JPH0118940Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a tube exhaust device in a tube manufacturing process.

Generally, a large number of tube exhaust devices for exhausting the air inside the tube are installed around the periphery of a rotating turret or spider, and as the turret rotates, a large number of tubes are sequentially evacuated to a high degree of vacuum. ing. By the way, tube bulbs, such as fluorescent tubes, are particularly prone to cracking or cracking due to insufficient vacuum proof strength.Moreover, when a tube cracks like this suddenly, the atmosphere can cause Since it flows into the exhaust system and flows back to other unbroken tubes, it was necessary to install a shutoff valve between the tube and the vacuum exhaust system.

However, conventionally, this type of shutoff valve is only opened and closed according to the result of detecting the backflow of atmospheric air using a detection device. had to be installed in each exhaust system, which caused the problem of being extremely uneconomical.

The purpose of this invention is to provide a tube exhaust device that can automatically shut off the exhaust passage and intake passage in the event of a crack in the tube, and that can control the communication and disconnection of these two passages simply by applying different magnetic fields using electromagnets. It is to provide.

The tube exhaust device according to the present invention includes an exhaust passage leading to the exhaust pipe of the tube and an intake passage leading to a vacuum source, which are connected to each other via a valve chamber and whose open ends on the valve chamber side are arranged facing each other. , a valve seat formed at the opening end of the intake passage on the valve chamber side; a valve body disposed within the valve chamber so as to be able to engage with the valve seat and pressed by a spring in a direction away from the valve seat; a movable iron core disposed to be movable relative to the valve body in substantially the same direction as the movement direction of the valve body and capable of moving the valve body into engagement with the valve seat by the action of magnetic force; A magnet capable of attracting and holding the movable iron core in a state where the body engages with the valve seat, and an electromagnet that applies magnetic force to the movable iron core to move the movable iron core,
The valve body is configured to engage with the valve seat to cut off communication between the exhaust passage and the intake passage when the pressure in the exhaust passage increases.

In the above configuration, when a unidirectional magnetic field is applied to the movable core by an electromagnet to move the movable core, the movable core moves the valve body, and the valve body engages with the valve seat, thereby preventing communication between the exhaust passage and the intake passage. The movable core is attracted and held by a magnet to maintain that state.
Next, when a magnetic field in the opposite direction is applied to the movable iron core by an electromagnet, the attraction and holding force by the magnet is released, and the valve body is pushed away from the valve seat by the action of the spring, thereby communicating the exhaust passage and the intake passage. When the pressure in the exhaust passage suddenly increases, the valve body is pushed by the pressure and engages with the valve seat, cutting off communication between the exhaust passage and the intake passage.

An embodiment of the tube exhaust device according to the present invention will be described below with reference to the drawings.

The tube exhaust device of this embodiment is constructed by attaching a shutoff valve 3 directly to the open end of an exhaust passage provided in the device body 2.

The main body 2 has an insertion hole 20 into which the exhaust pipe P of the bulb V is inserted, and an exhaust passage 21 communicating with the insertion hole 20.
is formed. An annular seal member is provided at the opening of the insertion hole 20 to seal the inside of the insertion hole from the outside.
That is, the mouth rubber 22 is attached by the cover 23, and the exhaust pipe P is inserted into the insertion hole 20 through the mouth rubber.
inserted inside.

The shutoff valve 3 is fixed to the device body 2 so as to cover the open end of the exhaust passage 21, and has a valve body 30 formed with an axial through hole 31 coaxial with the exhaust passage.
and a valve body 33 movably disposed within a valve chamber 32 defined by the device body 2 and the valve body 30.
The valve body 3 is inserted into the through hole 31 and has a valve body 3 at the lower end.
3 is fixed and a large diameter portion 35 is formed at the upper end of the valve stem 34, and the through hole 3 is arranged at the upper part of the valve body.
An annular magnet 37 is fixed by a cover 36 made of magnetically expelling material and fitted into the large-diameter opening of 1, and a ring-shaped magnet 37 is movably mounted inside the cover and is always attached to the valve body side (in the direction away from the magnet 37) by a spring 39. ) and a tubular movable iron core 38 which is pressed against the core.

An exhaust passage 2 is provided at the open end of the through hole 31 on the valve chamber 32 side.
A valve seat 41 faces the opening end 24 of 1 and the valve body.
A valve seat ring 40 forming a valve seat ring 40 is fitted. The valve body 33 is biased toward the open end 24 of the exhaust passage 21 by the spring 42, that is, in a direction away from the valve seat 41, and is stopped in a state where the valve body 33 is approximately in the center of the valve chamber. At this time, the movable iron core 38
The large diameter portion 35 of the valve stem is pressed against the annular spacer 44 which functions as a stopper, and the large diameter portion 35 of the valve stem is in contact with the inner peripheral flange 38a of the movable iron core.

A curved pressure receiving surface 33a is formed on the surface of the valve body 33 on the side of the open end 24 to easily receive the force of the air flow from the exhaust passage.

The through hole 31 is connected to a vacuum source (not shown) via an intake passage 45. A seal 46 prevents air from flowing into the valve chamber from between the device main body and the valve body, and a seal 47 prevents air from flowing into the through hole 31 from between the valve body and the cover.

In the tube exhaust device configured as described above, the exhaust pipe P of the tube V held in a known tube holder or the like is inserted into the insertion hole 20 through the mouth rubber of the exhaust device 1. By connecting the intake passage 45 to a vacuum source, the bulb V is exhausted through the exhaust pipe P exhaust passage 21 and the intake passage. At this time, since air does not suddenly act on the pressure receiving surface 33a of the valve body 33, the valve body 33 maintains almost the state shown in the figure, and therefore the valve body 33 and the valve seat 41 are separated from each other. ing.

Even though vacuum evacuation was performed for a specified period of time,
When the degree of vacuum in the exhaust system does not improve due to cracks in the tube V, etc., this is detected by a vacuum detection device (not shown) installed in a part of the intake passage 45, and the electromagnet 5 is activated. The iron core 38 is sucked. Therefore, the large diameter portion 35 of the valve stem 34 engages with the iron core and is pulled up, and the valve body 33 comes into contact with the valve seat 41, cutting off communication between the bulb exhaust pipe P and the vacuum intake passage 45. . Therefore, the vacuum exhaust passage 4
5 is maintained at a high vacuum, and does not adversely affect other exhaust devices connected to the vacuum intake passage.

Moreover, the iron core 38 that has been attracted by the electromagnet 5 and moved to the center of the annular magnet 37 continues to be attracted to the magnet 3.
Even if the electromagnet 5 is demagnetized or the exhaust device 1 is moved and separated from the electromagnet provided in the fixed position, the valve body 3 will still be attracted and held by the valve body 7.
3 and the valve seat 41 remain engaged, and the exhaust passage and intake passage are closed. Therefore, tubes with defects such as cracks are not further ejected. If there is no air leakage in the tube V, the vacuum will continue to be evacuated with the valve open as shown in the figure.

In order to release the closed valve when the iron core 38 is attracted to the magnet 37, by creating a magnetic field in the opposite direction to that of the electromagnet using another electromagnet,
Alternatively, by forming a magnetic field that cancels the holding force of the movable core of the magnet, the attractive force of the magnet 37 is temporarily reduced, and the elastic force of the spring 39 releases (the core). Bye.

On the other hand, if the bulb V suddenly breaks, the atmosphere will flow from the open end 24 of the exhaust passage to the pressure receiving surface 3 of the valve body 33.
3a, and against the reaction force of the spring 42, the valve body 3
3 is pushed up by the reaction of the airflow to engage the valve body and the valve seat 41. At this time, the iron core 38 does not move, and only the valve stem 34 moves. However, since atmospheric pressure acts on the pressure receiving surface 33a of the valve body 33 once closed, and vacuum pressure (back pressure) acts on the back surface thereof, the valve body 33 does not return to its original state. That is, the broken tube will not be evacuated again.

In order to open the valve that has been closed due to the inrush of atmospheric pressure, that is, to bring the valve body 33 into the state shown, temporary air is introduced into the vacuum intake passage 45 via a switching valve (not shown). Just introduce it.

Incidentally, the exhaust pipe P of the bulb which has been completely evacuated is fused and sealed by known means.

As is clear from the above explanation, according to the tube exhaust device of the present invention, an electromagnet and a vacuum detection device are combined into one
By simply installing it in one or two locations, even if the tube is damaged, the vacuum intake system can be maintained at a high vacuum and can be operated without affecting other tube exhaust devices, and the manufacturing cost of the device can be reduced. can be reduced.

[Brief explanation of the drawing]

The figure is a sectional view of a tube exhaust device according to the present invention. 1: Tube exhaust device, 2: Device body, 20: Insertion hole, 21: Exhaust passage, 24: Open end, 3: Shutoff valve, 30: Valve body, 32: Valve chamber, 33: Valve body, 3
4: Valve stem, 36: Cover, 37: Magnet, 41: Valve seat, 42: Spring, 5: Electromagnet.

Claims (1)

[Scope of utility model registration request] An exhaust passage leading to an exhaust pipe of a tube and an intake passage leading to a vacuum source, which are connected to each other via a valve chamber and whose opening ends on the valve chamber side face each other, and an intake passage leading to a vacuum source, and an opening of the intake passage on the valve chamber side. a valve seat formed at an end; a valve body disposed in the valve chamber so as to be able to engage with the valve seat; and a valve body that is biased by a spring in a direction away from the valve seat; and a valve body that is substantially in the same direction as the movement direction of the valve body. a movable iron core disposed to be movable relative to the valve body in a direction and capable of moving the valve body into a state of engagement with the valve seat by the action of a magnetic force; and the valve body engages with the valve seat. A magnet capable of attracting and holding the movable iron core in a state, and an electromagnet that applies a magnetic force to the movable iron core to move the movable iron core, and when the pressure in the exhaust passage increases, the valve body closes to the valve seat. A tube exhaust device characterized in that it is configured to engage with the exhaust passageway and cut off communication between the exhaust passageway and the intake passageway.