JPS6149548B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an exhaust brake valve, and particularly to an exhaust brake valve in which an actuator moves the valve forward and backward to open and close an exhaust pipe.

Conventionally, this type of exhaust brake valve usually includes a body housing the valve and an actuator connected to this body, and the piston rod of the actuator is linked to the valve to move the valve forward or backward, thereby controlling the exhaust gas. It opens and closes the pipe. At the connection between the body and the actuator, a seal is installed around the piston rod to prevent exhaust gas from escaping to the outside through the gap between the piston rod and the through hole formed in the body. Although a sealing material is provided, conventionally the sealing material has generally been constructed from a single component, which has caused problems in durability or sealing performance. In other words, if the sealing material is made of a soft material in order to improve sealing performance, the part of the sealing material that contacts the piston rod is likely to be deformed as the piston rod moves back and forth, and the through hole of the piston rod will often It may get caught in the small gap between the piston rod and the piston rod and be damaged. On the other hand, if the seal material is made of a hard material, the sealing performance will be inferior to that of a soft material. However, there was a drawback that the sealing performance was relatively easily lost due to foreign matter getting caught.

In view of these drawbacks, the present invention consists of a sealing material consisting of a soft sealing material in the middle and a hard sealing material on both sides of the sealing material, and achieves good sealing performance mainly by the soft sealing material in the middle. The hard sealing material on both sides prevents the intermediate sealing material from deforming as the piston rod moves back and forth, thereby ensuring a good sealing material over a long period of time.

The present invention will be described below with reference to the illustrated embodiments.
In Figures 1 and 2, 1 has an exhaust passage 2 inside.
The body includes a cylindrical portion 1a with a hole 3 formed therein, and a cylindrical portion 1b with a hole 3 having a rectangular cross section perpendicular to the exhaust passage 2.Both ends of the cylindrical portion 1a are connected to an exhaust pipe (not shown), and The open end of the cylindrical portion 1b is closed by a plate 5 attached to the body 1 with bolts 4. 6 is a conventionally known actuator;
This actuator 6 is connected to the body 1 through a spacer 7 and a bolt 8. At this time, an air passage 9 is formed between the body 1 and the actuator 6 by the spacer 7, and this air passage 9 prevents the high temperature of the exhaust gas from being transmitted to the actuator 6.

The actuator 6 includes a piston 10 and a piston rod 11 connected to the piston 10, and the tip of the piston rod 11 is connected to a guide 13 of the piston rod 11 provided on an end plate 12 forming a part of the outer shell of the actuator 6. It slidably passes through the through hole 14 and the through hole 15 provided in the plate 5, and is located in the hole 3. The guide 13 is fitted into the through hole 14 and guides the piston rod 11 in forward and backward movement. A through hole 15 formed in the plate 5 is formed on a line passing through a connection point between a valve member and a piston rod 11, which will be described later, and along the forward and backward direction of the valve member, with this line as the center. Large diameter portions 16 and 17 of each through hole 14 and 15 are formed on the surfaces of the end plate 12 and plate 5 that face each other, and each large diameter portion 16 and 17 has an outer periphery having a large diameter. A distal end portion of a cylindrical body 18 formed to match the diameter of the diameter portion is fitted. An annular support part 18a is formed in the center of the cylinder 18, and three sets of sealing materials 19 are provided on both sides of the annular support part. Make sure to seal it, and this will prevent it from happening.
Even if the sealing material 9 on the exhaust passage 2 side is damaged by exhaust heat or the like, the other sealing material 19 can prevent exhaust gas from entering the actuator 6.

As shown in FIG. 3, each set of three sealing materials 9 is composed of a relatively hard sealing material 19a placed on both sides and a relatively hard sealing material 19b placed in the middle. , and each set of three sealants 19a, 19b in a natural state.
The total axial length of 19a is ₁ , which is the axial length of the cylindrical body 18.
It is set to be longer than the length ₂ from the end surface of the annular support portion 18a to the open end of the cylindrical body 18. Further, a slit 20 is formed on the outer circumferential surface of the cylinder 8 on the body 1 side, extending in the axial direction from the open end of the cylinder 18 to the annular support portion 18a.

In such a configuration, since both the through holes 14, 15 and the piston rod 11 can be automatically positioned in a straight line by the cylinder 18,
Body 1 compared to conventional equipment using positioning pins
The positioning of the actuator 6 and the actuator 6 can be made easy. In the assembled state of the body 1 and actuator 6, the above-mentioned length is
From the relationship of ₁ and ₂ , each sealing material 19a, 19
b and 19a are compressed and deformed by the difference between their lengths ₁ and ₂ , and in particular, the inner diameter of the middle sealing material 19b, which is relatively small in hardness, is reduced by the compressive deformation to a large extent compared to the other sealing materials 19a. , strongly adheres to the outer peripheral surface of the piston rod 11 and achieves a great sealing effect. On the other hand, the sealing material 19b on both sides of the piston rod 11 is lightly attached to the outer peripheral surface of the piston rod 11, and when the piston rod 11 moves back and forth, the intermediate sealing material 19b
This prevents the piston rod 9b from being displaced and damaged together with the piston rod 11. In addition, each sealing material 19
a, 9b, 19a, since the cylindrical body 18 and the piston rod 11 are in a concentric relationship, the piston rod 11
It is crimped to the outer periphery with even force, and uneven contact will not occur. Furthermore, when the sealing material 19 on the body 1 side is damaged, part of the exhaust gas from inside the body 1 is released into the atmosphere through the slit 20 facing the air passage 9 in the assembled state, and Since there is a sealing material 19 on the actuator 6 side, there is no chance of it entering the actuator 6 and damaging it. Note that the sealing material 9
a and 19b can be manufactured from carbon, asbestos, or the like with different hardnesses.

Of the two chambers 21 and 22 in the actuator 6 divided by the piston 10, a spring 23 is housed in the chamber 22 on the body 1 side to bias the piston 10 in the right direction in FIG. , the chamber 21 is communicated with the atmosphere through a hole 24 formed in the end plate 12 and a filter 25 provided in the hole 24, and the other chamber 22 is communicated with an air pressure source (not shown) through a port 26. ing. Furthermore, one end of the end face plate 1 is inserted into the chamber 21.
2, and the other end of the spring 2 is connected to a holder 27 that is slidably fitted to the outer periphery of the piston rod 11.
There are 8. This spring 28 does not contact the piston 10 and apply elastic force when the piston 10 is positioned at the right sliding end by the spring 23, but as described later, the piston 10 When the piston 10 is moved near the left sliding end, an elastic force is applied to the piston 10 via the holder 27 to strengthen its rightward return force.

Next, a first valve member 29 that covers a small portion of the exhaust passage 2 and a second valve member 30 that covers most of the remaining portion are slidably inserted into the hole 3, and both valve members 29 , 30 as actuator 6
The piston rods 11 are arranged in parallel in the axial direction, and the first valve member 29 is arranged on the actuator 6 side. The first valve member 29 has a rectangular shape, and the second valve member 29 has a rectangular shape.
The valve member 30 has a flat plate with ribs 30a and 30b formed at the periphery and center, respectively, and the opposing surfaces of both valve members 29 and 30 are smooth contact surfaces 3 that can be brought into close contact with each other.
1,32.

Two small diameter portions 11a and 11b are formed at the tip of the piston rod 11 at a predetermined interval, and one of the small diameter portions 11a is formed in the center of the first valve member 29 to match the diameter of the small diameter portion 11a. Fit into U-shaped grooves 29a that are aligned and carved,
This connects the piston rod 11 and the first valve member 29. Also, the other small diameter portion 11
b connects the connecting member 33 and the piston rod 11 by fitting into a U-shaped groove 33a formed in the center part of the connecting member 33 having a rectangular parallelepiped shape in the same manner as the groove 29a. ing. The connecting member 33 is connected to the second valve member 30
The contact surface 32 side rib 30a and the central rib 30b
At the same time, the intermediate portion 11c between the two small diameter portions 11a and 11b is slidable within the notch 30c provided in the rib 30a on the contact surface 32 side. It is slidably penetrated. At this time, the rib 30
The axial length of the piston rod intermediate portion 11c is set to be larger than the wall thickness of the piston rod a, so that the first valve member 29 and the second valve member 30 can be relatively moved by a predetermined distance L. are doing.

Further, a communication hole 34 is formed in the second valve member 30, and an adjuster bolt 35 is screwed into the body 1 to contact the second valve member 30 and adjust the leftward movement end position. However, the exhaust pressure when the exhaust brake is applied can be adjusted to a predetermined value using the communication hole 34 and especially the adjusting bolt 35. Further, in order to detect the exhaust pressure during adjustment, a screw hole 36 for connecting a pressure gauge is screwed into the body 1, and the screw hole 36 is normally closed with a plug 37. Note that the exhaust gas is exhausted in the direction of the arrow in FIG.

With the above configuration, when compressed air is introduced from the air pressure source into the chamber 22 through the port 26 from the open state of the exhaust pipe shown in FIGS. 1 and 2, the piston 10 and the piston rod 11 are It moves to the left against the repulsive force of the spring 23. Then, the first valve member 29 and the connecting member 33 connected to the piston rod 11 immediately start moving to the left as the piston rod 11 moves to the left, but the second valve member 30 is not directly connected to the piston rod 11. Therefore, the valve members 29, 30 do not move until the contact surfaces 31, 32 of the valve members 29, 30 come into contact with each other. When the contact surfaces 31 and 32 come into contact with each other, both the valve members 29 and 30 are integrally moved to the left by the piston rod 11, and when the tip end surface of the second valve member 30 comes into contact with the adjuster bolt 35, the valve members 29 and 30 move to the left. The line is stopped (Figure 4). In this state, the contact surfaces 31 and 32 are in close contact and almost no exhaust gas is allowed to flow through them, and both valve members 29 and 30 are pressed against the bottom of the hole 3 by the exhaust pressure to close the exhaust passage 2. , exhaust braking is performed. At this time, since the piston 10 contacts the holder 27 and bends the spring 28 before moving to its leftward end, a large return force is applied to the piston 10 by the springs 23 and 28.

Next, the piston 10 and the piston rod 11, which discharge the compressed air in the chamber 22, are moved to the right by the above-mentioned large return force, but at the beginning of the right movement, the above-mentioned return force is substantially reduced by the small first valve member. 2
It only needs to be large enough to move 9 to the right, so
The first valve member 29 can be moved to the right with a much smaller return force than when the valve is composed of a single member. Then, the first valve member 29 and the connecting member 33 are connected to the piston rod 1.
When the contact surfaces 31 and 32 of both the valve members 29 and 30 are separated from each other as shown in FIG. Since the pressure difference between the two valve members 29 and 30 becomes smaller, the pressing force for pressing both the valve members 29 and 30 against the bottom surface of the hole 3 becomes smaller. Further, when the connecting member 33 comes into contact with the rib 30a of the second valve member 30, this second valve member 30 is also moved to the right together with the piston rod 11, but at this time, as described above, both valve members 29 , 30 are reduced, it is possible to quickly return both valve members 29, 30 to their original open positions with a small return force.

In the above embodiment, the valve is made up of two valve members 29 and 30, but it goes without saying that a single valve can be used, and the sealing material 19 is not necessarily provided inside the cylindrical body 18. There's no need. Furthermore, in the above embodiment, three sheets of sealing material 19 are used.
a, 19b, and 19a are compressed and deformed in the axial direction so that their inner diameter portions are brought into close contact with the piston rod 11, but if the inner diameter of the sealing material is made smaller than the diameter of the piston rod 11, the sealing material will not necessarily be intentionally deformed. There's no need. Further, the number of sealing materials is not limited to three, and a soft sealing material 19b is placed in the middle, and a hard sealing material 19 is placed on both sides of the soft sealing material 19b.
If a is provided, the intermediate sealing material may be two sheets, for example.

As described above, the present invention is provided with a soft sealing material in the middle and a hard sealing material on both sides. The hard sealing material can prevent damage due to deformation of the intermediate sealing material, and therefore, it is possible to maintain good sealing performance over a long period of time.

[Brief explanation of the drawing]

FIG. 1 is a partial cross-sectional plan view showing an embodiment of the present invention, FIG. 2 is a vertical cross-sectional view taken along the line - in FIG. 1,
Figure 3 is an enlarged vertical cross-sectional view showing the seal portion in Figures 1 and 2 before assembly, Figure 4 is a cross-sectional view of the main part showing the operating state, and Figure 5 is different from Figure 4. FIG. 3 is a cross-sectional view showing an operating state. 1: Body, 2: Exhaust passage, 6: Actuator, 11: Piston rod, 19: Seal material, 1
9a: Hard sealing material, 19b: Soft sealing material, 29, 30: Valve member.

Claims (1)

[Claims] 1. An actuator is connected to a body housing a valve that can move forward and backward between an open position and a closed position of an exhaust passage, and the piston rod of the actuator is interlocked with the valve, and the exhaust gas in the body is caused to flow around the piston rod. An exhaust brake valve equipped with a sealing material for preventing escape to the outside, characterized in that said sealing material is composed of a set of a soft sealing material in the middle and hard sealing materials on both sides thereof. .