JPS6224868Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention mainly relates to a sealing device for a bearing connected to a crankshaft of an internal combustion engine.

The end of the crankshaft of an internal combustion engine protrudes from the crankcase in order to take out the engine's output, but inside the crankcase, lubricating oil that lubricates the moving parts of the engine is scattered in the form of a mist. Furthermore, the combustion gas leaking from the piston ring fills the crankcase, and the inside of the crankcase is normally pressurized.

Furthermore, since the crankshaft deforms under the load of the cylinder's explosion pressure, the end of the crankshaft at the seal portion is constantly swinging around, and the sealing device must be able to withstand such fluctuations.

The crankshaft sealing device must be able to provide a sufficient seal under these conditions, but the conventional gland packing method using cotton, asbestos, etc.
It is not used because it has poor heat resistance and poor sealing properties.

Many of the commonly used ones are labyrinth type, as shown in Figure 1. In Figure 1,
Since the lubricating oil in the crankcase 1 is blown away by the centrifugal force of the oil drain 2, pressure and oil leakage to the shaft end 3 is prevented to some extent, and pressure and oil leakage also occurs in the labyrinth section 4 that follows. The structure is designed to prevent the entry of foreigners. However, in consideration of the fact that the end of the crankshaft swings around as mentioned above, sufficient clearance is provided to prevent the labyrinth from coming into contact with the shaft and seizing the shaft, making it possible to sufficiently seal the mist under pressure. This resulted in problems such as contaminating the exterior of the engine, loss of expensive lubricating oil, and gas leaking into the engine room, making it uncomfortable to live in.

Figure 2 shows a method using an oil seal to achieve good sealing.
There is one described in No. 57-43341. Although this method prevents oil and gas from flowing out, there are problems with durability against whirling around the end of the crankshaft, lubricity of the oil seal lip, and difficulty in inserting an integral oil seal. There is a practical problem that this is the case.

In addition, as shown in Fig. 1, there is also a method of attaching a screw labyrinth in the opposite direction to the rotational direction of the shaft, as shown in Fig. 3, but as mentioned above, sufficient clearance must be provided, so the seal There are disadvantages such as insufficient rotation, and when the rotation direction is reversed as in a marine engine, it promotes the outflow of oil and gas.

The present invention aims to improve these shortcomings.It is a string-like coil made of carbon fiber that has load capacity, speed resistance, and heat resistance, and has good sealing properties. One or several packings are arranged in a cylindrical shape at the sealing part with the crankshaft, and by applying an appropriate load with a bolt and packing holder, the elastic coil packing is deformed and sealed. Embodiments of the present invention will be described below with reference to the drawings.

In FIG. 4, a gasket mounting hardware 5 is fixed at a position where the crankshaft end 3 of the crankcase 1 protrudes from the crankcase. On the other hand, the packing 6 used is a string-like coil packing made of carbon fiber, and has load capacity, speed resistance, and heat resistance. The gasket mounting hardware 5 is the gasket insertion part 7
A space is provided between the outer periphery of the crankshaft end 3 and the packing fitting 5 to form a stuffing box. The coil packing 6 extends on the outside of the packing holder 8 so that force is applied to the outer periphery of the packing by the packing holder 8 in the axial direction, and the coil packing 6 is provided between the inner periphery and the outer periphery of the crankshaft end 3. 6 is surrounded. In addition, the packing presser 8 has at least two parts as shown in FIG.
The mounting bolt 9 of the packing holder 8 is attached to a disc spring 10 so that it can be attached to the mounting hardware 5, and the coil packing has elasticity.
Use as a zakin. The one shown in FIG. 6 is another embodiment in which a plate spring 11 is attached to the outer periphery of the coil packing 6.
In this case, the outer periphery of the packing holder 8 does not extend, and the packing holder pushes the coil packing in the axial direction.
Other details are the same as in Figure 4.

Next, to explain the effects of the present invention, the coil packing 6 and the packing holder 8 are inserted into the gap between the crankshaft end 3 and the packing fitting 5, and the packing holder is fixed with a bolt 9. The coil packing 6 is in close contact with the outer periphery of the crankshaft end 3 and the mounting hardware 5, and in the axial direction, the mounting hardware 5 is elastically pressed and sealed by the action of the disc spring 10 used for the bolt 9, and in the circumferential direction. As for the disc spring 10 used for the dowel bolt 9' of the two-piece part of the seal presser and the seal presser 8.
The thin outer peripheral part of the coil packing 6 elastically presses the crankshaft surface, and in the case of FIG. 6, the leaf spring 11 on the outer periphery of the coil packing 6 elastically presses the coil packing 6. Press to seal the crankshaft surface. In general, the coil packing is elastically pressed in the axial direction by the action of the packing presser 8 and in the axial direction by the spring mechanism on the outer periphery of the coil packing to achieve sealing. Therefore, it has a sufficient buffering effect against the whirling load peculiar to the crankshaft, and even if the coil packing wears out due to friction with the shaft, it will automatically follow up with the reaction force of the coil spring, so that the sealing effect will not be impaired. This is what I did. The above description has been about the part where the shaft end of the crankshaft protrudes from the crankcase, but the present invention is applied to the shaft seal part of such an internal combustion engine that rotates while vibrating in the vertical direction. By applying the present invention to a bearing of an intermediate shaft from an engine to a marine propeller, it is possible to sufficiently adjust the runout in the axial direction and the circumferential direction.

As can be understood from the above explanation, the present invention is a sealing device for a crankshaft or bearing of an internal combustion engine, in which a string-like coil packing made of carbon fiber is placed in a stuffing box provided on the outer circumference of the shaft so as to be in contact with the circumference of the shaft. When inserted, a packing retainer split into at least two parts is fixed to the stuffing box, and a spring mechanism is interposed on the outside of the packing, so that the crankshaft deforms under the load of the cylinder's explosion pressure. Instead of the conventional labyrinth, which moves when swung around and leaks gas and oil inside the crankcase to the outside of the crankcase, we have created a labyrinth that reliably seals the shaft without contaminating the area around the engine. It can improve seizing and lubricating oil leakage all at once, and its effects are extremely large.

[Brief explanation of the drawing]

1, 2, and 3 are side sectional views for explaining a conventional sealing device, FIG. 4 is a partial side sectional view for explaining an embodiment of the present invention, and FIG. 5 is a side sectional view for explaining a conventional sealing device. A
- A view in the direction of arrows, and FIG. 6 is a partial side sectional view showing another embodiment. 1...Crankcase, 2...Oil drainer, 3...
Crankshaft shaft end, 4... Labyrinth part, 5... Packing mounting hardware, 6... Coil packing, 7...
Packing insertion part, 8... Packing holder, 9, 9'
... Bolt, 10 ... Belleville spring, 11 ... Leaf spring.

Claims (1)

[Scope of utility model registration request] In a sealing device for a crankshaft or a bearing of an internal combustion engine, a string-like coil packing made of carbon fiber is inserted into a stuffing box provided on the outer circumference of the shaft so as to be in contact with the circumference of the shaft, and at least two
A shaft sealing device for an internal combustion engine, in which a split packing retainer is fixed to the stuffing box, and a spring mechanism surrounding the coil packing from the outer periphery is interposed on the outside of the packing.