JP7126696B2 - pulsation damper - Google Patents

Description

The present invention relates to a pulsation damper, and more particularly to a pulsation damper capable of effectively reducing pulsation generated in a fuel pump.

In conventional high-pressure fuel pumps, there is a pulsation damper that absorbs and reduces the pulsation of the fluid sucked into the pressurization chamber from the intake passage by a diaphragm damper provided in the fuel chamber that communicates with the pressurization chamber of the housing body. known (see, for example, Patent Document 1).

2. Description of the Related Art In recent years, there has been a growing demand for vehicles to reduce fuel consumption and increase vehicle interior space. However, when the size of the fuel chamber is reduced in accordance with the downsizing of the fuel pump, the mounting of the pulsation damper housed therein becomes a problem.

Patent No. 5664604 specification

In a pulsation damper such as that described in Patent Document 1, four claws are raised radially outward from a support made of a metal plate that supports a diaphragm damper. is elastically deformed by pressing against the ceiling of the diaphragm, and the elastic force is used to support the diaphragm damper. According to such a structure, if the fuel chamber is simply made smaller, the diameter of the support must also be made smaller.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a pulsation damper that is small in size and that can secure an appropriate supporting force for the diaphragm damper.

To achieve the above object, the pulsation damper of the present invention is a pulsation damper housed in a case,
a diaphragm damper containing gas inside;
a support disposed between the case and the diaphragm damper and holding the diaphragm damper;
The support includes an annular holding portion that is provided on the peripheral edge portion and holds the peripheral edge portion of the diaphragm damper, a central contact portion that is provided on the central portion and contacts the case, and a center contact portion that is centered on the central contact portion. and a plurality of elastically deformable beams defined by a plurality of openings annularly formed between the annular holding portion and the central abutment portion, each having one end connected to the annular holding portion. and a beam portion held by and the other end held by the contact portion ,
The central contact portion is provided at a position where the pulsation damper comes into contact with a case projection formed on the inner wall of the case when the pulsation damper is accommodated in the case.
It is characterized by

ADVANTAGE OF THE INVENTION According to this invention, the pulsation damper which can ensure the suitable support force of a diaphragm damper, although it is small, can be provided.

1 is a side view of a pulsation damper 10 according to a first embodiment of the invention; FIG. 2 is a perspective view showing an exploded configuration of the pulsation damper 10; FIG. (a) is a top view of the first support 11, and (b) is a side view of the first support 11. FIG. FIG. 2 is a cross-sectional view showing a state in which the pulsation damper 10 is attached to the case 15; FIG. 5 is a side view of a pulsation damper 20 according to a second embodiment of the invention; 2 is a perspective view showing an exploded configuration of the pulsation damper 20; FIG. (a) is a top view of the first support 21, and (b) is a side view of the first support 21. FIG. FIG. 3 is a cross-sectional view showing a state in which the pulsation damper 20 is attached to the case 15; FIG. 8 is a side view of a pulsation damper 30 according to a third embodiment of the invention; 3 is a perspective view showing an exploded configuration of the pulsation damper 30. FIG. FIG. 3 is a cross-sectional view showing a state in which the pulsation damper 30 is attached to the case 15; FIG. 11 is a cross-sectional view showing a state in which a pulsation damper 40 according to a fourth embodiment of the present invention is attached to a case 15;

(First embodiment)
FIG. 1 is a side view of a pulsation damper 10 according to a first embodiment of the invention. FIG. 2 is a perspective view showing an exploded configuration of the pulsation damper 10. FIG.

As shown in both figures, the pulsation damper 10 consists of a first support 11 , a diaphragm damper 12 and a second support 13 . The diaphragm damper 12 here consists of two plate members 12a (only one is shown in FIG. 2). The plate material 12a having a common circular shape is formed by press-working a stainless steel plate, and has a central circular raised portion 12b and an outer peripheral flange portion 12c. The diaphragm damper 12 is formed by arranging plate members 12a facing each other, joining flange portions 12c in contact with each other by welding, and enclosing gas therein.

The second support 13, which is formed in a circular shape by pressing a thin metal plate, has an annular flange portion 13a that supports the diaphragm damper 12, and a tapered portion provided with small openings 13b that are circumferentially arranged at regular intervals. It has a shaped intermediate portion 13c and a short cylindrical portion 13d connected to the tapered intermediate portion 13c. An opening 13e is formed in the lower peripheral edge of the short tubular portion 13d.

3A is a top view of the first support 11, and FIG. 3B is a side view of the first support 11. FIG.

The first support body 11, which is formed in a circular shape by pressing a thin metal plate, includes an annular flange portion 11a, a circular center portion 11b protruding and deviating from the flange portion 11a, and the flange portion 11a and the center portion. and a cylindrical portion 11c connecting with 11b. The central portion 11b and the cylindrical portion 11c constitute an annular holding portion that supports the diaphragm damper 12. As shown in FIG.

The central portion 11b has an annular portion 11e connected to the cylindrical portion 11c and a cross-shaped bridging portion 11f connected to the annular portion 11e. A base portion 11g is provided at the center of the bridging portion 11f, and a truncated cone-shaped support projection (center contact portion) 11h is formed so as to push out the center of the base portion 11g from the back side. The support protrusion 11h may be dome-shaped. It can be said that the bridging portion 11f is formed by radially forming four beam portions 11i on the base portion 11g. In this case, a pair of beam portions 11i extending so as to face each other with the base portion 11g interposed therebetween form a beam whose both ends are supported by the annular portion 11e. A substantially fan-shaped opening 11j is formed in each of the four regions surrounded by the annular portion 11e and the adjacent beam portions 11i of the bridging portion 11f. In other words, the four openings 11j define the inner contour of the annular portion 11e and the contour of the bridging portion 11f.

The four beams 11i have a common shape, and each has a constriction 11k that smoothly narrows from both ends toward the center. By providing a constriction 11k in the central portion of each beam portion 11i, the pulsation damper 10 is easily bent when subjected to a load during assembly. Also, the modulus of elasticity of the bridging portion 11f can be easily adjusted by changing the shape of the constriction 11k.

(Assembly of pulsation damper)
FIG. 4 is a sectional view showing the state where the pulsation damper 10 is attached to the case 15. As shown in FIG. In FIG. 4, the case 15 has a bottomed tubular member 15b with an open upper end 15a, a disk-shaped lid member 15c covering the upper end 15a of the bottomed tubular member 15b, and a bottom wall 15d of the bottomed tubular member 15b. A circular recess 15e and a circular opening 15f are formed in the recess 15e. The opening 15f communicates with a pressurization chamber (not shown). By assembling the bottomed cylindrical member 15b and the lid member 15c, the case 15, which is a part of the fuel pump, for example, is formed.

At the time of assembly, as shown in FIG. 2, the diaphragm damper 12 is arranged between the first support 11 and the second support 13, and the flanges 11a, 12c, and 13a are welded together, as shown in FIG. A pulsation damper 10 is formed. The flange portions 11a, 12c, and 13a do not necessarily have to be welded together, and the diaphragm damper 12 may simply be sandwiched between the first support 11 and the second support 13. FIG.

Furthermore, with the cover member 15c removed from the bottomed cylindrical member 15b, as shown in FIG. Then, the pulsation damper 10 is arranged inside the case 15 . After that, the cover member 15c is attached to the bottomed cylindrical member 15b and sealed by welding or bolts or the like to form the case 15 capable of containing the fuel, and the fuel chamber FR is defined therein.

At this time, the support projection 11h provided on the bridging portion 11f of the first support 11 abuts (faces) the lower surface 15g of the lid member 15c, thereby elastically deforming the beam portion 11i, and the elastic force of the projection 11h causes the pulse to move. The sation damper 10 can be biased downward and held in the case 15 . In this state, the fuel chamber FR communicates with the pressure chamber (not shown) through the opening 15f, and the fuel in the fuel chamber FR comes into contact with the diaphragm damper 12 through the openings 11j, 13e and the small opening 13b. , the effect of reducing the pulsation of the pulsation damper 10 during the operation of the fuel pump is exhibited.

According to the present embodiment, even when the diameter of the first support 11 is relatively small, the bridging portion 11f can ensure a sufficient length of the beam portion 11i, thereby ensuring good elastic characteristics. Further, by adjusting the shape of the constriction 11k of the beam portion 11i, it is possible to impart elastic properties suitable for the diameter of the first support 11 to the bridging portion 11f. The beam portion 11i may extend obliquely from the base portion 11g instead of extending radially from the base portion 11g as described above.

(Second embodiment)
FIG. 5 is a side view of a pulsation damper 20 according to a second embodiment of the invention. FIG. 6 is a perspective view showing an exploded configuration of the pulsation damper 20. As shown in FIG.

As shown in FIG. 6, the pulsation damper 20 consists of a first support 21, a diaphragm damper 12, and a second support 13. As shown in FIG. Since the diaphragm damper 12 and the second support 13 are the same as those in the above-described embodiment, the same reference numerals are assigned to the respective parts, and redundant explanations are omitted.

7A is a top view of the first support 21, and FIG. 7B is a side view of the first support 21. FIG.

The first support body 21, which is formed in a circular shape by pressing a thin metal plate, has an annular flange portion 21a, a circular central portion 21b deviated from the flange portion 21a, the flange portion 21a and the central portion 21b. and a cylindrical portion 21c that connects the

The central portion 21b has an annular portion 21e connected to the cylindrical portion 21c and a cross-shaped bridging portion 21f connected to the annular portion 21e. A substantially diamond-shaped base portion 21g is provided at the center of the bridging portion 21f, and a truncated cone-shaped support protrusion 21h is formed by pushing out the base portion 21g from the back side. It can be said that the bridging portion 21f is formed by radially connecting the four beam portions 21i to the base portion 21g. In this case, a pair of beam portions 21i extending so as to face each other with the base portion 21g interposed therebetween form a beam whose both ends are supported by the annular portion 21e. Four substantially fan-shaped openings 21j are formed so as to be surrounded by the annular portion 21e and the beam portions 21i adjacent to the bridge portion 21f.

The beams 21i have a common shape, and are periodically bent at the center to form a bellows-shaped mountain-valley-shaped portion 21k. When a load is applied during assembly of the pulsation damper 30, the beam portion 21i can be easily bent by providing the mountain-valley portion 21k in the central portion thereof. Also, the elastic modulus of the bridging portion 21f can be easily adjusted by changing the number of the mountain-valley portions 21k. The ridge-and-valley shape portion 21k is not limited to a bellows shape, and may have a shape in which one surface is flat and the other surface is uneven.

(Assembly of pulsation damper)
Since the assembly of the pulsation damper 20 is the same as in the above-described embodiment, redundant description will be omitted.
FIG. 8 is a sectional view showing the pulsation damper 20 assembled to the case 15. As shown in FIG. Since the case 15 is also the same as in the above-described embodiment, it is given the same reference numerals in FIG. 8 and redundant description is omitted.

The pulsation damper 20 assembled as shown in FIG. 5 is shown in FIG. 8 with the cover member 15c removed from the bottomed tubular member 15b, and the short tubular portion 13d of the second support 13 is positioned between the bottomed tubular member 15b. It is arranged in the case 15 so as to fit into the recess 15e. Further, a case 15 capable of containing fuel is formed by attaching a cover member 15c to the bottomed cylindrical member 15b and sealingly joining them by welding or bolts.

At this time, the support projection 21h provided on the bridging portion 21f of the first support 21 abuts (faces) the lower surface 15g of the lid member 15c, thereby elastically deforming the beam portion 21i. The sation damper 20 can be biased downward and held in the case 15 . In this state, the fuel chamber FR communicates with the pressure chamber (not shown) through the opening 15f, and the fuel in the fuel chamber FR comes into contact with the diaphragm damper 12 through the openings 21j, 13e and the small opening 13b. , the effect of reducing the pulsation of the pulsation damper 20 during the operation of the fuel pump is exhibited.

According to the present embodiment, even if the diameter of the first support 21 is relatively small, the provision of the ridge-and-valley shaped portions 21k makes it possible to ensure a sufficient length of the beam portion 21i, thereby ensuring good elastic characteristics. can. Further, by adjusting the number of peaks and valleys of the peak-to-valley shape portion 21k of the beam portion 21i, it is possible to impart elastic properties suitable for the diameter of the first support 21 to the bridging portion 21f.

(Third Embodiment)
FIG. 9 is a side view of a pulsation damper 30 according to a third embodiment of the invention. FIG. 10 is a perspective view showing an exploded configuration of the pulsation damper 30. As shown in FIG.

As shown in FIG. 10, the pulsation damper 30 consists of a first support 11 and a diaphragm damper 32 . The diaphragm damper 32 is formed by welding the flange portion 12c of the single plate member 12a described above to one side of a flat circular plate 33. As shown in FIG. Since the plate member 12a is the same as in the above-described embodiment, redundant description will be omitted. Also, the first support 11 is the same as that of the above-described embodiment, so the same reference numerals are given to the respective parts, and redundant explanations are omitted.

(Assembly of pulsation damper)
At the time of assembly, as shown in FIG. 10, the circular protrusion 12b of the plate member 12a is directed toward the first support 11, and the flanges 11a and 12c (disk 33) are welded together to form the pulsation damper shown in FIG. form 30;

FIG. 11 is a sectional view showing the pulsation damper 30 assembled to the case 15. As shown in FIG. Regarding the case 15, instead of providing openings in the bottom wall 15d of the bottomed cylindrical member 15b, a plurality of openings 15h are formed around the lower surface 15g of the cover member 15c except for the center. Since the main difference is only in the point that the parts are provided, the same reference numerals are given to the common configurations, and redundant explanations will be omitted. The opening 15h similarly communicates with a pressurizing chamber (not shown).

The pulsation damper 30 assembled as shown in FIG. 9 is placed in a state in which the cover member 15c is removed from the bottomed cylindrical member 15b in FIG. and placed in the case 15. Further, a case 15 capable of containing fuel is formed by attaching a cover member 15c to the bottomed cylindrical member 15b and sealingly joining them by welding or bolts.

At this time, the support projection 11h provided on the bridging portion 11f of the first support 11 abuts (faces) the lower surface 15g of the lid member 15c, thereby elastically deforming the beam portion 11i, and the elastic force of the projection 11h causes the pulse to move. The sation damper 30 can be biased downward and held in the case 15 . In this state, the fuel chamber FR communicates with the pressure chamber (not shown) through the opening 15h, and the fuel in the fuel chamber FR comes into contact with the diaphragm damper 12 through the opening 11j and the small opening 13b. The effect of reducing the pulsation of the pulsation damper 30 during the operation of the fuel pump is exhibited.

According to this embodiment, the number of parts can be reduced as compared with the above-described embodiment. Although the pulsation damper 30 is configured using the first support 11 according to the first embodiment, other first supports may be used.

(Fourth embodiment)
FIG. 12 is a cross-sectional view showing the state where the pulsation damper 40 is attached to the case 15. As shown in FIG. Here, the lid member 15c of the case 15 has a case protrusion 15i formed in the center of the lower surface 15g. On the other hand, the pulsation damper 40 does not form support projections on the base 11g of the bridge portion 11f of the first support 11 . Otherwise, it is the same as the embodiment described above.

When the pulsation damper 40 is assembled to the case 15, the case projection 15i provided on the lower surface 15g of the lid member 15c abuts (faces) the base portion 41g of the bridging portion 41f of the first support 41, thereby The portion 41 i is elastically deformed, and the elastic force urges the pulsation damper 40 downward to hold it in the case 15 .

Although representative embodiments of the present invention have been described above using the first to fourth embodiments, it goes without saying that various modifications are possible without departing from the gist of the present invention. For example, although four beams are provided in each of the above-described embodiments, the number of beams may be two or more, and may be either an even number or an odd number. Also, the arrangement of these beams is not limited to being arranged radially from the central portion of the support at equal intervals, and may be arranged in a regular interval pattern. Furthermore, the shape of the entire bridging portion is not limited to the cross shape in the embodiment, and may be, for example, a U shape.

10, 20, 30, 40 Pulsation dampers 11, 21 First supports 11a, 21a Flanges 11f, 21f Bridges 11i, 21i Beams 11h, 21h Support projections 11k Constrictions 21k Mountain-and-valley portions 12, 32 Diaphragm dampers 13 Second support 15 Case 15i Case protrusion 33 Disk

Claims (6)

A pulsation damper housed in a case,
a diaphragm damper containing gas inside;
a support disposed between the case and the diaphragm damper and holding the diaphragm damper;
The support includes an annular holding portion that is provided on the peripheral edge portion and holds the peripheral edge portion of the diaphragm damper, a central contact portion that is provided on the central portion and contacts the case, and a center contact portion that is centered on the central contact portion. a plurality of elastically deformable beams defined by a plurality of openings annularly formed between the annular holding portion and the central abutment portion, each having one end connected to the annular holding portion; and the other end of which is held by the abutting portion.death,
The central contact portion is provided at a position where the pulsation damper contacts a case projection formed on the inner wall of the case when the pulsation damper is housed in the case.
A pulsation damper characterized by: 2. The pulsation damper according to claim 1, further comprising a support protrusion formed on said central contact portion and contacting said case. 3. The pulsation damper according to claim 1, wherein the beam has a constriction at least in part. 3. The pulsation damper according to claim 1, wherein at least a portion of the beam portion has a peak-and-valley shape. 5. The pulsation damper according to claim 4 , wherein the beam has a bellows shape. The pulsation damper according to any one of claims 1 to 5 , wherein the support is arranged so as to cover one side of the diaphragm damper.

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