JP2023090295A - high pressure fuel supply pump - Google Patents

Abstract

To provide a high pressure fuel supply pump capable of improving bonding force of a body, a damper cover and a lower support member.SOLUTION: A high pressure fuel supply pump 100 includes: a damper 9 for reducing pressure pulsation; a lower support member 22 supporting the damper 9; a damper cover 20 covering the damper 9 and the lower support member 22; a body 1; and a welding mark (welding part W) formed by a laser on a contact surface (abutment surface BU) between the damper cover 20 and the body 1. The welding mark has a penetration shape 41 branched into two portions with respect to the thickness direction of the lower support member 22.SELECTED DRAWING: Figure 5C

Description

The present invention relates to high pressure fuel supply pumps.

As a background art of the present invention, a high-pressure pump described in WO2020/195222 (Patent Document 1) is known.

The fuel pump of Patent Document 1 includes a body, a damper cover (cover portion) that covers the body, a lower support member (support member) that supports the damper (accommodated portion), and between the lower support member and the damper cover. A press-fitting portion (first press-fitting portion) is formed to fix the lower support member to the damper cover, and a surface that is the same as the surface on which the press-fitting portion of the lower support member is formed and is formed between the lower support member and the body (the and a press-fitting portion (second press-fitting portion) formed in the outer peripheral surface portion) for fixing the lower support member to the body (paragraph 0047).

In addition, the damper cover (cover portion) and the body are arranged so as to be in contact with each other to form an abutting portion (contact surface) (paragraph 0049). are welded by irradiating a laser on (paragraph 0050). Furthermore, the melted portion of the welded portion reaches the side portion of the lower support member, and is so deep that a part of the side portion in the thickness direction (peripheral side) is melted (Paragraph 0051).

WO2020/195222

In Patent Document 1, it is described that only a part of the side surface of the cylindrical member (lower support member) is welded at the welded portion, and there is a possibility that sufficient bonding force cannot be secured against the recent increase in fuel pressure. There is

SUMMARY OF THE INVENTION It is an object of the present invention to provide a high-pressure fuel supply pump capable of improving the coupling force between a body, a damper cover and a lower support member.

In order to achieve the above object, the high-pressure fuel supply pump of the present invention includes a damper that reduces pressure pulsation, a lower support member that supports the damper, a damper cover that covers the damper and the lower support member, and a body. and laser welding marks formed on contact surfaces between the damper cover and the body. The weld mark has a penetration shape bifurcated in the thickness direction of the lower support member.

According to the present invention, it is possible to improve the coupling force between the body, the damper cover and the lower support member. Problems, configurations, and effects other than those described above will be clarified by the following description of the embodiments.

1 is a conceptual diagram showing the configuration of an engine system to which a high-pressure fuel supply pump according to one embodiment of the present invention is applied; FIG. FIG. 4 is a cross-sectional view showing a cross-section parallel to the axial direction of the plunger of the high-pressure fuel supply pump according to one embodiment of the present invention; FIG. 3 is a cross-sectional view showing a cross-section perpendicular to the axial direction of the plunger seen from above the high-pressure fuel supply pump of FIG. 2 ; FIG. 3 is a sectional view showing a section around the damper cover of FIG. 2; It is sectional drawing of the abutment part before welding. It is a sectional view showing penetration shape after welding of the 1st round. It is a sectional view showing penetration shape after welding of the 2nd round.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

First, a high-pressure fuel supply pump 100 according to one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a conceptual diagram showing the configuration of an engine system to which a high-pressure fuel supply pump according to one embodiment of the invention is applied. In the following description, the vertical direction may be specified, but this vertical direction is based on the vertical direction in FIG. 1 and does not necessarily match the vertical direction when the high-pressure fuel supply pump 100 is mounted.

A portion surrounded by a dashed line indicates the main body of a high-pressure fuel supply pump (hereinafter referred to as a fuel pump) 100, and the mechanisms and parts indicated within the dashed line are integrated with a body 1 (which may be referred to as a pump body). built in.

Fuel in a fuel tank 103 is pumped up from the fuel tank 103 by a feed pump 102 based on a signal from an engine control unit 101 (hereinafter referred to as ECU). This fuel is pressurized to a suitable feed pressure and sent through a fuel line 104 to the low pressure fuel inlet 10a of the fuel pump. The low-pressure fuel intake port 10a is provided in the intake pipe 5 (see FIG. 2).

The fuel flowing from the low-pressure fuel intake port 10a reaches the intake port 3k of the electromagnetic intake valve mechanism 3, which is a variable displacement mechanism, through a damper (damper mechanism) 9, which is a pressure pulsation reduction mechanism, and an intake passage 10d.

The fuel that has flowed into the electromagnetic intake valve mechanism 3 passes through the intake valve 3b, flows through the intake passage 1z formed in the body 1, and then flows into the pressurization chamber 11. As shown in FIG. A cam 91 (see FIG. 2) of the engine powers the plunger 2 to reciprocate. Due to the reciprocating motion of the plunger 2, fuel is sucked from the intake valve 3b during the downward stroke of the plunger 2, and the fuel is pressurized during the upward stroke.

When the pressure in the pressurizing chamber 11 exceeds a set value, the discharge valve mechanism 8 opens, and the common rail 106 with the pressure sensor 105 is fed through the fuel discharge port 12a provided in the discharge joint 12 (see FIG. 2). High pressure fuel is pumped to Based on a signal from the ECU 101, the injector 107 injects fuel into the engine. The fuel pump 100 of this embodiment is a fuel pump applied to a so-called direct injection engine system in which an injector 107 directly injects fuel into a cylinder of an engine. The fuel pump 100 discharges a desired flow rate of fuel in response to a signal from the ECU 101 to the electromagnetic intake valve mechanism 3 .

FIG. 2 is a cross-sectional view showing a cross-section parallel to the axial direction of the plunger 2 of the high-pressure fuel supply pump according to one embodiment of the present invention. FIG. 3 is a cross-sectional view showing a cross-section perpendicular to the axial direction of the plunger 2 as seen from above the high-pressure fuel supply pump of FIG.

The fuel pump 100 is fixed to a fuel pump mounting portion of the engine (internal combustion engine) with a plurality of bolts using a mounting flange 1e (see FIG. 3) provided on the body 1. As shown in FIG.

As shown in FIG. 2, the body 1 is attached with a cylinder 6 that guides the reciprocating motion of the plunger 2 and forms a pressure chamber 11 together with the body 1 . The body 1 is also provided with an electromagnetic intake valve mechanism 3 for supplying fuel to the pressurizing chamber 11 and a discharge valve mechanism 8 (see FIG. 3) for discharging fuel from the pressurizing chamber 11 to the discharge passage. ing.

The cylinder 6 is press-fitted into the body 1 on its outer peripheral side. The pressurization chamber 11 is composed of a body 1 , an electromagnetic suction valve mechanism 3 , a plunger 2 , a cylinder 6 and a discharge valve mechanism 8 .

A tappet 92 is provided at the lower end of the plunger 2 to convert the rotary motion of a cam 91 attached to the camshaft of the engine into vertical motion and transmit the vertical motion to the plunger 2 . The plunger 2 is pressed against the tappet 92 by the spring 18 via the retainer 15 . As a result, the plunger 2 can be reciprocated up and down as the cam 91 rotates.

A plunger seal 13 held at the lower end portion of the inner periphery of the seal holder 7 is installed in a state of slidably contacting the outer periphery of the plunger 2 at the lower portion of the cylinder 6 in the drawing. As a result, when the plunger 2 slides, the fuel in the auxiliary chamber 7a is sealed and prevented from flowing into the engine. At the same time, it prevents lubricating oil (including engine oil) for lubricating sliding parts in the engine from flowing into the interior of the body 1 .

The relief valve mechanism 4 shown in FIGS. 2 and 3 is composed of a seat member 4e, a relief valve 4d, a relief valve holder 4c, a relief spring 4b, and a spring support member 4a. The relief valve 4d cuts off the fuel when the biasing force of the relief spring 4b acts via the relief valve holder 4c and is pressed against the seat member 4e. The relief valve mechanism 4 is configured to open the relief valve 4d against the biasing force of the relief spring 4b when the differential pressure between the upstream side and the downstream side of the relief valve 4d exceeds a set pressure. .

In this embodiment, the relief valve mechanism 4 communicates with the pressure chamber 11 via the relief passage, but is not limited to this, and communicates with the low pressure passage (low pressure fuel chamber 10, intake passage 10d, etc.). You can make it work. The relief valve mechanism 4 is a valve configured to operate when some problem occurs in the common rail 106 or a member therebehind and the common rail 106 becomes abnormally high pressure.

The suction pipe 5 is connected to a fuel pipe 104 (low-pressure pipe) that supplies fuel from a fuel tank 103 of the vehicle. . The fuel that has passed through the suction pipe 5 reaches the suction port 3k of the electromagnetic suction valve mechanism 3 via a damper 9, which is a pressure pulsation reduction mechanism, and a suction passage 10d (low-pressure fuel passage).

When the plunger 2 moves in the direction of the cam 91 (downward) and is in the intake stroke, the volume of the pressurization chamber 11 increases and the fuel pressure in the pressurization chamber 11 decreases. In this stroke, when the fuel pressure in the pressurizing chamber 11 becomes lower than the pressure in the intake port 3k, the intake valve 3b is separated from the intake valve seat portion 3a and becomes an open state. Fuel flows into the pressure chamber 11 through the opening of the intake valve 3b.

After the plunger 2 completes the suction stroke, the plunger 2 turns to ascending motion and shifts to the ascending stroke. Here, the electromagnetic coil 3g remains in a non-energized state, and no magnetic biasing force acts between the magnetic core 3e and the anchor 3h. The rod biasing spring 3m is set to have a necessary and sufficient biasing force to keep the intake valve 3b open in a non-energized state. The volume of the pressurization chamber 11 decreases as the plunger 2 compresses. In this state, the fuel that has once been sucked into the pressurization chamber 11 flows through the opening of the intake valve 3b in the open state again into the intake passage. Since the pressure is returned to 10d, the pressure in the pressurizing chamber does not rise. This stroke is called a return stroke.

In this state, when a control current is supplied from the ECU 101 to the electromagnetic suction valve mechanism 3, current flows through the terminal 16 to the electromagnetic coil 3g. When a current flows through the electromagnetic coil 3g, a magnetic attractive force acts between the magnetic core 3e and the anchor 3h. 3e and anchor 3h collide with each other on the magnetic attraction surface. At this time, the anchor 3h moves the rod 3i away from the intake valve 3b via the rod collar 3j.

After that, the intake valve 3b is closed by the urging force of the intake valve urging spring 3l and the fluid force due to the fuel flowing into the intake passage 10d. After the valve is closed, the fuel pressure in the pressurizing chamber 11 rises with the upward motion of the plunger 2, and when it exceeds the pressure at the fuel discharge port 12a, the high pressure fuel is discharged through the discharge valve mechanism 8, and the high pressure fuel is discharged to the common rail. 106. This stroke is called a discharge stroke.

The upward stroke from the lower starting point to the upper starting point of the plunger 2 consists of a return stroke and a discharge stroke. By controlling the timing of energization of the electromagnetic coil 3g of the electromagnetic intake valve mechanism 3, the amount of high pressure fuel to be discharged can be controlled. If the timing of energizing the electromagnetic coil 3g is advanced, the proportion of the return stroke in the upward stroke becomes small and the proportion of the discharge stroke becomes large. That is, less fuel is returned to the intake passage 10d, and more fuel is discharged at high pressure. On the other hand, if the energization timing is delayed, the proportion of the return stroke in the ascending stroke is increased and the proportion of the discharge stroke is decreased. That is, more fuel is returned to the intake passage 10d, and less fuel is discharged at high pressure. The timing of energization of the electromagnetic coil 3g is controlled by a command from the ECU 101. FIG.

In this embodiment, the configuration of a normally open solenoid valve has been described as an example of the electromagnetic suction valve mechanism 3. However, any solenoid valve structure that can be opened and closed electromagnetically will have the same effect on the low pressure section, which will be described later. It is possible to apply a damper cover structure that

The discharge valve mechanism 8 shown in FIG. 3 includes a discharge valve seat 8a, a discharge valve 8b that contacts and separates from the discharge valve seat 8a, a discharge valve spring 8c that biases the discharge valve 8b toward the discharge valve seat 8a, and a discharge valve 8b. It is composed of a discharge valve stopper 8d that determines the stroke (movement distance) and a plug 8e that blocks leakage of fuel to the outside. A discharge valve chamber 8g is formed on the secondary side of the discharge valve 8b (opposite side to the pressurizing chamber 11). 12a.

When there is no fuel differential pressure between the pressure chamber 11 and the discharge valve chamber 8g, the discharge valve 8b is pressed against the discharge valve seat 8a by the biasing force of the discharge valve spring 8c and closed. Only when the fuel pressure in the pressure chamber 11 becomes higher than the fuel pressure in the discharge valve chamber 8g does the discharge valve 8b open against the biasing force of the discharge valve spring 8c. When the discharge valve 8b is opened, the high-pressure fuel in the pressure chamber 11 is discharged to the common rail 106 (see FIG. 1) through the discharge valve chamber 8g and the fuel discharge port 12a. With the configuration described above, the discharge valve mechanism 8 functions as a check valve that restricts the flow direction of the fuel.

A damper 9 is installed in the low-pressure fuel chamber 10 shown in FIG. When the fuel once flowing into the pressurization chamber 11 is returned to the intake passage 10d through the intake valve 3b in the open state again for capacity control, the fuel returned to the intake passage 10d causes the low-pressure fuel chamber 10 to Pressure pulsation occurs. However, the damper 9 provided in the low-pressure fuel chamber 10 is formed of a metal diaphragm damper in which two corrugated disc-shaped metal plates are pasted together on the outer periphery thereof and an inert gas such as argon is injected into the interior. Pressure pulsation is absorbed and reduced by expansion and contraction of this metal damper.

The plunger 2 has a large diameter portion 2a and a small diameter portion 2b, and the volume of the pre-chamber 7a increases and decreases as the plunger reciprocates. The auxiliary chamber 7a communicates with the low-pressure fuel chamber 10 through a communication passage 10e (FIG. 3). Fuel flows from the auxiliary chamber 7a to the low-pressure fuel chamber 10 when the plunger 2 is lowered, and from the low-pressure fuel chamber 10 to the auxiliary chamber 7a when the plunger 2 is raised.

As a result, the flow rate of fuel into and out of the fuel pump 100 during the intake stroke or return stroke of the fuel pump 100 can be reduced, and the pressure pulsation generated inside the fuel pump 100 can be reduced.

Details around the damper cover will be described with reference to FIG. 4 is a sectional view showing a section around the damper cover of FIG. 2. FIG.

The body 1 has an annular protrusion 1b at its upper end, and a recess 1c is formed radially inside the protrusion 1b. The damper 9 is sandwiched between an upper support member 21 and a lower support member 22 and fixed inside the damper cover 20 .

The damper cover 20 has a top surface portion 20T and side surface portions 20S extending downward from the outer peripheral edge portion of the top surface portion 20T. The top surface portion 20T is composed of a stepped surface (an upper step portion 20T1, a middle step portion 20T2, and a lower step portion 20T3) having steps in the vertical direction (the axial direction of the plunger 2).

The upper support member 21 is pressed downward by the pressing portion 20 b of the damper cover 20 . The pressing portion 20b is configured by a surface of the lower portion 20T3 of the damper cover 20 facing the body 1 (a surface facing downward). Therefore, the portion of the damper cover 20 that abuts on the upper support member 21 is limited to a partial range of the top surface portion 20T, and the fuel passage around the upper support member 21 can be easily secured. Further, the upper support member 21 is positioned in the radial direction (horizontal direction) in the low-pressure fuel chamber 10 by contacting the inner peripheral surface of the side surface portion 20S of the damper cover 20 with the outermost peripheral edge 21a.

The lower support member 22 includes a side surface portion 22S extending along the inner peripheral surface of the side surface portion 20S of the damper cover 20 and the inner peripheral surface of the annular convex portion 1b of the body 1, and radially inward from the upper end portion of the side surface portion 22S. and a circular ring portion 22C formed by bending the . The outer peripheral surface of the side surface portion 22S of the lower support member 22 is press-fitted and fixed to the inner peripheral surface of the side surface portion 20S of the damper cover 20, and is also press-fitted and fixed to the inner peripheral surface of the convex portion 1b of the body 1. .

The upper support member 21 and the lower support member 22 are respectively a second support member and a first support member, and since they sandwich the damper 9 between them, they also serve as a second clamping member and a first clamping member. The damper 9 is supported on the lower support member 22, and is sandwiched between the lower support member 22 and the upper support member 21 by receiving the pressing force from the upper support member 21. Therefore, the lower support member 22 functions as a support member. , and the upper support member 21 is sometimes called a pressing member.

The press-fitting position (press-fitting range) of the lower support member 22 with respect to the damper cover 20 is 20a, and the press-fitting position (press-fitting range) of the lower support member 22 with the projection 1b is 1a. The press-fitting portion (first press-fitting portion) 20a and the press-fitting portion (second press-fitting portion) 1a are formed between the outer peripheral surface of the side surface portion 22S of the lower support member 22, the inner peripheral surface of the side surface portion 20S of the damper cover 20, and the convex portion 1b. Since it is configured between the inner peripheral surface, it is configured on the same cylindrical surface.

In this case, the press-fitting portion (first press-fitting portion) 20a and the press-fitting portion (second press-fitting portion) 1a correspond to the press-fitting direction (vertical direction) between the lower support member (support member) 22, the body 1, and the damper cover (cover portion) 20. direction). It is preferable that at least one of the upper support member 21 and the lower support member 22 is elastically deformed to apply an urging force between the damper cover 20, the upper support member 21 and the damper 9 to hold them.

Specifically, the press-fit portion (first press-fit portion) 20 a is formed between the outer peripheral surface of the lower support member (support member) 22 and the inner peripheral surface of the damper cover (cover portion) 20 . A press-fit portion (second press-fit portion) 1 a is formed between the outer peripheral surface of the lower support member 22 and the inner peripheral surface of the body 1 .

More specifically, the body 1 has an annular projection 1b at the end (part) covered by the damper cover 20. As shown in FIG. The damper cover 20 has a top surface portion 20T and side surface portions 20S extending downward (toward the body 1) from the outer peripheral edge portion of the top surface portion 20T. The lower support member 22 includes a side surface portion 22S extending along the inner peripheral surface of the side surface portion 20S of the damper cover 20 and the inner peripheral surface of the convex portion 1b of the body 1, and a top surface portion 20T at the side surface portion 22S of the lower support member 22. and an annular portion 20</b>C formed by bending radially inward from the end on the side of the .

The press-fit portion 20 a is formed between the outer peripheral surface of the side surface portion 22</b>S of the lower support member 22 and the inner peripheral surface of the side surface portion 20</b>S of the damper cover 20 . The press-fit portion 1a is formed between the outer peripheral surface of the side surface portion 22S of the lower support member 22 and the inner peripheral surface of the annular convex portion 1b.

That is, the fuel pump 100 of this embodiment includes a body 1, a damper cover (cover portion) 20 that covers the body 1, a lower support member (support member) 22 that supports the damper (accommodated portion) 9, and a lower support member. A press-fit portion (first press-fit portion) 20a formed between the member 22 and the damper cover 20 to fix the lower support member 22 to the damper cover 20, and a lower support member formed between the lower support member 22 and the body 1. A press-fitting portion (second press-fitting portion) 1a for fixing the lower support member 22 to the body 1 is formed on the same surface (the outer peripheral surface portion of the side surface portion 22S) as the surface on which the press-fitting portion 20a of 22 is formed.

Further, a damper (damper mechanism) 9 is disposed on the inner peripheral side of the damper cover (cover portion) 20, and the lower support member (support member) 22 is press-fitted (first press-fit portion) 20a to move the damper 9 to the damper cover. 20 (the back surface of the top surface portion 20T).

The lower end portion of the side surface portion 20S of the damper cover (cover portion) 20 (the lower end portion of the side surface portion 20S) and the upper end portion of the convex portion 1b of the body 1 (the upper end portion of the convex portion 1b) are arranged so as to be in contact with each other. Abutting portion (contact surface) BU is formed and welded at the location of the abutting portion BU. In this case, the press-fitting portion (first press-fitting portion) 20a and the press-fitting portion (second press-fitting portion) 1a are arranged in the press-fitting direction (vertical direction) between the lower support member (support member) 22 and the body 1 and the damper cover 20. It is formed up to a range approximately the same distance from the abutting portion (contact surface) BU between the cover 20 and the body 1 .

In this embodiment, the press-fit portion 20a is in the range indicated by l20, the press-fit portion 1a is in the range indicated by l1, and l20 and l1 are equal (l20=l1). As a result, the fixing force of the press-fit portion 20a of the lower support member 22 to the damper cover 20 and the fixing force of the press-fit portion 1a to the body 1 can be made equal, and the damper cover 20 and the body 1 are stably fixed. can do.

FIG. 4 shows an image of the melted portion of the welded portion W by a dashed line. Since the size of the welded portion W varies depending on the welding conditions, the image in this figure is shown as an example. A welded portion W for fixing the damper cover (cover portion) 20 and the body 1 is provided radially outward of the lower support member (support member) 22 . That is, welding is performed by irradiating the welding portion W with a laser from the radially outer side of the damper cover 20 and the body 1 . This welded portion W is formed on the contact surface between the lower end of the damper cover 20 (the lower end of the side surface portion 20S) and the upper end of the body 1 (the upper end of the convex portion 1b). It is provided so as to straddle.

FIG. 5A is a cross-sectional view of the abutting portion BU before welding, and FIGS. 5B and 5C are cross-sectional views showing the penetration shapes after the first and second rounds of welding, respectively.

A chamfer 30a is formed along the entire circumference of the inner peripheral surface of the lower end portion of the side surface portion 20S of the damper cover 20, which contacts the convex portion 1b of the body 1 at the abutting portion BU before welding. A chamfer 30b is formed on the inner peripheral surface of the convex portion 1b of the body 1, which contacts the lower end portion of the side surface portion 20S of the damper cover 20. As shown in FIG. As a result, a gap BG1 formed by the chamfers 30a and 30b at the contact surfaces of the body 1 and the damper cover 20 is formed on the inner peripheral surface of the abutting portion BU.

Also, when laser welding the butted portion BU, a program is used in which two rounds are welded continuously after one round of welding. During the first round of welding, the metal that reaches the melting point and becomes liquid flows into the gap BG1 shown in FIG. 5A, solidifies to fill the gap BG1, and forms a penetration shape 40 shown in FIG. 5B. After the first round of welding is completed, the liquid flows into the gap BG2 remaining in the first round of welding, and then cools again, reaches the freezing point, and solidifies during the second round of welding. As a result, the penetration shape 41 after the second round of welding shown in FIG. 5C is divided into upper and lower bifurcations, and a larger bonding area between the body 1, the damper cover 20, and the lower support member 22 is ensured compared to the one-round welding. As a result, the damper cover can be securely fixed to the body 1 by increasing the coupling force.

In addition, the gaps BG1 and BG2 also serve to confine spatter generated during welding so that it does not reach the fuel passage, thereby preventing the spatter from scattering inside the fuel pump.

As shown in FIG. 4, a gap g is provided between the lower end surface of the lower support member 22 and the body 1 in this embodiment. That is, the lower end portion (the end portion on the side opposite to the top surface) of the side surface portion 20S of the damper cover (cover portion) 20 is in contact with the upper end portion (the end portion on the damper cover 20 side) of the annular convex portion 1b of the body 1. , the lower end portion of the side surface portion 22S of the lower support member (support member) 22 is arranged so as to be out of contact with the bottom surface 1d of the recess formed inside the annular protrusion 1b. This gap g prevents the lower support member 22 from being pushed in while being in contact with the bottom surface 1d of the recess 1c formed by the protrusion 1b of the body 1 when the damper cover 20 is assembled. 22 can be prevented from generating excessive stress. However, if the upper support member 21 or the lower support member 22 can be sufficiently elastically deformed, it is practical to design without providing a gap between the lower end surface of the lower support member 22 and the body 1 .

In this embodiment, an example in which the damper cover 20 is fixed to the body 1 is described, but this embodiment can also be applied to the case of fixing other covers to the body 1 . A member including other covers, without being limited to the damper cover 20, is called a cover portion. A part that is housed in the body 1 and covered with the cover part is called a housed part (a part corresponding to the damper 9 in this embodiment).

The main features of this embodiment can also be summarized as follows.

As shown in FIG. 4, the high-pressure fuel supply pump 100 includes a damper 9 that reduces pressure pulsation, a lower support member 22 that supports the damper 9, a damper cover 20 that covers the damper 9 and the lower support member 22, a body 1 and laser welding marks (welded portion W) formed on the contact surface (butting portion BU) between the damper cover 20 and the body 1 .

As shown in FIG. 5C , the weld trace has a penetration shape 41 bifurcated in the thickness direction of the lower support member 22 . Thereby, the coupling force between the body 1, the damper cover 20 and the lower support member 22 can be improved. As a result, the robustness of the high-pressure fuel supply pump 100 is improved against an increase in fuel pressure.

As shown in FIGS. 5B and 5C, the weld marks consist of a first welded portion W1 by 360° circumferential laser welding and a second welded portion W2 by two-circumference welding in a part or all of the circumferential direction. be done. As a result, when a part of the circumferential direction is welded twice, the manufacturing cost can be reduced, and when the entire circumferential direction is welded twice, the bonding force can be further improved. .

As shown in FIG. 4 , the first press-fit portion (press-fit portion 20 a ) is formed between the lower support member 22 and the damper cover 20 to fix the lower support member 22 to the damper cover 20 . The second press-fitting portion (press-fitting portion 1a) is formed between the lower support member 22 and the body 1, and is formed on the same surface as the first press-fitting portion (press-fitting portion 20a). is fixed to body 1. The first press-fitting portion (press-fitting portion 20a) and the second press-fitting portion (press-fitting portion 1a) are arranged at different positions in the press-fitting direction. This makes it possible to easily press-fit and fix.

As shown in FIG. 4, the first press-fitting portion (press-fitting portion 20a) and the second press-fitting portion (press-fitting portion 1a) are substantially in the same press-fitting direction from the contact surface (butting portion BU) between the damper cover 20 and the body 1. Formed by the range of distances (l20, l1). Thereby, the fixing force by the first press-fitting portion (press-fitting portion 20a) and the second press-fitting portion (press-fitting portion 1a) can be made uniform.

As shown in FIG. 5A, the body 1 has an annular projection 1b. The damper cover 20 has a side portion 20S in contact with the convex portion 1b. The lower support member 22 contacts the inner peripheral surfaces of the convex portion 1b and the side portion 20S. The welding mark is formed on the contact surface (butting portion BU) between the side surface portion 20S and the convex portion 1b shown in FIG. 5A, and is bifurcated inside the lower support member 22 (FIG. 5C). As a result, the bonding force between the convex portion 1b, the side portion 20S and the lower support member 22 can be improved.

As shown in FIG. 5A, a first chamfer 30a is provided on the inner peripheral side and the contact surface (butting portion BU) side of the side surface portion 20S, and a second chamfer is provided on the inner peripheral side and the contact surface side of the convex portion 1b. 30b. A first space SP1 surrounded by the first chamfer 30a, the contact surface and the lower support member 22 is wider than a second space SP2 surrounded by the second chamfer 30b, the contact surface and the lower support member 22. FIG. As a result, the weld marks are formed so as to extend to the first space SP1 in the first round of laser welding, and are formed to extend to the second space SP2 in the second round of laser welding. In this embodiment, the cross sections of the first chamfer 30a and the second chamfer 30b are curved (R-shaped), but they may be straight.

In addition, the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments are detailed descriptions for easy understanding of the present invention, and are not necessarily limited to those having all the configurations. In addition, it is possible to replace a part of the configuration of the embodiment with another configuration, and it is possible to add another configuration to the configuration of the embodiment. There may be.

(1). A high-pressure fuel pump in which a damper mechanism is arranged on an inner peripheral side of a body, a damper cover, and the damper cover portion, wherein the contact surface between the upper end portion of the body and the lower end portion of the damper cover is provided with a welding mark obtained by welding with a laser. 2. A high-pressure fuel pump, wherein, when the body is axially cross-sectioned, the penetration shape of the weld marks is bifurcated in the thickness direction of the lower support member that supports the damper mechanism.

(2). The high-pressure fuel pump according to (1), wherein the welding portion between the body and the damper cover portion is laser-welded all around in a circumferential direction of 360°, and a part is welded twice.

(3). In the fuel pump of (2), a first press-fit portion is formed between the support member and the cover portion to fix the support member to the cover portion, and a first press-fit portion is formed between the support member and the body. and a second press-fit portion formed on the same surface of the support member on which the first press-fit portion is formed, for fixing the support member to the body.

(4). In the fuel pump of (3), the first press-fitting portion and the second press-fitting portion are arranged at different positions in the press-fitting direction of the support member and the body and the cover portion.

(5). In the fuel pump of (4), the first press-fitting portion and the second press-fitting portion are formed to a range of approximately the same distance in the press-fitting direction from the contact surface between the cover portion and the body in the press-fitting direction. Fuel pump.

In the present embodiment, by chamfering the end face of the welded portion of the damper cover and the two parts of the body, it is possible to bifurcate the penetration shape during welding.

According to (1) to (5), the joint between the cylindrical member, the damper cover, and the body has a two-branched penetration shape, thereby increasing the joint area and the joint strength of the tubular member, the damper cover, and the body. Therefore, it is possible to provide a high-pressure fuel supply pump that prevents the damper cover from being displaced with respect to the body and that achieves low noise, and a method of manufacturing the same.

Reference Signs List 1 Body 1a Second press-fit portion 2 Plunger 3 Electromagnetic intake valve mechanism 3h Anchor 3i Rod 4 Relief valve mechanism 5 Intake pipe 6 Cylinder 7 Seal holder 8... Discharge valve mechanism, 9... Damper, 10a... Low-pressure fuel suction port, 11... Pressure chamber, 12... Discharge joint, 13... Plunger seal, 20... Damper cover, 20a... First press-fit portion, 21... Upper support member , 22... Lower support member 30a... Chamfering of the lower end surface of the damper cover 30b... Chamfering of the upper end surface of the body 40... Penetration shape of the first round 41... Penetration shape of the second round of welding BG1... First round BG2: weld gap during second round welding, W: welded part, BU: abutting part (contact surface)

Claims (7)

a damper for reducing pressure pulsations;
a lower support member that supports the damper;
a damper cover that covers the damper and the lower support member;
body and
laser welding marks formed on the contact surface between the damper cover and the body,
The high-pressure fuel supply pump, wherein the weld mark has a penetration shape bifurcating in the thickness direction of the lower support member. A high-pressure fuel supply pump according to claim 1,
The weld marks are
A first welded portion by circumferential 360° all-around laser welding;
and a second welded portion formed by welding a part or all of the circumference in two circumferences. A high-pressure fuel supply pump according to claim 2,
a first press-fit portion formed between the lower support member and the damper cover for fixing the lower support member to the damper cover;
a second press-fit portion formed between the lower support member and the body, formed on the same surface as the first press-fit portion, and fixing the lower support member to the body; A high pressure fuel supply pump characterized by: A high-pressure fuel supply pump according to claim 3,
The first press-fit portion and the second press-fit portion are
A high-pressure fuel supply pump, characterized by being arranged at different positions in a press-fitting direction. A high-pressure fuel supply pump according to claim 4,
The first press-fitting portion and the second press-fitting portion are
A high-pressure fuel supply pump, wherein the high-pressure fuel supply pump is formed within a range of substantially the same distance in the press-fitting direction from the contact surfaces of the damper cover and the body. A high-pressure fuel supply pump according to claim 1,
The body has an annular projection,
The damper cover has a side surface portion in contact with the convex portion,
the lower support member is in contact with inner peripheral surfaces of the convex portion and the side portion;
The weld marks are
formed on the contact surface between the side surface portion and the convex portion,
A high-pressure fuel supply pump, characterized in that it branches into two inside the lower support member. A high-pressure fuel supply pump according to claim 6,
Having a first chamfer on the inner peripheral side of the side surface portion and on the contact surface side,
Having a second chamfer on the inner peripheral side of the convex portion and on the contact surface side,
A first space surrounded by the first chamfer, the contact surface, and the lower support member is wider than a second space surrounded by the second chamfer, the contact surface, and the lower support member. high pressure fuel supply pump.

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