CN216554178U

CN216554178U - Oil stopping oil way of common rail pump

Info

Publication number: CN216554178U
Application number: CN202123160948.8U
Authority: CN
Inventors: 尤丽华
Original assignee: Wuxi Piruixin Measurement And Control Technology Co ltd
Current assignee: Wuxi Piruixin Measurement And Control Technology Co ltd
Priority date: 2021-12-15
Filing date: 2021-12-15
Publication date: 2022-05-17
Anticipated expiration: 2031-12-15

Abstract

The utility model discloses an oil stopping oil circuit of a common rail pump, which comprises a pump body (1) and a plunger sleeve (2). The outer diameter of the plunger sleeve is provided with a filtering ring (2.2) which forms a filtering gap (3) with the pump body, the pump body is provided with a throttling hole (1.1), an inlet (2.1) of the plunger sleeve is communicated to the oil tank (4) through the filtering gap (3) and the throttling hole (1.1), and the filtering gap (3) prevents particles with the diameter larger than the gap in the fuel oil from entering the throttling hole (1.1) to prevent blockage. Compared with the zero flow valve of the background art which is pressed into the pump body: zero flow valve and pressure equipment process can be saved to this structure, reduce cost, and the filtration gap (3) of this structure can be than the filtration gap of zero flow valve of the pressure income formula for a great many times little and the filter effect is better.

Description

Oil stopping oil way of common rail pump

Technical Field

The utility model relates to the technical field of common rail systems of diesel engines, in particular to an oil stopping oil way of a common rail pump.

Background

The common rail system controls rail pressure by changing high-pressure flow through a common rail pump, the common rail pump shown in the attached figure 1 changes the high-pressure flow by changing the flow entering an inlet 2.1 of a plunger sleeve 2 through an oil inlet metering valve 5, when an engine is decelerated suddenly or shifts from running to parking, the common rail pump is required to stop outputting the high-pressure flow completely, but the oil inlet metering valve 5 of a slide valve structure is sealed by a gap, even if the engine is closed, a small flow passes through the sealing gap of the oil inlet metering valve 5 under the pressure provided by an oil transfer pump 6 and flows to the inlet 2.1 of the plunger sleeve, the leaked small flow is required to be led back to the oil tank 4 through a throttling hole 3.1 of a zero flow valve 3, and the high-pressure flow generated by entering the inlet 2.1 of the plunger sleeve is avoided. The flow rate that orifice 3.1 can pass must be slightly greater than the leakage flow rate of oil feed metering valve 5, and the small can not guarantee the oil pump stops oil completely, and big reduces the startability of engine. A radial gap between a filter ring 3.2 on the outer diameter of the zero flow valve 3 and the pump body 1 forms a filter gap 3.3, fuel can only reach the throttling hole 3.1 after passing through the filter gap 3.3, and particulate matters with the diameter larger than the filter gap in the fuel are intercepted by the gap, so that the throttling hole 3.1 is prevented from being blocked. With the oil inlet metering valve 5 opened gradually, the flow rate flowing through the oil inlet metering valve 5 exceeds the micro flow rate which can pass through the throttling hole 3.1, and the surplus part enters the plunger sleeve inlet 2.1 to generate high-pressure flow rate.

The disadvantage of this structure is that the outer diameter of the zero flow valve 3 is limited by space, the perimeter of the filter gap 3.3 is small, and in order to avoid that the filter gap 3.3 generates extra throttling to influence the micro flow value determined by the orifice 3.1, a wider filter gap is needed, which reduces the capability of filtering particles.

SUMMERY OF THE UTILITY MODEL

Utility model purpose: in order to overcome the defects in the prior art, the utility model provides the oil stopping oil circuit of the common rail pump, which can omit the zero flow valve 3 in the attached drawing 1 and greatly increase the perimeter of the filtering gap, thereby reducing the width of the filtering gap and trapping smaller particles.

The technical scheme is as follows: in order to achieve the purpose, the oil stopping oil circuit of the common rail pump comprises a throttle hole on a pump body and a filtering gap between a filtering ring on a plunger sleeve and the pump body. The throttling hole is located on the pump body, a filtering ring is arranged on the outer diameter of the plunger sleeve, a filtering gap is formed by a radial gap between the filtering ring and the pump body, and the throttling hole is aligned to the upper portion of the filtering gap.

Has the advantages that: compared with the prior art, the oil stopping oil circuit of the common rail pump saves a zero flow valve and a press fitting process, reduces the cost, can filter smaller particles and eliminates the risk of blockage of a throttle hole.

Drawings

FIG. 1 is an oil cut-off circuit composed of a press-fitting type zero flow valve adopted in the background art;

FIG. 2 is a block diagram of the present invention.

Detailed Description

The present invention will be further described with reference to the accompanying drawings.

As shown in the attached figure 2: an oil stopping oil circuit of a common rail pump is characterized in that a throttle hole 1.1 is formed in a pump body 1, a filter ring 2.2 is arranged on a plunger sleeve 2, and a filter gap 3 is formed by a gap between the pump body 1 and the filter ring 2.2. The throttle hole 1.1 is aligned above the filtering gap 3, when the engine is decelerated suddenly or shifts from running to parking, the common rail pump is required to stop outputting high-pressure flow completely, the oil inlet metering valve 5 is closed, and under the pressure provided by the oil transfer pump 6, the leakage flow which passes through the sealing gap of the oil inlet metering valve 5 and flows to the plunger sleeve inlet 2.1 flows back to the oil tank 4 through the filtering gap 3 and the throttle hole 1.1, so that the high-pressure flow generated by entering the plunger sleeve inlet 2.1 is avoided. The filter slits 3 trap particles possibly contained in the fuel, avoiding clogging the orifice 1.1.

The circumference of the filter slot 3 in fig. 2 is many times larger than the circumference of the filter slot 3.3 in fig. 1, and the width of the filter slot 3 in fig. 2 can be reduced many times with the same flow cross-section, so that particles of a diameter much smaller than the diameter of the throttle orifice 1.1 are retained, completely eliminating the risk of clogging of the throttle orifice 1.1. With the oil inlet metering valve 5 opened gradually, the flow rate flowing through the oil inlet metering valve 5 exceeds the micro flow rate which can pass through the throttling hole 1.1, and the surplus part enters the plunger sleeve inlet 2.1 to generate high-pressure flow rate.

The above description is only of the preferred embodiments of the present invention, and it should be noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the utility model and these are intended to be within the scope of the utility model.

Claims

1. An oil stopping oil circuit of a common rail pump comprises a throttle orifice (1.1) on a pump body (1), a filter ring (2.2) on a plunger sleeve (2) and a filter gap (3) between the pump body (1); the method is characterized in that: the throttling hole (1.1) is located on the pump body (1), a filtering ring (2.2) is arranged on the outer diameter of the plunger sleeve (2), a filtering gap (3) is formed by a radial gap between the filtering ring (2.2) and the pump body (1), and the throttling hole (1.1) is aligned to the upper portion of the filtering gap (3).