JPH0330639Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an ejector that is a fluid injection pump, and in particular, it is designed to be easily manufactured using a pipe body and to reduce fluid resistance as much as possible. Regarding the ejector.

[Prior art] Internal combustion engines generally have forced exhaust inside the cylinder, etc.
An ejector is used as a means for obtaining negative pressure (Japanese Patent Application Laid-Open Nos. 57-135224, 1982-124035, etc.). That is, these ejectors are configured to generate negative pressure using a working fluid such as compressed gas, and to use this negative pressure to transfer the fluid to be transferred such as exhaust gas.

[Problems to be solved by the invention] However, since each of these conventional ejectors is assembled from several different parts, each of these parts has to be manufactured individually using completely different processes. This made production difficult and led to an increase in costs.

Therefore, in order to easily manufacture the ejector using easily available parts, an ejector has been proposed in which all the parts are molded from tube materials, as shown in FIG. In this ejector, a nozzle pipe b whose inner diameter is gradually reduced in the flow direction is inserted into a pipe body a for transferring working fluid, and a fluid suction pipe is provided on the side wall of the pipe body a facing the side surface of the small diameter part of the nozzle pipe b. It has a structure in which c is connected.

However, in the case of the above ejector, the tube body a
Since it is necessary to insert the nozzle pipe b into the nozzle, position it, braze it, etc., there is a problem that the work is difficult and time-consuming. Furthermore, since the base end d of the nozzle pipe b is provided facing the flow, flow path resistance increases and a sufficient ejector effect cannot be expected.

[Purpose of the invention] The present invention was devised to effectively solve the problems of the prior art described above, and its purpose is to facilitate positioning, brazing, etc., to be easily manufactured, and to reduce costs. It is an object of the present invention to provide an ejector that can reduce flow path resistance as much as possible and fully exhibit the ejector effect.

[Structure and operation of the device] The ejector of the present invention reduces the diameter of the outlet portion of the fluid discharge pipe to form a nozzle portion, and connects the inlet portion of the fluid conveying tube having the same diameter as the fluid discharge tube to the outer periphery of the fluid discharge tube. The inner diameter of the pipe is enlarged in a longer range than the nozzle part to fit and connect to the fluid discharge pipe, and a pipe is formed between the inner periphery of the enlarged diameter part of the fluid delivery pipe and the outer periphery of the nozzle part. It is formed by connecting a fluid suction pipe that communicates with an annular negative pressure chamber.

Since the fluid discharge pipe and the fluid guide pipe have the same diameter, they can be manufactured using pipe bodies with the same diameter.
Moreover, simple molding of diameter reduction and diameter expansion is sufficient.
Furthermore, since the connecting portions can be easily brazed or welded from the outside, manufacturing is easy and costs can be reduced. Further, unlike the case where the nozzle part is separate, positioning of the nozzle part is easy, flow resistance can be reduced, and the ejector effect can be fully exerted.

[Example] An example of the present invention will be described below in detail based on the accompanying drawings.

The first diagram showing the vertical cross-sectional structure of the ejector according to the present invention.
In the figure, 1 is a fluid discharge pipe that discharges working fluid such as gas (compressed air, exhaust gas, etc.), liquid (fuel, etc.), and the outlet section 2 has a nozzle section whose diameter is gradually reduced in the fluid flow direction. 3 is integrally formed by drawing molding or the like.

A fluid delivery pipe 4 for guiding the working fluid to a destination is connected to the fluid discharge pipe 1, and this delivery pipe 4 is formed to have the same diameter as the discharge pipe 1. The inlet portion 5 of the fluid delivery tube 4 has an inner diameter that is expanded to fit around the outer periphery of the fluid discharge tube 1 over a longer range than the nozzle portion 3, and is fitted and connected to the fluid discharge tube. An annular negative pressure chamber 7 is formed between the inner periphery and the outer periphery of the nozzle portion 3 and is made negative pressure by the force of fluid ejected from the nozzle portion 3 and flowing into the fluid conveying pipe 4 . The inner diameter of the enlarged diameter portion 6 is formed to a size that allows it to fit onto the fluid discharge pipe 1. The connection portion of the inlet portion 5 of the fluid conveyance pipe 4 is tightly attached to the fluid discharge pipe 1 by brazing, welding, or the like.

A fluid suction pipe 8 is connected to the enlarged diameter portion 6 by brazing or the like so as to communicate with the negative pressure chamber 7, and is configured to suck the fluid to be transferred and introduce it into the negative pressure chamber 7.

When the working fluid flows from the fluid discharge pipe 1 through its nozzle part 3 to the fluid conveying pipe 4, the negative pressure chamber 7 in the enlarged diameter part 6 becomes negative pressure, and the fluid is transferred through the fluid suction pipe 8. The fluid is sucked into the negative pressure chamber 7 and transferred together with the working fluid.

The ejector with the above configuration is installed, for example, in the fuel overflow line of a single-bank bulk car, and when the operation is switched from the main injection pump operation to only the main injection pump operation, the ejector overflows from the main injection pump and into the tank. It is used to suck in the fuel (fluid to be transferred) that overflows from the auxiliary injection pump and returns it to the tank by using the flow force of the fuel (working fluid) returning to the tank.

[Effects of the invention] In summary, the present invention provides the following excellent effects.

(1) Since the fluid discharge pipe and the fluid conveyance pipe have the same diameter, they can be manufactured using pipe bodies of the same diameter, and simple molding of diameter reduction and diameter expansion is sufficient, and the connection part Since brazing or welding can be easily done from the outside, manufacturing is easy and costs can be reduced.

(2) Furthermore, unlike those in which the nozzle part is separate, positioning of the nozzle part is easy, flow path resistance can be reduced, and the ejector effect can be fully exerted.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing an embodiment of an ejector according to the present invention, and FIG. 2 is a longitudinal sectional view showing a conventional ejector structure. In the figure, 1 is a fluid discharge pipe, 2 is an outlet thereof, 3 is a nozzle part, 4 is a fluid outlet pipe, 6 is an enlarged diameter part, and 8 is a fluid suction pipe.

Claims (1)

[Scope of utility model registration request] The diameter of the outlet part of the fluid discharge pipe is reduced to form a nozzle part, and the inlet part of the fluid conveyance pipe, which has the same diameter as the fluid discharge pipe, is fitted to the outer circumference of the fluid discharge pipe to form a nozzle part. A fluid suction pipe is provided with an enlarged diameter to fit and connect to the fluid discharge pipe, and to communicate with an annular negative pressure chamber formed between the inner circumference of the enlarged diameter part of the fluid conveyance pipe and the outer circumference of the nozzle part. Ejector that is connected.