JPH02152603A - Filling apparatus for preventing residual liquid from dropping - Google Patents

Abstract

PURPOSE:To draw residual liquid from the end of a nozzle by communicating the interior of a liquid tank with that of a filling cylinder through a switching valve and moving up a piston to make a predetermined displacement so as to measure and leave the filling liquid in the filling cylinder. CONSTITUTION:At the start of suction, a switching valve 8 is rotated at an angle of 90 deg. by the action of an air cylinder 14 and a switching lever 13, whereby the interior of a tank 1 is communicated with that of filling cylinder 9 through a hole 10 and a liquid passage. When raising a piston 9 by operating a servomotor 16, a predetermined amount of liquid is introduced into the filling cylinder 9 to be weighed. The switching valve 8 is then rotated reversely at an angle of 90 deg. to close the hole 10 with the switching valve 8 in order to communicate the interior of the filling cylinder 9 with a filling nozzle 6. Upon downward movement of a piston 3, the liquid in the filling cylinder 9 is sent from the filling nozzle 6 into a container 18 through a hole 11 of the switching valve 8. The upward movement of the piston 3 to an appropriate height draws the residual liquid l from a nozzle 11 into a passage (a) by suction.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a liquid filling machine that measures the amount of liquid filled by the operation of a piston that fills various containers with liquid, and in particular prevents residual liquid from dripping from the filling nozzle. The present invention relates to a liquid filling machine that is capable of ensuring accurate filling amount at the same time.

(Prior art) For example, Japanese Patent Laid-Open No. 56-41196 and Japanese Patent Laid-Open No. 56-14219 disclose methods for preventing residual liquid in this type of liquid filling machine.
There are some that are shown in Publication No. 0, etc. However, in these liquid filling machines, the actuation of the piston and the measurement of the filling amount are not directly performed, so there is no consideration given to variations in the filling amount, and therefore it is especially difficult to fill liquids containing pulp. In some cases, if pulp remains in the liquid reservoir, the filling amount will vary significantly.

Additionally, the devices disclosed in the above publications have a large number of parts;
Since it has a complicated structure, it leads to a cost increase and its management becomes extremely complicated.

(Problem to be Solved by the Invention) In other words, in conventional liquid filling machines, even after filling a container with liquid, the remaining liquid adhering to the nozzle forms a drip and drips onto the edge of the container while the container is being moved. There was a problem that dripping onto the machine could cause sealing failures or staining failures. Further, there is a problem that the amount of filling varies due to dripping of the liquid, making it impossible to perform accurate filling. On the other hand, the above-mentioned Japanese Patent Application Laid-Open No. 56-4119
The technique disclosed in Japanese Patent Laid-Open No. 56142190 uses the deformation of a supply pipe that can be deformed by external force to suction the liquid remaining at the tip of the nozzle, so its operation is not reliable. The technology disclosed in the publication suctions the liquid dripping from the outer periphery to the nozzle tip, and cannot directly suction the liquid adhering to the tip of the nozzle flow path, so it is not possible to completely prevent dripping. Furthermore, since both systems do not directly suction residual liquid through the operation of a piston that forms part of the metering section, there are many variations in the amount of filling, and the structure is complex and has many parts, requiring a great deal of effort to maintain. There is a need.

The present invention was developed to solve these problems, and uses a piston that forms a part of the measuring section to reliably suck the liquid adhering to the filling passage with a simple structure, and also uses a liquid reservoir at the time of measuring. It is an object of the present invention to provide a filling device for preventing dripping of residual liquid, which eliminates variations in the amount of filling by separating the liquid from the filling passage.

(Means for Solving the Problems) For this reason, the present invention provides a liquid filling device that measures the amount of liquid filled by operating a piston within a cylinder, in which the interior of the cylinder is switched to a liquid filling path or a liquid supply path. A filling device for preventing residual liquid dripping, comprising a valve, a piston whose operation timing and stroke can be arbitrarily set, and a driving means for operating the piston with a set suction stroke after liquid filling is completed, This is a means to solve the above problem.

(Function) When measuring liquid, the inside of the liquid tank and the inside of the filling cylinder are communicated via the switching valve, and the piston is raised by a set stroke to measure and store the filling liquid inside the filling cylinder.

When filling liquid, switch the switching valve to communicate the inside of the filling cylinder and the filling nozzle, and push the piston to the lower limit position.

Due to the above-mentioned operation of the piston, the liquid in the filling cylinder passes through the filling passage of the switching valve and is filled into the container from the tip of the filling nozzle.

When filling is completed, the piston moves up by an appropriately set suction stroke to suck out the remaining liquid at the tip of the nozzle. Thereafter, the switching valve is switched again to close the liquid filling path and open the liquid supply path.

(Example) Embodiments of the present invention will be described below based on the drawings.

FIG. 1 is a cross-sectional side view showing the main parts of a filling device for preventing dripping of residual liquid, which is a typical embodiment of the present invention. In this embodiment, a cylinder and a switching valve are integrally provided at the bottom of the liquid tank.

In FIG. 1, reference numeral 1 denotes a liquid tank containing a filling liquid, and a support stand 19 is erected above the tank 1 to vertically support a ball screw 17 which is rotationally driven by a servo motor 16 together with the servo motor 16. A slide table 7 is engaged with the ball screw 17, and the slide table 7 moves up and down in the vertical direction according to the rotation of the ball screw 17. A support member 2 that supports the rond end of the piston 3 is fixed to the slide table 7. The piston 3 is inserted into a filling cylinder 9 formed at the bottom of the liquid tank 1 from the upper open end thereof, and slides inside the cylinder 9 in a liquid-tight manner. 9
' is a closing member of the filling cylinder 9, and the closing member 9' has a blind hole equal to the inner diameter of the cylinder 9 and a through hole formed adjacent to the blind hole. Further, the blind hole and the through hole of the closing member 9' are connected through a liquid passage 11. The closing member 9' is fixed to the bottom back surface of the liquid tank 1 so that the center of the blind hole matches the center of the inner diameter of the filling cylinder 9, and the center of the through hole matches the center of the bottom through hole of the liquid tank 1. be done.

A filling nozzle 6 is fixed to the closing member 9' with the center of its filling passage aligned with the eccentric position of the through hole of the closing member 9'.

Reference numeral 8 denotes a switching valve that is liquid-tightly fitted into the re-penetration hole of the liquid tank 1 and the closing member 9', and the switching valve 8 has a through hole 10 that communicates the liquid tank 1 with the filling cylinder 9; A through hole 11 that connects the filling cylinder 9 and the filling nozzle 6 is 9.
A lever 13 is attached to the rond end of the switching valve 8 that protrudes outward from the upper outer casing 12 of the liquid tank 1, and this lever 13 engages with the air cylinder 14. 9 centered on the axis of the switching valve 8
By rotating it by 0°, it can be switched to either of the through holes 10, 11 as shown in FIG.

On the other hand, the piston 3 inserted into the cylinder 9 is engaged with the support member 2 via the iron as described above, and as the slide table 7 and the support member 2 move up and down, the piston 3
It is designed so that vertical movement is given to . The amount of this vertical movement, that is, the stroke amount of the piston 3 is related to the amount of filling to be measured, and can be easily set by a control device (not shown) using the positioning function of the servo motor 16.

Next, its operation will be explained with reference to FIG. When the switching valve 8 is rotated 90 degrees by the action of the air cylinder 14 and the switching lever 13 at the start of suction, the inside of the tank 1 is connected to the filling cylinder 9 through the liquid passage through the through hole 10 as shown in FIG. 2(a).
communicated with the inside of the

Thereafter, as shown in FIG. 2(b), when the servo motor 16 is activated and the piston 3 is pulled up, a predetermined amount of liquid is introduced into the filling cylinder 9 and measured.

Next, when the switching valve 8 is rotated 906 times in the opposite direction at the filling start position, the through hole 10 is closed by the switching valve 8 and the filling cylinder 9 and the filling nozzle 6 communicate with each other, as shown in FIG. When the piston 3 is pushed down from this state as shown in FIG. 2(d), the liquid in the filling cylinder 9 is filled into the container 18 from the filling nozzle 6 through the through hole 11 of the switching valve 8.

After the piston 3 has stopped and filling of the liquid into the container 18 has been completed, when the piston 3 is raised by an appropriate amount, as shown in FIG.
) As shown in (the liquid l remaining in the filling nozzle 11 is sucked into the passage a).

Here, the switching valve 8 is again turned 9 in the opposite direction for the next filling.
Rotate 0°. At this time, the nozzle 6 and the through hole 11 are installed eccentrically as shown in detail in Fig. 3, so by making this position the fixed cycle position, there will be no leakage even if the machine is stopped for a long time, and the dripping will not occur. can be reliably prevented.

Further, the amount of vertical movement of the piston 3, that is, the stroke amount is a measured filling amount determined by the inner diameter of the filling cylinder 9 or the outer diameter of the piston 3, and this charging taffi, that is, the setting of the stroke amount of the piston 3 is controlled by the servo motor 16. With the positioning function, settings can be easily made in a setting section of a control device (not shown) in response to a change in container or liquid type.

Furthermore, the timing of actuating the piston 3 and the suction stroke amount when suctioning the remaining liquid to be dripped from the filling nozzle 6 are different depending on the type of liquid, as the viscosity difference varies depending on the type of liquid. By using the servo motor 16, the settings can be easily changed when changing the operation timing and suction stroke amount as described above.

(Effects of the Invention) As described above in detail, the present invention provides the following extremely advantageous effects.

(1) A drive device using a servo motor makes it possible to control the pistons placed in each container arrangement, making it possible to arbitrarily change the settings of the suction stroke and operation timing according to the liquid type, and The number of parts can be reduced to reduce the size, and the simple structure ensures drip prevention.

(2) By adopting a simple structure in which the filling hole is eccentric, a separate shut-off valve (
It also prevents dripping due to leakage without providing an on-off valve.

(3) Since the remaining liquid is sucked using the metering mechanism as is, it is possible to suction the remaining liquid in the filling nozzle and the liquid in the passage between the filling cylinder and the nozzle very effectively and directly.
Accurate filling amount can be ensured.

[Brief explanation of the drawing]

FIG. 1 is a side view showing a part of a filling device for preventing dripping of residual liquid according to a typical embodiment of the present invention, FIG. FIG. 2 is a sectional view taken along line A-A in FIG. 2(a). Explanation of the main parts of the diagram 3--Piston 6-(Filling) nozzle 8--Switching valve 9--(Filling) cylinder 10.11-Through hole 16- Servo motor 732 (a) (t)) (C ) Figure 3 Figure 1 (d) (e)

Claims (1)

[Claims] In a liquid filling device that measures the amount of liquid filled by operating a piston within a cylinder, a switching valve that switches the inside of the cylinder to a liquid filling path or a liquid supply path, and a piston whose operation timing and stroke can be set arbitrarily; A filling device for preventing residual liquid dripping, comprising a driving means for operating the piston with a set suction stroke after liquid filling is completed.