invention, and ink is supplied from the ink storage chamber 2 to the sub ink chamber 6 via the valve device 10. It is configured to be.

A slide stopper 7 is slidably provided in the ink storage chamber 2. The slide stopper 7 is liquid-tight and separates the ink filled in the ink storage chamber 2 from the atmosphere. The slide plug 7 slides in response to the consumption of ink in the ink storage chamber 2 or the expansion and contraction of the ink, compensating for these and compensating for these.
The pressure of the ink inside is equilibrated with the atmospheric pressure. A tail plug 8 is attached to the tail end of the barrel 1, and an air communication passage 9 is formed in the tail plug 8.

The valve device 10 is a check valve that allows only the flow of ink in the direction from the ink storage chamber 2 to the sub ink chamber 6 and is configured to open with a small differential pressure. In this writing instrument, when the ink in the sub ink chamber 6 is consumed by writing, the valve device 10 is opened to supply the ink from the ink storage chamber 2 to the sub ink chamber 6, and the sub ink chamber 6 Keep the ink filled at all times. Further, in response to the consumption of ink in the ink storage chamber 2, the slide plug 7 slides to the left in the figure to compensate for the consumption of ink. The felt tip 5 has a function of drawing out the ink inside by the capillary phenomenon and holding the ink contained therein by the capillary phenomenon to maintain the seal. This ability is about 400 m under the head pressure.
It is about m. When writing, the valve device 10 is opened by the capillary force of the felt tip 5,
In addition, the slide stopper 7 overcomes the sliding resistance and slides. Further, when the ink in the ink storage chamber 2 expands or contracts due to a temperature change or the like, a positive pressure or a negative pressure is generated in the ink storage chamber due to the sliding resistance of the slide plug 7 described above. The negative pressure is shut off by the valve device 10 and is not transmitted to the pen tip 3. Further, when the pen is dropped on the floor or the like, a momentary positive or negative pressure is generated in the ink storage chamber 2 due to the impact. This negative pressure is blocked by the valve device 10 which is a check valve, and the positive pressure is greatly attenuated by the valve device 10, so that ink does not drop from the pen tip 3.

As described above, the valve device 10 must operate with a very small predetermined differential pressure and can reliably prevent internal leakage. In order to achieve such an object, this valve device is constructed as shown in FIGS. That is, the valve device 10 includes a valve body 11 and a valve body.
It consists of 12 and. The valve body 11 is made of a synthetic resin material and has a substantially cylindrical shape. The outer peripheral surface of the base end portion of the valve body 11 is expanded in diameter to form a mounting fitting portion 15. The mounting fitting portion 15 is the above-mentioned barrel 1.
The valve device is press-fitted to the inner surface of the valve while maintaining liquid tightness, and the valve device is fixed at a predetermined position. Inside the valve body 11, a valve shaft insertion hole 11b having a circular cross section, for example, is formed. In addition, a substantially conical valve seat surface 11a is formed at the tip of the valve body 11 so as to recede from the center toward the periphery toward the base end. A main body side engaging portion is formed at the base end portion of the valve main body 11. The main body side engaging portion includes a step portion 11d formed in the base end portion of the valve main body 11, and the step portion 11d is a surface in a direction intersecting the central axis of the valve shaft insertion hole 11b. For example, it is formed in a plane orthogonal to the central axis or a conical surface forming a predetermined angle with the central axis. Further, the main body side engaging portion is formed with four engaging convex portions 11c projecting axially rearward from the step portion 11d. The rear end portions of these engaging convex portions 11c reach the base end surface portion of the valve body 11, and the inner side surface portion 21 of these engaging convex portions 11c is the inner circumference of the valve shaft insertion hole 11b. It is continuous to the surface.

The valve body 12 is made of an elastic synthetic resin material such as silicone rubber. Moreover, the synthetic resin material forming the valve body 12 does not have adhesiveness to the valve body 11. The valve body 12 is obtained by filling and assembling the uncured silicone rubber into the inside of the valve body 11, that is, the valve body fixing portion and the valve seat surface, and then curing the silicone rubber. Therefore, this valve body 12 is
It is formed in a shape corresponding to the inner shape of 11.

The valve body 12 is integrally formed with a valve shaft portion 12b which is hardened in a state of being filled in the valve shaft insertion portion 11b of the valve body 11, and the valve shaft portion 12b has the valve shaft insertion hole 11b. It has a cylindrical shape corresponding to.

A valve head 12a is formed at the tip of the valve body 12. The valve head 12a is placed on the valve seat surface 11a in an uncured state with the synthetic resin material forming the valve body 12 in a state where the tip of the valve body 11 is directed upward, and the valve head 12a is left as it is. It has been cured. It should be noted that this arranging means filling without using a mold or using a mold whose part is opened, and filling and curing while leaving a free surface. Therefore, the valve head portion 12a has a raised substantially spherical tip surface and is in close contact with the valve seat surface 11a.

Further, a valve body side engaging portion 12c is formed at the base end portion of the valve body 12. This valve body side engaging portion 12c is inside the main body side engaging portion, that is, between the inner peripheral surface of the base end portion of the valve body whose diameter is expanded by the step portion 11c and the engaging convex portion 11c. It is formed by a portion that wraps these filling protrusions 11c and is filled and hardened.

When the silicone rubber forming the valve body 12 cures, a slight contraction occurs. Therefore, each part of the valve body 12 contracts in the axial direction and the radial direction.

Therefore, the valve shaft portion 12b also contracts in the axial direction,
Since the base end portion of the valve body 12 is mechanically integrated with the valve body 11 by the valve body side engaging portion 12c and the main body side engaging portions 11c and 11d, the axial direction of the valve shaft portion 12b Due to the contraction, the valve head 12a is pressed against the valve seat portion 11a with a predetermined pressure. In this state, a slight tensile stress is generated in the valve shaft portion 12b, and the elastic force of the valve shaft portion 12b causes the valve head portion 12a to exert a slight pressure on the valve seat portion 11a. It is being pressed.

Further, due to the radial contraction of the valve shaft portion 12b, between the outer peripheral surface of the valve shaft portion 12b and the inner peripheral surface of the valve shaft insertion hole 11b,
A gap 20 is formed, and this gap 20 is formed as a passage through which a fluid, that is, ink, flows. Also, the above-mentioned engaging protrusion
Similarly, a gap 22 is formed between the inner side surface portion 21 of 11c and the inner side surface portion 21 by radial contraction. Inner side surface 2 of this engaging protrusion 11c
Since 1 is continuous with the inner peripheral surface of the valve shaft insertion hole 11b, this gap 22 is also continuous with the gap 20 described above, and these gaps 20 and 22 are formed as ink circulation passages, and through these, Ink flows from the base end surface of the valve body 11 to the valve head 12a and the valve seat surface 11a.

In the valve device 10 formed in this way, the back surface of the valve head 12a is in a male or female relationship with the valve seat surface 11a.
The valve head 12a faithfully corresponds to the minute unevenness on the valve seat surface 11a, so that no gap is formed between them and they are completely in close contact with each other. Also,
Since the valve head 12a of the valve body 12 is hardened in the as-assembled state, there is no internal stress inside the valve head 12a, and the valve head 12a is firmly adhered, so internal leakage must be completely prevented. You can

In such a valve device, when the pressure difference between the ink storage chamber 2 and the sub ink chamber 6 becomes equal to or more than a predetermined pressure difference, the valve shaft portion 12b slightly expands due to this pressure, and the valve head portion A small gap is formed between the valve seat 12a and the valve seat portion 11a, and the valve is opened to allow the ink to flow into the sub ink chamber 6. Further, this valve device acts as a check valve when the pressure in the sub ink chamber 6 becomes high, and prevents the reverse flow of ink.

The present invention is not limited to the above embodiment. For example, FIGS. 4 and 5 show a second embodiment of the present invention. In this embodiment, the base end of the valve main body 11 has a main body side engaging portion having a stepped portion 31d and the diameter is increased, and the base end of the valve body 12 has the main body side engaging portion. It is provided with a valve body side engaging portion 32c which is filled and hardened. Also, when filling the uncured silicone rubber into the valve body 11,
Insert 11 into the mold 33.
Is formed, and the height of the convex portion 34 is set such that the tip thereof reaches the inner peripheral surface of the valve shaft insertion hole 11b of the valve body 11. Therefore, the filled silicone rubber has a passage portion 35 formed in the convex portion 34, and the passage portion 35 reaches the inner peripheral surface of the valve shaft insertion hole 11b, that is, the gap 20 forming the ink passage. Then, the ink is introduced into the gap 20 via the passage portion 35.

Also, FIGS. 6 and 7 show a third embodiment of the present invention. This has a valve shaft insertion hole 11b at the base end of the valve body 11.
A main body side fitting hole 41d that is orthogonal to the above is formed, and the base end portion of the valve body 12 is filled and cured inside the valve body side engaging portion.
42c is integrally formed. The valve shaft portion 12b is extended to the base end portion of the valve body 11, and a gap 2 formed between the outer peripheral surface of the valve shaft portion 12b and the inner peripheral surface of the valve shaft insertion hole 11b.
0 opens at the base end surface of the valve body 11. Reference numeral 43 is a mold used for filling the silicone rubber.

Further, FIGS. 8 and 9 show a fourth embodiment of the present invention. In this embodiment, four main body side engagement grooves 51d radially arranged are formed at the base end portion of the valve main body 11.
Further, the main body side engagement groove 51d is formed in the base end portion of the valve body 12 described above.
Further, the valve body side engaging portion 52c which is filled and hardened in the cavity surrounded by the mold 53 is integrally formed. The valve stem 1
The gap 20 formed between the outer peripheral surface of 2b and the inner peripheral surface of the valve shaft insertion hole 11b includes a main body side engaging portion 51d and a valve body side engaging portion 52c.
An opening is made in the base end surface of the valve body 11 through a portion between the two.

Further, FIGS. 10 to 12 show a fifth embodiment of the present invention. In this structure, a step portion 61d is formed at the base end portion of the valve body 11 to form a main body side engagement portion including a diameter expansion portion 65 having an enlarged diameter. Further, a plurality of tapered rib grooves 66, for example, four rib grooves 66 are formed from the inner peripheral surface of the expanded diameter portion 65 to the inner peripheral surface of the central portion of the valve shaft insertion hole 12b. Also,
The valve body 12 has a shape corresponding to the inner shape of the valve body 11, a valve body side engaging portion 62 corresponding to the main body side engaging portion is formed, and also corresponds to the rib groove 66. Rib part
67 is formed. Then, due to the contraction of the silicone rubber forming the valve body 12 at the time of curing, the expanded diameter portion 65 is formed.
A gap 69 is formed between the inner peripheral surface of the rib and the outer peripheral surface of the valve body side engaging portion 62c, and a gap is also formed between the bottom surface of the rib groove 66, that is, the inner side surface portion and the top surface of the rib portion 67. Has been formed.
Further, the above-mentioned gap 69 is provided with the valve shaft insertion hole 11b through the gap 68.
Is communicated with the intermediate portion of the gap 20 between the inner peripheral surface of and the outer peripheral surface of the valve shaft portion 12b. Therefore, this gap 20 is the above-mentioned gap.
The valve body 11 is opened at 68 through 69, and the ink is circulated through these gaps.

The second to fifth embodiments described above are the same as the first embodiment except for the above-mentioned configuration, and the first embodiment in FIGS. The parts corresponding to the examples are denoted by the same reference numerals, and the description thereof will be omitted.

The present invention is not limited to the above embodiments. For example, the shapes and configurations of the valve body, the valve seat surface, the valve body side engaging portion, the valve body side engaging portion, etc. are not limited to those described above, and can be appropriately set according to the application and the like. The elastic material forming the valve body is not limited to silicone rubber, and other synthetic resin materials having elasticity can be used. Further, the present invention is not limited to the valve device used for the writing instrument, and it goes without saying that the present invention can be applied to the valve device used for other purposes.

[Advantages of the Invention] According to the present invention, a valve seat surface and a main body side engaging portion are formed in a valve main body, an uncured elastic resin is placed inside the valve main body, and the resin is cured to form a valve body. It is composed. Therefore, the valve head portion of this valve body is formed into a shape that faithfully corresponds to the unevenness of the valve seat surface, and is completely in close contact with this valve seat surface without any gap. Therefore, internal leakage hardly occurs. Also, the valve shaft part contracts in the axial direction due to the slight contraction when the synthetic resin material forming the valve body hardens, and the valve head part is pressed against the valve seat surface with a predetermined small pressure, and with a small pressure. An accurate valve device that opens the valve is obtained. This structure has a simple structure and can achieve extremely accurate and stable valve opening operation only by adjusting and setting the shape of the valve body, the characteristics of the material of the valve body, and the like. Therefore, a valve device having a small valve operating pressure and a small flow rate can be manufactured at low cost and with high reliability.

[Brief description of drawings]

1 to 3 show a first embodiment of the present invention. FIG. 1 is a vertical sectional view of the whole writing instrument, FIG. 2 is a vertical sectional view of a valve device, and FIG. 3 is III of FIG. It is a sectional view taken along the line III.
4 to 5 show a second embodiment, FIG. 4 is a longitudinal sectional view of the valve device, and FIG. 5 is a sectional view taken along the line VV of FIG. 6 and 7 show a third embodiment,
FIG. 6 is a longitudinal sectional view of the valve device, and FIG. 7 is VII-VII of FIG.
It is sectional drawing which follows the line. FIGS. 8 and 9 show a fourth embodiment, FIG. 8 is a longitudinal sectional view of the valve device, and FIG.
It is sectional drawing which follows the IX-IX line of a figure. 10 to 12 show a fifth embodiment, and FIG. 10 is a longitudinal sectional view of a valve device,
11 is a sectional view taken along line XI-XI in FIG. 10, and FIG. 12 is a sectional view taken along line XII-XII in FIG. 10 …… Valve device, 11 …… Valve body, 11a …… Valve seat surface, 11b ……
Valve shaft insertion hole, 11c ... Engaging protrusion (main body side engaging object), 11d ...
… Step (main body side engaging part), 12 …… Valve disc, 12a …… Valve head, 12b …… Valve shaft, 12c …… Valve disc side engaging part, 20 …… Gap (fluid flow passage)

Claims (3)

[Claims] 1. A valve body having a cylindrical shape, a valve shaft insertion hole is formed in the valve body along an axial direction, and a tip end portion of the valve body is provided along a direction intersecting the axial direction. A valve seat surface is formed, and a main body side engaging portion having a surface along a direction intersecting the axial direction is formed at least at a base end portion of the valve main body. Is provided with a valve body formed by filling an uncured synthetic resin material that is non-adhesive with the valve body in an uncured state and then cured. The valve head that is hardened after being filled on the surface is integrally formed, and the valve shaft that is hardened while being filled in the valve shaft insertion hole is integrally formed at the center of the valve body. Further, the valve body side engaging portion which is hardened in the state of being filled in the main body side engaging portion is provided at the base end portion of the valve body. When the synthetic resin material forming the valve body is contracted during curing, the valve shaft portion contracts in the axial direction, so that the valve head portion becomes the valve seat surface. It is characterized in that a gap for fluid flow is formed between the outer peripheral surface of the valve shaft portion and the inner peripheral surface of the valve shaft insertion hole by being pressed and contracting in the radial direction of the valve shaft portion. Valve device. 2. The valve head is formed of a synthetic resin which is mounted on the valve seat surface while leaving a free surface which is not regulated by a mold and which is cured while leaving the free surface. The above-mentioned claim 1 characterized in that
The valve device described. 3. The main body side engaging portion is formed with an inner side surface portion which is continuous with the inner peripheral surface of the valve shaft insertion hole and passes through the main body side engaging portion to reach the base end surface of the valve main body. 2. The valve device according to claim 1, wherein a gap for fluid flow is formed between the synthetic resin material filled in the valve body side engagement portion and the inner side surface portion due to contraction during curing. .