JPS628109Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a pneumatic operating device for a shroud breaker, and more specifically, the present invention relates to a so-called two-stage pneumatic operating device that changes the closing operation force in response to changes in the closing load of the shear breaker. This invention relates to a pneumatic device that eliminates motion.

In general, in a shear breaker in which the shear cutting operation of the sheath section is performed by a shear cutting spring, and the closing operation is performed by compressed air, the closing load is as shown in Figure 1. Since it is necessary to store the force of the blade spring and to store the force of the pressure contact spring added to the blade spring after the contact touch, the curve A becomes a sloped step-like curve. In FIG. 1, the horizontal axis represents the stroke S, and the vertical axis represents the load F.

However, the closing operating force F of the conventional air operating device
As shown in FIG. 2, is set large from the start of making so as to be able to cope with the making load at the time of completion of making (stroke end). In FIG. 2, the horizontal axis shows the stroke S, and the vertical axis shows the closing operation force F'. Here, just before the contact is touched, the curve B of the closing operation force F is
Since the shaded area C surrounded by the curve A of the input load F mentioned above is added as extra input operation energy compared to the energy required to obtain the predetermined input speed, an energy absorption device such as a damper is provided. This prevents the closing speed from becoming too high due to excess closing operation energy, and also absorbs the impact force at the contact point. As a result, the structure of the breaker becomes complicated and costs increase.

Furthermore, in order to remove excess operating energy absorbed by an energy absorbing device such as a damper, an air operating device has been proposed that throttles the supply of operating air supplied into the cylinder.
Since it takes time for the pressure inside the cylinder to rise when a contact is touched, a so-called two-stage motion occurs in which the operation of the air operating device temporarily stops, resulting in problems such as an excessively long input time.

The present invention was developed in view of the above-mentioned problems, and its purpose is to remove excess closing operation force by changing the closing operation force in accordance with the input load, and to absorb energy such as a damper. The object of the present invention is to provide an air operating device that does not require any equipment or disconnects.

Embodiments of the present invention will be described in detail below with reference to the drawings.

3 to 5 are cross-sectional explanatory views of the pneumatic operating device 1 according to the present invention in a shrunken state,
This air operating device 1 includes a bow spring (not shown).
The shear section that is operated by the shear cutter (not shown)
are brought into contact with each other by using compressed air to store energy in the bow spring, and furthermore, the pressure contact spring (not shown) is brought into pressure contact while being stored in power to perform the closing operation.

A cylinder body 2 of the air operating device 1 is provided with an air chamber 3 having a relatively large capacity. The air chamber 3 is used to supply and exhaust high-pressure compressed air when inserting the shingle cutting section or during the shear cutting operation, and has an air supply port 4 in the bottom wall and an exhaust port 5 in the side wall. It is perforated. Note that although the air supply port 4 is not shown,
It is connected via a switching valve to an air tank that is constantly filled with high-pressure compressed air by a compressor.

Further, the exhaust port 5 is provided so as to be freely closable by an exhaust valve 7 which is opened and closed by an exhaust valve mechanism 6. That is, the cylinder body 2 has an exhaust port 5.
A main body block 9 of the exhaust valve operating mechanism 6, which communicates with the main body block 9 and has an exhaust hole 8 opening outward, is fixed via a fastener 10 such as a bolt, and a piston formed in the main body block 9 Room 1
An exhaust valve piston 13 is slidably connected to the exhaust valve 7 through a connecting rod 12 that is slidably inserted into the main body block 9.

The exhaust valve piston 13 is moved to open the exhaust valve 7 by compressed air supplied from the air tank (not shown) through a port 15 formed in a lid member 14 that covers the piston chamber 11. Also, the bottom of the piston chamber 11 and the exhaust valve piston 1
3, the exhaust valve 7 is moved back to close by a return spring 16 mounted between the exhaust valve 7 and the exhaust valve 7.

A first piston chamber 17 is formed in the cylinder body 2 so as to be connected to the air chamber 3.
This first piston chamber 1 is connected to the piston chamber 17.
A second piston chamber 18 having a diameter larger than 7 is bored and opens upward in FIG. A cylinder cap 19 is slidably inserted into the second piston chamber 18, and a large-diameter portion 21a of an operating piston 21 having an operating rod 20 connected to a shingle portion is slidably fitted. ing. Note 19a
is a hole drilled in the cylinder cap 19.

The operation piston 21 includes the first
Small diameter portion 2 slidably fitted into piston chamber 17
1b is integrally formed. A plurality of communication holes 24 are provided in the lower part of the small diameter portion 21b of the operating piston 21 in the circumferential direction, and a first piston chamber 1 of the small diameter portion 21b is provided.
The length of the fitting with respect to 7 is set to be slightly longer than the length of movement of the operating piston 21 from the start of the closing operation until the contact touch of the mustard cut portion is made. Therefore, the small diameter portion 21b of the operating piston 21 that has been moved for the closing operation is maintained in engagement with the first piston chamber 17 even during the contact touch, and the communication hole 24 is maintained in the second piston chamber 17.
It is located at a higher position than the bottom 18a of the piston chamber 18, and is connected to the first piston chamber 17 through the communication hole 24.
and the second piston chamber 18 are communicated with each other.

Further, a recess 22 is formed inside the small diameter portion 21b of the operating piston 21.

In order to insert the shingle cut portion with the above configuration, first, the exhaust valve 7 is operated by the exhaust valve mechanism 6 to close the exhaust port 5. Next, high-pressure compressed air is caused to flow into the air chamber 3 from the air tank through the air supply port 4. When the pressure inside the air chamber 3 increases due to the inflow of compressed air, the operating piston 21 moves up while compressing the blade spring, and before the blade contact is touched, the operation piston 21 moves as shown in FIG. The communication hole 24 provided in the small diameter portion 21b of the operating piston 21 is slightly elevated above the bottom portion 18a of the second piston chamber 18.

Therefore, the air chamber 3 is
The compressed air inside also flows into the second piston chamber 18,
Since it also acts on the large diameter portion 21a of the operating piston 21, the pressure receiving area increases, and at first glance, the increase in internal volume causes a decrease in internal pressure, but the pressure in the air chamber 3 increases as its volume increases. Therefore, the air chamber 3 is expanded to cover the increase in internal volume.
Since the volume is formed, the operation piston 21
The input operating force of is rapidly increased.

The operation piston 21, which has increased the closing operation force due to the increase in the pressure receiving area, moves up while compressing the pressure contact spring together with the shoulder breakage spring, and when it reaches the position shown in Fig. 5, the breakage portion is closed by the pressure contact spring. The closing operation is completed when the connectors are pressed into contact with each other.

In the above configuration, a slight gap X occurs between the small diameter portion 21b of the operating piston 21 and the first piston chamber 17, but it is impossible in manufacturing to reduce this gap to zero. However, due to the existence of this gap, the compressed air in the air chamber 3 passes through the gap X and flows into the second piston chamber 18, pushing the large diameter portion 21a. The change did not occur suddenly, and even with the above-described configuration, it could not necessarily be said to be perfect in terms of preventing two-step motion.

The present invention improves the above-mentioned drawbacks, and will now be explained with reference to the above-mentioned drawings. That is, in the present invention, the cylinder body 2 is provided with a bypass 23.
The lower end 23a is provided with an air chamber 3.
It is connected to the air supply port 4 in front of the , and its upper end 23b is connected to the air supply port 4 in front of the
Small diameter portion 21b of operating piston 21 rising
It is provided so as to be able to communicate with the first piston chamber 17 at a height position opened by the lower end of the piston chamber 17 . Furthermore, in order to prevent compressed air from flowing into the second piston chamber 18 from the gap between the small diameter portion 21b and the first piston chamber 17,
7 and the upper end 23b of the bypass 23
Seal rings 25 and 26 such as O-rings are provided at the lower part of the inner circumferential wall located below.

Therefore, according to the above structure, there is no risk of compressed air flowing into the second piston chamber 18 from the gap due to the seal rings 25 and 26 during the closing operation, and the upper end 23b of the bypass 23 is not operated until just before the contact touch. Piston 21
The operating piston 21 is closed by the small diameter portion 21b of the
The force pushing up the air chamber 3 is generated from the air supply port 4 of a predetermined cross section.
However, since the upper end 23b of the bypass 23 is opened just before the contact touch, the compressed air also flows into the first piston chamber 17 from here, and the air chamber 3 and the first piston chamber 1
Since the cross-sectional area of the inlet of the compressed air flowing into 7 is expanded and the flow rate is increased accordingly, the operating piston 21 can rise rapidly, and the large diameter portion 21a
Coupled with the improvement in the closing operation force due to the increase in the pressure-receiving area, the effect of preventing two-stage motion becomes more reliable.

As explained above, according to the air operating device according to the present invention, the operating piston rises to a predetermined height position immediately before the contact touch of the sheath section, so that the compressed air in the first piston chamber is transferred to the second piston chamber. Since it flows into the piston chamber, it is possible to increase the closing operation force in response to an increase in the closing load on the shear breakage, and it is also possible to respond to changes in the closing load that increase due to pressure springs, etc. after contact is made. This has the excellent effect that the charging operation does not become a so-called two-stage motion. In particular, in the present invention, the upper end of the bypass branching from the air supply port before the air chamber is closed by the small diameter part of the operating piston, and the upper end is opened just before the contact touch, and from here the first Since compressed air flows into the piston chamber, the increase rate of the input operation force by the operating piston during contact touch is improved, and the effect of preventing the two-step motion is further ensured.

[Brief explanation of the drawing]

Figure 1 is an explanatory diagram showing the change in the closing load of a general breaker, and Figure 2 shows the relationship between the closing load of a typical breaker and the closing operating force of a conventional pneumatic operating device. Explanatory drawings, FIGS. 3 to 5 are cross-sectional explanatory views of the air operating device according to the present invention, where FIG. 3 shows the state when the shield is disconnected, FIG. 4 shows the state during the closing operation process, and FIG. This shows the status at the time of completion. 2... Cylinder body, 3... Air chamber, 4... Air supply port, 17... First piston chamber, 18... Second piston chamber, 20... Operating rod, 21... Operating piston, 21a... Large diameter part, 21b...small diameter part,
23... bypass, 23a... lower end of bypass,
23b... Upper end of the bypass.

Claims (1)

[Claims for Utility Model Registration] An air chamber 3 is formed in the cylinder body 2, and a first piston chamber 17 and a second piston chamber having a larger diameter than the first piston chamber 17 are connected to the air chamber 3. 18, and an operating rod 20 connected to the sheath section in the second piston chamber 18 and the first piston chamber 17.
The large diameter part 21a and the cylindrical small diameter part 21b of the operating piston 21 are fitted respectively, and the small diameter part 2
The first piston chamber 17 and the second piston chamber 18 are configured to communicate with each other through a communication hole 24 provided through the cylinder body 1b, and a bypass 23 is provided in the wall of the cylinder body 2, and an upper end of the bypass 23 is provided in the wall of the cylinder body 2. 23b is opened to the inner circumferential wall of the first piston chamber 17, and the lower end 2
3a is communicated with the air supply port 4, and when the operating piston 21 moves a predetermined stroke in the direction of inserting the cut-off part, the upper end 23b of the bypass 23 connects with the operating piston 2.
1. A pneumatic operating device for an air breaker, characterized in that it is configured to be separated from the lower end of the small diameter portion 21b of the first piston chamber 17 and communicate with the first piston chamber 17.