JPH07279790A - Trochoid pump - Google Patents

Abstract

PURPOSE:To improve the volumetric efficiency of a single-port type trochoid pump whose inlet and outlet openings are opened in different directions. CONSTITUTION:An internally gearing trochoid rotor 14 is provided in a housing 1, and an inlet opening 8 is provided on the slide face on one side of the housing 1, and an outlet opening is provided on a slide face on the other side. Through holes 20, 21 passing through both the sides of at least one of the outer rotor 16 and inner rotor 15 of the trochoid rotor 14 are provided in the toothed part of the above rotor. The slide face on the other side of the housing 1 is provided with a guide groove 23 through which fluid flowing from the inlet opening 8 into the through holes 20, 21 can be sucked into between the rotors 15, 16 from a face on a side of anti-inlet opening.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a trochoid pump (also referred to as an internal gear pump) which is used as an in-tank type fuel pump for automobiles and which performs a pumping action by the rotation of an internally meshed trochoid rotor.

[0002]

2. Description of the Related Art Conventional trochoid pumps include, for example, a so-called in-tank fuel pump which is integrally provided with a motor portion and is arranged in a fuel tank of an automobile. An example of this type of trochoid pump will be described with reference to FIGS. 4 and 5. 4 is an exploded perspective view, FIG. 5 (a) is a schematic plan view, and FIG. 5 (b) is a schematic sectional view. The cylindrical housing 1 of the trochoid pump includes a ring-shaped case 2, a discharge side plate 3 and a suction side plate 4 provided on both sides (upper and lower sides in the drawing) of the case 2, and a lower side of the suction side plate 4. It is fastened to the provided body 5 by a screw 6, and a cylindrical pump chamber 7 is formed therein. The suction side plate 4 and the body 5 are provided with continuous suction ports 8, and the discharge side plate 3 is provided with a discharge port 10. On the body 5, the support shaft 1 protruding into the pump chamber 7 is provided.
1 is provided. Hollow holes 12 and 13 are formed in the respective axial center portions of the discharge side plate 3 and the suction side plate 4.

The pump chamber 7 houses a trochoid rotor 14 which is inscribed and meshed. The trochoid rotor 14 includes an inner rotor 15 having outer teeth and an outer rotor 16 having inner teeth meshing with the outer teeth. The inner rotor 15 is rotatably supported by the support shaft 11 of the body 5. The inner rotor 15 has a housing 1
The shaft of an armature of a motor (not shown) integrally provided on the upper side is connected through a joint. In addition, the inner rotor 15 is provided with a joint hole 17 for joint connection.

In the trochoid pump, the trochoid rotor 14 is operated as the motor is driven by turning on an ignition switch using a battery (not shown) of an automobile or the like as a power source. As a result, the fuel in the fuel tank is sucked between the rotor 5 and the rotor 16 of the trochoid rotor 14 from the suction port 8 of the body 5 and the suction side plate 4, and is discharged into the motor (not shown) from the discharge port 10 of the discharge side plate 3. It is discharged, passes through the inside of the motor upward, and then is sent to the engine outside the motor, that is, through the fuel supply pipe.

[0005]

Since the trochoid pump is a so-called single-port type pump in which fuel is sucked from one suction port 8 on one side, volumetric efficiency is poor. However, since the intake port 8 and the discharge port 10 are opened in different directions, that is, on each side surface of the trochoid rotor 14, the flow path connecting to the intake port 8 and the discharge port 10 is easy to handle, and is suitable as a fuel pump for automobiles. Can be said to be. Further, as a single port type pump, there is JP-A-61-155685. With this pump,
The suction port and the discharge port are in the same direction, that is, the trochoid rotor 1
Since it is opened on one side surface of No. 4, it is difficult to handle the flow path connected to the intake port and the discharge port when it is used as an automobile fuel pump, and it is difficult to apply it as an automobile fuel pump.

In order to improve the volumetric efficiency, the suction port is
It is known to make it a double port type that has several locations. For example, in the single-port type trochoid pump, as shown in FIGS. 6 and 7, a suction port 18 that is opposed to the suction port 8 of the suction side plate 4 is added to the discharge side plate 3. 6 is an exploded perspective view, FIG.
(A) is a schematic plan view and (b) is a schematic sectional view. In this way, fuel can be sucked from the suction ports 8 and 18 on both sides of the trochoid rotor 14, and the volumetric efficiency is improved. However, when the suction ports 8 and 18 are provided on both sides of the trochoid rotor 14, the discharge port 10 and the suction port 18 of the discharge side plate 3 open in the same direction, that is, on one side surface of the trochoid rotor 14. 61-1
As in Japanese Patent No. 55685, there is a concern that the handling of the flow path connecting the discharge port 10 and the suction port 18 may be complicated, and the length of the pump may be increased and the size may be increased due to the complicated handling. However, its application as a fuel pump for automobiles is difficult.

Therefore, the present invention has been made to solve the above-mentioned problems, and an object thereof is to improve the volumetric efficiency of a single port type in which a suction port and a discharge port are opened in different directions. The object is to provide a trochoid pump that can be used.

[0008]

In order to achieve the above-mentioned object, the present invention provides a trochoid rotor which is intermeshed with each other in a housing, and has an inlet on one sliding surface side of the housing and the other. In the trochoid pump having a discharge port on the sliding surface side thereof, a through hole penetrating both side surfaces of the rotor is provided in a tooth portion of at least one of the outer rotor and the inner rotor of the trochoid rotor, and the other of the housings is provided. A trochoid pump is provided on the sliding surface side, with a guide groove being provided between the rotors so that the fluid flowing into the through hole from the suction port due to the operation of the trochoid rotor can be sucked from the surface on the side opposite to the suction port.

[0009]

According to the present invention, when the trochoid rotor is operated, the fluid is sucked from the suction port of the housing between the rotors of the trochoid rotor, and the through hole facing the suction port is provided between the rotors through the guide groove. The fluid is also sucked from the surface on the side opposite to the suction port. The suctioned fluid is pressurized by the operation of the trochoid rotor and then discharged from the discharge port of the housing opened in a direction different from the suction port.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to the drawings. The trochoid pump of the present embodiment is shown in an exploded perspective view in FIG. 2, in a plan view in FIG. 3A, and in FIG. 3B, a sectional view taken along line AA of FIG. A sectional view taken along line BB of (a) is shown in (c). In this embodiment, a part of the conventional single-port type trochoid pump (see FIG. 4 and FIG. 5) is modified, and therefore the modified part will be described in detail and redundant description will be omitted.
Through holes 20 and 21 penetrating both side surfaces of the inner rotor 15 and the outer rotor 16 of the trochoid rotor 14 are formed in the respective tooth portions. A guide groove 23 having the same shape as the suction port 8 of the suction side plate 4 and having a face-to-face shape is formed on the rotor sliding surface of the discharge side plate 3 of the housing 1.

However, the through holes 20 and 21 are formed in the following relationship with the guide groove 23 as shown in the explanatory view of the main part of FIG. 1 (a) is a plan view of the trochoidal rotor, FIG. 1 (b) is a partial sectional view corresponding to the DD line cross section of (a), and FIG. 1 (c) is a CC line cross section of (a). Part (a) is a partial sectional view corresponding to the section taken along line BB of (a), and (e) is a partial sectional view corresponding to the section taken along line AA of (a). The through holes 20 and 21 are formed in the teeth of the rotors 15 and 16 facing the discharge port 8 and the guide groove 21 as the trochoid rotor 14 operates.
It is formed with a predetermined thickness from each tooth surface.

According to the trochoid pump, the operation of the trochoid rotor 14 sucks fluid (fuel in the case of a fuel pump) between the rotors 15 and 16 of the trochoid rotor 14 from the suction port 8 of the housing 1. From the through holes 20 and 21 facing the suction port 8, the fluid is also sucked between the rotors 15 and 16 through the guide groove 23 from the surface on the side opposite to the suction port. The trochoid rotor 1
The flow of fluid accompanying the operation of FIG.
Is indicated by an arrow. The fluid sucked between the rotors 15 and 16 is pressurized by the operation of the trochoid rotor 14, and then discharged from the discharge port 10 of the housing 1 opened in a direction different from the suction port 8.

According to the trochoid pump, the trochoid rotor 14 has suction holes 8 on both sides and the through holes 20, 2
The fluid can be sucked from both the paths from the guide groove 23 via 1 and the volume efficiency is almost the same as that of the double port type though it is the single port type. More specifically, in the intake start process of FIG. 1B, the intake volume between the rotors 15 and 16 is not so large, but the intake process proceeds with the operation of the rotor, and the intake processes (c), (d), When the suction volume gradually increases in the order of (e), a negative suction pressure is generated. Fuel is inhaled by this negative pressure, but the surface area of inhalation at this time is small on one side in the case of a normal single port type. However, in this example, the through holes 20, 21 of the rotors 15, 16 are
Since it becomes possible to inhale from the side opposite to the inhalation port 8 through, the surface area of inhalation increases, and thus inhalation efficiency increases.
Note that either one of the through holes 20 and 21 of the rotors 15 and 16 can be eliminated.

Further, unlike the double port type in which the suction ports are provided on both sides of the trochoid rotor 14, since the suction port 8 and the discharge port 10 are single port types that open in different directions, they are connected to the suction port 8 and the discharge port 10. The passage is easy to handle, and it is possible to avoid an increase in size due to the complexity of the handling. Therefore, it is suitable for a fuel pump for automobiles.

[0015]

According to the present invention, the suction port and the discharge port are different from each other by sucking the fluid from the surface on the side opposite to the suction port between the rotors through the guide groove through the through hole facing the suction port. Although it is a single port type that opens in the direction, volume efficiency can be improved.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a main part of an embodiment.

FIG. 2 is an exploded perspective view of a trochoid pump.

FIG. 3 is an explanatory view of the same abbreviation.

FIG. 4 is an exploded perspective view showing a single-port type trochoid pump.

FIG. 5 is an explanatory view of the same abbreviation.

FIG. 6 is an exploded perspective view showing a double port type trochoid pump.

FIG. 7 is an explanatory view of the same abbreviation.

[Explanation of symbols]

 1 Housing 8 Suction Port 10 Discharge Port 14 Trochoidal Rotor 20, 21 Guide Groove 23 Through Hole

Claims (1)

[Claims] 1. A trochoid pump having an intermeshing trochoid rotor provided in a housing, having a suction port on one sliding surface side of the housing and a discharge port on the other sliding surface side. At least one rotor of the outer rotor and the inner rotor of the rotor is provided with a through hole penetrating both side surfaces of the rotor, and the other sliding surface side of the housing is provided with the suction port according to the operation of the trochoid rotor. A trochoid pump provided with a guide groove that allows the fluid that has flowed into the through hole to be sucked between the rotors from the surface on the side opposite to the suction port.