Liquid filling device

Abstract

To provide a liquid filling device and a liquid filling method, capable of adjusting, highly accurately in a short time, opening / closing speeds of a liquid channel of a filling liquid based on positional information of a pressing member of a valve device, having good reproducibility of a setting, capable of carrying out equal and excellent liquid filling among a plurality of containers, and capable of preventing liquid dripping.SOLUTION: In the liquid filling device, a liquid channel 5 is provided between a tank 2 storing a liquid to fill and a filling nozzle 3 that injects the liquid into the container. At least a certain section of the liquid channel 5 is formed of a flexible tube 6, and a pinch valve 10 having a pressing member 13 that presses the flexible tube 6 is provided. The pressing member 13 of the pinch valve 10 is provided in a plunger 12 of an air cylinder 11 that can adjust an opening degree and opening / closing speeds of the liquid channel 5 by adjusting an air supply / discharge amount, and includes position detecting means 15 for detecting an axial position of the plunger 12 and displaying means 17 for displaying a result of the detection.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an improvement of a liquid filling device provided with a valve device for filling a container with a liquid. Place

Background Art

[0002] Conventionally, in a liquid filling device, as a technique for filling a container with a fixed amount of liquid, an electric valve device is used which presses and releases a liquid path formed in a tube shape by a flexible (elastic) material such as silicon by a pressing member by the forward and backward driving of a plunger of an air cylinder as a fluid actuator, and not only the start and stop of the filling but also the flow rate is adjusted (see Patent Document 1).

[0003] In order to accurately perform the fixed amount filling of the container by driving the valve device, it is important to adjust the timing of the opening and closing operation of the liquid path in the liquid filling device, and more specifically, the operation time (opening and closing speed) from the start to the end of the forward and backward movement of the plunger for the output of the air cylinder which is the drive source of the filling valve.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] ​In the aforementioned valve device, the opening and closing speed of the liquid passage is controlled by the operator manually turning a screw to adjust the opening degree of the throttle valve, which acts as a speed controller. However, because it was not possible to obtain positional information of the pressing member when moving the output plunger of the air cylinder back and forth, settings were not reproducible when changing models, switching liquid types, or changing liquid volumes. Adjusting the opening and closing speed with high precision and uniformity required a high level of skill from the operator, making it an extremely difficult task.

[0006] Furthermore, in liquid filling equipment that uses valve devices corresponding to each of multiple containers, it was difficult to equalize the opening and closing speeds of the liquid pathways in all valve devices, requiring a lot of time for adjustment.

[0007] This invention was made in view of the above problems, and enables high-precision and rapid adjustment of the opening and closing speed of the liquid passage of the filling liquid based on the position information of the pressing member of the valve device, and also offers high reproducibility of settings, enabling uniform and good liquid filling even among multiple devices, and preventing the occurrence of liquid dripping. Place The purpose is to provide. [Means for solving the problem]

[0008] To achieve the aforementioned objectives, the present invention provides a liquid filling apparatus comprising a liquid passage for guiding the liquid between a tank storing the liquid to be filled and a filling nozzle for injecting the liquid into a container, wherein at least a certain section of the liquid passage is made of a flexible tube, and a pinch valve is provided which has a movable pressing member for pressing the flexible tube, wherein the pressing member of the pinch valve is provided on a plunger of an air cylinder capable of adjusting the opening degree and opening / closing speed of the liquid passage by adjusting the amount of air supplied and discharged, and the apparatus is characterized by comprising a position detection means for detecting the axial position of the plunger and a display means for displaying the result of the detection.

[0009] Furthermore, the system is characterized by providing a calculation means for calculating the movement speed of the plunger based on the detection result of the position detection means, and the display means for displaying the result of the calculation, and the position detection means being a potentiometer.

[0010] With this liquid filling device, it becomes possible to numerically control the opening and closing operation (position and speed) of the pressing member that opens and closes the liquid flow path, which is made of a flexible tube, while using inexpensive air cylinders and potentiometers. Therefore, these adjustments can be made easily and accurately without relying on the operator's experience or intuition.

[0011] Furthermore, the liquid filling device is characterized in that multiple pressing members are provided along the liquid passage, and when filling the liquid, the amount of pressure on the flexible tube is changed by moving the pressing member back and forth between the furthest forward position in which the flexible tube is fully closed and the reference position in which it is fully open, thereby controlling the liquid flow rate, and when filling is stopped, with the upstream pressing member advanced to the forward position in which the flexible tube is fully closed, at least one downstream pressing member is moved back from the position in which the flexible tube is pressed and the liquid passage is narrowed toward the reference position.

[0012] With this liquid filling apparatus, the opening and closing of the liquid flow path, which is made of flexible tubes, can be easily and accurately adjusted by numerically understanding the opening and closing movements (position and speed) of each of the multiple pressing members arranged in the upper and lower stages, without relying on the operator's experience or intuition. When filling stops, the volume inside the flexible tube is increased more reliably, causing a suck-back phenomenon to draw up the liquid inside the filling nozzle and preventing dripping. [Effects of the Invention]

[0015] As described above, the liquid filling device of the present invention PlaceTherefore, based on the position information of the pressing member of the valve device, the opening and closing speed of the liquid passage for the filling liquid can be adjusted with high precision and in a short time, the settings are highly reproducible, uniform and good liquid filling can be performed across multiple units, and the occurrence of liquid dripping can be prevented. [Brief explanation of the drawing]

[0016] [Figure 1] Schematic diagram showing the overall configuration of the liquid filling apparatus according to the first embodiment of the present invention. [Figure 2] Schematic diagram showing the main components of a liquid filling apparatus according to a second embodiment of the present invention. [Modes for carrying out the invention]

[0017] Hereinafter, embodiments of the liquid filling apparatus of the present invention will be described with reference to Figures 1 and 2.

[0018] As shown in Figure 1, the liquid filling apparatus of this embodiment performs a quantitative filling process of liquid L such as beverages or dressings into a container A placed on a table 1 which serves as the filling position. The apparatus comprises a tank 2 for storing the liquid L to be filled, a filling nozzle 3 located above the container A at the filling position, a liquid flow path 5 having a pipe 4 connecting the tank 2 and the filling nozzle 3, and a flexible tube 6 arranged in a certain section of the liquid flow path 5 and constituting the liquid flow path 5 together with the pipe 4.

[0019] In this embodiment, the flexible tube 6 is formed in a circular cross-section tube shape from a flexible (elastic) material such as silicone provided in the liquid channel 5, and is connected to the end portion of the piping 5 connected to the tank 2.

[0020] Furthermore, the support body 7 that supports the piping 4 constituting the liquid flow path 5 is equipped with a wall member 8 arranged along the liquid flow path 5 and an operating means 9 that presses a flexible tube 6 between itself and the wall member 8 to open and close the liquid flow path 5.

[0021] The actuating means 9 is a pinch valve that presses or releases the flexible tube 6 in the liquid flow path 5 where the flexible tube 6 is disposed, thereby performing an opening / closing operation of the liquid flow path 5. In the present embodiment, an inexpensive air cylinder 11 is adopted, which can adjust the advancing / retreating speed by adjusting the air supply volume. The air cylinder 11 is disposed on the support 7 such that the plunger 12 moves forward and backward in a direction perpendicular to the surface of the wall member 8 facing the flexible tube 6, and a pressing member 13 that contacts and separates from the flexible tube 6 is provided at the tip of the plunger 12.

[0022] This pressing member 13 is formed of a relatively hard material so as to have a contact surface wider than the inner diameter (width) of the flexible tube 6 closed by pressing.

[0023] In the liquid filling device of the present embodiment, there are provided a timing means 19, a potentiometer 15 provided on the plunger 12 as a position detection means 14 for detecting the advancing / retreating position of the plunger 12 in the axial direction, a control unit 16 that calculates the opening / closing speed from the detection results, and a display means 17 that displays the detection results and the calculation results.

[0024] Based on various pre-input and set information regarding filling, detected or calculated numerical values, for example, the filling amount per unit time, the time required for filling the liquid L1g, the timing of the opening / closing operation of the liquid flow path 5 by the air cylinder 11, the position (reference position) of the plunger 12 in a state where the pressing member 13 does not contact the flexible tube 6 and the liquid flow path 5 is fully opened, the position (most advanced position) of the plunger in a state where the pressing member 13 strongly sandwiches and presses the flexible tube 6 between it and the wall member 8 to fully close and block the liquid flow path 5, the time required for the opening / closing operation, the opening / closing speed, etc., the control unit 16 controls the driving of the air supply source 18 that supplies and discharges air to the air cylinder 11, moves the plunger 12 forward and backward between the reference position and the most advanced position, and is configured to switch the filling state.

[0025] In this embodiment, the movement of the plunger 12 when increasing the pressure of the pressing member 13 on the flexible tube 6 is conceptualized as "advancing" and the direction of that movement as "forward," while the movement of the plunger 12 when decreasing the pressure on the flexible tube 6 is conceptualized as "retracting" and the direction of that movement as "rearward."

[0026] In the liquid filling apparatus of this embodiment configured as described above, the operating means 9 acts as a filling valve as follows. The description of the operation and effects of the liquid filling apparatus of this embodiment is based on the present invention. by Detailed information on liquid filling methods Explanation .

[0027] When container A is supplied directly below the filling nozzle 3, which is the filling position for liquid L, the control unit 16 in the operating means 9 drives the air supply source 18, advancing the plunger 12 of the air cylinder 11 to its furthest forward position, and the pressing member 13 located at the tip of the plunger 12 presses the flexible tube 6 between itself and the wall member 8, thereby closing the liquid flow path 5.

[0028] The liquid L supplied from the liquid tank 2 flows into the flexible tube 6 from the piping 4, which serves as the liquid flow path 5. However, the liquid L is not sent to the filling nozzle 3, which is located downstream of the point where the pressing member 13 is pressing against the flexible tube 6.

[0029] From this state, the control unit 16 drives the air supply source 18, and the plunger 12 of the air cylinder 11 is retracted from its furthest forward position at a preset opening and closing speed to a reference position where the pressing member 13 does not come into contact with the flexible tube 6, thereby opening the liquid flow path 5. At this time, due to the flexibility of the flexible tube 6, the flexible tube 6, which had been indented by the pressure of the pressing member 13, returns to its original shape, and the liquid L flows down through the liquid flow path 5 made up of the flexible tube 6 by gravity or pressurization applied to the liquid, and is filled into container A from the filling nozzle 3.

[0030] Then, when a specified amount of liquid L is filled into container A, the control unit 16 drives the air supply source 18 to move the plunger 12 of the air cylinder 11 back to its furthest forward position, closing the liquid passage 5 of the flexible tube 6. As a result, the flow of liquid L that was flowing through the liquid passage 5 stops, and the filling is completed.

[0031] In this embodiment of the liquid filling apparatus, which fills a specified amount of liquid L, when controlling the filling based on the forward and backward movement of the plunger 12 for this filling, the forward and backward position of the plunger 12 (pressing member 13) is detected and numerically determined using a potentiometer 15, and the drive of the air cylinder 11 is adjusted as appropriate.

[0032] Specifically, the control unit 16 detects the position information of the plunger 12 numerically from the potentiometer 15 and displays it on the display means 17. Based on this numerical value, the control unit adjusts the setting of the axial movement speed of the air cylinder 11 during the opening and closing operation of the fluid flow path 5. The speed of the air cylinder 11 is adjusted manually using the air cylinder 11 speed controller 20.

[0033] For example, regarding the furthest forward position in which the liquid passage 5 of the flexible tube 6 is closed, the plunger 12 can be moved forward or backward to determine its position by taking into account factors such as whether or not there is liquid leakage and the time required for filling. This fine adjustment can be performed easily, with high reproducibility, and based on numerical values ​​by using a potentiometer 15.

[0034] Furthermore, the opening and closing speed of the liquid flow path 5 can be calculated based on the amount of movement between the reference position and the furthest forward position, and the time available for closing and opening the pinch valve 10 during a single filling cycle.

[0035] Therefore, in this embodiment, the control unit 16 is provided with a calculation means (not shown) that calculates the movement speed of the plunger 12 based on the detection result of the potentiometer 15 and the elapsed time measured by the timing means 19, and the display means 17 displays the result of the calculation to confirm the operating status of the liquid filling device.

[0036] In pressurized filling, where the tank 2 is pressurized to apply pressure to the filling liquid and the filling is carried out using that pressure, the filling time is defined as the time from the moment the pinch valve 10 begins to open and the liquid passage 5 begins to open into the flexible tube 6 until the liquid passage 5 is closed by the closing pinch valve 10. Therefore, if the opening and closing speed of the pinch valve 10 changes, the filling time will change, and the filling amount will change accordingly. Consequently, in a liquid filling device configured to fill multiple containers A simultaneously with a predetermined amount by arranging multiple filling nozzles 3, if the opening and closing speeds of the pinch valves 10 are not standardized, the filling amount will vary for each filling nozzle 3, resulting in inconsistencies.

[0037] However, if the process can be controlled numerically as in this embodiment, the variation in the operating stroke of the pressing member 13 will be reduced, and the filling accuracy will be greatly improved. In particular, even in the case of a liquid filling device configured to fill a predetermined amount at once into multiple containers A supplied simultaneously by arranging multiple filling nozzles 3, it becomes easy to ensure that the amount of liquid filled from each filling nozzle 3 is consistent.

[0038] Furthermore, in the case of piston-type filling, where a fixed amount of filling liquid in tank 2 is drawn by a piston (not shown), the pinch valve 10 is opened, the piston is operated to fill the fixed amount, and then the pinch valve 10 is closed, the filling time is the time the piston moves, and the amount filled is measured by the piston. However, in reality, even after the piston has finished discharging the liquid L and stopped, the liquid L in the piping 4 (flexible tube 6) will still have inertia and will try to come out of the filling nozzle 3. If the closing speed of the pinch valve 20 is slow at this time, a large amount of the liquid in the filling nozzle 3 will come out, resulting in poor liquid drainage after filling and causing dripping.

[0039] Conversely, if the pinch valve 10 is closed too quickly, the flexible tube 6 may be crushed by the closing action of the pinch valve 10, causing the flow velocity of the liquid L corresponding to the volume discharged from the filling nozzle 3 to momentarily increase, which may cause splashing between the liquid surface in the container A being filled and the tube.

[0040] If the opening and closing speed of the liquid passage 5 (pinch valve 10) can be controlled to an appropriate value as in this embodiment, it will be possible to suppress the occurrence of poor liquid drainage, dripping, and splashing after filling as described above.

[0041] Furthermore, as shown in Figure 2, the liquid filling apparatus of this embodiment can also be configured to have two pinch valves 10 equipped with potentiometers 15 on the plungers 12 of the air cylinders 11, arranged in two stages along the liquid flow path 5 of the flexible tube 6. By controlling the drive of each air cylinder 11, suck-back can be performed after quantitative filling to prevent liquid dripping and thus prevent contamination of containers, etc., during filling.

[0042] Specifically, when filling with liquid L, the amount of pressure applied to the flexible tube 6 is changed by moving it back and forth between the furthest forward position where the liquid passage 5 of the flexible tube 6 is fully closed and the reference position where the liquid passage 5 is fully open, thereby controlling the flow rate of liquid L. When filling is stopped, with the pressing member 13 of the air cylinder 11 acting as an upstream pinch valve advanced to the forward position where the flexible tube 12 is fully closed, the pressing member 13 of the air cylinder 11 acting as a downstream suck-back valve is controlled to move from a predetermined position where the flexible tube 12 and the flexible tube 6 are pressed to narrow the liquid passage 5, to a position (suck-back position) that is retracted towards the reference position. Figure 2 shows the positional relationship of the upper and lower air cylinders 11 in the state when this suck-back is being performed. This retraction of the downstream pressing member 13 draws up the small amount of liquid remaining in the liquid channel 5 downstream of the point where the pressing member 13 is pressing the flexible tube 6, creating a concave meniscus at the tip of the filling nozzle 3. This creates a liquid surface shape that is resistant to dripping due to surface tension, preventing dripping after filling and preventing contamination of containers, etc., during filling (suck-back effect).

[0043] If, for the same liquid L, the amount of retraction of at least one downstream pressing member 13 necessary to properly generate suck-back, i.e., the suck-back position, can be numerically determined using a potentiometer 15, then even in the case of a liquid filling device configured to fill a predetermined amount at once into multiple containers A supplied simultaneously by arranging multiple filling nozzles 3, that numerical value can be applied to each filling nozzle. This makes it possible to easily and reliably prevent liquid dripping by suck-back without relying on the operator's experience or intuition to adjust the amount of advancement (stroke) of the air cylinder 11.

[0044] Furthermore, the present invention is not limited to the embodiments described above, and can be modified in various ways without impairing the features of the present invention.

[0045] For example, in the filling method of the present invention, even if a liquid filling apparatus is configured to fill a predetermined amount at once into a plurality of containers A supplied simultaneously by arranging a plurality of filling nozzles 3, it is not necessary to permanently install one potentiometer on each air cylinder corresponding to each of the filling nozzles 3. Instead, one potentiometer may be attached to and detached from the plunger of each air cylinder, and the position of the pressing member that opens and closes the liquid flow path, which is made of a flexible tube, may be repeatedly determined numerically. [Explanation of Symbols]

[0046] 1 table 2 tanks 3. Filling nozzle 4 Piping 5 Liquid flow path 6. Flexible tubing 7 Support 8 Wall components 9. Operating means 10 Pinch valve 11 Air Cylinder 12 plungers 13 Pressing member 14 Position detection means 15 Potentiometer 16 Control Unit 17 Display means 18 Air supply source 19 Timekeeping means 20 Speed ​​Controller L liquid A container

Claims

1. A liquid filling device comprising a tank storing the liquid to be filled and a filling nozzle for injecting the liquid into a container, wherein a liquid passage is provided to guide the liquid between the tank and the filling nozzle, at least a certain section of the liquid passage is made of a flexible tube, and a pinch valve is provided which has a movable pressing member for pressing the flexible tube, Multiple pinch valves are provided along the liquid passage on the plunger of an air cylinder, which can adjust the opening degree and opening / closing speed of the liquid passage by adjusting the amount of air supplied and discharged. During liquid filling, the pinch valve moves back and forth between the furthest forward position where the flexible tube is fully closed and the reference position where it is fully open to change the amount of pressure on the flexible tube and control the liquid flow rate. When filling is stopped, with the upstream pressing member advanced to the forward position where the flexible tube is fully closed, at least one of the downstream pressing members is retracted from the furthest forward position where the flexible tube is fully closed towards the reference position. A position detection means for detecting the axial position of the plunger, Display means for displaying the results of the detection A liquid filling apparatus characterized by comprising the following features.

2. A calculation means is provided to calculate the movement speed of the plunger based on the detection result of the position detection means. The liquid filling apparatus according to claim 1, characterized in that the display means displays the result of the calculation.

Images