Dispensing device and lubricant application method for dispensing device

Abstract

In order to provide a dispensing device capable of quantitatively and uniformly applying a lubricant and a lubricant application method for the dispensing device, the present invention is configured in the manner described below.　This dispensing device comprises: a lubricant application block comprising a nozzle insertion port into which a dispensing nozzle can be inserted while maintaining a predetermined airtightness, a lubricant tank for storing a lubricant to be applied to the nozzle tip of the dispensing nozzle, and a lubricant discharge port for discharging the lubricant from the lubricant tank to the nozzle insertion port; a negative pressure source for creating negative pressure inside the dispensing nozzle and sucking the liquid into the dispensing nozzle; and a control unit that performs control for causing the lubricant to adhere to the tip of the dispensing nozzle by creating negative pressure inside the dispensing nozzle by means of the negative pressure source after the the dispensing nozzle is inserted into the nozzle insertion port and pulling the lubricant from the lubricant discharge port into the nozzle insertion port. Also provided is a lubricant application method for the dispensing device.

Description

Dispensing device and lubricant application method for dispensing device

[0001] The present invention relates to a dispensing device and a method for applying a lubricant to a dispensing device.

[0002] To prevent contamination during sample dispensing, some dispensing devices (dispensers) for testing equipment use dispensing nozzles equipped with dispensing tips. Such nozzles are fitted with a seal (rubber ring) to maintain airtightness with the dispensing tips. To reduce wear on the rubber ring and maintain airtightness, a lubricant is applied to the contact surface with the dispensing tips. The lubricant on the rubber ring is consumed each time a tip is discarded, so it must be applied periodically.

[0003] Patent Document 1 discloses a method for applying lubricant (grease) to an O-ring at the tip of a nozzle, in which a grease application table is provided and the grease is applied by inserting a nozzle into a through-hole provided in the grease impregnation section. A grease impregnation section is provided inside the grease application table, and the grease impregnation section is made of a sponge-like porous resin material impregnated with grease components. The grease impregnation section has through-holes provided at positions corresponding to the arrangement of the nozzles, and by inserting the nozzles into these through-holes, the O-ring at the lower end of the nozzle comes into contact with the grease impregnation section, and the grease components are applied.

[0004] Japanese Patent Application Laid-Open No. 2005-257704

[0005] In the technology described in Patent Document 1, grease is applied by inserting a nozzle into a through-hole provided in the grease-impregnated section. However, since the grease application is simply performed by inserting the nozzle into the through-hole provided in the grease-impregnated section, it appears difficult to ensure that the same amount of lubricant is always applied to the tip of the dispensing nozzle.

[0006] An object of the present invention is to provide a dispensing device capable of applying a lubricant quantitatively and uniformly, and a lubricant application method for the dispensing device.

[0007] The present invention achieves the above object by providing a dispensing device and a method for applying lubricant to a dispensing device, the method comprising: a lubricant application block including a nozzle insertion port into which a dispensing nozzle can be inserted while maintaining a predetermined airtightness, a lubricant tank that stores lubricant to be applied to the tip of the dispensing nozzle, and a lubricant outlet port that discharges the lubricant from the lubricant tank into the nozzle insertion port; a negative pressure source that creates a negative pressure inside the dispensing nozzle to draw liquid into the dispensing nozzle; and a control unit that, after inserting the dispensing nozzle into the nozzle insertion port, creates a negative pressure inside the dispensing nozzle using the negative pressure source and draws the lubricant from the lubricant outlet port into the nozzle insertion port, thereby depositing the lubricant on the tip of the dispensing nozzle.

[0008] According to the present invention, it is possible to provide a dispensing device capable of applying a lubricant quantitatively and uniformly, and a lubricant application method for a dispensing device.

[0009] 1 is a schematic diagram of a dispensing device; a cross-sectional view of a nozzle portion of the dispensing device; a schematic diagram of a lubricant application block; a diagram showing an example of a lubricant tank; a diagram showing a lubricant application operation flow; a flowchart of the lubricant application operation; a diagram showing a method of filling a lubricant; a top view of a lubricant block of Example 2; a top view of a lubricant block of Example 3; a diagram showing a lubricant filling method of Example 4; a cross-sectional view of a lubricant block of Example 5; a diagram showing a lubricant filling method of Example 5; a cross-sectional view of a lubricant block of Example 6; a cross-sectional view of the lubricant filling port of the lubricant block of Example 1 with a rubber lid attached.

[0010] Hereinafter, an embodiment of the present invention will be described using a dispensing device of a genetic testing device as an example. Note that the present invention is applicable not only to genetic testing devices but also to general dispensing devices equipped with a sealing material at the tip.

[0011] 1 is a diagram showing an example of a dispensing device 100 according to the present invention. The dispensing device 100 includes a base 101 having an overall L-shaped configuration, and a motor 102 is provided on the upper part of the base 101. A screw shaft 104, which is a trapezoidal screw, a ball screw, or the like, is rotatably provided on the base 101 and is connected to the rotary shaft of the motor 102 via a coupling 103.

[0012] The screw shaft 104 is provided with a slider 106 through which the screw shaft 104 passes and a nut 105 that is screwed onto the screw shaft 104. The slider 106 is connected to a linear guide 107 provided on the base 101, and the nut 105 and the slider 106 are each free to move or slide up and down in the direction of the arrow S shown in the figure. The slider 106 is also joined to a piston 108 that protrudes downward, and is configured to move up and down without rotating.

[0013] The piston 113 (hereinafter also referred to as the "plunger") and the piston receiving portion 115 (hereinafter also referred to as the "syringe") constitute a pipette mechanism, and the above-mentioned vertical movement mechanism functions as a pump. A disposable tip 311 (hereinafter also referred to as the "dispensing tip") is attached to the tip of the piston receiving portion 115. A tip removal portion 911 is provided above the disposable tip 311. The tip removal portion 911 has a U-shaped notch or a through-hole with a diameter smaller than the diameter of the opening of the disposable tip 311. A spring or other spring material 912 connected to the upper end of the tip removal portion 911 and the base 101 constantly biases the tip removal portion 911 upward and allows it to move up and down along the arrow S. Furthermore, to dispense into small containers installed in various locations within the device, the dispensing device 100 is installed on an automatic stage (not shown) that can be freely driven horizontally and vertically. The motor 102 is electrically connected to a control PC (Personal Computer) 901 and is controlled by a control signal.

[0014] FIG. 2 shows a cross-sectional view of the plunger 113, syringe 115, and the surrounding area (nozzle portion) of FIG. 1 . When the plunger 113 is inserted into or removed from the syringe 115, negative pressure is created within the dispensing nozzle tip 112, causing liquid to be drawn into the dispensing tip 311 attached to the dispensing nozzle tip 112. When positive pressure is created at the dispensing nozzle tip 112, the drawn liquid is discharged. In this embodiment, the plunger 113 and syringe 115 form a negative pressure source. As the negative pressure source, in addition to the structure in which the dispensing nozzle tip 112, plunger 113, and syringe 115 are integrated as shown in FIG. 2 , a negative pressure source (other than the combination of the plunger 113 and syringe 115, such as a peristaltic pump) provided separately from the dispensing nozzle tip 112 may also be provided.

[0015] In this embodiment, the plunger 113 contacts a plunger seal 114 to maintain airtightness. Because the dispensing device aspirates and dispenses a variety of different liquids, a disposable dispensing tip 311 is attached to the dispensing nozzle tip 112 to prevent the different liquids from mixing and affecting the analysis results (to prevent contamination). To maintain airtightness between the dispensing nozzle tip 112 and the dispensing tip 311, a nozzle tip seal 111 made of an O-ring or the like is provided at the dispensing nozzle tip 112.

[0016] A microplate is an example of a target into which the dispensing device 100 dispenses liquid. The wells of a microplate tend to become smaller in size in order to increase the number of wells to improve testing efficiency and reduce the internal volume in order to reduce the consumption of reagents.

[0017] For example, in addition to the conventional 96-well type, 384-well types have come into use, with the well size roughly halved and the number of wells four times greater than before. This has led to an increase in the frequency with which dispensing tips are inserted and removed from the tip of the dispensing nozzle. This can lead to the wear of the lubricant applied to the nozzle tip sealant 111 at the tip of the dispensing nozzle 112, reducing the sealing ability between the dispensing tip 311 and the nozzle tip sealant 111 and potentially affecting dispensing accuracy.

[0018] Referring to FIG. 3 , the lubricant application mechanism for the nozzle tip sealant 111 according to this embodiment will be described. As shown in FIG. 3 , the lubricant application block 201 according to this embodiment is composed of a nozzle insertion port 211, a lubricant tank 212, a lubricant discharge port 213, a lubricant filling port 214a, and a lubricant filling port 214b. The diameter of the nozzle insertion port 211 is large enough to ensure sufficient adhesion between the nozzle tip sealant 111 and the dispensing nozzle tip 112 when the dispensing nozzle tip 112 is inserted into the lubricant application block 201. The lubricant tank 212 stores a lubricant. For example, grease or the like can be used as the lubricant. The lubricant discharge port 213 is positioned below the position of the nozzle tip sealant 111 when the dispensing nozzle tip 112 is inserted.

[0019] 4 shows a view from above of the structures of the lubricant tank 212 and the lubricant discharge port 213. The lubricant tank 212 and the lubricant discharge port 213 are arranged at circumferential positions centered on the nozzle insertion port 211. The lubricant discharge port 213 faces the nozzle insertion port 211 and is arranged concentrically with the center of the nozzle insertion port 211. In other words, when viewed from the nozzle insertion port 211 side, the lubricant discharge port 213 is arranged in a band shape so as to surround the nozzle insertion port 211.

[0020] The nozzle insertion port 211 has a blind hole structure (a structure with a bottom) that becomes sealed after the dispensing nozzle tip 112 is inserted, making it usable for leak tests (air leak detection). A leak test is a test to determine, for example, whether the plunger seal 114 has deteriorated and its sealing performance has decreased (i.e., whether air outside the syringe 115 is sucked in through the gap in the plunger seal 114 when the plunger 113 is pulled from the syringe 115). In this case, a pressure sensor (not shown) is provided to measure the pressure inside the syringe 115 (inside the dispensing nozzle tip 112), and the pressure measured when the plunger 113 is operated can be measured. The presence or absence of a leak can be determined based on the measured pressure value. Furthermore, if the negative pressure source is provided at a distance from the dispensing nozzle tip 112 as described above, a pressure sensor may be provided in a portion of the piping (flow path) connecting the negative pressure source to the dispensing nozzle tip 112. When used for a leak test, in order to reliably maintain the airtightness of the block, lids may be added to the lubricant filling port 214a and the lubricant filling port 214b as shown in FIG.

[0021] Next, an example of the lubricant application operation flow of this embodiment will be described with reference to FIGS. 5A and 5B. When applying lubricant 312 to the nozzle tip sealant 111 of the dispensing nozzle tip 112, first, the dispensing nozzle tip 112 is inserted into the nozzle insertion port 211 of the lubricant application block (FIG. 5A(a) and S502 in FIG. 5B). Next, a suction operation is performed on the dispensing nozzle, i.e., the plunger 113 is moved upward to create a negative pressure inside the plunger 113, thereby drawing the lubricant 312 stored in the lubricant tank 212 toward the nozzle insertion port 211 (FIG. 5A(b) and S503 in FIG. 5B). The lubricant 312 drawn toward the nozzle insertion port 211 adheres to the dispensing tip. The dispensing nozzle is then removed from the lubricant application block 201 (S504 in FIG. 5B). Next, the dispensing tip 311 is attached. When the dispensing tip 311 is attached, the lubricant 312 adheres to the inside of the dispensing tip, and the inside of the lubricated dispensing tip comes into contact with the nozzle tip sealant 111. As the lubricant 312 adheres to the contact surface between the nozzle tip sealant 111 and the dispensing tip 311, the lubricant is applied to the nozzle tip sealant 111 (Figure 5(c), S505 in Figure 5B).

[0022] With this configuration, the lubricant is discharged by the suction force of the dispensing device, so the amount of lubricant applied to the sealing material can be controlled. That is, after a sufficient amount of lubricant is stored in the lubricant tank of the lubricant application block, the lubricant is transferred from the lubricant discharge port to the nozzle insertion port by the suction force of the dispensing device, making it possible to apply the same amount of lubricant to the sealing material every time.

[0023] The lubricant attached to the tip of the dispensing device in the lubricant application block is transferred to the inside of the dispensing tip when the tip is attached. The inside of the lubricated tip then comes into contact with the sealing material, and the lubricant is applied to the contact surface between the sealing material and the dispensing tip, allowing the lubricant to be applied evenly to the sealing material.

[0024] The lubricant application work is performed by the device, eliminating the need for workers to apply the lubricant, improving operability.

[0025] 6 shows the lubricant filling method of this embodiment. When filling the lubricant 312, a lubricant filling plug 421 is inserted into the nozzle insertion port 211 to block the lubricant discharge port 213. Then, a syringe 401 filled with the lubricant 312 is prepared, and the tip 413 of the syringe is inserted into the lubricant filling port 214a to fill the lubricant 312 into the lubricant tank 212. Filling is complete when the lubricant 312 spills out of the lubricant filling port 214b. It is also possible to fill the lubricant into the lubricant filling port 214b and continue filling until the lubricant spills out of the lubricant filling port 214a.

[0026] 7 , lubricant discharge port 511 is not strip-shaped, but has multiple openings arranged radially at the center of nozzle insertion port 211. In Example 2, when lubricant is sucked, lubricant 312 that adheres to dispensing nozzle tip 112 adheres only to the location of the opening of lubricant discharge port 511, making it possible to reduce the amount of lubricant 312 used.

[0027] In the third embodiment, the lubricant discharge port 511 has the same structure as in the second embodiment, and as shown in Fig. 8, the lubricant tank 611 is divided into multiple tanks, which are arranged at circumferential positions around the nozzle insertion port 211. In the third embodiment, when filling the lubricant, the lubricant can be filled into all the tanks at the same time, which shortens the filling time of the lubricant compared to the lubricant application block in Fig. 3. In addition, the lubricant can be filled more or less uniformly.

[0028] In Example 4, as shown in Fig. 9, one lubricant filling port 711 and a strip-shaped lubricant discharge port 712 are provided at the top of the lubricant tank. When filling the lubricant, the lubricant is poured through the lubricant filling port 711 and is completed when the lubricant spills out of the lubricant discharge port 712. Compared to the configuration in Fig. 6, this configuration requires only one lubricant filling port, which makes manufacturing easier and is expected to reduce costs.

[0029] In Example 5, as shown in Fig. 10(b), the portion of the lubricant application block above the lubricant tank 212 serves as a lid 811, and has a structure that can be separated from the lubricant application block 812 shown in Fig. 10(c). When the nozzle insertion opening 821a is fixed coaxially to the nozzle insertion opening 821b as shown in Fig. 10(a), the bottom 822 of the nozzle insertion opening 821a serves as the lubricant discharge opening.

[0030] When refilling the lubricant, the lid 811 is removed, the lubricant filling plug 421 is inserted into the nozzle insertion opening 821b, and the lubricant is directly poured into the lubricant tank 212, as shown in FIG.

[0031] With this structure, the lubricant application block can be manufactured separately as a lid and a block body, which simplifies manufacturing and reduces manufacturing costs. Furthermore, when filling the lubricant tank with lubricant, the lid can be removed, which eliminates the need to inject the lubricant into a small lubricant filling port using a syringe-like filling tool as shown in Figure 4, thereby reducing the time required for filling.

[0032] Furthermore, by using separate structures, it is possible to use different materials depending on the required characteristics of each, such as making the lid out of plastic, which is easy to process, and the block body, which requires a certain degree of strength, out of metal such as aluminum, making it possible to optimize each required characteristic, such as cost, durability, and ease of use.

[0033] While the nozzle insertion port 211 in Example 1 has a blind hole structure, the nozzle insertion port 921 in Example 6 is a through hole as shown in Figure 12. A lid 922 is provided at the bottom of the through hole to maintain airtightness. By using a through hole, the lubricant application block can be easily manufactured. Furthermore, it is easy to clean off any lubricant remaining inside the lubricant application block.

[0034] 100: Dispensing device 111: Nozzle tip sealant 112: Dispensing nozzle tip 113: Plunger 114: Plunger sealant 115: Syringe 201: Lubricant application block 211: Nozzle insertion port 212: Lubricant tank 213: Lubricant outlet 214a: Lubricant filling port 214b: Lubricant filling port 311: Dispensing tip 312: Lubricant 401: Lubricant filling syringe 411: Plunger of lubricant filling syringe 412: Syringe of lubricant filling syringe 413: Tip of lubricant filling syringe 421: Lubricant filling stopper 511: Lubricant outlet of Example 2 512: Lubricant filling port of Example 2 611: Lubricant tank of Example 3 711: Lubricant filling port of Example 4 712: Lubricant tank exhaust port of Example 4 811: Lid of lubricant application block of Example 5 812: Lubricant application block body of Example 5 821a: Nozzle insertion port of lid of lubricant application block of Example 5 821b: Nozzle insertion port of body of lubricant application block of Example 5 822: Bottom of nozzle insertion port of lid of lubricant application block of Example 5 921: Nozzle insertion port of Example 6 922: Cover for bottom of nozzle insertion port of Example 6

Claims

1. A dispensing device comprising: a lubricant application block having a nozzle insertion port into which a dispensing nozzle can be inserted while maintaining a predetermined airtightness; a lubricant tank that stores lubricant to be applied to the tip of the dispensing nozzle; and a lubricant discharge port that discharges the lubricant from the lubricant tank into the nozzle insertion port; a negative pressure source that creates a negative pressure inside the dispensing nozzle to draw liquid into the dispensing nozzle; and a control unit that, after the dispensing nozzle is inserted into the nozzle insertion port, creates a negative pressure inside the dispensing nozzle using the negative pressure source and draws the lubricant from the lubricant discharge port into the nozzle insertion port, thereby adhering the lubricant to the tip of the dispensing nozzle.

2. A dispensing device according to claim 1, wherein the lubricant discharge port opens in a strip shape on the side of the nozzle insertion port.

3. A dispensing device according to claim 1, wherein the lubricant tank is arranged at a circumferential position of a concentric circle with the nozzle insertion opening approximately at its center, and the lubricant discharge opening opens on the inner surface of the nozzle insertion opening in a concentric circle with the nozzle insertion opening approximately at its center.

4. A dispensing device according to claim 3, wherein the lubricant application block has a lubricant filling port that communicates with the lubricant tank and fills the lubricant tank with the lubricant.

5. A dispensing device according to claim 4, characterized in that it has a lubricant filling plug that closes the nozzle insertion opening when the lubricant is filled into the lubricant tank through the lubricant filling opening.

6. A dispensing device according to claim 1, wherein the lubricant discharge port has a plurality of openings on the inner surface of the nozzle insertion port, and the plurality of openings are connected to a plurality of spaces extending radially from the nozzle insertion port approximately as the center, and a single space connects the plurality of spaces.

7. A dispensing device according to claim 1, wherein the lubricant discharge port has a plurality of openings on the inner surface of the nozzle insertion port, the plurality of openings being connected to a plurality of spaces extending radially from the nozzle insertion port approximately as the center, and each of the plurality of spaces having a lubricant tank for storing the lubricant.

8. A dispensing device according to claim 4, wherein the lubricant filling port is provided on the upper surface of the lubricant application block, and the lubricant application block has a discharge port on its side that communicates with the lubricant filling port and discharges lubricant that overflows from the lubricant tank when the lubricant is filled through the lubricant filling port.

9. A dispensing device according to claim 1, wherein the lubricant application block can be divided into at least two parts, one of which has a structure including the bottom surface of the lubricant tank, and the other of which forms the lid of the lubricant tank.

10. A dispensing device according to claim 1, wherein the nozzle insertion port has a blind hole structure at the other end of the opening into which the dispensing nozzle is inserted.

11. A dispensing device according to claim 10, further comprising a pressure sensor for measuring the pressure inside the dispensing nozzle, wherein the control unit, after inserting the dispensing nozzle into the nozzle insertion port, creates a negative pressure inside the dispensing nozzle using the negative pressure source, and determines whether or not a leak has occurred between the dispensing nozzle and the negative pressure source based on the pressure value inside the dispensing nozzle measured by the pressure sensor.

12. A lubricant application method for a dispensing device comprising: a lubricant application block including: a nozzle insertion port into which a dispensing nozzle can be inserted while maintaining a predetermined airtightness; a lubricant tank that stores lubricant to be applied to the nozzle tip of the dispensing nozzle; and a negative pressure source that creates a negative pressure inside the dispensing nozzle and draws liquid into the dispensing nozzle, the method comprising: inserting the dispensing nozzle into the nozzle insertion port; and creating a negative pressure inside the dispensing nozzle with the negative pressure source and drawing the lubricant from the lubricant discharge port into the nozzle insertion port, thereby adhering the lubricant to the tip of the dispensing nozzle.

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