JPH059357Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Purpose of the invention [Field of industrial application] The present invention relates to a screw capper attached to a liquid filling device.

[Prior Art] Devices for automatically filling and closing liquid containers with screw-tight lids have been implemented and in operation for some time, in which empty containers with caps are placed on a conveyor. The caps are sequentially transported to a predetermined location, and at that location, the caps are held and rotated from the transported empty container.
After removing the cap from the mouth and opening the container, and filling a certain amount of contents into the container through the opening, place the previously removed screw cap on the mouth of the container again and rotate it in the opposite direction. , tighten the cap.
Once the container is fixed and the lid is closed, the filled and lidded container is then transported from the same position, and the process is repeated.

Conventionally, this type of mechanism, called a screw cap, which removes and holds the screw cap from the mouth of an empty container and re-caps the filled container, has a complicated structure. However, there were problems in that it was difficult to adjust and therefore required a lot of manpower to maintain and manage.

An example of a screw cap handled by the screw capper mentioned above is shown in FIGS. 2a and 2b, a sectional view and a plan view thereof. Figure 2a
21 is a cylindrical cap with a bottom, molded using hard synthetic resin, and ribs 22 extending along the generatrix direction are arranged at equal intervals on the cylindrical outer periphery, and ribs 22 are provided on the cylindrical inner side to connect to the injection port of the container. A female thread 23 is provided for screwing.

A thin inner cover 24 made of soft synthetic resin is fitted into the cylindrical inner bottom, and its free end is slightly tapered, but its actual outer diameter is slightly larger than the inner diameter of the injection port. When the cap 21 is screwed onto the injection port and tightened, the cap 21 is elastically strained, its outer diameter is contracted, and the cap 21 is fitted into the injection port, thereby sealing the gap between the two.

The rib 22 provided on the outer periphery of the cap
It is also useful as a member for receiving torque when screwing the cap into or loosening it from the inlet, and also for maintaining the strength of the cap.

As seen in FIG. 2b, the ribs 22 are equally divided with respect to the cap axis and are arranged at equal intervals.

Figures 3a and 3b show a cross-sectional view and a plan view of an inlet corresponding to the cap 21 of the above-described structure.

In FIG. 3a, 25 is a male thread provided on the outer periphery of the opening of the injection port, and the female thread of the cap 21 is screwed into 22 to seal the injection port. Reference numeral 26 denotes an opening inner slope ring, the inner diameter of which is slightly smaller than the outer diameter of the inner lid 24. Note that the entire injection port is integrally molded from hard synthetic resin.

Further, the flange portion extending to the outer periphery of the lower portion is a connecting portion when joining the inlet to the container. When the cap 21 is loosened or screwed on from the inlet, the inlet is generally connected to a container, and that container is engaged with a conveyor or filling device, so that the cap 21 is not loosened or screwed on. It can counteract the rotational torque applied to the inlet when it is installed, and prevent the inlet from rotating together.

[Problems to be solved by the invention] Therefore, the present invention uses an air motor that uses compressed air as the power source for tightening and loosening the cap 21, thereby achieving small size, light weight, simple structure, and stable performance. It is an object of the present invention to provide a screw capper in a filling device with characteristics that are easy to adjust.

(b) Structure of the invention [Means for solving the problems] The invention consists of the following constituent elements in order to achieve the above purpose.

A double-acting piston that can reciprocate in the axial direction but is restricted from co-rotating is fitted into the center of the cylinder, and a rotating shaft is provided coaxially on the central axis of the piston via a bearing. , one end of the coax has a claw on a part of its circumferential surface that fits into a rib protruding from the outer circumference of the cap to transmit rotational torque to the cap, and a rubber for holding the cap on the inside of the opening edge of the lower end. cap holder and cap holder,
The cap stoppers are respectively attached concentrically, while the other end of the rotating shaft is connected to the output shaft of an air motor, which is provided on the other side of the reciprocating piston and reciprocates with the piston relative to the cylinder, via a reduction mechanism. Skrill caps are characterized by being connected.

[Operation] Compressed air is introduced into the air cylinder and above the piston to lower the reciprocating piston, the rotating shaft attached to the piston, and the cap holder to a certain position, and the cap holder carried directly below the cap holder is lowered to a certain position. The holder is fitted onto the cap of the container.

At this time, the stroke of the reciprocating piston is designed so that the holder descends at least to a height that allows the ends of the claws provided on the circumferential surface of the cap holder to engage with the ribs provided on the circumferential surface of the cap.

When compressed air for driving the air motor is supplied to the motor and the motor is rotated, the cap holder is rotated counterclockwise via the deceleration mechanism, the claws engage the ribs of the cap and transmit the rotational torque of the holder to the cap. As a result of rotating the cap to the left and unscrewing it from the injection port of the container, the cap rises and enters the holder while pushing up the presser foot of the holder with its upper surface, and the upper circumferential surface is held by the holding rubber. After being pressed and released from the injection port, it is held by a cap holder.

When the lifting movement of the cap holder reaches a certain limit, the limit switch operates and switches the electromagnetic air valve circuit to open the space above the piston to the outside, while introducing compressed air below the piston to raise the cap holder. Cut off the supply of compressed air to the air motor and stop the rotation of the holder. At this time, the cap is pushed down by about 2 mm relative to the holder due to spring pressure, but the cap does not separate from the holding rubber.

When a predetermined amount of content is filled into the container through the injection port, compressed air is again introduced into the air above the piston to slide the reciprocating piston to the lower limit, and the cap held in the cap holder is injected. Cover the entrance. At this time, the cap is 2
Since it protrudes downward by approximately 1.5 mm, the female thread on the cap engages with the male thread on the outer periphery of the inlet. Compressed air for driving the motor is supplied from the opposite side to the air motor. When the cap is reversed, the cap screws into the injection port, escapes the restriction of the holding rubber of the holder, and advances toward the injection port.
Of course, the claws provided on the circumference of the holder engage the ribs of the cap and transmit the rotational torque of the holder to the cap, so when the cap is fully screwed into the inlet and cannot be rotated any further, The magnitude of the tightening torque ultimately depends on the magnitude of the driving force of the air motor. Therefore, if the capacity of the air motor is kept constant, the tightening torque can be adjusted by adjusting the pressure or supply amount of compressed air for driving the air motor.

The cap moves downward as it is screwed into the injection port, causing mutual slippage between the cap and the holding rubber of the holder, but even in this case, the claws of the holder slide against the ribs on the circumference of the cap. They are engaged and transmit rotational torque, and the relationship remains intact even when the cap is fully screwed into the inlet.

When the cap has been tightened to the inlet, that is, when the rotation of the cap holder has stopped, the microswitch detects this and cuts off the supply of compressed air for driving the air motor, and at the same time opens the space above the piston to the outside air. , compressed air is introduced into the lower space to raise the piston, and the cap holder rises accordingly, releasing the holder from the cap.

In this way, the filled and closed container is moved from the lower position of the screw cap to another location, and a new container with a cap is brought in and stopped at the same position.

By repeating the steps described above, the cap is unscrewed and screwed onto one container.

[Embodiment] Fig. 1 shows a side cross-sectional view of one embodiment of the present invention, in which 1 denotes a compressed air supply/discharge port for driving an air motor, and these air passages are either supply holes or discharge holes to change the rotation direction of the air motor. The air passages 1 are connected to an air motor 16 through an upper piston rod 6 connected to one side of a piston 20. In the internal cavity of the piston rod 6, an air motor 16 and a planetary gear reduction mechanism 5 are assembled in order from the top, and the output shaft of the motor 16 is connected to the sun gear of the planetary gear mechanism, and the internal gear 4 constituting the mechanism is molded integrally with the piston rod 6. In the end, the planetary support frame of the planetary gear mechanism becomes the output shaft, and is connected to the upper end of the lower rotating shaft 10 by a shaft coupling. The rod 6 of the assembly of the air motor 16 forms a rotor case. The reciprocating piston 20, upper piston rod 6, and lower piston rod 9 as a whole are fitted into the cylinder center section 3, cylinder upper section 7, and cylinder lower section 8 so as to be able to slide vertically, and the distance that the piston 20 reciprocates within the space formed within the cylinder center section 3 is the vertical stroke of the rod 6.

In order to prevent the piston 20 and rods 7 and 9 from rotating in reverse due to the reaction force of the rotational torque received when the cap is tightened, a key and a keyway are provided between the cylinder 8 and the rod 9 to prevent rotation.

Introduction holes 19 for introducing compressed air into the cylinders are provided on both sides of the reciprocating piston 20, and the figure shows a state in which compressed air is supplied to the lower side of the piston 20, and the piston 20 is It is shown stopped at the upper limit position.
When compressed air is introduced above the piston 20, the piston 20 and the cap holder 11, etc., move downward by the stroke length of the piston 20 as compared to the illustrated position.

Reference numeral 10 denotes a rotating shaft provided concentrically with the piston rod 9, which is supported by the rod 9 via bearings, and its upper end is connected to the planetary gear support frame using a shaft joint, and the shaft is connected to the planetary gear support frame by a nut 2. It is fixed to the inner ring. The lower end of the rotating shaft 10 protrudes beyond the lower end surface of the piston rod 9, and a cap holder board 12 is fitted and fixed there, while the upper end edge of a cylindrical cap holder is fixed to the periphery of the board 12. A soft cap-retaining rubber 27 is wound and fixed inside the lower edge of the holder, and its inner diameter is slightly smaller than the cap's outer diameter. The cap is pushed into or pulled out from the inner periphery of the holding rubber 27, but the weight of the cap itself and the addition of minute vibrations cause the cap to break free from the holding rubber 2.
7 so that it cannot be pulled out.

Further, a sliding groove is provided by cutting out a part of the peripheral wall of the cylindrical holder 11 along the generatrix direction, and occupies a position in the sliding groove that can be engaged with a rib provided on the outer periphery of the cap from the lateral side in the circumferential direction, and A claw 18 movable upward and downward is fitted, and a presser spring 17 is installed between the upper surface of the claw and the holder base plate 12.
is configured so that it always occupies a fixed downward position with respect to the holder 11.

Inside the cap holder 11, there is also a cap holder 14 which is fitted onto the lower end of the extension of the rotating shaft 10 and is movable upward and downward.
The presser foot is always urged downward by a cap presser spring 13. 15
is a stopper, which also serves as a guide for the cap presser foot 14.

The screwdriver consisting of the configuration explained in detail above.
The operating order or method of use of the capper is the same as explained in the "Function" section above, so it will not be explained again.

However, the planetary gear mechanism described only as a reduction mechanism in the same column has two stages in this embodiment, and the output shaft of the air motor 16 is connected to the sun gear of the first stage planetary gear mechanism, and this is the input shaft. On the other hand, the internal gear 4 is commonly formed integrally with the piston rod 6, and the supporting frame of the planetary gear rolling therebetween is connected to the sun gear of the second stage planetary gear mechanism. The support frame of the planetary gear provided between the sun gear and the internal gear serves as the input of the gear mechanism, and serves as the output shaft of these reduction mechanisms.
Connected to 0. By adopting such a mechanism, we were able to realize a compact gear mechanism with low vibration and high reduction ratio.In addition, since the input shaft and output shaft are on the same line, the layout of each mechanism can be easily laid out. It was done.

(c) Effects of the invention By adopting the above-mentioned mechanism, this invention
It has a simpler cylindrical structure than conventional devices, is small and lightweight, can be driven only by air pressure, and can be screwed on and off from the container. In addition, it is possible to provide a screw capper that is easy to adjust and maintain.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of an embodiment of the screw capper of the present invention, and FIG. 2 shows an example of a screw cap handled by the capper, in which a is a sectional view and b is a plan view. FIG. 3 shows an inlet member into which the screw cap is screwed, and FIG. 3A is a cross-sectional view, and FIG. 3B is a plan view. DESCRIPTION OF SYMBOLS 1... Compressed air inlet for motor drive, 2... Tightening nut for fixing the rotating shaft, 3, 7 and 8... Cylinder, 4... Internal gear, 5... Planetary gear reduction mechanism, 6 and 9... ... Piston rod, 10 ... Rotating shaft, 11 ... Cap holder, 12 ... Holder board, 13 ... Cap presser, 14 ...
Cap holder, 15...Stopper, 16...Air motor, 17...Claw presser, 18...Claw, 1
9... Compression inlet for driving the piston, 20... Piston, 27... Rubber for holding the cap.

Claims (1)

[Scope of utility model registration request] A double-acting piston that can reciprocate in the axial direction but is restricted from co-rotating is fitted into the center of the cylinder, and a rotating shaft is provided coaxially on the central axis of the piston via a bearing. , one end of the coax has a claw on a part of its circumferential surface that fits into a rib protruding from the outer circumference of the cap to transmit rotational torque to the cap, and a rubber for holding the cap on the inside of the opening edge of the lower end. cap holder and cap holder,
The cap stoppers are respectively attached concentrically, while the other end of the rotating shaft is connected to the output shaft of an air motor, which is provided on the other side of the reciprocating piston and reciprocates with the piston relative to the cylinder, via a reduction mechanism. Skrill caps are characterized by being connected.