JP2002202066A - Liquid delivery device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid delivery device capable of accurately delivering an extremely trace quantity of liquid, easy in handling, capable of eliminating partial abrasion of a seal, and capable of miniaturizing a pump block. SOLUTION: This liquid delivery device has a valve block 35, the pump block 50 capable of slidingly contacting with a sliding contact surface 38 of the valve block 35, and a plunger 55 slidingly inserted in the shaft direction into a plunger inserting hole 53 of the pump block 50. The plunger inserting hole 53 has a seal part 531B for sealing a part between the plunger 55 and the plunger inserting hole 53, and a guide part 531A for guiding the plunger 55. The seal part 531B is formed in a lip shape by a groove 531C, and an inner diameter of a lip part is formed smaller than an outer diameter of the plunger 55, and is composed of elastic PTFE or the like. Since the seal part 531B is integrally formed in the pump block 50, the handling is facilitated, and assembling workability can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid ejecting apparatus for sucking and ejecting a liquid by utilizing a reciprocating motion of a plunger, and more particularly to a dispenser for repeatedly ejecting a liquid at a predetermined amount, and a continuous supply of the liquid. Available for pumps.

[0002]

2. Description of the Related Art As this type of liquid ejection apparatus, there is one described in Japanese Patent Application Laid-Open No. 9-324743 filed by the present applicant. The liquid discharge device includes a valve block having a sliding contact surface having a communicating hole communicating with a suction port and a discharge port, and a body having a sliding contact surface at one end in contact with the sliding contact surface of the valve block. A pump block having a plunger insertion hole formed in the axial direction at a position communicable with the opening of the communication hole of the valve block, and biasing the pump block toward the valve block. While rotating, the plunger insertion holes are sequentially communicated with the communication holes, and the plungers in the plunger insertion holes are each driven in the axial direction to sequentially repeat the suction and discharge of the liquid.

At this time, in the liquid discharging apparatus described in Japanese Patent Application Laid-Open No. 9-324743, since the valve block and the pump block are arranged in the container, a special seal is provided between the plunger insertion hole of the pump block and the plunger. However, the liquid leaking from the meantime is configured to return to the container.

On the other hand, a container may not be used depending on the type of liquid or the like. In such a case, it is necessary to provide a plunger seal between the plunger insertion hole and the plunger to prevent leakage. There is. As such a seal, an O-ring usually formed of rubber or the like, or a seal having a structure in which a resin material is brought into contact with a plunger with a metal spring has been used. Then, a seal arrangement groove for disposing a seal material is formed in the pump block, a seal is arranged in this groove, and the seal is brought into close contact with the plunger for sealing.

[0005]

The seal provided on the outer periphery of such a plunger can be used without any problem in a general liquid discharging apparatus, but particularly in a liquid discharging apparatus which discharges a very small amount of liquid, There was such a problem.
That is, in a liquid ejection device that ejects a very small amount of liquid,
Each part such as pump block and plunger is also very small. Therefore, seals such as O-rings and seal arrangement grooves were also small.

There is a problem in that such a small seal is difficult to handle, and the work of incorporating the seal into the seal arrangement groove or the like is complicated. Also, the diameter of the seal arrangement groove is slightly smaller than the outer periphery of the seal so that the seal such as an O-ring can be pressed slightly and brought into close contact with the plunger.
On the other hand, the width (length in the axial direction of the plunger) of the seal arrangement groove is larger than the thickness of the seal. For this reason, there is also a problem that the seal slightly moves in the axial direction of the plunger in the seal arrangement groove. In particular, in the case of a very small amount of discharge, even a slight change in the amount of discharge due to the movement of the seal has a large effect of the error, and there is a problem that it is difficult to discharge a very small amount of liquid with high accuracy.

Further, since the seal is sandwiched between the seal arrangement groove of the pump block and the plunger, there has been a problem that a misalignment between the seal and the plunger insertion hole for guiding the plunger occurs. In addition, the seal needs to have a certain minimum size for handling, and there is a limit to the miniaturization of the seal and the seal arrangement groove. Therefore, it is necessary to make the pump block a certain size in order to form the liquid ejecting apparatus, and there is a problem that it is difficult to reduce the size of the liquid ejection device. In particular, if it is difficult to reduce the size of the pump block, it is also difficult to reduce the size of the driving mechanism for driving the pump block, and it is also difficult to reduce the manufacturing cost.

SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid discharging apparatus capable of discharging a very small amount of liquid with high precision, being easy to handle, eliminating unevenness in seal wear, and realizing a compact pump block. To provide.

[0009]

According to the present invention, there is provided a liquid ejecting apparatus, comprising: a valve block having a sliding contact surface; a pump block having a sliding contact surface capable of contacting the sliding contact surface of the valve block; A plunger axially slidably inserted into at least one plunger insertion hole formed in the axial direction of the plunger, urging means for urging the pump block toward the valve block, and the pump block. Rotation driving means for rotationally driving, a plunger advance and retreat driving means for driving the plunger to advance and retreat in the axial direction,
The valve block has a discharge port communicating with a discharge opening formed in the sliding contact surface and a discharge port formed on an outer surface facing the sliding contact surface, and a suction opening formed in the sliding contact surface. And a suction port communicating with a supply port opened on the liquid supply side, and a plunger insertion hole of the pump block is provided at a position communicable with a discharge opening and a suction opening of the valve block along an axial direction. And a seal portion formed integrally with the pump block for sealing between the plunger and the plunger insertion hole.

[0010] In the present invention, since the seal portion is formed integrally with the pump block in which the plunger insertion hole is formed, the entire pump block is required as compared with the conventional case where a separate sealing member is used. Therefore, even if the seal portion is small, the handling becomes easy and the assembling workability can be improved. In addition, since the seal portion is formed integrally with the pump block, no error occurs due to a change in the discharge amount due to the movement of the seal material, and even a very small amount of liquid can be discharged with high precision. it can. further,
Since the seal is integral with the pump block, misalignment with the plunger insertion hole can be prevented. Further, since there is no need to handle the seal alone and to form the seal arrangement groove, it is possible to minimize the size of the pump block. For this reason, the drive mechanism for driving the pump block can be reduced in size, the size of the entire liquid ejection apparatus can be reduced, and the manufacturing cost can be reduced.

In this case, the seal portion is formed in a lip shape by forming a groove which leaves a predetermined thickness from the inner peripheral surface of the plunger insertion hole and communicates with the opening of the plunger insertion hole on the valve block side. The inner diameter of the lip portion is preferably smaller than the outer diameter of the plunger, and is preferably made of a material having elasticity.

As described above, if the seal portion is formed in a lip shape, a groove communicating with the plunger insertion hole is formed on the outer peripheral side of the lip portion, and the seal portion is made of an elastic material, the inner diameter of the plunger is reduced. The seal portion slightly smaller than the outer diameter can be brought into contact with the plunger with an appropriate elastic force. Further, since the groove communicates with the opening on the valve block side, when liquid exists in the plunger insertion hole, a part of the liquid flows into the groove. When the pressure of the liquid is high, such as when the plunger is pushed out to the valve block to discharge the liquid, the pressure of the liquid in the groove also increases, and the seal is attached to the plunger with a larger force. Force and abut. Conversely, when the pressure of the liquid is low, as in the case where the liquid is sucked by pulling the plunger, the pressure of the liquid in the groove also decreases, and the force for urging the seal portion against the plunger also decreases. Therefore, since the seal portion can have a so-called self-sealing structure, the contact force of the seal can be increased when the pressure of the liquid increases and the seal performance needs to be improved, and the seal performance can be improved.
On the other hand, when the pressure of the liquid is low and the sealing can be performed without pressing the seal portion so much against the plunger, the urging force can be reduced to reduce the frictional force. Therefore, as compared with the case where the seal portion is always in contact with the plunger under the same pressure, reliable sealing performance can be ensured and wear of the seal portion can be reduced.

At this time, the outer diameter of the plunger is 0.3 to
The inner diameter of the plunger insertion hole is +0.01 to +0.1 with respect to the set outer diameter of the plunger.
0 mm, the inner diameter of the seal portion is in the range of -0.01 to -0.50 mm with respect to the set outer diameter of the plunger, and its absolute value is larger than the gap between the plunger insertion hole and the plunger. It is preferably set to a value.

If the outer diameter of the plunger is as small as about 0.3 to 5 mm, a very small amount of liquid can be discharged by adjusting the stroke amount. In addition, if the outer diameter of the plunger is small, it is very difficult to dispose the O-ring as in the prior art. However, according to the present invention, the seal is integral with the pump block, so that the installation is easy. is there. For this reason, the present invention is very effective especially when the outer diameter of the plunger is very small, such as about 2 mm or less.

The inside diameter of the plunger insertion hole, that is, the inside diameter of the guide portion for guiding the plunger in the plunger insertion hole may be any size as long as the plunger can be inserted. 01 ~
It may be set within a range of about +0.10 mm. In addition, this dimension is set according to the tolerance (machining accuracy) permitted by a processing machine that drills a plunger insertion hole so that the plunger can be securely inserted.

Further, the inner diameter of the seal portion may be set to a size capable of securely contacting the plunger, and is usually in the range of -0.01 to -0.50 mm with respect to the outer diameter of the plunger. What is necessary is just to set it to a value whose size is larger than the gap between the inner surface of the plunger insertion hole and the plunger. With this configuration, even when the plunger is shifted to one side of the plunger insertion hole, the seal portion can be reliably brought into contact with the outer peripheral surface of the plunger. Therefore, if each dimension is set to the above-mentioned size, reliable sealing performance can be obtained, and wear of the seal portion can be suppressed to a minimum. Note that the inner diameter of the seal portion may be set by a spring constant determined particularly by the shape of the seal portion. For example, when the spring constant is small, such as when the seal is formed in a lip shape, the amount of displacement of the seal can be increased, so that the protrusion dimension of the seal (the difference between the outer diameter of the plunger and the inner diameter of the seal) is also large. Yes, for example -0.05
About -0.50 mm. On the other hand, when the seal portion is not formed in a lip shape and there is no groove or the like that can absorb the deformation when the seal portion is deformed, the spring constant also increases, so the displacement amount of the seal portion also decreases. , That much,
The protrusion size of the seal portion (difference between the outer diameter of the plunger and the inner diameter of the seal portion) also needs to be reduced.
It must be about 0.05 mm.

The pump block can be made of various engineering plastics which are excellent in friction and wear resistance and slidability, and have good chemical resistance and the like. In particular, the pump block is made of a crosslinked fluororesin or polyamideimide. Is preferred. It is particularly preferable that the crosslinked fluororesin is composed of crosslinked polytetrafluoroethylene (PTFE).

If a cross-linking type fluororesin is used, the elasticity of the spring is increased by the cross-linking, so that the seal portion can be made to have an elastic force. In this case, an appropriate sealing force can be obtained. In addition, fluororesins such as polytetrafluoroethylene have excellent chemical resistance and can be used for discharging various liquids. In addition, since the friction coefficient is small and the wear resistance is excellent, the service life can be prolonged, and it is particularly suitable as a material of the pump block of the present invention in which the seal portion is integrally formed.

On the other hand, when a polyamideimide is used, it is excellent in friction and wear resistance, chemical resistance and the like, and further excellent in impact resistance and the like, and can support a larger load, like the fluororesin.

In order to seal even when the plunger is at the stroke end position when the plunger strokes away from the valve block, the plunger at the stroke end position is closer to the stroke direction (farther from the valve block) than the tip of the plunger. Preferably, the seal portion is formed. In this case, when the plunger is driven, the seal portion can always contact and guide the plunger, so that the plunger hits the seal portion as in the case where the plunger is separated from the seal portion and inserted again. Damage to the seal portion can be reliably prevented.

Further, the seal portion is arranged in a ring shape around the plunger insertion hole, and is pressed by pressing means to abut on the outer peripheral surface of the plunger. Good.

In such a configuration, the above-mentioned effect can be obtained by the seal portion being integrally formed with the pump block. In addition, since the seal portion can be brought into contact with the plunger by the pressing means, the sealing can be performed. There is no need to contact the plunger with the elastic force of the seal itself,
The seal portion, that is, the pump block can be made of a member having no elastic force. For this reason, as a material of the pump block, for example, an ethylene tetrafluoride copolymer (trade name: Teflon) to which a general filler such as carbon or glass fiber is added can be used. Therefore, the limitation of the material to be used is reduced, and the pump block can be manufactured from an appropriate material in consideration of other characteristics, cost, and the like, and can be easily and inexpensively manufactured.

Further, when the sealing mechanism is constructed by securing a predetermined contact force by the elastic force of the sealing portion itself, the dimension of the inner diameter of the sealing portion must be suppressed to a predetermined range. , The dimensional accuracy of the seal is not so required.
Also in this respect, it can be easily manufactured.

In this case, the pump block includes a pump block main body, and a rotary seal disk which is prevented from rotating with respect to the pump block main body and can rotate integrally with the pump block main body. And the pressing means is preferably formed by an O-ring that is interposed between the pump block main body and the rotation-side seal disk and is in contact with the outer peripheral surface of the seal portion.

If an O-ring is used as the pressing means, the cost can be reduced and the gap can be filled with the O-ring, so that the dead space can be reduced and the inflow and stagnation of the liquid to be discharged can be reduced. Also, since the O-ring is made of rubber or the like and has elasticity, when the seal is pressed, the O-ring itself is appropriately deformed, so that the pressure applied to the seal can be appropriately controlled, and the contact between the seal and the plunger can be controlled. The contact pressure can be easily controlled within an appropriate range. In addition, when the pump block is composed of the pump block main body and the rotating side seal disk, it is necessary to seal the liquid so as not to leak out between these members. Can be used for
The number of parts can be reduced and assemblability can be improved. further,
Since the O-ring itself is not used as a seal,
It is possible to prevent the problems that occur when a conventional O-ring is used as a seal, for example, problems such as reduced handleability, axial movement of the seal, and misalignment.

[0026]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a front view of a dispenser 1 which is a liquid ejection apparatus according to a first embodiment of the present invention. A dispenser 1 includes a drive unit 2 having a built-in drive mechanism.
And a pump section 3.

As shown in FIG. 2, the drive unit 2 includes a body 10 formed of a plurality of plates or blocks in a box shape.
And a motor 11 fixed to the body 10. As the motor 11, a servo motor, a stepping motor, or the like is used.
7, or a motor that can be controlled for each rotation using a position detection sensor such as an encoder built in the servo motor.

A substantially cylindrical rotation interlocking member 12 is fixed to the output shaft of the motor 11. As shown in FIG. 4, the rotation interlocking member 12 has a notch 1 in one place.
The notch 12B passes through the rotation position detection sensor 17 by the rotation position detection sensor 17 disposed on the flange 12A, so that the rotation interlocking member 12, ie, the motor is formed. 1
One rotation of one can be detected. In addition, the peripheral surface of the lower part (the tip part) of the rotation interlocking member 12 is
As shown in FIG. 3, three rollers 13 are supported by the shaft.
The rollers 13 are arranged on the peripheral surface of the rotation interlocking member 12 at a center angle of 120 degrees.

A pump drive shaft 60 rotatably supported on the body 10 is disposed on the axis of the rotation interlocking member 12 and the motor 11. The pump drive shaft 60 is
As shown in FIGS. 2 and 3, the drive unit-side drive shaft 60 </ b> A extending from the drive unit 2 to the pump unit 3 and disposed in the drive unit 2, and the pump unit side disposed in the pump unit 3 It is formed so as to be separable from the drive shaft 60B. Thereby, when removing the pump unit 3 from the drive unit 2 such as when cleaning the pump unit 3, the pump unit-side drive shaft 60B can be removed together with the pump unit 3.

The upper end of the drive unit side drive shaft 60A (the motor 11
On the (side), a rotary transmission member 15 having a substantially cylindrical shape and formed with three guide grooves 15A through which the rollers 13 are guided is fixed. By arranging the roller 13 in the guide groove 15A of the rotation transmission member 15, the pump drive shaft 60 can advance and retreat in the axial direction with respect to the rotation interlocking member 12, that is, the motor 11 (movable up and down).
In addition, the rotational force of the motor 11 is transmitted as it is and rotates with the rotation interlocking member 12.

As shown in FIG. 5, a fixed shaft 21 which is adjacent to the drive unit side drive shaft 60A and is orthogonal to the shaft 60A is attached to the body 10. A guide member 20 formed in a substantially square plate shape is rotatably supported on the fixed shaft 21. As shown in FIG. 6, the guide member 20 has a through hole 22 in which the pump drive shaft 60 can be inserted.
A letter-shaped notch 23 is formed. On the lower surface of the guide member 20 (the surface on the side of the pump section 3), a roller guide 24 having a semicircular cross section around the through hole 22 and a ring shape (circular shape) arranged around the through hole 22 is provided. It is formed integrally. In the notch 23,
A contact shaft 25 parallel to the fixed shaft 21 is attached.

A contact member 82 contacts the upper surface of the contact shaft 25. The contact member 82 includes a main body that is in contact with the contact shaft 25 and a screw that is screwed to the main body. On the upper surface of the screw, the spindle 81 of the micrometer 80 fixed to the body 10 is provided. Have been abutted. On the other hand, an urging member 86 that is urged upward (toward the motor 11) by a coil spring 85, which is urging means disposed in the body 10, is in contact with the lower surface of the contact shaft 25.

Accordingly, the contact shaft 25 is constantly urged upward by the urging member 86, and the operating knob of the micrometer 80 is turned to move the spindle 81 forward and backward (vertically move), thereby causing the contact member 82 to move. When moved up and down, the contact shaft 25 also moves up and down in conjunction with the movement, and as a result, the guide member 20 can rotate about the fixed shaft 21 as a fulcrum to adjust the inclination angle. For this reason, in the present embodiment, the micrometer 80, the contact member 82, the coil spring 85, and the urging member 86 constitute a discharge amount setting unit.

In this embodiment, the guide member 20 is orthogonal to the pump drive shaft 60, that is, the pump drive shaft 6
If 0 is arranged along the vertical direction, the guide member 20
Is horizontal, the lower end of the urging member 86 is
Is set to abut. For this reason, the guide member 20 has the fixed shaft 21 and the contact shaft 25 at the same height position,
In other words, from the horizontal state, the contact shaft 25 is located above the fixed shaft 21, that is, the contact shaft 25 side is moved upward and the guide member 20 is inclined. Further, by changing the screwing position of the screw of the contact member 82, when the guide member 20 is in a horizontal state, the scale of the micrometer 80 is set to “0” (reference position). The dimensions are adjusted.

The roller guide 24 of the guide member 20 includes
A roller 65 which is a driven part fixed to the driving part side driving shaft 60A is in contact with the driving part 60A. The roller 65 is biased upward (toward the motor 11) by a coil spring (biasing means) 56, which will be described later.
4 is always in contact. Therefore, when the motor 11 and the pump drive shaft 60 rotate, the roller 65 moves along the roller guide 24. At this time, if the guide member 20 is horizontal, the pump drive shaft 60 does not move up and down.
Is inclined, the roller 65 moves up and down along the roller guide 24, and the pump drive shaft 60
Also moves up and down while rotating.

As shown in FIG. 3, the pump unit 3 has a case 30 detachably attached to the cylindrical connecting member 5 screwed to the body 10 of the drive unit 2 by a cap nut 31. The case 30 is made of stainless steel, fluororesin, titanium, or the like, and is formed in a substantially cylindrical shape. The connecting member 5 rotatably supports the pump unit side drive shaft 60B.

At the lower end of the case 30, a stainless steel valve block 35 which also functions as a fixed-side seal disk is screwed. As shown in FIGS. 7 to 9, the valve block 35 is formed in a stepped disk shape with a convex cross section, and has a smooth sliding contact surface 38 facing the inside of the case 30.
A tapered surface 39 and a side surface 39 </ b> A formed continuously with the sliding contact surface 38 and exposed in the case 30 are provided.
Also, a part of the circumferential surface of the large diameter portion of the valve block 35
As shown in FIG. 8, a vertical connection surface 36 is provided.

Further, the valve block 35 has a discharge port 41 penetrating in the axial direction from a discharge opening 40 formed in the sliding contact surface 38, and a suction opening 4 formed in the sliding contact surface 38.
A suction port 42 penetrating obliquely from 3 toward a supply port 44 formed in the connection surface 36 is formed. The diameter of the discharge opening 40 and the suction opening 43 is larger than the diameter of the discharge port 41 and the suction port 42.

As shown in FIG. 10, a discharge nozzle 45 having a discharge needle 46 is screwed to the lower surface of the valve block 35, and the liquid 7 discharged from the discharge port 41 passes through the discharge nozzle 45. The ink is discharged from the discharge needle 46.

As shown in FIGS. 1 and 3, a container 90 is connected to the connection surface 36 of the valve block 35 via a container connecting member 91. That is, the container connecting member 91
Is connected to a connecting portion 92 to which the container 90 is connected.
And a liquid supply passage 93 for supplying the liquid 7 by communicating from the supply port 44 to the supply port 44, and is bolted to the connection surface 36. A drain port 30A for discharging the liquid leaking into the case 30 is formed on the side surface of the case 30 as needed.

A pump block 50 having a substantially cylindrical shape as a whole is disposed adjacent to the valve block 35 in the case 30. The pump block 50 includes a pump block main body 50A, and a rotation-side seal disk 50B which is prevented from rotating with respect to the pump block main body 50A by a pin 50C and can rotate integrally with the pump block main body 50A.

At the lower end of the pump block 50 (the lower surface of the rotating side seal disk 50B), a smooth sliding contact surface 51 which is in sliding contact with the sliding contact surface 38 of the valve block 35 which is also a fixed side seal disk is formed. . In the present embodiment, the pump block main body 50A is made of a material having chemical resistance, a small coefficient of friction, abrasion resistance, and a spring property (elasticity). In particular,
It is a cross-linked fluororesin, more specifically, a cross-linked type polytetrafluoroethylene (PTFE). The rotation-side seal disk 50B is made of a super engineering plastic such as polyamideimide or ceramic, and the valve block 35 is made of stainless steel. The sliding contact surface 38 of the valve block 35
Is coated with a diamond-like carbon film (DLC), and has a structure that satisfies both the sealing property and the sliding property when sliding on the sliding surface 51 and has excellent durability.

As shown in FIG. 8, two rotation transmitting rods 62 are engaged and fixed to a large diameter portion 61 formed at the lower end of the pump drive shaft 60. That is, on the outer peripheral surface of the large diameter portion 61, two engagement grooves 63 are formed in the axial direction of the large diameter portion 61, and one engagement groove 64 is formed in the circumferential direction. The rotation transmission rod 62 is also formed with a groove 62A that matches the engagement groove 64.
2 is disposed in each of the engagement grooves 63, and a locking member such as a C-ring 66 having a spring property is engaged with the engagement groove 64 and the groove 62A. Diameter 6
1 is detachably fixed.

At the upper end of the pump block 50, an engagement groove 52 is formed in which the two rotation transmitting rods 62 are engaged. Thus, when the pump drive shaft 60 rotates, the pump block 50 rotates via the rotation transmission rod 62 and the engagement groove 52. A pin 62B is provided at the lower end of the rotation transmission rod 62 so as to project in the direction perpendicular to the axis, so that the rotation transmission rod 62 moves up and down relative to the pump block 50 within the range of the side cutout of the pump block 50. Have been able to.

As shown in FIG. 7, a single plunger insertion hole 53 is formed in the pump block 50 so as to penetrate the pump block 50. Specifically, the plunger insertion hole 53 is formed through the pump block main body 50A, and is formed through the rotation side seal disk 50B and has a larger diameter than the plunger insertion hole 531. And a plunger insertion hole 532. The plunger insertion hole 53 is formed at a position where it can communicate with the discharge opening 40 and the suction opening 43 of the valve block 35 as the pump block 50 rotates.

The plunger insertion hole 531 has a guide portion 531 for guiding the plunger 55 inserted into the hole 53.
A, and a seal portion 531B for sealing between the plunger 55 and the plunger insertion hole 531. The guide portion 531A is formed with an inner diameter capable of guiding the plunger 55 smoothly and without rattling. For example, the inner diameter of the guide portion 531A is formed to have a size in the range of +0.01 to +0.10 mm with respect to the outer diameter of the plunger 55.

The seal portion 531B is provided with the plunger insertion hole 5
By forming a groove 531C communicating with the opening of the plunger insertion hole 531 on the valve block side, that is, the plunger insertion hole 532 of the rotating side seal disk 50B, leaving a predetermined thickness from the inner peripheral surface of the inner peripheral surface 31 and forming a lip shape. Have been. The inner diameter of the lip portion, that is, the seal portion 531B, is slightly smaller than the outer diameter of the plunger 55. For example, the inner diameter of the seal portion 531B is formed to have a size in a range of −0.01 to −0.50 mm with respect to the outer diameter of the plunger 55. Further, since the pump block body 50A is made of elastic cross-linked PTFE, the seal portion 531B also has elasticity. Such a seal portion 531B is formed at a position slightly above the tip of the plunger 55 when the plunger 55 is at the upper end position of the stroke. Therefore, the plunger 5
As long as 5 moves within the stroke range, the seal portion 5
31B always contacts and seals the plunger 55.

A plunger 55 is inserted into the plunger insertion hole 53, and a coil spring 56 as urging means is interposed between the plunger 55 and the pump block 50. The plunger 55 is formed by the coil spring 56.
Is constantly in contact with the large diameter portion 61 of the pump drive shaft 60, the pump block 50 is urged toward the valve block 35, and the sliding surface 38 of the valve block 35 and the sliding surface 51 of the pump block 50 It comes into sliding contact with a predetermined pressure. The diameter of the portion of the plunger 55 inserted into the plunger insertion hole 53 can be set as appropriate. For example, in the case of the thinnest, about 0.3 to 0.8
It can be as thin as about mm. On the other hand, if the thickness is to be increased, there is no particular limitation and the setting may be made according to the discharge amount. However, since the dispenser 1 of the present embodiment is particularly suitable for discharging a very small amount, the upper limit is usually about 5 mm. Good. Further, the coil spring 56 constantly urges the pump drive shaft 60 upward through the plunger 55, so that the roller 6
5 is always in contact with the roller guide 24 of the guide member 20.

Next, the operation of this embodiment will be described with reference to FIGS.
This will be described with reference to FIG. 11A and FIG.
1 (B), FIG. 12 (C), and FIG. 12 (D), the left-hand drawing is a cross-sectional view of the guide member 20 from the top,
Sectional view of pump block 50 and valve block 35, upper surface of valve block 35 and plunger insertion hole 5
3 is a schematic diagram showing the positional relationship with the pump 3 and the right-hand side is a cross-sectional view in the side direction (a position different by 90 degrees) from the left-side cross-sectional view of the pump block 50 and the valve block 35.

First, the container 90 containing the liquid 7 is attached to the container connecting member 91. The ejection amount is set in advance by operating the micrometer 80 to incline the guide member 20. In the present embodiment, the discharge amount changes in proportion to the stroke amount of the plunger 55. This stroke amount is equal to the vertical movement amount of the roller 65, that is, the guide member 20.
Of the roller guide 24 from the lower end position to the upper end position. The height dimension of the vertical position of the roller guide 24 is proportional to the inclination angle of the guide member 20, and the inclination angle is set by the position of the contact member 82, that is, the position of the spindle 81 of the micrometer 80. Therefore, if the discharge amount per scale of the micrometer 80 is measured in advance, a scale corresponding to a desired discharge amount can be calculated. Therefore, only by operating the micrometer 80 and adjusting the scale, the discharge can be performed. The amount can be adjusted.

In this embodiment, the state shown in FIG. 11A is set as the origin. In the home position, the plunger insertion hole 53 communicates with the suction opening 43. The plunger 55 is located at an intermediate position where the plunger 55 moves from a lower stroke end (a position where the roller 65 is closest to the fixed shaft 21 of the guide member 20) to an upper stroke end (a position where the roller 65 is closest to the contact shaft 25). (The middle position of the vertical stroke end).

In this home position, when a start signal is input by pressing a start button or the like, the motor 1
1 is operated, and the rotation interlocking member 12 is rotated. The rotation of the rotation interlocking member 12 is transmitted to the pump block 50 via the rotation transmission member 15, the pump drive shaft 60, and the rotation transmission rod 62, and the pump block 50 is rotated while being in sliding contact with the valve block 35. . With this rotation, the plunger 55 gradually rises, and the liquid 7 is sucked from the suction port 42 into the plunger insertion hole 53 until the plunger insertion hole 53 comes off the suction opening 43.

At this time, the inner diameter of the seal portion 531B is slightly smaller than the outer shape of the plunger 55 and is formed in a lip shape. The plunger 55 comes into contact with the plunger 55 by force, and seals between the plunger 55 and the plunger insertion hole 531.

Then, as shown in FIG. 11B, when the plunger 55 moves to the upper stroke end position, the plunger insertion hole 53 is at an intermediate position where it moves from the suction opening 43 to the discharge opening 40. The liquid 7 sucked into the plunger insertion hole 53 is also separated from other liquids.

Further, when the rotation by the motor 11 continues and the plunger 55 moves from the upper stroke end to the intermediate position of the lower stroke end as shown in FIG. The plunger 55 moves to the communicating position, and continues to move downward. And, with this movement, the plunger insertion hole 53
The liquid 7 inside is discharged from the discharge needle 46 via the discharge port 41.

The discharge of the liquid 7 is performed by the discharge opening 40.
After a part of the plunger insertion hole 53 starts communicating with the
It continues until it comes off the discharge opening 40, that is, from before the state of FIG.

When the liquid 7 is ejected, the pressure of the liquid 7 increases because the liquid 7 is pushed out. This liquid 7
Is also flowing into the groove 531C around the seal portion 531B, and the seal portion 531B is pressed against the plunger 55 by the pressure of the liquid 7 in the groove 531C. For this reason, the contact force of the seal portion 531B is increased and the sealing performance is improved, so that even if the pressure of the liquid 7 increases, the sealing can be reliably performed.

When the pump block 50 continues to rotate and the plunger insertion hole 53 comes off the discharge opening 40, the discharge of the liquid 7 is stopped. Then, FIG.
As shown in (D), when the plunger 55 moves to the position of the lower stroke end, the plunger insertion hole 53 moves to the intermediate position between the discharge opening 40 and the suction opening 43, and completely closes with these openings 43, 40. Will be in a state of isolation.

Further, when the pump block 50 continues to rotate, the plunger 55 rises, and from the time when the plunger insertion hole 53 communicates with the suction opening 43, the liquid 7 is sucked into the plunger insertion hole 53 as the plunger 55 rises. Is done. Then, when returning to the state of FIG. 11A, the rotation position is detected by the rotation position detection sensor 17, and the motor 11 is stopped. Hereinafter, a predetermined amount of the liquid 7 is sequentially discharged by repeating the above operations. It should be noted that the operation continues from FIG. 11 (A) to FIG. 11 (B), FIG. 12 (C) and FIG. 12 (D) until returning to FIG. 11 (A), that is, until the motor 11 makes one rotation. , FIG.
There is no stop in each state of (B), FIG. 12 (C), and FIG. 12 (D).

When the discharge of the liquid 7 is stopped and the suction of the liquid is started, the pressure of the liquid 7 is also reduced.
The contact force of the 1B against the plunger 55 also decreases, and the sealing portion 5
The plunger 55 comes into contact with the elastic force of 31B. That is, the seal portion 531B functions as a self-sealing.

As described above, in this embodiment, the pump drive shaft 60 can be controlled by the motor 11 and the rotation position detection sensor 17 every one rotation. For this reason, in this embodiment, the motor 11, the rotation interlocking member 12, and the rotation position detection sensor 17 constitute a rotation drive unit that drives the pump drive shaft to rotate in units of one rotation. Further, the guide member 20, a roller 65 as a driven portion, and a coil spring 56 for bringing the roller 65 into contact with the roller guide 24 of the guide member 20 constitute an advance / retreat driving unit.

According to the present embodiment, the following effects can be obtained. (1) Since the seal portion 531B is formed integrally with the pump block 50 in which the plunger insertion hole 53 is formed, the entire pump block 50 can be handled as compared with the case where a separate small sealing material is used as in the related art. Since the number of parts can be reduced, handling can be facilitated and assembling workability can be improved.

(2) Since the seal portion 531B is formed integrally with the pump block 50, no error occurs due to the change of the discharge amount due to the movement of the seal material. Discharge can be performed with high accuracy. Furthermore, since there is no liquid leakage from the seal portion 531B, the liquid 7 can be discharged with high precision in proportion to the amount of movement of the plunger 55. Furthermore, unlike the case where a separate sealing material is used, there is no misalignment between the seal portion 531B and the plunger insertion hole 53, so that the plunger 55 does not tilt and stroke, and only a part of the seal portion 531B is biased. Wear can also be prevented. Therefore, the life of the pump block main body 50A can be extended, and the seal portion 531 can be provided.
Even if B is formed integrally with the pump block main body 50A, the frequency of replacement can be reduced.

(3) Further, since there is no need to handle the seal alone and to form the seal arrangement groove, the size of the pump block 50 can be minimized. Therefore, the driving mechanism such as the motor 11 for driving the pump block 50 can be downsized, the size of the dispenser (liquid ejection device) 1 can be reduced, and the manufacturing cost can be reduced.

(4) Since the size of the pump block 50 can be reduced, the pump block 50 and the valve block 3
5 can be reduced in contact area. For this reason, if the force of the coil spring 56 pressing the pump block 50 against the valve block 35 is the same as the conventional one, the discharge pressure can be increased. If the discharge pressure is the same, the coil spring 56 pressing the pump block 50 against the valve block 35 can be used. Power can be changed to a smaller one.

(5) The seal portion 531B is formed in a lip shape, a groove 531C communicating with the plunger insertion hole 53 is formed on the outer peripheral side of the lip portion, and the pump block main body 50A including the seal portion 531B has elasticity. Since it is made of a material, the seal portion 531B can be brought into contact with the plunger 55 with an appropriate elastic force. Besides, the groove 5
Since 31C communicates with the opening of the plunger insertion hole 53 on the valve block side, when the pressure of the liquid 7 is high, such as at the time of discharging the liquid, the pressure of the liquid 7 in the groove 531C is also used to make the seal portion 531B more tight. The plunger 55 can be urged with a large force. Therefore, when the pressure of the liquid 7 in the plunger insertion hole 53 increases and the sealing performance needs to be improved, the plunger 55 of the sealing portion 531B is required.
The contact performance with the seal can be increased to improve the sealing performance. On the other hand, if the pressure of the liquid 7 is not so high,
By suppressing the contact force (seal performance) of the 1B against the plunger 55, the frictional force can be reduced, and the occurrence of wear of the seal portion 531B can be suppressed. Therefore, the sealing portion 531B
Can ensure the required sealing performance and can prolong the service life.

(6) Since the pump block main body 50A, that is, the seal portion 531B is made of a crosslinked PTFE, it has excellent chemical resistance and can be used for discharging various liquids. In addition, since the friction coefficient is small and the abrasion resistance is excellent, the life can be extended.

(7) A flat valve plunger pump that rotates with the pump block 50 slidably contacting the valve block 35 and switches between the discharge opening 40 and the suction opening 43 formed in the sliding contact surface 38. Since the method is adopted, the plunger 55 only needs to move in the plunger insertion hole 53. Therefore, unlike the D-cut plunger pump, there is no need to perform switching by its own rotation,
The diameter of the plunger 55 can be made very small. For this reason,
The discharge amount of the liquid 7 set by the diameter of the plunger 55 and its stroke can be made extremely small, and a very small amount of liquid such as several microliters or several nanoliters can be easily discharged.

(8) Further, since only one plunger 55, that is, only one plunger insertion hole 53, is formed, a plane in which the plunger insertion hole 53 and the respective openings 40, 43 are not formed in the respective sliding contact surfaces 38, 51. A large area of the portion can be secured. For this reason, the sealing performance can be improved by the sliding surfaces 38 and 51 slidingly contacting each other.
3 and the discharge opening 40 can be reliably sealed. In addition, since the area of the flat portion is large, the plunger insertion hole 53 can be reliably separated from the openings 40 and 43 while the plunger insertion hole 53 is moved from the suction opening 43 to the discharge opening 40, and the discharge accuracy can be improved. . Furthermore, since only one plunger insertion hole 53 and one plunger 55 are provided, the pump drive shaft 60, that is, the pump block 5
Since one ejection operation is performed by one rotation of 0, 1
The same discharge operation is performed each time, and the accuracy of the discharge amount each time can be improved.

(9) Since the sliding surface 38 is coated with the diamond-like carbon film, the sliding surfaces 38, 5
(1) The sealing performance and slidability can be improved, and the performance of the flat valve can be greatly improved.

(10) Since the valve block 35, the pump block 50, etc., which are in contact with the liquid 7 of the pump section 3, are made of a material having excellent chemical resistance such as stainless steel, ceramics, fluororesin, etc. 7 can be handled. Further, since the pump unit 3 and the drive unit 2 are separated, stainless steel or ceramics having a high unit price can be used only for the pump unit 3, and even the chemical-resistant dispenser 1 can be provided at a low price. it can.

(11) Since the container 90 is separate from the dispenser 1, the container 90 can be easily replaced, and an expensive liquid 7 sold in a container can be easily handled.

Next, a liquid ejection apparatus 100 according to a second embodiment of the present invention will be described with reference to FIGS. The liquid ejection device 100 of the present embodiment mainly includes three plungers 1
45 is provided so that the discharge of the liquid by the three plungers 145 is performed sequentially and continuously, so that the pump can be used as a pump capable of continuously discharging a fixed amount of liquid. This is different from the first embodiment.

As shown in FIG. 13, the liquid discharging apparatus 100 includes a body 110, and the body 110 is
11, a cap 112 bolted to one end of the main cylinder 111, and a connection cylinder 114 bolted to the other end of the main cylinder 111 via a cam 113.

As shown in FIG. 14, the cap 112 has a peephole 112B, and a cylindrical cover member 190 made of a transparent resin or the like is fitted on the inner peripheral surface thereof. Further, the cap 112 is also provided with a drain port 119 used for discharging leaked liquid and cleaning the inside of the pump.

As shown in FIGS. 14 and 15, a substantially disk-shaped valve block 120 is attached to the cap 112. The valve block 120 has a suction port 121 and a discharge port 122 in which female threads are formed. A container containing a liquid to be discharged, a nozzle for discharging, and the like are appropriately screwed into these ports 121 and 122.

Each of the ports 121 and 122 is opened on the sliding surface 138 of the valve block 120. As in the first embodiment, the valve block 120 is made of stainless steel, and the sliding contact surface 138 is coated with a diamond-like carbon film (DLC), and is configured to also function as a fixed-side seal disk. I have.

The sliding contact surface 1 of each of the ports 121 and 122
As shown in FIGS. 16 and 17, the openings 38 are arc-shaped grooves 134 and 135, respectively.

In the cap 112, a substantially cylindrical pump block 140 is rotatably disposed adjacent to the valve block 120. This pump block 140
The pump block main body 1 is similar to the first embodiment.
40A, and a rotation-side seal disk 140B that is prevented from rotating by a pin 140C with respect to the main body 140A.

At the lower end of the pump block 140 (the lower surface of the rotary seal disk 140B), a sliding contact surface 141 that slides on the sliding contact surface 138 is formed. Also in this embodiment, the pump block main body 140A is made of a crosslinked fluororesin (crosslinked PTFE), and the rotary seal disk 140B is made of a super engineering plastic such as polyamideimide or ceramic.

The pump block 140 has a plurality of, for example, three plunger insertion holes 142 formed therethrough. Each plunger insertion hole 142 is also provided with a plunger insertion hole 241 formed through the pump block main body 140A, similarly to the above-described embodiment.
And a plunger insertion hole 242 formed through the rotation side seal disk 140B and having a diameter larger than the plunger insertion hole 241.

The sliding surface 141 of each plunger insertion hole 142
Side opening is provided with two grooves 13 of the valve block 120.
4, 135, and the plunger insertion hole 142 and the grooves 134, 135 are formed when the plunger 145 inserted into each plunger insertion hole 142 is performing a suction or discharge operation. When the plunger 145 is sliding in the axial direction, the grooves 134, 1
35, and have such a size and position that the suction or discharge operation is not performed when the plunger insertion hole 142 is separated from the grooves 134 and 135.

The plunger insertion hole 241 is provided in the plunger 1 inserted in the hole 241 as in the first embodiment.
A guide portion 241A for guiding the plunger 45;
5 and a seal portion 241B for sealing between the plunger insertion hole 241. That is, the guide portion 241A has an inner diameter (plunger 14) capable of guiding the plunger 145 smoothly and without rattling.
(+0.02 to 0.10 mm with respect to the outer diameter of No. 5). Further, the seal portion 241B has a predetermined thickness from the inner peripheral surface of the plunger insertion hole 241 and the opening of the plunger insertion hole 241 on the valve block 120 side, that is, the plunger insertion hole 24 of the rotation side seal disk 140B.
2 is formed in a lip shape by forming a groove 241C communicating with the second groove 241C.

The lip portion, that is, the seal portion 2
41B has an inner diameter slightly smaller than the outer diameter of the plunger 145 (for example, −0.0 to the outer diameter of the plunger 145).
01 to -0.50 mm). Also, a cross-linked PTF in which the pump block body 140A has elasticity
Because it is made of E, the seal portion 241B is also made of an elastic material. This seal portion 241B is also used for the plunger 1
45 is formed at a position slightly above the tip of the plunger 145 when it is at the upper end position of the stroke.

The pump block 1 is provided in the cap 112.
A spring guide block 150 is arranged adjacent to 40. A disc spring 151 is interposed between the spring guide block 150 and the rotating body 161 disposed in the main cylinder 111.

The pump block 140 and the spring guide block 150 are provided with three pins 1 in holes formed at regular intervals of 120 degrees on the respective contact surfaces of the blocks 140 and 150.
By inserting 40C, it is possible to rotate integrally.

Plunger 1 of spring guide block 150
In the spring guide hole 153 in which the spring 45 is disposed, a substantially cylindrical spring receiver 1 through which a plunger 145 is penetrated so as to advance and retreat.
54 are arranged. A pressing spring 156 as an urging member formed of a compression coil spring is interposed between the spring receiver 154 and the spring receiver 155 fitted to the right end side of the plunger 145 in the drawing. The pressing spring 156 urges the plunger 145 in the suction direction, that is, in the direction away from the pump block 140.

Therefore, the pump block 140 is urged toward the valve block 120 through the spring guide block 150 by the urging force of the pressing spring 156 and the disc spring 151, and the sliding contact surface 138 of the valve block 120 and the pump block The sliding contact surface 141 of the sliding contact 140 is brought into sliding contact with a predetermined pressure. The pressing spring 156 and the disc spring 151 constitute an urging means. In the case where it is not necessary to increase the urging force so much as in the case of a low-viscosity liquid or the like, the valve block 120 and the pump block 140 are slid by the urging force of only the pressing spring 156 without providing the disc spring 151. Is also good.

The plunger 145 has a retaining ring 158
Are fitted, and the plunger 145 is connected to the spring guide block 1.
When the spring ring 154 is removed from the locking ring 15,
8 so as not to come off.

At one end of the spring guide block 150, that is, at the right end in FIG. 14, a rotating body 161 is rotatably disposed in the main cylinder 111 and the cam 113 via bearings 117 and 118. Three connecting pins 162 are projected from the end face of the rotating body 161 on the guide block 150 side at equal intervals of 120 degrees, and these connecting pins 162 are provided.
Is inserted into a connection hole 157 opened at the end face of the block 150, and the rotation of the rotating body 161 is transmitted to the block 150.

The right end side of the rotating body 161 in the figure is fixed to an output shaft 166 of a motor 165 via a coupling 167 composed of an Oldham coupling or the like. Here, the motor 165, the coupling 167, the rotating body 16
1. Spring guide block 150 and connecting pins 140
The rotation driving means 160 of the pump block 140 is constituted by C and 162, and the rotation of the motor 165 is smoothly transmitted to the pump block 140.

Inside the rotating body 161, three rods 181 which are arranged at equally spaced positions at 120 degrees are opposed to the three plungers 145 inserted into the plunger insertion holes 142 of the pump block 140. 182 are inserted slidably in the axial direction. In the middle of this rod 181, a concave portion 161 formed in the middle of the rotating body 161 is provided.
In B, the follower holder 183 is pinned.

The shaft 183 of each follower holder 183
A cam follower 184 including two rollers is rotatably attached to B. Each of these cam followers 18
Numeral 4 is guided in an axial follower guide hole 161C formed at a 120-degree equidistant position on the peripheral surface of the rotating body 161 so as to be movable in the axial direction but not in the rotational direction.

The cam follower 184 is connected to the cam 1
13 is pressed against the cam surface 113A formed on the end face of the thrust member 13 by the pressing force of the pressing spring 156, and advances and retreats in the axial direction along the shape of the cam surface 113A with the rotation of the rotating body 161. The force is transmitted to the rod 181 via the follower holder 183, and further, the plunger 1
Here, the rod 181, the follower holder 183, the cam follower 184
The cam surface 113A of the cam 113 constitutes a plunger advance / retreat driving means 180.

Next, the operation of the present embodiment will be described. First, a liquid tank to be transferred via a tube or the like is connected to the suction port 121, and the discharge port 1 is connected.
A transfer destination container is also connected to 22 via a tube or the like. Also, a liquid recovery tank is connected to the drain port 119 via a tube or the like.

In this state, when the motor 165 of the rotation driving means 160 is driven, the rotation of the output shaft 166 is rotated by the pump via the rotation driving means 160 including the coupling 167, the rotating body 161, the spring guide block 150 and the like. It is transmitted to the block 140 and rotates the pump block 140 in sliding contact with the valve block 120.

With this rotation, the rod 181 interposed in the rotating body 161 rotates together with the rotating body 161, so that the cam follower 184 supported by the rod 181 via the follower holder 183 acts on the action of the pressing spring 156. Accordingly, the cam surface 113A advances and retreats along the axial displacement of the cam surface 113A while being in contact with the cam surface 113A. At this time, the cam follower 184 is connected to the follower guide hole 16 of the rotating body 161.
Since the rod 181 is guided to move only in the axial direction by 1C, the rod 181 smoothly advances and retreats along the axial displacement of the cam surface 113A.

The advance / retreat of the rod 181 is transmitted to the plunger 145 via the spring receiver 155 or the like, and the plunger 14
5 is a plunger insertion hole 142 of the pump block 140.
In the axial direction within. The plunger 145 can be advanced or retracted by setting the shape of the cam surface 113A to an appropriate shape so that the plunger 145 faces away from the suction port 121 at a position facing the suction port 121,
That is, it is moved rightward in FIG. The rightward movement of the plunger 145 causes the plunger insertion hole 142 to move.
A negative pressure is generated in a space formed on the left end side of the liquid, and the liquid to be transferred is sucked through the suction port 121 and the groove 134 by the negative pressure.

At the point where the movement of the plunger 145 to the right is completed, the plunger insertion hole 142 deviates from the position of the groove 134 connected to the suction port 121 and moves toward the groove 135 of the discharge port 122. It will be. During this movement, since the cam surface 113A has a flat shape with no axial displacement, the plunger 145 does not advance or retreat in the axial direction, and moves toward the groove 135 while maintaining the same position. Moving.

When the plunger insertion hole 142 is
When it comes to a position communicating with the groove 135 on the second side, the cam surface 113
By the action of A, the cam follower 184 of the plunger advance / retreat driving means 180 is moved leftward in the figure, and with the movement of the cam follower 184, the plunger 145 is also moved leftward via the rod 181 and the like, and Into the plunger insertion hole 142 at the left end face of the plunger 145.
It is extruded from the inside, and the discharge port 122 is
Discharge into the interior.

The discharge operation of the liquid by the plunger 145 is performed while the plunger insertion hole 142 communicates with the arc-shaped groove 135, and is completed before the plunger insertion hole 142 comes off from the groove 135. Hole 14
2 comes out of the groove 135, the plunger 14
The axial movement of No. 5 is stopped. This plunger 145
Is held until the plunger insertion hole 142 returns to the position of the groove 134 on the suction port 121 side by the action of the cam surface 113A.

Thus, the plunger insertion hole 142
Is moved to the groove 134 side of the suction port 121 again, the plunger 145 is moved rightward again by the action of the cam surface 113A, and moves to the suction operation of sucking the liquid from the suction port 121, and so on. Is repeated, and one rotation of the pump block 140 of one plunger insertion hole 142 is performed by each rotation, so that the liquid suction and discharge operations are performed one cycle at a time.

The suction and discharge operations accompanying the advance and retreat of the plunger 145 are similarly performed for each plunger insertion hole 142.
As can be seen from FIGS. 16 and 17, the two adjacent plunger insertion holes 142 can communicate with the grooves 134 and 135 at the same time during the suction or discharge operation. The liquid sucked into or discharged from the plunger insertion hole 142 is continuously sucked or discharged to maintain a constant flow rate. In addition, by appropriately setting the shape of the cam surface 113A, each plunger insertion hole 1
Since the total flow rate of the liquid sucked or discharged into the nozzle 42 is always constant, suction and discharge without pulsation can be performed.

In the operation of the liquid discharging apparatus 100, the pump block 140 is driven by the spring guide block 1 by the disc spring 151 and the pressing spring 156 as urging means.
The slidable contact surface 138 and the slidable contact surface 141 are urged by a predetermined contact pressure through the valve block 120 toward the valve block 120 side, and the seal is necessary and sufficient.

As in the first embodiment, when the pressure of the liquid in the plunger insertion hole 142 increases and the sealing performance needs to be improved, the sealing portion 241B is used.
The sealing performance can be improved by increasing the contact force with the plunger 55. On the other hand, when the pressure of the liquid is not so high, the contact force (seal performance) of the seal portion 241B to the plunger 55 can be suppressed, and the frictional force can be reduced.
41B can be suppressed from occurring. Therefore, the seal portion 241B can reliably secure necessary sealing performance and can achieve a long life.

In this embodiment, the same operation and effects as (1) to (7) and (9) to (11) of the first embodiment can be obtained. (12) Since three plunger insertion holes 142 are provided, each plunger insertion hole 142 can communicate with the suction port 121 and the discharge port 122 so that liquid suction and discharge can be performed at the same time. Can be shortened.

(13) Also, arc-shaped grooves 134 and 135 are formed in the openings of the ports 121 and 122, and when one plunger insertion hole 142 starts to come off from each of the grooves 134 and 135, the next plunger insertion hole is formed. 142 is the groove 134, 13
Since it is located at five portions, at least one plunger insertion hole 142 can be always located in each of the grooves 134 and 135. Thus, continuous suction and continuous discharge of liquid can be performed, continuous liquid discharge without pulsation can be performed, and the device can be used as a pump.

(14) The plunger 145 is moved forward and backward by the rod 1
Since it is uniquely set according to the shape of the cam surface 113A of the cam 113 via 81, the movement of the plunger 145 can be accurately controlled by appropriately setting the shape of the cam surface 113A, and there is no pulsation at this point as well. Accurate ejection can be performed.

Note that the present invention is not limited to the configuration of each of the above embodiments, and modifications within a range that can achieve the object of the present invention are included in the present invention.

For example, the pump block bodies 50A, 14
The material of 0A is not limited to a cross-linked fluororesin such as PTFE, but may be various engineering plastics or rubbers. In other words, if the seal portions 241B and 531B have elasticity, it depends on the type of the liquid 7 to be discharged. May be selected appropriately. Also, the rotating side seal disk 50
B, 140B, and the material of the valve blocks 35, 120, which are the fixed-side seal disks, may also be appropriately set in implementation.

Further, the construction of the pump blocks 50, 140 is the same as in the above embodiments, with the pump block main bodies 50A, 140A and the rotating side seal disk 50 being different from each other.
B and 140B are not limited to two members, and may be formed integrally. In this case, for example, the lower side of the seal portions 531B, 241B in which the grooves 531C, 241C of the plunger insertion holes 53, 142 are formed (on the valve block 35, 120 side; ) Is tapered so that the inner diameter gradually increases from the large diameter or the lower end opening, and the upper side (the guide parts 531A, 24) of the seal parts 531B, 241B.
1A) to a diameter substantially the same as the plunger 55,
What is necessary is just to constitute the pump block which has a lip-shaped seal part and a guide part. However, when two members are used as in the above-described embodiment, processing of the grooves 531C and 241C is particularly easy.

Further, the seal portions 241B and 531B are not limited to those having a self-sealing structure formed in a lip shape as in the above embodiments. For example, as shown in FIG. 18, the pump block 250 is integrated (two bodies are also possible).
And an intermediate portion of the plunger insertion hole 53 penetrating the pump block 250 (the plunger 55 is
Above the lower end of the plunger 55 at the end of the upper end stroke that is away from the other guide portion 53.
A convex portion having an inner diameter smaller than 1A may be formed as the seal portion 531B.

However, the lip shape as in the above embodiment can reduce the spring constant of the seal portion and increase the displacement of the seal portion as compared with the convex seal portion 531B. (The difference between the outer diameter of the plunger and the inner diameter of the seal portion) can be increased. For example, in the case of a lip-shaped seal portion, the inner diameter of the seal portion can be about -0.05 to -0.50 mm with respect to the outer diameter of the plunger.
-0.01 for a convex seal with a large spring constant
It needs to be reduced to about -0.05 mm. For this reason, when the seal portion is worn by the movement of the plunger 55,
If the protrusion size is small, the service life until the seal part fails due to wear is short, but the protrusion size is large,
The lip-shaped seal portion, which can deform and seal the seal portion, can prolong the life of the lip-shaped seal portion even if it is worn, because the protrusion size is large.

Further, in the first embodiment in which only one plunger 55 is provided, the configuration of the seal portion is as follows.
What used the pressing means as shown in FIG. 19 may be used. That is, in the modified example of FIG.
The plunger insertion hole 532 of 0B has a small diameter portion 532A having an inner diameter larger than the diameter of the plunger 55, and a small diameter portion 532.
A large diameter portion 532B having a larger inner diameter than A.

The large diameter portion 532B protrudes from the end face of the pump block main body 50A and has a plunger insertion hole 53.
A seal portion 531B arranged in a ring shape is inserted around the periphery of 1. An O-ring 540, which is a pressing means made of rubber or the like, is provided between the large diameter portion 532B and the seal portion 531B, that is, between the inner peripheral surface of the large diameter portion 532B and the outer peripheral surface of the seal portion 531B. Is equipped.

With such a configuration, the same functions and effects as (1) to (4) and (6) to (11) of the first embodiment can be obtained. (15) In addition, the elastic force of the O-ring 540 makes the plunger 5
Since the seal portion 531B can be brought into contact with the outer peripheral surface of 5, the contact pressure of the seal portion 531B with the plunger 55 can be easily controlled within an appropriate range. For this reason, the seal portion 531B can reliably secure necessary sealing performance and can achieve a longer life.

(16) The sealing portion 5 is formed by the O-ring 540.
Since 31B is in contact with the plunger 55, the seal itself, that is, the pump block body 50A does not need to be formed of an elastic material as in the above embodiments. For this reason,
The pump block body 50 is made of a material having no elasticity, for example, a tetrafluoroethylene copolymer (trade name: Teflon) to which a general filler such as carbon or glass fiber is added.
A can be manufactured and the restrictions on the materials used are reduced.
The pump block 50 can be manufactured from an appropriate material in consideration of other characteristics, cost, and the like.

(17) Further, since the seal portion 531B is brought into contact with the plunger 55 by the elastic force of the O-ring 540, the accuracy of the inner diameter of the seal portion 531B is not so required, and the seal portion 531B can be easily manufactured. .

(18) In addition, the pump block body 50A and the rotating side seal disk 5 are
Since the contact surface 0B can also be sealed, it is possible to prevent the discharge liquid from leaking from the contact surface portion of the pump block main body 50A and the rotating side seal disk 50B to the outer peripheral side. For this reason, it is not necessary to arrange a sealing material separately, and the cost can be reduced.

(19) Further, the O-ring 540 is
Since it is interposed between 32B and the seal portion 531B, the dead space such as the self-sealing groove 531C can be reduced, and the inflow and stagnation of the liquid to be discharged can be reduced. Therefore, even a liquid such as an adhesive that solidifies when staying therein can be discharged, and various kinds of liquids can be discharged.

Incidentally, as shown in FIG. 20, the sealing structure using such an O-ring 540 uses the pump block 14 of the second embodiment using three plungers 145.
It may be applied to 0. That is, the pump block 140
19, the plunger insertion hole 242 of the rotary seal disk 140B is composed of a small-diameter portion 242A and a large-diameter portion 242B as in FIG. 19, and the seal portion 241B of the pump block 140A is inserted and arranged in the large-diameter portion 242B. The O-ring 540 may be disposed between the seal part 241B and the large diameter part 242B. Also in this case, the operation and effect of the second embodiment and the operation and effects similar to the above (15) to (19) can be obtained.

In the example shown in FIGS. 19 and 20, the seal portion 2
41B and 531B are guide parts 241A and 531 respectively.
21A, the inner diameter of the seal portion 531B is smaller than that of the guide portion 531A, as shown in FIG.
Or the guide portion 531A
May be made larger than the inner diameter of. Also in this case, the O-ring 540 is interposed between the large diameter portion 532B and the seal portion 531B, so that the seal portion 531B is curved as shown in FIG. Can be.

In this case, the same operation and effect as those of the seal portion of FIGS.
Since the inner diameter of 1B can be aligned with the guide portion 531A, it can be easily processed and the manufacturing cost can be reduced.

Further, an O-ring 540 is used as the pressing means.
The present invention is not limited to this, and various elastic members such as coil springs and members having no elastic force such as spacers may be used. Further, the pressing means is not limited to the one separate from the pump block main body 50A and the rotating side seal disk 50B. For example, when protrusions are formed at predetermined intervals on the inner peripheral surface of the large-diameter portion 532B of the rotating-side seal disk 50B and the sealing portion 531B is inserted into the large-diameter portion 532B, the rotating-side seal disk 50B
Of the plunger 55
May be configured to abut.

In short, according to the present invention, the sealing portion 2
41B and 531B need only be formed integrally with the pump block, and the specific structure and the like may be appropriately set for implementation. Also, the guide parts 241A, 531
A, grooves 241C, 531C, plunger insertion holes 242,
The specific size and shape of 532 are not limited to the above-described embodiments, and may be appropriately set in implementation.

The number of plungers 55 and 145 is not limited to one or three, but may be two or four or more.
Also, the plungers 55 and 145 and the valve block 35,
The drive mechanism 120 is not limited to the configuration of the above-described embodiment. For example, the forward / backward drive of the plungers 55 and 145 and the rotational drive of the valve blocks 35 and 120 may be realized by independent drive mechanisms. do it.

[0127]

According to the liquid ejecting apparatus of the present invention, a very small amount of liquid can be ejected with high accuracy, handling is easy, and uneven wear of the seal can be eliminated. Miniaturization can also be realized.

[Brief description of the drawings]

FIG. 1 is a front view showing a dispenser which is a liquid ejection device according to a first embodiment of the present invention.

FIG. 2 is a longitudinal sectional view showing a driving unit of the embodiment.

FIG. 3 is a longitudinal sectional view showing a pump section of the embodiment.

FIG. 4 is a sectional view of a main part taken along line IV-IV in FIG. 2;

FIG. 5 is a sectional view taken along line VV in FIG.
It is sectional drawing along the line.

FIG. 6 is a perspective view showing a guide member of the embodiment.

FIG. 7 is a sectional view taken along the line VII-VII in FIG. 3;

FIG. 8 is a perspective view showing a main part of a pump section of the embodiment.

FIG. 9 is a sectional view taken along line IX-IX in FIG. 3;

FIG. 10 is a bottom view of the pump section of the embodiment.

FIG. 11 is an explanatory diagram showing an operation of the pump section of the embodiment.

FIG. 12 is an explanatory diagram showing a continuation of the operation in FIG. 11;

FIG. 13 is a front view illustrating a liquid ejection apparatus according to a second embodiment of the present invention.

FIG. 14 is a sectional view showing a main part of the second embodiment.

FIG. 15 is an enlarged sectional view of a main part of the second embodiment.

FIG. 16 is a sectional view taken along the line AA of FIG. 14;

FIG. 17 is a schematic perspective view showing a valve block according to a second embodiment.

FIG. 18 is a sectional view showing a main part of a modification of the present invention.

FIG. 19 is a cross-sectional view showing a main part of another modification of the present invention.

FIG. 20 is a cross-sectional view showing a main part of another modification of the present invention.

FIG. 21 is a sectional view showing a main part of another modification of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Dispenser which is a liquid discharger 2 Drive part 3 Pump part 7 Liquid 10 Body 11 Motor 20 Guide member 30 Case 35 Valve block 38, 51 Sliding contact surface 41 Discharge port 42 Suction port 45 Discharge nozzle 50 Pump block 50A Pump block main body 50B Rotation side seal disk 50C Pin 53 Plunger insertion hole 55 Plunger 60 Pump drive shaft 62 Rotation transmission rod 80 Micrometer 90 Container 100 Liquid discharge device 110 Body 120 Valve block 121 Suction port 122 Discharge port 134, 135 Arc-shaped groove 138, 141 Sliding contact surface 140 Pump block 140A Pump block main body 140B Rotating side seal disk 140C Pin 142 Plunger insertion hole 145 Plunger 150 Spring guide blow Hook 160 Rotation drive means 165 Motor 180 Plunger advance / retreat drive means 181 Rod 241, 242 Plunger insertion hole 241A Guide part 241B Seal part 241C Groove 242A, 532A Small diameter part 242B, 532B Large diameter part 531 532 Plunger insertion hole 531B Seal part 531C Groove

Claims (6)

[Claims] 1. A valve block having a sliding contact surface, a pump block having a sliding contact surface capable of abutting on the sliding contact surface of the valve block, and at least one pump drilled along the axial direction of the pump block. A plunger inserted in the plunger insertion hole so as to be slidable in the axial direction, an urging means for urging the pump block toward the valve block, a rotation driving means for rotating the pump block, and a shaft A plunger advancing / retreating drive means for advancing and retreating in a direction, wherein the valve block has a discharge port communicating with a discharge opening formed in the sliding contact surface and a discharge port opened on a liquid discharge side, A suction port communicating with a suction opening formed in the sliding contact surface and a supply port opened on the liquid supply side; and a plunger insertion hole of the pump block, The pump block is provided with a seal portion formed in the pump block at a position communicable with the discharge opening and the suction opening of the block block along the axial direction, and sealing between the plunger and the plunger insertion hole. Liquid ejecting device. 2. The liquid ejecting apparatus according to claim 1, wherein the seal portion leaves a predetermined thickness from an inner peripheral surface of the plunger insertion hole and communicates with an opening of the plunger insertion hole on the valve block side. The liquid ejecting apparatus is formed in the shape of a lip by forming a lip, and the inner diameter of the lip portion is made smaller than the outer diameter of the plunger, and is made of a material having elasticity. 3. An apparatus according to claim 1, wherein said plunger has an outer diameter of 0.3 to 5 mm.
The inner diameter of the plunger insertion hole is +0.01 to +0.10 mm with respect to the set outer diameter of the plunger.
The inner diameter of the seal portion is in the range of -0.01 to -0.50 mm with respect to the set outer diameter of the plunger, and the absolute value thereof is larger than the gap between the plunger insertion hole and the plunger. A liquid ejection device characterized by being set to: 4. The liquid discharging apparatus according to claim 1, wherein the pump block is made of a cross-linked fluororesin or polyamideimide. 5. The liquid ejecting apparatus according to claim 1, wherein the seal portion is arranged in a ring shape around the plunger insertion hole, and is pressed by pressing means to abut on the outer peripheral surface of the plunger. A liquid discharge device, which is in contact with the liquid discharge device. 6. The liquid discharging apparatus according to claim 5, wherein the pump block includes a pump block main body, and a rotation-side seal disk that is prevented from rotating with respect to the pump block main body and can rotate integrally therewith. The seal portion is formed integrally with the pump block main body, and the pressing means is interposed between the pump block main body and the rotation-side seal disk and is brought into contact with the outer peripheral surface of the seal portion. A liquid discharge device comprising a ring.