JP2002130080A - Injector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an injector at low manufacturing cost. SOLUTION: This injector comprises a body, a sheet 25 fixed to a tip of the body, and a valve having a ball on its tip and an armature on its rear end, and reciprocated and slid in the body. Plural continuous projection parts are formed on the sheet 25 in parallel with the sliding direction of the valve, and projecting tip parts 25h are pressurized and deformed by casting work to form a slide face 25j. The slide face 25j formed by casting the tip parts 25h are manufactured with high accuracy in size, and the cost can be reduced by applying the casting work.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an injector for an internal combustion engine. In particular, the present invention relates to a technique for reducing the cost of an injector.

[0002]

2. Description of the Related Art An example of a conventional injector is
This will be described with reference to FIGS. FIG. 1 is a sectional view of the injector. FIG. 2 is a sectional view of the sheet. FIG.
FIG. 2 is a plan view of the seat, which is a view of FIG. 2 as viewed from above.
FIG. 4 is a diagram showing a cross-sectional view in which a part of the valve is cut away. FIG. 5 is a cross-sectional view showing a state where the ball at the tip of the valve is inserted into the seat. As shown in FIG. 1, a substantially cylindrical body 136 is fixed to the front end (the lower side in FIG. 1; the upper side in the figure is the rear end; the same applies hereinafter) of the housing 122 of the injector 110. Further, a sheet 125 is fixed to the tip of the body 136. This sheet 125 is manufactured by forging. As shown in FIG. 2 and FIG.
25 has a cylindrical shape, and has a cylindrical hole 12 from the rear end side.
5b, and a columnar hole 125c having a smaller diameter than the hole 125b is formed on the distal end side. A conical surface 125d is formed at the distal end side of the cylindrical hole 125c, and an opening 125a is formed at the distal end of the conical surface 125d.
Is open. A plurality of fuel passages 125f extending in the axial direction are formed around the hole 125c.

[0003] As shown in FIG.
Is composed of a cylindrical shaft portion 132c, an armature 132b having a cylindrical outer shape at the rear end side of the shaft portion 132c, and a spherical ball 132a fixed to the front end of the shaft portion 132c. This armature 132b is also manufactured by forging. As shown in FIG. 5, the inner surface of the hole 125c of the seat 125 is
The ball 132a functions as a slide surface for guiding the ball 132a in the axial direction of the injector 110. That is, as the valve 132 reciprocates, the ball 132a slides in the axial direction while being guided by the hole 125c of the seat 125. Valve 1
32 moves forward (toward the front end side; the opposite side is referred to as reverse movement).
Then, the ball 132a abuts on the conical surface 125d of the seat 125 at the portion of 125e, and the opening 1
25a is closed.

[0004] At the rear end of the body 136, a ring 137 having a cylindrical rear end and a brim-shaped front end is fixed to the housing 122 as shown in FIG. The armature 132b of the valve 132 is
With the reciprocation of 2, the ring 137 is guided by the inner surface of the ring 137 (hereinafter, referred to as a body slide surface 137a) and slides in the axial direction. From the outside of the injector 110, pressurized fuel is supplied to the fuel supply port 126, and the fuel supply port 126 and the sheet 125 communicate with each other through a passage. The valve 132 reciprocates by the magnetic force generated by the solenoid 134 and the spring force of the spring 127. In a state where the valve 132 is advanced, the seat 1 is moved as described above.
The 25 opening 125a is closed, and the opening 125a is opened when the vehicle moves backward, and fuel is injected.

[0005] As described above, the ball 132a fixed to the front end of the valve 132 and the armature 132b formed at the rear end are respectively provided on the inner surface of the cylindrical hole 125c of the seat 125 and the body slide surface 137a. It is guided and slides in the axial direction. In this case, the ball 13
2a, inner surface of hole 125c, and armature 132b
It is required that the gap between the body and the body slide surface 137a is small. If the gap is large, when the valve 132 reciprocates, the valve 132 moves eccentrically (moves while rattling), and the ball 132a and the hole 1 move.
This is because the inner surface of the armature 25c, the armature 132b, and the body slide surface 137a hit each other, causing scratches. The inner surface of the hole 125c and the ball 13
If the gap of 2a is large, the ball 132a and the seat 125
Does not completely contact with the conical surface 125d, and the opening 125a is not closed, so that fuel leakage occurs. Thus, the injector is required to have a small gap between the valve and the seat and between the valve and the body. As described above, the sheet and the armature are manufactured by forging. However, there is a limit in obtaining high dimensional accuracy for forging from the characteristics of the processing, and the above-mentioned gap requirement cannot be satisfied. For this reason, in the prior art injector, after the sheet and the armature were manufactured by forging, the inner surface of the sheet and the outer surface of the armature were further ground by machining to improve dimensional accuracy, and a small gap was secured. .

[0006]

However, in a slide portion of a valve, a seat for guiding the valve, or the like, it is necessary to perform further mechanical grinding after forging, which requires labor and time.
This has led to an increase in processing costs.

The present invention has been made to solve such a problem, and an object of the present invention is to provide an injector with low manufacturing cost.

[0008]

The injector according to claim 1, wherein the injector has a body, a seat fixed to a tip of the body, and a valve that reciprocates in the body. In the valve guide portion of the seat, a plurality of continuous convex shapes are formed in a sliding direction of the valve, and a tip surface of the convex shape is deformed under pressure by forging to form a slide surface. Features. According to the injector, a plurality of continuous convex shapes (ridge shapes) are formed in the valve guide portion of the seat in the valve sliding direction,
The portion formed by pressurizing and deforming (crushing) the tip of the convex shape by forging is used as a sliding surface with the valve. As described above, when only the tip portion of the convex shape is deformed under pressure by forging, the dimension of the deformed portion (that is, the slide surface) can be manufactured with high accuracy. The reason that the dimensions of the slide surface can be manufactured with high precision is
This is because only the top of the convex shape that is easily deformed is forged. On the other hand, for example, even if a simple hole is formed by forging, the amount of deformation during forging of the material is large,
The variation in shape return is large, and it is not possible to form a hole with good yield and high dimensional accuracy. As described above,
Since the dimensions of the slide surface of the seat formed by the forging process are manufactured with high precision, the gap between the valve ball and the ball can be secured to a sufficiently small value. For this reason, there is no need for extra labor and time required for forming a slide surface by performing grinding by machining. Forging can save labor and time required for machining as compared with machining. Therefore, according to the configuration of the present invention, an injector with low manufacturing cost can be obtained.

An injector according to a second aspect of the present invention includes an injector having a body, a valve at a front end, and a valve having an armature at a rear end and reciprocatingly sliding in the body. A plurality of continuous convex shapes are formed in the sliding direction of the valve, and a tip surface of the convex shape is deformed under pressure by forging to form a slide surface. According to the above-described injector, a plurality of convex shapes are formed on the outer surface of the valve armature in the valve sliding direction, and the tip of the convex shape is pressurized and deformed by forging, and the formed portion is defined as the body. The slide surface. The sliding surface of the armature formed by such forging is
Since it is manufactured with high dimensional accuracy, the gap between the body and the armature can have a sufficiently small value. The reason that the dimensions of the armature can be manufactured with high precision is the same as in the case of the above-described sheet forging, so that the description is omitted here. The valve armature of a conventional injector has been subjected to further mechanical grinding after forging to secure dimensional accuracy, but in the configuration of the present invention, it is sufficient to perform forging instead of the above-mentioned machining. Dimensional accuracy can be ensured. Forging can save labor and time required for machining as compared with machining, and therefore, according to the configuration of the present invention, an injector with low manufacturing cost can be obtained.

According to a third aspect of the present invention, there is provided an injector comprising a body and a valve reciprocatingly sliding within the body, wherein at least one sliding portion of the valve and the body is provided in a sliding direction of the valve. A plurality of continuous convex shapes are formed, and a tip surface of the convex shape is deformed under pressure by forging to form a slide surface. According to the above-described injector, at least one of the sliding portions formed on the valve and the body has a plurality of convex shapes formed in the sliding direction, and the tip of the convex shape is pressurized by forging. The deformed and formed portion serves as a sliding surface with the body. The slide surface formed by such forging is manufactured with high dimensional accuracy for the same reason as in the case of the forging according to the above-described claims. For this reason, in the configuration of the present invention, a slide surface with sufficient accuracy can be obtained without performing machining. Forging can save labor and time required for machining as compared with machining, and therefore, according to the configuration of the present invention, an injector with low manufacturing cost can be obtained.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The main features of the embodiments of the present invention described later will be described. (Mode 1) A plurality of linear convex shapes are formed at equal intervals in the circumferential direction on the inner surface of the substantially cylindrical hole formed in the seat in parallel with the reciprocating direction of the valve, and the tip of the convex shape is formed. Is formed by pressing and deforming by forging, and the formed portion is used as a sliding surface with the ball. Since this slide surface is formed by forging a tip portion having a convex shape that is easy to deform, it has good dimensional accuracy. When the ball of the valve is inserted into the slide portion of the seat, the valley between the adjacent convex shapes communicates in the axial direction, and the valley functions as a fuel passage. Therefore, there is no need to separately provide a fuel passage unlike the seat of the conventional injector. (Mode 2) On the surface of a cylindrical armature formed at the rear end of the valve, a plurality of linear convex shapes are formed at equal intervals in the circumferential direction in parallel with the reciprocating direction of the valve. The tip portion is formed by pressing and deforming by forging, and the formed portion serves as a sliding surface with the ring. Since this slide surface is formed by forging a top of a convex shape that is easy to deform, it has good dimensional accuracy.

[0012]

Embodiment An injector according to an embodiment of the present invention will be described with reference to FIGS. FIG. 6 is a sectional view of the injector. FIG. 7 is a cross-sectional view of the sheet. FIG. 8 is a top view of FIG. 7 and is a plan view of the seat. FIG. 9 is a cross-sectional view taken along line IX-IX of FIG. 7, and shows the shape of the sheet before and after forging the tip end of the convex shape at the same time. FIG. 10 shows a broken part of the valve,
It is the figure shown as a sectional view. FIG. 11 is a plan view of the valve as viewed from the rear end side. FIG. 12 is a plan view of the armature of the valve, showing the shape before and after forging the convex tip portion at the same time. FIG. 13 is a cross-sectional view showing a state where the ball at the tip of the valve is inserted into the seat.
FIG. 14 is a cross-sectional view taken along line XIV-XIV of FIG. 13 and shows a cross section of a seat and a ball.

The injector 10 includes a housing 22, a body 36, a valve mechanism (valve 32, seat 25, etc.),
It comprises a solenoid 34 for operating the valve 32 and the like. As shown in FIG. 6, a cylindrical cylinder 44 is fixed inside the housing 22 by welding. In the axial direction of the cylinder 44, a fuel passage 44a for passing fuel is formed. A ring 3 having a rear end formed in a cylindrical shape and a front end formed in a flange shape is provided on the front end side of the cylinder 44 so as to cover the outer peripheral surface of the cylinder 44.
7 is fixed by welding. Then, the body 36 is fixed so as to be inserted into the front end side of the housing 22, and further, the seat 25 is fixed by being inserted into the front end side of the body 36. The fixing of the body 36 and the sheet 25 is performed by welding. A shallow cup-shaped orifice 33 is fixed to the front end of the sheet 25 by welding. The orifice 33 is provided with a pair of fuel injection holes 33a at the bottom of the cup shape.

As shown in FIGS. 7 and 8, the outer shape of the sheet 25 is cylindrical, and a cylindrical hole 2 is formed from the rear end side.
5b is open. A substantially cylindrical hole 25k whose diameter is smaller than that of the hole 25b is formed at the tip end side of the cylindrical hole 25b. On the inner surface of the hole 25k, a plurality of linearly convex slide portions 25g parallel to the axial direction of the sheet 25 are formed at equal intervals in the circumferential direction. As shown in FIG. 9, the slide portion 25g is first formed at a height including the tip portion 25h by forging, and is further subjected to pressure deformation (crushing) of the convex tip portion 25h by forging. ) To form a slide surface 25j. The slide surface 25j has a shape circumscribing the outer surface of the cylinder. As described above, the slide surface 25j is formed using the two-step forging process because the fore end of the convex shape 25h, which is easily deformed, is subjected to dimensional accuracy of the slide surface 25j. It is for improving. A conical surface 2 is provided at the tip of the cylindrical hole 25k.
5d is formed, and an opening 25a is formed at the tip of the conical surface 25d.

At the rear end of the seat 25 described above, a body 36 is provided.
The valve 32 is housed inside the inside as shown in FIG. As shown in FIGS. 10 and 11, the valve 32 has a hollow rod-shaped shaft portion 32c and a columnar armature 32 formed integrally with the shaft portion 32c at the rear end side.
and a spherical ball 32a fixed to the tip of the shaft portion 32c. Shaft 32c and armature 3
A cylindrical hole 32e communicating in the axial direction is formed in 2b, and this hole 32e communicates with the outside of the valve 32 by a hole 32d formed in the shaft portion 32c. On the side surface of the substantially columnar armature 32b, a plurality of linearly convex slide portions 32f parallel to the axial direction of the valve 32 are formed at equal intervals in the circumferential direction.
As shown in FIG. 12, this slide portion 32f
Is first formed into a convex shape having a height including 32 g by forging, and furthermore, the tip portion 32 of the convex shape is formed by forging.
The portion g is deformed under pressure to form a slide surface 32h. The slide surface 32h has a shape inscribed in the inner surface of the cylinder. The reason why the slide surface 32h is formed by using the two-stage forging process in this manner is to improve the dimensional accuracy of the slide surface 32h in the same manner as the forging process of the slide surface 25j of the sheet 25 described above. is there.

The valve 32 described above is housed in a body 36, and a sliding surface 32 h of an armature 32 b of the valve 32 is guided to an inner surface of a ring 37. FIG.
As shown in the figure, the ball 32a of the valve 32 is
The sheet 25 is guided to the slide surface 25j. Therefore,
The valve 32 is guided at two places, the ring 37 and the seat 25, and slides in the axial direction of the injector 10. As shown in FIG. 6, a cylindrical adjuster 42 is press-fitted inside the cylinder 44. Adjuster 4
2, a fuel passage 42a is formed in the axial direction. The spring 27 is assembled in a compressed state between the adjuster 42 and the armature 32b of the valve 32. Therefore, a force is applied to the valve 32 to push the distal end of the injector 10 by the spring force of the spring 27. The spring 27 is the valve 3
2 is pressed against the tip end of the injector 10, so that the ball 32 a of the valve 32 comes into contact with the conical surface 25 d of the seat 25. When the ball 32a contacts the conical surface 25d, the opening 25a of the seat 25 is closed. The force with which the ball 32a contacts the conical surface 25d is adjusted by the adjuster 42.
By adjusting the axial press-fitting position.

A solenoid 34 is mounted on the outer periphery of the cylinder 44. The solenoid 34 generates a magnetic force when supplied with power and excited. A connector 49 for supplying electric power to the solenoid 34 from outside the injector 10 is formed in the housing 22, and the solenoid 34 and the connector 49 are connected by an electric passage 49a. Here, the cylinder 44, the body 36, and the armature 32b of the valve 32 are made of a magnetic material, and the ring 37 is made of a non-magnetic material. For this reason, when the solenoid 34 is energized,
The body 36, the armature 32b, a gap between the armature 32b and the cylinder 44, and a magnetic path returning to the solenoid via the cylinder 44 are formed. As a result, the armature 32b
Is attracted to the cylinder 44 by magnetic force, and the valve 3
6 overcomes the spring force of the spring 27 and moves backward to the rear end side of the injector 10, and the rear end of the armature 32b abuts on the front end 44b of the cylinder 44 (since the axial movement distance of the valve 32 is small, FIG. Although not shown,
When the valve 32 is pressed against the seat 25 by the spring 27, there is a gap between the rear end surface of the armature 32b and the front end 44b of the cylinder 44).

As shown in FIG. 6, a pipe (not shown) for supplying fuel to the injector 10 from outside is provided.
An O-ring (O-ring) 43, which is an annular elastic body, that maintains airtightness between the
It is attached so as to be inserted into the outer peripheral surface of the rear end. Further, a stopper ring 45 for holding the O-ring 43 at this position is fitted in a groove provided on the outer periphery of the cylinder 44 at the further rear end side of the O-ring 43 and mounted. At the rear end of the cylinder 44, a fuel supply port 46 is opened, and a strainer 48 is attached so as to be inserted into the fuel passage 44a. The strainer 48 is formed in a mesh shape and has a function of capturing foreign matter contained in the fuel supplied to the injector 10. The fuel supplied from the fuel supply port 46 is supplied to the strainer 48 → the fuel passage 44a of the cylinder 44.
→ The fuel passage 42a of the adjuster → the hole 32e in the axial direction of the valve 32 → the hole 32d of the valve 32 → the seat 25. As shown in FIG. 13 and FIG.
Flows through the valley portion 25n between the adjacent slide portions 25g of the seat 25, and reaches the contact portion 25e between the ball 32a and the conical surface 25d. When the valve 32 advances and the ball 32a and the conical surface 25d are in contact with each other at 25e, the fuel is closed here and the opening 25a is closed. The valve 32 moves backward and the ball 32a
When the conical surface 25d is apart from the fuel, the fuel flows out of the opening 25a.

Finally, the injector 10 according to the present embodiment
The operation of will be briefly described. From the outside of the injector 10, pressurized fuel is supplied to a fuel supply port 46, and this fuel reaches the seat 25 through the inside of the injector. No power is supplied to the connector 49 and the solenoid 3
When the magnet 4 is not excited, the ball 32 a of the valve 32 is in contact with the conical surface 25 d of the seat 25 by the spring force of the spring 27. In this state, the opening 25a of the seat is closed, and no fuel flows out of the seat 25. When electric power is supplied to the connector 49, the solenoid 34 is excited to generate a magnetic force, and the armature 32b of the valve 32 is attracted by the magnetic force, and
Moves backward, and the rear end of the armature 32b contacts the front end 44b of the cylinder 44. When the valve 32 moves backward, the ball 32a at the tip of the valve 32 and the conical surface 25 of the seat 25
A gap is created between d and d. Ball 32a and conical surface 25d
When a gap is formed between the fuel cell and the fuel cell, the fuel flows out of the opening 25a through the gap, and is injected to the outside of the injector 10 from the fuel injection hole 33a of the orifice 33 fixed to the tip end of the opening 25a.

Although the injector according to the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and the present invention can be variously modified and improved based on the knowledge of those skilled in the art. The embodiment can be implemented.

For example, in the above-described embodiment, the ring 37 attached to the body guides the armature 32b of the valve 32. However, the ring 37 is not necessarily required to be a member that guides the valve. Good.

The member forming the sliding surface of the valve 32 does not necessarily have to be the armature 32b.
Any member constituting the valve may be used.

The intervals between a plurality of slide portions are not necessarily equal, and the intervals may not be equal for reasons such as processing convenience.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a prior art injector.

FIG. 2 is a sectional view of the valve.

FIG. 3 is a sectional view of the same sheet.

FIG. 4 is a plan view of the same sheet.

FIG. 5 is a cross-sectional view of a state where a ball is inserted into the seat.

FIG. 6 is a cross-sectional view of the injector according to the embodiment.

FIG. 7 is a sectional view of the same sheet.

FIG. 8 is a plan view of the same sheet.

FIG. 9 is a sectional view taken along line IX-IX of FIG. 7;

FIG. 10 is a sectional view of the same valve.

FIG. 11 is a plan view of the same valve.

FIG. 12 is a plan view of the armature of the valve.

FIG. 13 is a sectional view showing a state where the valve is inserted into the seat.

FIG. 14 is a sectional view taken along line XIV-XIV in FIG. 13;

[Explanation of symbols]

10: injector 22: housing 25: sheet, 25a: opening, 25b: hole, 25g: sliding portion, 25h: convex tip, 25j: sliding surface, 25k: hole, 25m: conical surface, 25n: valley 27: Spring 32: Valve, 32a: Ball, 32b: Armature,
32c: shaft portion, 32d: hole, 32e: hole, 32f: slide portion, 32g: convex tip, 32h: slide surface 33: orifice, 33a: fuel injection hole 34: solenoid 36: body 37: ring 42: adjuster , 42a: fuel passage 43: O-ring 44: cylinder, 44a: fuel passage, 44b: tip of cylinder 45: stopper ring 46: fuel supply port 48: strainer 49: connector, 49a: electric passage 110: injector 122: housing 125: sheet, 125a: opening, 125b: hole, 12
5c: hole, 125d: conical surface, 125e: contact portion, 12
5f: fuel passage 126: fuel supply port 127: spring 132: valve, 132a: ball, 132b: armature, 132c: shaft portion 134: solenoid 136: body 137: ring, 137a: body sliding surface

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Motoyuki Suzuki 1-1-1, Kyowa-cho, Obu City, Aichi Prefecture Inside Ai San Industry Co., Ltd. Address 1 Ai San Industry Co., Ltd. F-term (reference) 3G066 AA01 AB02 BA55 BA61 CC01 CC06U CC14 CC15 CE24

Claims (3)

[Claims] 1. An injector comprising: a body; a seat fixed to a tip of the body; and a valve that reciprocates in the body. An injector characterized in that a continuous convex shape is formed, and a distal end portion of the convex shape is deformed under pressure by forging to form a slide surface. 2. An injector comprising: a body; a valve having a valve body at a front end and an armature at a rear end and sliding back and forth in the body; An injector characterized in that a continuous convex shape is formed, and a tip surface of the convex shape is deformed under pressure by forging to form a slide surface. 3. An injector comprising a body and a valve reciprocatingly sliding in the body, wherein at least one sliding portion of the valve and the body has a plurality of continuous convex shapes in a sliding direction of the valve. The injector is characterized in that a slide surface is formed by pressurizing and deforming the convex tip portion by forging.