JPS61149513A - Condenser type cooling water device in horizontal engine - Google Patents

Abstract

PURPOSE:To make it possible to sustain the inside of a condenser at a high pressure to prevent the cooling performance thereof from lowering, by connecting one end of a pressure buffer pipe to an upper tank in a condenser type cooling device and by connecting the other end of the pipe to a pressurizing valve supported to an engine body. CONSTITUTION:A cylinder in which a piston is slidably disposed is integrally incorporated with one side of a crank casing 2, and the top part of a water jacket 12 formed around the cylinder is opened to the upper surface of the crank casing 2. a condenser 15 is planted on a hollow base 14 which is attached such that it closes the opening of the water jacket 12. In the condenser 15, steam from boiled cooling water is cooled and condensed by heat radiation pipes 19 with the use of cooling air from a fan 21. With this arrangement, one end of a pressure buffer pipe 22 led from the upper tank 20 is connected to a bottomed cylindrical container 23 in a pressurizing valve 25 attached to the base 14 to sustain the inside of the condenser 15 in the pressurized atmosphere.

Description

[Detailed Description of the Invention] (Industrial Application Field) This invention relates to a cooling device for a horizontal engine, and in particular, it generates steam in a water jacket, guides the steam into a heat radiation pipe of a condenser, and guides the steam through the heat radiation pipe. This relates to a condenser-type cooling device that cools and condenses steam by exchanging heat with outside air.

(Prior art) A cooling method in which water is evaporated within a water jacket and the steam is guided to a heat radiation tube to cool and condense. Since the latent heat of evaporation is used, the amount of cooling is smaller than that in which water is circulated. This has the advantage that it can be cooled with water, but it has the disadvantage that if the cooling efficiency is low, the cooling water will be lost.

Therefore, in order to prevent cooling water from dissipating, an auxiliary tank is installed on the side of the condenser, and the upper tank of the condenser and the lower part of the auxiliary tank are connected through a connecting pipe with heat dissipation fins. A pressure regulating valve is installed in the
There is a known system in which the steam flowing out from the upper tank is cooled while passing through a connecting pipe, and the condensed water generated by this cooling is stored in an auxiliary tank (Jikko Sho 4).
No. 4-28022).

(Problems to be Solved by the Invention) In the conventional example described above, heat radiation fins are provided in the connecting pipe that connects the upper tank and the auxiliary tank, and the steam is condensed and liquefied in the connecting pipe, and the steam is liquefied in the auxiliary tank. Since the engine is configured to store 88 water, if the engine is operated continuously for a long time, there may be a shortage of cooling water. Furthermore, since the steam condenses in the connecting pipe, the pressure in the 7nova tank (connecting pipe) becomes low, and the temperature at which condensation starts in the condenser pipe becomes low. As a result, the steam begins to condense at a high position in the condenser pipe, and the condensed water begins to flow down inside the condenser pipe, but the steam rising one after another comes into contact with the condensed water and the amount of condensed water increases, causing the condensed water to The condenser pipe is blocked at a high position, and the condensed water blocking the condenser pipe is pushed out by steam pressure, causing thermal changes that cause the joint between the condenser pipe and the upper tank to expand and contract, for example. 1
This process is repeated at a fast rate of three times per minute, which causes the problem that the shear resistance of the brazed material (hang, etc.) at the joint is lost due to the repeated stress, causing the joint to break.

In addition, in the conventional example described above, the condensed water in the auxiliary tank is sucked back into the water tank by opening the air inside the water jacket and dropping the pressure in the radiator due to the temperature drop due to the shutdown. However, in this case, the condensed water in the auxiliary tank cannot be completely sucked back due to the head pressure.

Therefore, in engines equipped with such a cooling system, the condensed water in the auxiliary tank freezes during cold seasons, and the pressure valve attached to the auxiliary tank (pressure camp) must be opened after the start of operation until the condensed water freezes. ) will no longer operate, causing an abnormal pressure rise inside the radiator and damaging the radiator.

(Another means to solve the problem) The present invention sets the condensation start position at a low position of the condenser pipe by maintaining the pressure in the upper tank high, and also dissipates heat even in cold seasons. To this end, in a condenser-type water cooling system for a horizontal engine, the starting end of a pressure buffer pipe is connected to the upper tank, and a pressurizing valve is connected to the ending end of the pipe. The pressurizing valve is characterized by being supported by the outer shell constituent member of the Ninnon main body.

(Function) In the present invention, in a condenser type water cooling system for a horizontal engine, the starting end of the pressure buffer pipe is connected to the upper tank, and the pressurizing valve is connected to the terminal end of the pressure buffer pipe. Changes in pressure inside the valve will be buffered by the pressure buffer pipe, and the pressurizing valve will not operate due to small and shocking pressure changes. As a result, since the condenser is under pressure, the steam starts condensing at a high temperature and condenses at the bottom of the heat dissipation tube, allowing the condensed water to quickly return to the water jacket.
Prevents heat radiation pipes from being clogged with condensed water. This prevents the joint between the heat radiation pipe and the upper tank from being damaged due to expansion and contraction due to thermal changes caused by the steam pressure pushing out the condensed water blocking the heat radiation pipe. In addition, since the steam starts condensing from the bottom of the heat dissipation pipe, most of the steam condenses by the time it reaches the upper tank, so the steam does not act on the pressure valve, and condensed water does not accumulate in the pressure valve area. do not have. This prevents condensed water from freezing in the pressurizing valve even during cold seasons.

Even if moisture in the steam were to condense and freeze on the pressurizing valve, the amount of moisture would be extremely small, and since the pressurizing valve is supported by the outer component of the engine body, the engine It is thawed by the heat generated during startup, and the pressurizing valve quickly returns to normal operation.

(Example) FIG. 1 is a vertical sectional side view of a main part, FIG. 2 is a partially vertical front view of a horizontal gas engine equipped with a condenser type cooling device, and FIG. 3 is an exploded perspective view.

This engine body (E) is equipped with a cylinder (4) in which a piston (3) is fitted in a horizontally movable manner on the lateral side of a crankcase (2) that supports a crankshaft (1), and a spark plug ( 5), a cylinder head (8) equipped with an intake/exhaust valve (6), a rocker arm (7), etc., and a crankshaft (1) as an accessory device.
The flywheel (9) and air cleaner (
10), 77 (11) and condenser type cooling device (C
) will be provided.

A water jacket (1
2) is formed, and this water jacket (12) communicates with the cooling water jacket (13) in the cylinder head (8), and the upper part of the water jacket (12) is opened on the upper surface of the crankcase (2). It is. A hollow base portion (14) is attached to close this opening, and a capacitor (15) is erected on this base (14).

The front lower part of the base (14) is attached to the water jacket [2].
), and a capacitor mounting seat (16) is formed at the rear of the wall of the base (14) to surround the opening (17). 4
The bottom plate (18) of the condenser (15) is fixed to (16) to create a structure that prevents boiling water from flowing directly into the condenser (15) from the water jacket (12).

The condenser (15) introduces the steam in the base into a group of finned heat dissipation tubes (19) and transfers it to the upper tank (20).
The cooling air from the fan (21) is used to dissipate heat and cause the condensed water to flow down along the heat dissipation pipe (19) and return to the water jacket (12).

The cooling device (C) of the present invention has the following configuration added to the basic configuration described above.

That is, as shown in FIG. 1, a pressure buffer pipe (22) is led out from the upper tank (20), and a bottomed cylindrical container (23) and its opening are installed above the base (14). a pressurizing valve (2) consisting of a closing pressure cap (24);
5) and connect the upper tank (20) to the pressurizing valve (25).
) is connected to the pressure buffer pipe (22). The pressure buffer pipe (22) is formed of a tube with a narrow inner diameter, and the inside thereof is formed into a narrow and long passage.

With this configuration, pressure fluctuations occurring in the seven-bar tank (20) are buffered by the pressure buffer pipe, so the pressure set by the pressure valve remains in the upper tank. This creates a pressurized atmosphere inside the condenser, and the temperature at which steam starts to condense increases.

As a result, the efficiency of steam condensation within the condenser is high, and no steam leaks.

By the way, when a 13.5PS, 1900cc gas engine was operated for 8 hours with 20% antifreeze, an ambient temperature of 45°C, and full water, the cooling water and vapor that overflowed outside the condenser escaped outside the condenser. As a result of measuring the amount of water, it was found that the amount of cooling water decreased by 2042 cc in the case of the condenser that was open to the atmosphere, but in the case of the present example, the amount of decreased amount of cooling water was zero.

In the figure, reference numeral (26) is a water supply port disposed on the base (14), and this water supply port (26) is closed by a pressure regulating valve (27) set at a higher pressure than the pressurizing valve (25). Further, reference numeral (28) is a pipe for setting the level of cooling water in the water shaker (12).

In addition, in the above embodiment, the pressurizing valve (25) is connected to the base (14).
), but the pressurizing valve (25) is placed on the crankcase (
2) or the cylinder head (8) or the like. Further, the pressure buffer pipe (22) may have a constricted portion in the middle thereof. Furthermore, if the pressure buffer pipe (22) is made of a non-metallic pipe with excellent insulation properties, no pressure drop will occur within the pressure buffer pipe (22), and the inside of the fundensa will be maintained at a high pressure. I can do it.

(Effects) In a condenser type water cooling system for a horizontal engine, the present invention connects the starting end of the pressure buffer pipe to the upper tank, and also connects the pressurizing valve to the terminal end of the pipe. The small pressure fluctuations that occur are absorbed by the open pressure V& I can do it. As a result, the condensation start temperature of the steam becomes higher, and the condensation starts at a lower position in the heat radiation tube, and the exchange of condensed water and steam in the bright heat radiation tube is performed smoothly, and the steam transfers the condensed water into the upper tank. It will no longer be pushed out. As a result, repeated thermal stress due to sudden temperature changes will not be applied to the joint between the 77% tank and the heat sink, thereby eliminating damage to the joint between the upper tank and the heat sink and improving durability. I can do it.

In addition, since the condensation start position in the condenser is low,
Since condensation is completed within the heat dissipation tube, there is almost no consumption of cooling water, and it is possible to prevent a decrease in cooling performance due to a drop in the cooling water level.

Furthermore, since the pressure valve is supported by the outer component of the engine body, the pressure valve is heated by heat conduction (direct and radiation) from the engine body, and even if the pressure valve freezes in cold weather, By the time steam begins to be generated within the water jacket and the pressure within the condenser increases, the pressurizing valve is thawed, and the operation of the pressurizing valve can be quickly normalized.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a longitudinal sectional side view of a main part, FIG. 2 is a partially longitudinal sectional front view of a horizontal engine, and FIG. 3 is an exploded perspective view. DESCRIPTION OF SYMBOLS 12...Water jacket, 15...Condenser, 16...Mounting seat, 17...Top opening of (12), 18...Bottom plate of (15), 19...Radiation pipe, 20
・-・7 tube tank, 22...pressure buffer pipe,
25... Pressure valve, E... Engine body, C... Cooling device, F... Outer structure member. Patent applicant Kubota Iron Works Co., Ltd. 2F (Lu

Claims (1)

[Claims] 1. A top opening (17) of the water jacket (12) and a mounting seat (16) surrounding it are formed on the top wall of the water jacket (12) of the horizontal engine; 16
), the bottom plate (18) of the condenser (15) is fixed to the bottom plate (18), and the lower ends of the many heat dissipation tubes (19) of this condenser (18) are fixed to the bottom plate (18), and the upper ends are fixed to the upper tank (2).
In the condenser-type water cooling system for a horizontal engine, which is fixed by penetrating the lower wall of the main body (0) and brazing with a brazing material, the pressurizing valve (25) is supported by the outer component (F) of the engine body (E). , a condenser type water cooling device 2 for a horizontal engine, characterized in that the pressurizing valve (25) and the upper tank (20) are connected through a pressure buffer pipe (22), and the pressure buffer pipe (22) is thin. The condenser type water cooling device 3 for a horizontal engine as set forth in claim 1 formed of a long pipe, the claim 1 of claim 1 in which the pressure buffer pipe (22) is formed of a pipe having a constriction part in the middle, or Claims 1 and 2, in which the condenser-type water cooling device 4 for a horizontal engine described in claim 2, and the pressure buffer pipe (22) are formed of a pipe made of a non-metallic material with excellent heat insulation properties.
Condenser-type water cooling system for horizontal engines described in Section 3 or Section 3