JPH0528400Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to a water pump for internal combustion engines.
The present invention relates to a water pump structure that efficiently cools a water seal when the water seal is installed on the pressure side of the pump.

(Prior technology) Conventionally, the seals of water pumps for internal combustion engines were often installed on the suction side of the pump, so there was no need to think about seal cooling, but as engines become smaller and faster, water seals wear out. As a result, many products are installing a water seal on the pressure side to improve sealing performance. When installing a water seal on the pressure side, if water stagnates in the seal chamber, the water seal will become hot, so the structure shown in Figure 2 a and b is widely used to cool the water seal. ing.

In the figure, a is a pump body, and the pump body a houses a scroll A', a seal chamber C', and an impeller b such that they can rotate. C is a water seal, and the water seal c is press-fitted into the pump body a and a cemented carbide seal f made of superhard steel or ceramic, which is press-fitted into the impeller b, as shown in FIG. 2b. It is composed of a seal body g, a carbon seal h, and a spring i, and the carbon seal h is pressed against the carbide seal f by the spring i and water pressure and rotates to prevent water from leaking toward the bearing. are doing.

F' is a communication hole, and the communication hole F' is a drilled hole that communicates the seal chamber C' and the suction hole B', and is bored in the pump cover d and the pump body a, and the connection hole F' is a drilled hole that communicates the seal chamber C' and the suction hole B'. An O-ring e is fitted into the surface to prevent water leakage.

In this way, the high-temperature water in the seal chamber C′ is sucked into the suction hole.
The water seal c is cooled by suction into B'.

(Problem to be solved by the invention) As mentioned above, the communication hole that is drilled so that the high-temperature water in the seal chamber is sucked into the suction hole is in an inverted U shape, so vapor lock occurs and water flows out. As a result, the water seal becomes too hot, causing problems such as water leaking outside the water pump.

In addition, it takes a lot of man-hours to process the communication hole, and the small O that fits between the pump body and the pump cover.
The cost is high due to errors such as forgetting to insert the ring.

The purpose of this invention is to solve the above problems.

(Means and effects for solving the problem) This invention was made in view of the above points, and a bypass chamber is provided on the back of the scroll of the pump body to receive the bypass water of the thermostat. The bypass chamber and seal chamber are drilled in a straight line so that they communicate with the suction hole of the pump cover, and this prevents water vapor from accumulating in the passage. , the high-temperature water in the sealing chamber is sucked into the suction hole without stagnation. Therefore, the water seal is sufficiently cooled and its durability is improved, and since the connecting height can be cut in a straight line, the number of man-hours required is small and the cost can be significantly reduced.

(Example) The structural outline of an example of this invention is shown in Figure 1 a, b,
Shown in c and d. Referring to these figures, reference numeral 1 denotes a pump body, which has a scroll A, a seal chamber C, and a bypass chamber D, and rotatably houses an impeller 2 therein.

3 is a water seal, and the water seal 3 is press-fitted into the pump body 1 with a cemented carbide seal 5 made of superhard steel or ceramic, which is press-fitted into the impeller 2, as shown in FIG. 1d. It is composed of a seal body 7, a carbon seal 6, and a spring 8, and the carbon seal 6 rotates while being pressed against the carbide seal 5 by the spring 8 and water pressure, and water leaks toward the bearing 9. It prevents Although the carbide seal 5 rotates together with the impeller 2, the carbon seal 6 is stationary and generates frictional heat, so the water seal 3 is cooled by the water around it.

The water in the seal chamber C receives heat from the water seal 3 and becomes high temperature. As shown in FIGS. 1a and 1c, a bypass chamber D for receiving bypass water from the thermostat is provided on the back of the scroll, and an outlet hole E of the bypass chamber D is opened toward the suction hole B of the pump cover 4. Since the seal chamber C and the bypass chamber D are communicated with each other through a communication hole F that is drilled in a straight line to prevent vapor locking, the high temperature water that has received heat from the water seal 3 does not stagnate and flows through the suction hole B of the pump cover 4. The water around the water seal 3 always turns into new low-temperature water and cools the water seal 3.

(Effects of the invention) Since this invention is implemented as described above, water vapor does not stagnate in the communication hole between the seal chamber and the bypass chamber, and the water around the water seal is constantly replaced with low-temperature water, making it more efficient. Water seals are often cooled to increase their durability. In addition, the communication hole can be formed more easily than in the past, and a small O-ring is not required, making it possible to significantly reduce the manufacturing cost of the water pump.

[Brief explanation of drawings]

Figures 1a to d are structural diagrams of a water pump according to an embodiment of this invention, where Figure 1a is a front view seen from the drive gear side, and Figure 1b is a cross section taken along line H-H in the front view. , Figure 1c shows the state of the communication hole that communicates the seal chamber and bypass chamber of the pump body in the GG cross section,
Figure 1d shows a detailed view of the water seal;
Figure a shows a structural diagram of a conventional water pump, and Figure 2b shows a detailed diagram of a water seal. 1... Pump body, 2... Impeller, 3... Water seal, 4... Pump cover, 5... Carbide seal, 6... Carbon seal, 7... Seal body, 8... Spring, 9... Bearing, A...
...Scroll, B...Suction hole, C...Seal chamber,
D...Bypass chamber, E...Exit hole of bypass chamber,
F...Kill hole.

Claims (1)

[Scope of utility model registration request] In water pumps for internal combustion engines that have a water seal installed on the pressure side of the water pump,
A bypass chamber is provided on the back of the scroll of the pump body to receive bypass water from the thermostat that communicates with the pump suction hole, and the bypass chamber and the seal chamber on the back of the impeller are communicated through a drilled hole.
Seal cooling device for water pumps for internal combustion engines.