JPS6139841Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is an improvement of the boost pressure control device that operates a bypass valve to prevent the exhaust gas pressure from rising above a certain level in order to prevent overspeed and boost pressure when the engine rotates at high speed. It's about structure.

Conventionally, this type of boost pressure control device connects the engine to the exhaust pipe, and when the boost pressure is below the set value, the valve is fully opened and the entire amount of exhaust gas flows to the turbine. However, when the boost pressure exceeds the set boost pressure, the boost pressure increases. Accordingly, a part of the exhaust gas is released by the boost pressure control device to prevent the boost pressure from increasing.

By the way, this type of conventional boost pressure control device has
As shown in Fig. 1, it has a positive pressure chamber A and an atmospheric chamber B, and these two chambers are separated by a diaphragm 6, but in order to prevent dust from entering from the atmospheric chamber B, a case 3 and a rod are connected. A gasket 13 is inserted between the holes 9 and 9 through a washer 14. This packing 13 is fixed by a spring 11 via a washer 14 and a spring holder 10. When inserting this packing 13, the washer 14 is inserted and the packing 13 is moved in the thrust direction via the spring holder 10. The work of fixing it was not easy to do, the number of parts increased, and there were problems in terms of cost.

This invention was devised to eliminate the drawbacks of the conventional device described above, and an embodiment of this invention shown in FIGS. 2 and 3 will be described below. In the figure, 1 is a bracket for mounting the boost pressure control device, 2 is its mounting bolt, and 3 is the above-mentioned bracket 1.
3a is a catch for fixing the diaphragm 6 by caulking, 3b is a catch 4 of the positive pressure case 4.
The holding part 3c that holds ``a'' is an atmospheric passage hole part through which a rod 9 (to be described later) is inserted. 5 is a positive pressure introducing nipple into which positive pressure is introduced, 6 is a diaphragm, 7 is a positive pressure side holder, 8 is an atmosphere side holder, 8a is a stopper, 8b is the tip of the stopper 8a, L is the operating stroke width of this device , 9 is a rod, 9a is a rod hole connected to a valve (not shown), 10 is a spring holder, 10a is a hole in this holder 10, 10
b is the seat of the spring 11 provided on the outer periphery of one end of this holder 10, 10c is the holding piece of the packing 13 provided on the inner periphery of one end of the holder 10, _L1 is a distance slightly longer than the above-mentioned operating stroke L, and 12 is the It is an atmospheric cave.

Next, the operation of such a component device will be explained. First, in a desired engine operating state, by operating a positive pressure control means (not shown) that controls the positive pressure to the positive pressure introduction nipple 5 in accordance with the engine operating state.
When positive intake pressure of the engine is introduced into the positive pressure case 4 from the positive pressure introduction nipple 5, this positive pressure acts on the diaphragm 6, and the diaphragm 6 acts on the spring 11.
The rod 9 is moved in the direction of the arrow P against the urging force of , and a part of the exhaust gas in the exhaust pipe (not shown) is released, thereby adjusting the overpressure in the suction pipe. On the other hand, when the positive pressure acting on the diaphragm 6 decreases, the rod 9 moves in the opposite direction due to the biasing force of the spring 11, closing the exhaust pipe valve and cutting off the flow of exhaust gas.

By the way, in the structure as described above, when the suction pipe of the engine reaches supercharging pressure, positive pressure is introduced from the suction hole provided in the suction pipe to the introduction nipple 5 of the supercharging pressure control device, The rod 9 operates via the diaphragm 6, and the valve provided in the exhaust pipe is opened, and part of the exhaust gas is released to the outside, controlling the supercharging pressure of the suction pipe. The device uses an atmosphere passage hole 3c in the case 3 and a gasket 13 to prevent dust from entering from the atmosphere side. Therefore, in the present invention, the spring holder 10 is integrally provided with a plurality of protruding presser pieces 10c for preventing the movement of the seal 13, and the seal 13 is held by the presser pieces 10c. The washer 14 that was used can be removed.

In the above device, even if dust enters through the atmosphere passage hole 3c of the case 3 and the gasket 13,
The spring holder 10 is provided with an atmospheric cavity 12, and the dust that enters accumulates in this cavity 12 and must pass through the hole 10a of the spring holder 10 before entering the diaphragm chamber 6. , virtually impenetrable. Also, the stroke in which supercharging pressure is introduced from the nipple 5 and displaces the rod 9 in the direction of arrow P via the diaphragm 6 is up to L, but even if the diaphragm 6 is displaced by L, it does not come into contact with the spring holder 10. Therefore, L<L ₁ . The diaphragm 6 operates in the radial direction using the valve connection hole 9a as a fulcrum, but in order to allow the diaphragm 6 to operate normally, the spring holder 10 is deep drawn and the hole 10a is placed on the diaphragm side. Even if it does not operate normally and is displaced in the radial direction, the displacement operation is regulated by coming into contact with this hole 10a. Also, spring holder hole 1
As a countermeasure against wear of 0a, treatments such as hardening are performed.

As described above, according to this invention, the movement of the packing in the thrust direction can be prevented with a simple structure without using washers, and the intrusion of dust into the atmospheric chamber of the case can be effectively prevented. Furthermore, even if a force is applied to displace the diaphragm in the radial direction, the amount of displacement is minutely controlled, and wear due to contact between the holder for stroke control of the rod and the case is prevented.

[Brief explanation of the drawing]

Figure 1 is a sectional view showing a conventional boost pressure control device.
Figure 2 is a sectional view showing one embodiment of this invention;
The figure is a perspective view of the main part. In the figure, 3 is a case, 3c is an atmosphere passage hole, 6 is a diaphragm, 8 is an atmosphere side holder, 8a is a stopper, 9 is a rod, 10 is a spring holder, 10
b is a spring seat, 10c is a holding piece, 11 is a spring, and 13 is a gasket. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A diaphragm separates the inside of the case into a positive pressure chamber into which positive pressure is introduced and an atmospheric chamber, and a gasket is installed in the atmospheric passage hole provided on the atmospheric chamber side of the case. The rod has a rod that is inserted into the atmospheric chamber from the outside of the case and whose tip is connected to the diaphragm, and has an atmospheric side holder for controlling the stroke width of the rod and urges the diaphragm toward the positive pressure chamber. 1. A supercharging pressure control device comprising a spring holder having a seat for a spring, characterized in that a presser piece of the packing is integrally protruded from an inner peripheral portion of the seat of the spring holder. (2) The supercharging pressure control device according to claim 1, wherein the packing presser piece is formed in the shape of a plurality of protrusions.