JP5310041B2 - Cylinder head gasket - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cylinder head gasket capable of suppressing intrusion of foreign matter into an oil pan or the like by a simple structure without changing a cross sectional area of oil return passages of a cylinder head and a cylinder block. <P>SOLUTION: This cylinder head gasket 10 for sealing between faces of the cylinder head 3 and the cylinder block 2 of an engine 1 opposing each other has an opening part 14A formed therein for communicating oil return passages 3a, 2a formed in the cylinder head 3 and the cylinder head 2, respectively. The opening part 14A is sectioned into first and second regions A1, A2, and the total area of the opening areas of the regions A1, A2 is set to an opening area required for returning oil in the engine 1. One out of the first and second regions A1, A2 has an opening shape in which an oil level gauge 8 can be inserted from the cylinder head 3 side. <P>COPYRIGHT: (C)2010,JPO&amp;INPIT

Description

  The present invention relates to a cylinder head gasket that is interposed between a cylinder head and a cylinder block of an internal combustion engine (engine) and seals between the opposing surfaces of the cylinder head and the cylinder block.

  In the internal combustion engine, a cylinder head gasket is interposed between the cylinder head and the cylinder block in order to seal between the opposed surfaces of the cylinder head and the cylinder block. The cylinder head gasket has a combustion chamber hole provided corresponding to the cylinder of the cylinder block, a bolt hole through which a head bolt for fastening the cylinder head to the cylinder block is inserted, and oil from the cylinder head side is returned to the cylinder block side. A plurality of openings such as an oil return hole and a water hole through which cooling water flows are formed.

  In the internal combustion engine, oil return passages for returning oil supplied to the cylinder head to the oil pan are formed in the cylinder head and the cylinder block, respectively. The oil return passages of the cylinder head and the cylinder block communicate with each other through the oil return hole of the cylinder head gasket. The oil supplied to the cylinder head is guided to the oil return passage after finishing the lubrication of each part, and flows down the oil return passage by its own weight and returned to the oil pan.

  Conventionally, the oil return passages of such cylinder heads and cylinder blocks are also used as passages for inserting oil level gauges (see, for example, Patent Documents 1 to 3). The oil level gauge is inserted, for example, from the outside of a head cover attached to the upper side of the cylinder head, and is inserted into the internal combustion engine. The oil level gauge is inserted into the oil return passage of the cylinder head, the oil return hole of the cylinder head gasket, and the oil return passage of the cylinder block in this order, and its lower end is immersed in the oil of the oil pan. .

Japanese Patent Laid-Open No. 2004-270510 JP 2006-189001 A Japanese Patent Laid-Open No. 9-209736

  By the way, in the internal combustion engine, the opening area of the cross-sectional areas of the oil return passages of the cylinder head and the cylinder block is set from the viewpoint of ensuring the oil return performance to the oil pan. However, when the opening area of the cross-sectional area of the oil return passages of the cylinder head and the cylinder block is increased, the following points are concerned. When assembling or disassembling the internal combustion engine, for example, foreign matter such as a head bolt washer easily enters the oil return passage of the cylinder head, and the foreign matter falls, and the oil return passage of the cylinder block, There is a possibility of intruding into an oil pan or the like. This problem is also a concern in the internal combustion engine of the type in which the oil level gauge is inserted from the cylinder head side as described above.

  The present invention has been made in view of such a problem, and in an internal combustion engine, a foreign object to an oil pan or the like with a simple configuration without changing the cross-sectional area of an oil return passage of a cylinder head and a cylinder block. It is an object of the present invention to provide a cylinder head gasket capable of suppressing the intrusion of water.

In the present invention, means for solving the above-described problems are configured as follows. That is, the present invention is a cylinder head gasket that is interposed between a cylinder head and a cylinder block of an internal combustion engine and seals between the opposing surfaces of the cylinder head and the cylinder block. An opening communicating with the formed oil return passage is formed, and the opening is partitioned into a plurality of regions, and an oil level gauge inserted from the cylinder head side can be inserted into one of the plurality of regions. It is characterized by an open shape .

According to the above configuration, since the opening is partitioned into a plurality of regions, it is difficult for foreign matters such as a head bolt washer to pass through the opening. For this reason, even when the internal combustion engine is assembled or disassembled, even if such foreign matter enters the oil return passage of the cylinder head and falls, the foreign matter is prevented from falling by the portion that defines the opening. Is possible. Thereby, it can suppress that a foreign material penetrate | invades into the oil return channel | path of the cylinder block below an opening part, the oil pan below further, etc. Therefore, with a simple configuration in which the opening of the cylinder head gasket is partitioned, entry of foreign matter into the oil pan or the like can be suppressed without changing the cross-sectional areas of the oil return passages of the cylinder head and the cylinder block.
Further, the above configuration is suitable for an internal combustion engine of a type in which an oil level gauge is inserted from the cylinder head side. That is, by using the opening of the cylinder head gasket as an insertion hole for the oil level gauge, it is not necessary to separately provide an insertion hole for the oil level gauge in the cylinder head gasket, and the cost can be reduced.

  More preferably, the sum total of the opening areas of the plurality of regions is set to at least the opening area necessary for oil return.

  According to this configuration, the oil from the cylinder head side is returned to the cylinder block side through the opening, but the opening area necessary for oil return is secured as the sum of the opening areas of the plurality of partitioned areas. The oil return performance in the internal combustion engine can be reliably ensured.

  In the present invention, it is preferable that the remaining region of the plurality of regions is configured by an opening having an opening shape through which the oil level gauge cannot be inserted. In this case, the remaining region can be constituted by a large number of openings having a small opening area.

  According to this configuration, the oil level gauge can be inserted only in the one region of the cylinder head gasket. Thereby, erroneous insertion of the oil level gauge is prevented, and an accurate oil amount can be set by the oil level gauge.

  According to the present invention, with a simple configuration of partitioning the opening of the cylinder head gasket, in an internal combustion engine, the foreign matter to the oil pan or the like can be reduced without changing the cross-sectional area of the oil return passage of the cylinder head and the cylinder block. Intrusion can be suppressed.

It is a top view which shows the cylinder head gasket which concerns on 1st Embodiment. It is sectional drawing which shows schematic structure of the internal combustion engine in which the cylinder head gasket of FIG. 1 is used, Comprising: It is a figure when an internal combustion engine is cut | disconnected by the X1-X1 line | wire of FIG. It is sectional drawing which shows schematic structure of the internal combustion engine in which the cylinder head gasket of FIG. 1 is used, Comprising: It is a figure when an internal combustion engine is cut | disconnected by the X2-X2 line | wire of FIG. It is the X3-X3 sectional view taken on the line of FIG. It is a top view which shows the cylinder head gasket which concerns on 2nd Embodiment, Comprising: It is a figure corresponding to FIG. 1 of 1st Embodiment. FIG. 6 is a cross-sectional view taken along line X4-X4 of FIG.

  EMBODIMENT OF THE INVENTION The form for implementing this invention is demonstrated referring an accompanying drawing.

-First embodiment-
FIG. 1 is a plan view showing a cylinder head gasket according to the first embodiment. FIG. 1 shows a cylinder head gasket used for an in-line four-cylinder internal combustion engine (hereinafter referred to as “engine”) for automobiles.

  Before describing the cylinder head gasket, a schematic configuration of an engine in which the cylinder head gasket is used will be described with reference to FIGS. 2 and 3 are sectional views showing a schematic configuration of an engine in which a cylinder head gasket is used. FIG. 2 is a view when the engine is cut along line X1-X1 in FIG. 1, and FIG. 3 is a view when the engine is cut along line X2-X2 in FIG.

  The engine 1 includes a cylinder block 2 having four cylinders # 1 to # 4 and a cylinder head 3 installed at the upper end of the cylinder block 2. The cylinder head 3 is fastened to the cylinder block 2 by a head bolt (not shown). A cylinder head gasket 10 is interposed between the cylinder head 3 and the cylinder block 2, and the space between the opposing surfaces of the cylinder head 3 and the cylinder block 2 is sealed.

  Four cylinders 5 are disposed in the cylinder block 2, and pistons 51 are accommodated in these cylinders 5 so as to be reciprocally movable. Each piston 51 is connected to a crankshaft via a connecting rod (not shown) so that power can be transmitted. A head cover 4 is attached to the upper surface of the cylinder head 3 via a head cover gasket 9. An oil pan 7 serving as an oil reservoir is disposed below the crankcase 6 at the lower part of the cylinder block 2.

  An intake valve 32 for opening and closing the intake port 31 and an exhaust valve 34 for opening and closing the exhaust port 33 are assembled to the cylinder head 3. The valves 32 and 34 are opened and closed by the rotation of the camshafts 35 and 36 disposed in the cam chamber formed between the cylinder head 3 and the head cover 4.

  An intake manifold (not shown) is connected to the intake port 31 formed in the cylinder head 3. The air introduced into the intake port 31 is mixed with fuel injected from an injector (not shown) to become an air-fuel mixture, and is introduced into the combustion chamber 38 when the intake valve 32 is opened.

  A spark plug 39 is disposed at the top of the combustion chamber 38. In the combustion chamber 38, the piston 51 reciprocates due to the combustion of the air-fuel mixture accompanying the ignition of the spark plug 39. The reciprocating motion of the piston 51 is transmitted to the crankshaft via the connecting rod, where it is converted into a rotational motion and taken out as an output of the engine 1. Combustion gas generated by the combustion of the air-fuel mixture passes through the exhaust port 33 as exhaust gas when the exhaust valve 34 is opened, and is then discharged to an exhaust manifold (not shown) and further exhausted to the outside through an exhaust pipe. It has become so.

  In addition, oil return passages 2 a and 3 a for returning the oil supplied to the cylinder head 3 to the oil pan 7 are formed in the cylinder block 2 and the cylinder head 3, respectively. The cylinder block 2 and the oil return passages 2a and 3a of the cylinder head 3 are communicated with each other via an oil return opening 14 of a cylinder head gasket 10 described later. In this embodiment, the oil return passages 3 a and 2 a are formed as passages extending in a substantially vertical direction from the cylinder head 3 to the cylinder block 2. The lower end of the oil return passage 2 a of the cylinder block 2 is opened so as to face the oil pan 7. The oil return passages 3a and 2a are provided, for example, between the cylinders.

  The oil supplied to the cylinder head 3 is guided to the oil return passage 3 a after finishing the lubrication of each part, flows down the oil return passages 3 a and 2 a by its own weight, and is returned to the oil pan 7. Here, the cross-sectional areas of the oil return passages 2 a and 3 a of the cylinder block 2 and the cylinder head 3 are set to areas necessary for oil return from the cylinder head 3 side to the oil pan 7. That is, it is set to an area necessary for maintaining good oil return performance to the oil pan 7 in the engine 1. Note that oil separated and removed in gas-liquid separation chambers 45 and 46, which will be described later, is also returned to the oil pan 7 by the oil return passages 3a and 2a.

  The head cover 4 is disposed so as to cover the above-described cam chamber. On the upper surface of the head cover 4, projecting portions 41 and 42 projecting upward are integrally provided at portions above the cam shafts 35 and 36 so as to extend in the axial direction of the cam shafts 35 and 36. The interiors of the protrusions 41 and 42 are gas-liquid separation chambers 45 and 46 that are partitioned by bottom plates 43 and 44. A spark plug 39 is disposed in a valley portion between the protrusions 41 and 42 on the upper surface of the head cover 4.

  A concave portion 47 that is recessed downward is formed in an intermediate portion of the protruding portion 42 in the axial direction of the camshafts 35 and 36. An insertion hole 48 into which the oil level gauge 8 is inserted is formed at the bottom of the recess 47. The opening shape of the insertion hole 48 is circular. The insertion hole 48 is arranged vertically above any one of the oil return passages 3a of the cylinder head 3 described above. That is, in this embodiment, one of the oil return passages 3a and 2a described above is also used as an oil level gauge passage into which the oil level gauge 8 is inserted. Specifically, the oil level gauge 8 is inserted into the engine 1 from the outside of the head cover 4 through the insertion hole 48, guided to the oil return passages 3 a and 2 a, and reaches the oil pan 7. . In this case, the gauge portion 81 of the oil level gauge 8 is sequentially inserted into the oil return passage 3a of the cylinder head 3, the oil return opening 14 of the cylinder head gasket 10, and the oil return passage 2a of the cylinder block 2, and its lower end. The part 81a is immersed in the oil of the oil pan 7. Further, only the gripping part 82 of the oil level gauge 8 appears outside the engine 1.

  Next, a cylinder head gasket 10 that seals between the opposed surfaces of the cylinder head 3 and the cylinder block 2 will be described with reference to FIG.

  The cylinder head gasket 10 has an outer edge shape similar to the outer edge shape on the upper surface of the cylinder block 2, and has a configuration in which, for example, two stainless steel plates are integrally laminated. The cylinder head gasket 10 has combustion chamber holes 11, 11, ..., bolt holes 12, 12, ..., water holes 13, 13, ..., oil return openings (oil return holes) 14, 14, ..., etc. A plurality of openings are formed.

  The combustion chamber holes 11, 11,... Are provided at positions corresponding to the cylinders 5, 5,. A shim is interposed between the two plate members constituting the cylinder head gasket 10 at the edge of the combustion chamber holes 11, 11,... In order to improve the sealing performance, the gasket surface pressure in the cylinder bore is increased.

  The bolt holes 12, 12,... Are provided around each combustion chamber hole 11. A head bolt that fastens the cylinder head 3 to the cylinder block 2 is inserted into each bolt hole 12. Further, the cooling water can be circulated between the cooling water passage 2b of the cylinder block 2 and the cooling water passage 3b of the cylinder head 3 through the water holes 13, 13,.

  The oil return openings 14, 14,... Are openings that communicate the oil return passages 2 a and 3 a of the cylinder block 2 and the cylinder head 3, and oil from the cylinder head 3 side is directed to the cylinder block 2 side. Provided to return. Each opening 14 is provided at a position corresponding to the oil return passages 2 a and 3 a of the cylinder block 2 and the cylinder head 3.

  One of the plurality of oil return openings 14, 14,... Is an oil level gauge passage through which the oil level gauge 8 is inserted. In this embodiment, an oil return opening 14 (hereinafter referred to as opening 14A) provided between the second cylinder # 2 and the third cylinder # 3 passes through the oil level gauge 8. It is an opening for. Hereinafter, the opening 14A through which the oil level gauge 8 is inserted will be described in detail.

  As shown in FIG. 1, the opening 14 </ b> A generally has a horizontally long shape extending along the arrangement direction of the cylinders 5 in the engine 1 (the left-right direction in FIG. 1). An annular bead portion 16 is formed around the opening portion 14A to ensure sealing performance.

  The opening 14A is divided into a plurality of (two in this embodiment) regions. Specifically, a partitioning portion 15 is formed at substantially the center in the longitudinal direction of the opening portion 14A, and the opening portion 14A is partitioned into first and second regions A1 and A2 by the partitioning portion 15. That is, the first and second regions A1 and A2 of the opening portion 14A are provided close to each other with the partition portion 15 therebetween. The opening 14A is formed, for example, by punching by pressing. In this embodiment, the first and second regions A1 and A2 have substantially the same opening shape, but as shown in FIG. 4, the oil level gauge 8 is inserted into the first region A1. It has become.

  The sum of the opening areas of the first and second regions A1 and A2 of the opening 14A is set to an area necessary for at least oil return from the cylinder head 3 side to the oil pan 7. That is, it is set to an area necessary for maintaining good oil return performance to the oil pan 7 in the engine 1. In this case, the width W1 of the partition portion 15 is narrowed so that the influence on the oil return due to the cross-sectional area of the partition portion 15 is minimized. As the width W1 of the partition portion 15, it is sufficient that a width having a strength capable of preventing the fall of a foreign substance to be described later is secured at a minimum.

  According to the cylinder head gasket 10 provided with the oil return opening 14A, the following effects can be obtained. Since the opening portion 14A is partitioned into the first and second regions A1 and A2 in the middle in the longitudinal direction by the partition portion 15, for example, foreign matter such as a head bolt washer is difficult to pass through the opening portion 14A. . For this reason, even when the engine 1 is assembled or disassembled, even if such foreign matter enters the oil return passage 3a of the cylinder head 3 and falls, the foreign matter is dropped by the partition 15 that partitions the opening 14A. Can be prevented. Thereby, it can suppress that a foreign material penetrate | invades into the oil return channel | path 2a of the cylinder block 2 below 14 A of opening parts, and the oil pan 7 etc. of the downward direction further. Therefore, the oil pan 7 or the like can be obtained without changing the cross-sectional areas of the cylinder block 2 and the oil return passages 2a and 3a of the cylinder head 3 by a simple configuration in which the opening 14A for oil return of the cylinder head gasket 10 is defined. Invasion of foreign matter into the body can be suppressed.

  Here, it is conceivable that the oil return passage 3a of the cylinder head 3 is narrowed to simply prevent the foreign matter from falling. However, from the viewpoint of ensuring oil return performance in the engine 1, it is not preferable to restrict the oil return passage 3a. In addition, the cost increases, and the waste of the cylinder head 3 increases. On the other hand, in this embodiment, the oil return opening 14A of the cylinder head gasket 10 is partitioned to prevent the entry of foreign matter into the oil pan 7 and the like while ensuring the oil return performance in the engine 1. I am doing so.

  Further, since the opening area necessary for the oil return is secured as the opening area of the opening 14A (the sum of the opening areas of the first and second regions A1 and A2), the oil return performance in the engine 1 is ensured. Can be secured.

  In addition, since the oil return opening 14 of the cylinder head gasket 10 is also used as an insertion hole for the oil level gauge 8, it is not necessary to provide an additional insertion hole for the oil level gauge 8 in the cylinder head gasket 10, thereby reducing costs. Can be planned. Further, the opening 14A partitioned into a plurality of regions can be easily formed by punching by press working or the like, and the cost can be reduced.

-Second Embodiment-
The second embodiment is an improvement of the first embodiment, and the opening shape of the oil return opening of the cylinder head gasket is different from that of the first embodiment.

  In the first embodiment, the oil return opening 14A of the cylinder head gasket 10 is partitioned into regions having substantially the same opening shape. In the second embodiment, the oil return opening of the cylinder head gasket 100 is used. The part 14B is partitioned into regions having different opening shapes.

  Specifically, as shown in FIG. 5, the opening 14 </ b> B generally has a horizontally long shape extending along the arrangement direction of the cylinders 5 in the engine 1 (the left-right direction in FIG. 5). An annular bead portion 16 is formed around the opening 14B in order to ensure sealing performance. The opening 14B is partitioned into a plurality of (two in this embodiment) regions. Specifically, a partitioning portion 15 is formed at substantially the center in the longitudinal direction of the opening 14B, and the opening 14B is partitioned into first and second regions B1 and B2 by the partitioning portion 15.

  The first area B1 of the opening 14B is an opening having an opening shape through which the oil level gauge 8 can be inserted. As shown in FIG. 6, the oil level gauge 8 is inserted into the first area B1. It is like that. On the other hand, in the second region B2 of the opening 14B, a large number of minute openings 17, 17,... Through which the oil level gauge 8 cannot be inserted are provided. That is, the second region B2 is configured by an opening having an opening shape through which the oil level gauge 8 cannot be inserted. The opening 14B having such minute openings 17, 17,... Is formed, for example, by punching by press working.

  The opening shape of the minute openings 17, 17,... Is, for example, a circle as shown in FIG. 5, and the diameter φ 2 of the minute openings 17, 17,... Is larger than the width W 2 of the gauge part 81 of the oil level gauge 8. It is getting smaller. For example, when the width W2 of the gauge portion 81 of the oil level gauge 8 is 4 mm, the diameter φ2 of the minute openings 17, 17,... May be set to 3 mm.

  And according to the cylinder head gasket 100 provided with the opening part 14B for such oil return, in addition to the effect similar to the said 1st Embodiment, the following effects are also acquired. In the first embodiment, the first and second regions A1 and A2 of the opening 14A for returning the oil of the cylinder head gasket 10 are provided close to each other with the partition portion 15 having a slight width W1, There is a possibility that the oil level gauge 8 that should be inserted into the first region A1 of the opening 14A is erroneously inserted into the second region A2. When such an erroneous insertion of the oil level gauge 8 occurs, the setting of the oil amount of the oil pan 7 by the oil level gauge 8 becomes inaccurate.

  In contrast, in this embodiment, as shown in FIG. 6, the oil level gauge 8 can be inserted only into the first region B1 of the opening 14B of the cylinder head gasket 100. Incorrect insertion is prevented, and the oil level gauge 8 can set the oil amount of the oil pan 7 accurately.

  Here, to prevent erroneous insertion of the oil level gauge 8 simply, it is conceivable to block the second region B2 of the opening 14B. However, in this case, the opening area of the opening 14B can be ensured only for the opening area of the first region B1, and it is difficult to ensure the opening area necessary for oil return. On the other hand, in this embodiment, the second area B2 of the opening 14B is not completely blocked, but is constituted by a large number of minute openings 17, 17,. While ensuring, the oil level gauge 8 is prevented from being erroneously inserted.

  In order to prevent erroneous insertion of the oil level gauge 8 simply, the opening shape of the insertion hole 48 provided in the head cover 4 is formed so as to substantially match the cross-sectional shape of the gauge portion 81 of the oil level gauge 8. It is conceivable to restrict the orientation of the gauge portion 81 of the oil level gauge 8 inserted into the hole 48. That is, by restricting the orientation of the gauge portion 81 of the oil level gauge 8 inserted into the oil level gauge passage at the insertion hole 48 at the inlet of the oil level gauge passage, erroneous insertion of the oil level gauge 8 can be prevented. Conceivable. However, in this case, there is a possibility that the oil changer suction pipe cannot be inserted into the oil level gauge passage when the oil is changed. Specifically, the cross-sectional shape of the gauge part 81 of the oil level gauge 8 is generally an elongated rectangle, whereas the cross-sectional shape of the suction pipe of the oil changer is generally circular. For this reason, when the opening shape of the insertion hole 48 of the head cover 4 is rectangular, it is difficult to insert the suction pipe of the oil changer into the insertion hole 48.

  On the other hand, in this embodiment, the erroneous insertion of the oil level gauge 8 is prevented not at the insertion hole 48 at the inlet of the oil level gauge passage but at the opening 14B of the cylinder head gasket 100 in the middle of the oil level gauge passage. I am doing so. For this reason, the opening shape of the insertion hole 48 can be made into a shape suitable for inserting the suction pipe of the oil changer.

-Other embodiments-
The embodiment of the present invention has been described above. However, the embodiment shown here is an example and can be variously modified.

  In each of the above embodiments, the case where the oil return opening of the cylinder head gasket is divided into two regions has been described. However, the oil return opening may be divided into three or more regions. For example, when the opening is divided into three regions, one region is formed as an opening having an opening shape through which an oil level gauge can be inserted, and the remaining two regions are configured by openings having an opening shape through which the oil level gauge cannot be inserted. That's fine.

  In each of the above embodiments, the case where the present invention is applied to a cylinder head gasket used in an in-line four-cylinder engine for automobiles has been described. The present invention is not limited to this, and can also be applied to cylinder head gaskets used in other numbers of cylinders and other types (for example, V-type) engines. The engine may be a gasoline engine or a diesel engine.

  INDUSTRIAL APPLICABILITY The present invention can be used for a cylinder head gasket that is interposed between a cylinder head and a cylinder block of an internal combustion engine and seals between the opposing surfaces of the cylinder head and the cylinder block. More specifically, the present invention relates to a cylinder capable of suppressing entry of foreign matter into an oil pan or the like with a simple configuration without changing the cross-sectional area of an oil return passage of a cylinder head and a cylinder block in an internal combustion engine. Useful as a head gasket.

DESCRIPTION OF SYMBOLS 1 Engine 2 Cylinder block 2a Oil return path 3 Cylinder head 3a Oil return path 7 Oil pan 8 Oil level gauge 10 Cylinder head gasket 14A Oil return opening A1 1st area | region A2 2nd area | region 15 Partition part

Claims (3)

A cylinder head gasket that is interposed between a cylinder head and a cylinder block of an internal combustion engine and seals between opposing surfaces of the cylinder head and the cylinder block,
An opening that communicates with the oil return passage formed in each of the cylinder head and the cylinder block is formed,
The opening is partitioned into a plurality of regions ,
One area of the plurality of areas has an opening shape into which an oil level gauge inserted from the cylinder head side can be inserted . The cylinder head gasket according to claim 1 ,
The remaining region of the plurality of regions is configured by an opening having an opening shape through which the oil level gauge cannot be inserted. The cylinder head gasket according to claim 1 or 2 ,
A cylinder head gasket characterized in that the sum of the opening areas of each of the plurality of regions is set to at least an opening area necessary for oil return.

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