JP2013245608A - Engine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent mixing-in of oil to cooling water and mixing-in of the cooling water to the oil, caused by abnormality of a seal member.SOLUTION: An engine 1 includes an engine body 2 for opening an outlet side passage 12 of cooling water on a front end surface 3a, a front cover 6 fixed to the engine body 2 by a bolt B1 and having a water communication passage 22 communicating with the outlet side passage 12, a water outlet member 40 fixed to the front cover, and a water seal member 27 and an oil seal member 28 interposed between the engine body 2 and the front cover 6. The front cover 6 has a fastening part 30 (abutment part) for abutting on the engine body 2 in an area between both seal members 27 and 28, and a bolt hole H1 formed in the fastening part 30 so as to penetrate through the front cover 6. The fastening part 30 is formed with a first groove part 32 for communicating with a space formed between both seal members 27 and 28 and guiding liquid (oil/cooling water) intruded into this space to the bolt hole H1.

Description

  The present invention relates to an engine, and more particularly to an engine provided with a water outlet member for cooling water at the front end of the engine.

  Conventionally, for example, an engine described in Patent Document 1 is known as an engine having a water outlet member for cooling water at the front end of the engine.

  The engine disclosed in Patent Document 1 includes a cylinder block, a cylinder head fixed to the cylinder block, a chain case (front cover) fixed over each front end of the cylinder block and the cylinder head, and the chain case. And a water outlet member fixed to the head. The chain case is formed so as to cover a transmission mechanism such as a chain for transmitting power from the crankshaft to the valve operating mechanism from the front side of the engine.

  An outlet-side passage leading to the water jacket is opened at the front end of the cylinder head, and a water passage communicating with the outlet-side passage is formed in the chain case, and the water outlet member communicates with the water passage. doing. Thus, a passage for guiding the cooling water to the water outlet member is formed so as to penetrate the accommodation space of the transmission mechanism formed between the cylinder head and the chain cover.

  A seal member is interposed between the chain case and the cylinder head, and lubricating oil (hereinafter simply referred to as oil) and cooling water supplied to the transmission mechanism are mixed with each other in the accommodation space. It is prevented.

JP 2012-2170 A

  In the above conventional engine, even if there is a situation in which oil is likely to be mixed into the cooling water due to an abnormality such as deterioration or damage of the seal member (a situation that is very likely to occur) It is difficult to detect the situation early and prevent such contamination. That is, it is possible to find an abnormality in the seal member only when oil is actually mixed into the cooling water and some troubles resulting from the mixing occur. Therefore, it has been difficult to detect an abnormality of the seal member at an early stage and take measures before the trouble occurs.

  The present invention relates to an engine having a cooling water outlet member at the front end of the engine, and can prevent the mixing of oil into the cooling water and the mixing of cooling water into the oil due to the abnormality of the sealing member. Aims to provide a new technology.

  In order to solve the above problems, an engine of the present invention includes a transmission mechanism that transmits power from a crankshaft to a valve mechanism at a front end portion in a cylinder row direction, and opens to the front end portion and serves as a water jacket. An engine body having an outlet-side passage for cooling water connected thereto, a front cover provided with a water passage that is fixed to the front end portion of the engine body so as to cover the transmission mechanism and communicated with the outlet-side passage; and A water outlet member fixed to the outer surface of the front cover and communicating with the outlet side passage of the engine body through the water passage, and the engine body so as to surround each opening of the outlet side passage and the water passage. A water seal member interposed between the front cover and an oil seal located outside the water seal member. The front cover is configured to pass through the front cover and a contact portion that contacts a front end portion of the engine body in a partial region between the water seal member and the oil seal member. A bolt hole formed in the contact portion, and the bolt is inserted into the bolt hole from the outside of the front cover and screwed to the front end portion of the engine main body to be fastened to the engine main body. Communicated with a space formed between the water seal member and the oil seal member on at least one side of the abutting portion of the front cover or the front end portion of the engine body, and in this space. A first groove for guiding the invading liquid to the bolt hole is formed.

  According to this engine, the cooling water flowing through the water jacket of the engine body is guided from the outlet side passage of the engine body through the water passage of the front cover to the water outlet member and led out to the front side of the engine. In this engine, when the water seal member or the oil seal member has an abnormality such as deterioration or damage and the oil or cooling water supplied to the transmission mechanism enters between the water seal member and the oil seal member, the liquid (Oil or cooling water; the same applies hereinafter) is guided from the space along the first groove portion to the bolt hole, and further led to the outside of the front cover through the bolt hole. As the liquid is led out of the front cover in this way, abnormalities in the water seal member and oil seal member can be detected early on from the outside of the engine before the oil mixture into the cooling water and vice versa actually occurs. It is possible to detect and perform maintenance.

  In the above configuration, the front cover has, on the outer surface thereof, a bolt seat portion that receives a head portion of a bolt inserted into the bolt hole, and the bolt seat portion is connected to the bolt hole and It is preferable that a second groove extending outward from the head of the bolt is formed.

  According to this configuration, the outflow of the liquid from the bolt hole is prevented from being hindered by the head of the bolt, and the liquid can be led out to the outside of the front cover more quickly.

  In this case, it is preferable that the second groove portion extends downward from the bolt hole.

  According to this configuration, the liquid can flow more smoothly along the second groove portion. In addition, it is possible to prevent foreign matters such as dust and mud from accumulating in the second groove portion.

  In the engine, it is preferable that the contact portion of the front cover is located below the water passage and that the first groove portion is formed to extend in the vertical direction.

  According to this configuration, the liquid that has entered between the water seal member and the oil seal member can be guided to the bolt hole through the first groove portion while being collected on the contact portion side. Therefore, the liquid that has entered the space can be more quickly guided to the bolt hole and led out of the front cover.

  The front cover is preferably formed by casting the entire front cover including the first groove portion and the second groove portion.

  According to this configuration, secondary processing for forming the first groove portion and the second groove portion on the front cover later becomes unnecessary, which contributes to improvement in productivity and cost reduction of the engine.

  As described above, according to the engine of the present invention, abnormalities such as deterioration and damage of the seal member are detected at an early stage before the mixing of oil into the cooling water or the mixing of cooling water into the oil actually occurs. It becomes possible to do. Accordingly, it is possible to prevent oil from entering the cooling water due to the abnormality of the seal member.

1 is an external perspective view showing an engine of the present invention. It is a front view of an engine (state which fixed the water outlet member). It is a front view of an engine (state which removed the water outlet member). FIG. 6 is a cross-sectional view of the engine (a cross-sectional view along the joint surface between the front cover and the engine main body; a cross-sectional view taken along the line IV-IV in FIG. 5). FIG. 5 is a cross-sectional view (cross-sectional view taken along the line VV in FIGS. 2 and 4) showing the front end portion of the engine. It is a principal part enlarged view of FIG. 4 which shows a front cover. FIG. 5 is a cross-sectional view (cross-sectional view taken along line VII-VII in FIG. 4) showing the engine front end portion. It is sectional drawing (VIII-VIII sectional view taken on the line of FIG. 4) which shows an engine front-end part. It is a principal part enlarged view of FIG. 3 which shows a bolt seat part.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 schematically shows an engine according to the invention in a perspective view. As shown in the figure, an engine 1 includes an engine body 2 having four cylinders, an oil pan (not shown) assembled to the engine body 2 from below, and a cylinder head cover assembled to the engine body 2 from above. 5 and a front cover 6 assembled to the front end of the engine body 2. The engine main body 2 is a cast product made of cast iron or aluminum alloy, and includes a cylinder block 4 that constitutes a main body portion of the cylinder, and a cylinder head 3 that is attached to the upper side of the cylinder block 4 and constitutes an upper portion of the cylinder. ing. The cylinder block 4 includes a lower block (crankcase) and an upper block fixed on the upper side thereof.

  A transmission mechanism such as a sprocket and a chain that transmits power from the crankshaft in the cylinder block 4 to the valve mechanism in the cylinder head 3 is provided at the front end of the engine body 2. The transmission mechanism is covered from the front side of the engine by the front cover 6. The space S (see FIGS. 5, 7, and 8) formed inside the front cover 6, that is, between the front surface of the engine body 2 and the front cover 6, is isolated from the outside, and in this space S, Lubricating oil flows down to the oil pan and is recovered while being supplied to the transmission mechanism. Reference numeral 8 in FIG. 1 is a crankshaft pulley attached to one end of the crankshaft, and reference numeral 9 is a VVT (Variable Valve Timing) unit incorporated in the cylinder head 3. The VVT unit 9 is not shown in the drawings other than FIG. 1 (FIGS. 2 to 4).

  A water jacket 10 (see FIG. 5) is formed in each of the cylinder head 3 and the cylinder block 4 of the engine body 2 so that cooling water can be circulated in the engine body 2. The cooling water flowing in the engine body 2 is guided to a radiator or the like outside the figure while being led out to the front side of the engine via the front cover 6 and a water outlet member 40 assembled to the front cover 6. Hereinafter, this point will be described in detail with reference to the drawings.

  2 and 3 are front views (main parts) of the engine 1, and FIG. 3 shows a state where the water outlet member 40 is removed. 4 is a cross-sectional view of the engine 1 and is a cross-sectional view (a cross-sectional view taken along the line IV-IV in FIG. 5) along the joint surface between the engine body 2 and the front cover 6. FIG. 5 is a cross-sectional view taken along line VV shown in FIGS. 2 and 4. FIG. 6 is an enlarged view of a main part of FIG. 4 showing a post-joining part 20 of the front cover 6.

  As shown in FIG. 5, a cooling water outlet side passage 12 communicating with the water jacket 10 is opened in the front end surface 3 a of the cylinder head 3 of the engine body 2. On the other hand, at the position facing the outlet side passage 12 on the rear side surface of the front cover 6, it protrudes toward the cylinder head 3 and comes into contact with the front end surface 3 a and is thicker than other parts of the front cover 6. The joint part 20 formed in is provided. The joint portion 20 is formed with a water passage 22 having a circular cross section that penetrates the front cover 6 in the front-rear direction and communicates with the outlet-side passage 12, whereby the engine 1 is connected from the cylinder head 3 to the front cover. The cooling water can be led out to the front side of the engine via 6.

  As shown in FIGS. 4 and 6, the end surface of the joint portion 20 on the cylinder head side faces from the position of the water passage 22 to the side (right side in the figure) when viewed from the rear (cylinder head 3 side). It has a slightly pointed saddle shape. Of the end surface of the joint portion 20, a portion other than the outer peripheral edge portion 20 a and the inner peripheral edge portion 20 b along the water passage 22 (except for the fastening portion 30 described later) is recessed (referred to as a recess 24). As shown in FIG. 5, the inner bottom portion of the recess 24 includes an inner groove portion 25 a that is continuous in the circumferential direction so as to surround the water passage 22 along the inner wall portion, that is, the wall portion on the water passage 22 side. An outer groove portion 25b that is continuous in the circumferential direction is formed along the outer wall portion.

  Of these grooves 25a and 25b, for example, an endless water seal member 27 having a substantially rectangular cross section is fitted into the inner groove 25a, and an endless oil seal member 28 having a substantially rectangular cross section is similarly inserted into the outer groove 25b. It is inserted. As described above, the water seal member 27 and the oil seal member 28 are provided inside and outside the end surface of the joint portion 20 so as to surround the water passage 22, so that the space between the joint portion 20 (front cover 6) and the cylinder head 3 is provided. Is sealed, and the outlet side passage 12 and the water passage 22 of the cylinder head 3 are connected in a liquid-tight state.

  Of the concave portion 24 of the joint portion 20, a partial region between the inner groove portion 25 a (water seal member 27) and the outer groove portion 25 b (oil seal member 28), specifically, the hook-shaped portion is formed. The sharpened portion of the joint portion 20 protrudes from the inner bottom portion of the concave portion 24 toward the cylinder head 3 side, and has a fastening portion 30 (abutting contact according to the present invention) having an end surface that is flush with the end surfaces of the peripheral edge portions 20a and 20b. Corresponding to the portion).

  The fastening portion 30 is formed with a bolt hole H1 penetrating the front cover 6 in the front-rear direction, and a bolt B1 for fastening and fixing the front cover 6 to the cylinder head 3 is inserted. Bolt holes H1 penetrating the front cover 6 in the front-rear direction are formed in the front cover 6 at a plurality of positions along the peripheral edge thereof, at a plurality of positions near the water passage 22 and at a plurality of other positions, respectively. 2, 3, and 7, bolts B <b> 1 are inserted into the respective bolt holes H <b> 1 from the front side of the front cover 6, and these bolts B <b> 1 are screwed into screw holes H <b> 2 formed in the cylinder head 3. In this case, the front cover 6 is fastened and fixed to the cylinder head 3 by being inserted. That is, one of the bolt holes H <b> 1 for fastening the front cover is formed in the fastening portion 30, and therefore the end surface of the fastening portion 30 is a joint surface between the front cover 6 and the cylinder head 3. In this example, in order to ensure the sealing performance of the sealing members 27 and 28, the front cover 6 is fastened to the cylinder head 3 by bolts B1 at three positions surrounding the water passage 22 as shown in FIG. One of the fastening locations is the fastening portion 30.

  A first groove portion 32 as shown in FIGS. 4, 6, and 8 is formed on the end surface of the fastening portion 30 (joint surface with the cylinder head 3). The first groove portion 32 guides the liquid to the bolt hole H1 formed in the fastening portion 30 when oil or cooling water (hereinafter, appropriately referred to as liquid) enters between the seal members 27 and 28. Is to do. That is, in the state where the front cover 6 is fastened to the cylinder head 3, as shown in FIGS. 5 and 6, around the water passage 22, the front end surface 3 a of the cylinder head 3, the inner bottom portion of the recess 24, both seals A space defined by the members 27 and 28 and the fastening portion 30 is formed. The first groove portion 32 is formed in the fastening portion 30 so that this space communicates with the bolt hole H1. Therefore, when cooling water leaks from the water passage 22 into the space due to an abnormality such as deterioration or damage of the water seal member 27, the cooling water is introduced into the bolt hole H1 through the first groove portion 32, while the oil When oil enters the space due to an abnormality such as deterioration or damage of the seal member 28, the oil is introduced into the bolt hole H <b> 1 through the first groove portion 32.

  On the other hand, as shown in FIGS. 7 and 9, a bolt seat portion 34 that receives the head of the bolt B <b> 1 inserted into the bolt hole H <b> 1 of the fastening portion 30 is formed on the front surface portion of the front cover 6. As shown in the figure, the bolt seat 34 is formed of a circular recess recessed toward the cylinder head 3, and the inner bottom surface thereof is connected to the bolt hole H1 and extends downward from the bolt hole H1. The 2nd groove part 36 which reaches the position outside the head of B1 is formed. The second groove portion 36 allows the liquid led out to the front side of the front cover 6 through the bolt hole H1 to smoothly flow down from the bolt hole H1. That is, the formation of the second groove portion 36 prevents the liquid flow from the bolt hole H1 from being hindered by the head of the bolt B1. The front cover 6 is a cast product as described above, and the first groove portion 32 and the second groove portion 36 are formed when the front cover 6 is cast.

  The water outlet member 40 is attached to the front surface of the front cover 6 at a position corresponding to the water passage 22. As shown in FIG. 2, the water outlet member 40 includes a flange portion 42, a main pipe portion 43 extending from the flange portion 42, branch pipe portions 44 and 45 branched from the main pipe portion 43, and a base end portion of the main pipe portion 43. The flange portion 42 is fastened and fixed to the front surface of the front cover 6 by bolts B2 so that the front cover 6 is detachably assembled. Specifically, as shown in FIGS. 3 and 5, a water outlet member 40 having a plurality of screw holes H <b> 5 having a shape corresponding to the flange portion 42 and extending in the front-rear direction on the front surface of the front cover 6. The mounting seat 48 is formed. On the other hand, a bolt hole H4 penetrating in the front-rear direction is formed in the flange portion 42 of the water outlet member 40. And the flange part 42 of the said water outlet member 40 is piled up on the mounting seat part 48 via the gasket etc. which are not shown in figure, The volt | bolt B2 is inserted in each bolt hole H4 from the front side of the front cover 6, and these volt | bolts B2 are attached. The water outlet member 40 is fastened and fixed to the front cover 6 by being screwed into and inserted into the screw hole H5 of the front cover 6. In this fixed state, the flange portion 42 of the water outlet member 40 communicates with the water passage 22 of the front cover 6 as shown in FIG.

  Next, the effect of the engine 1 mentioned above is demonstrated.

  In the engine 1 described above, the cooling water flowing in the engine body 2 is led out from the outlet side passage 12 of the cylinder head 3 to the front side of the engine 1 through the water passage 22 and the water outlet member 40 of the front cover 6. Guided by an external radiator. In this configuration, the outlet-side passage 12 of the cylinder head 3 and the water passage 22 of the front cover 6 are connected in a liquid-tight state by the water seal member 27 and the oil seal member 28. Are not mixed with each other, but if the water-tight state is destroyed due to the deterioration or damage of the water seal member 27 or the oil seal member 28, the oil and the cooling water It is conceivable to be mixed in. However, according to the engine 1, it is possible to prevent such inconvenience from occurring.

  That is, when the cooling water in the water passage 22 leaks between the sealing members 27 and 28 due to the abnormality of the water seal member 27, the cooling water is introduced into the bolt hole H1 through the first groove portion 32. It flows down to the front side of the front cover 6 through the bolt hole H1. Since the cooling water is generally colored for the early detection of water leakage, when the cooling water flows down along the front side of the front cover 6 as described above, the traces of the cooling water are removed. The abnormality of the water seal member 27 can be detected at an early stage from the outside of the engine 1. The same applies when oil enters between the seal members 27 and 28 due to an abnormality in the oil seal member 28. Therefore, when an abnormality occurs in either the water seal member 27 or the oil seal member 28, it becomes possible to detect the abnormality of the seal members 27 and 28 at that stage, and oil is mixed into the cooling water. It is possible to perform appropriate maintenance before the cooling water actually enters the oil or oil. Accordingly, it is possible to prevent the mixture of oil into the cooling water and the mixture of cooling water into the oil due to the abnormality of the seal members 27 and 28.

  In particular, in this example, a fastening portion 30 is formed in a partial region between the water seal member 27 and the oil seal member 28, and the fastening portion 30 is in contact with the cylinder head 3 (front end surface 3a). The fastening portion 30 is joined to the cylinder head 3 by a bolt B1. According to such a configuration, a sufficient contact surface pressure between the front cover 6 (fastening portion 30) and the cylinder head 3 can be secured, while a liquid (oil) is interposed between the water seal member 27 and the oil seal member 28. A moderate space capable of storing (cooling water) is formed well. Therefore, the liquid that enters between the water seal member 27 and the oil seal member 28 flows smoothly into the bolt hole H1 through the first groove portion 32 while accumulating in the space, and as a result, the liquid is quickly discharged. It can be led out of the front cover 6.

  Furthermore, the second groove portion 36 connected to the bolt hole H1 and extending downward is formed in the bolt seat portion 34 that receives the head portion of the bolt B1, so that the liquid flows from the bolt hole H1 by the head portion of the bolt B1. Inhibition is prevented. Therefore, the liquid can flow smoothly from the bolt hole H1 along the front surface of the front cover 6 to leave the trace. Moreover, since the 2nd groove part 36 is extended downward, it can suppress that a garbage, mud, etc. accumulate in the said 2nd groove part 36, and this point also contributes to the smooth flow of a liquid.

  Further, according to the engine 1, the bolt hole H1 into which the bolt B1 is inserted is used to fasten and fix the front cover 6 to the cylinder head 3, and the liquid is transferred to the front surface of the front cover 6 through the bolt hole H1. Since it is the structure which guide | induces, there also exists an advantage that the above effects can be enjoyed very simply and at low cost. Further, since the first groove portion 32 and the second groove portion 36 are formed at the same time when the front cover 6 is cast, productivity is higher than when the grooves 32 and 36 are secondarily processed on the front cover later. There is also an advantage that it contributes to cost reduction.

  In addition, the engine 1 demonstrated above is an illustration of preferable embodiment of the engine concerning this invention, The specific structure can be suitably changed in the range which does not deviate from the summary of this invention.

  For example, in the above embodiment, the first groove portion 32 that guides the liquid that has entered the space between the seal members 27 and 28 to the bolt hole H1 is formed on the front cover 6 side (fastening portion 30) (FIG. 8). The first groove portion 32 may be formed on the cylinder head 3 side (front end surface 3a). Moreover, the 1st groove part 32 may be formed in both the front cover 6 (fastening part 30) and the cylinder head 3 (front-end surface 3a). In this case, the front cover 6 side and the cylinder head 3 side may each be provided with a first groove portion 32 that guides the liquid to the bolt hole H1 through different routes. The first groove portion 32 may be formed in cooperation with the groove portion on the cylinder head 3 side.

  Moreover, although the front cover 6 of the said embodiment is formed so that the fastening part 30 may be located in the side of the water flow path 22, as shown with a dashed-two dotted line in FIG. The fastening part 30 may be located in the first groove part 32 so that the first groove part 32 extends in the vertical direction. According to this configuration, it is possible to smoothly guide the liquid that has entered between the seal members 27 and 28 to the bolt hole H1 while collecting the liquid in the fastening portion 30.

DESCRIPTION OF SYMBOLS 1 Engine 2 Engine main body 3 Cylinder head 4 Cylinder block 12 Outlet side channel | path 20 Joint part 22 Water flow path 27 Water seal member 28 Oil seal member 30 Fastening part (contact part)
32 1st groove part 36 2nd groove part 40 Water outlet member B1, B2 Bolt H1, H4 Bolt hole H2, H5 Screw hole

Claims (5)

An engine,
An engine body having a transmission mechanism for transmitting power from the crankshaft to the valve mechanism at the front end in the cylinder row direction, and having an outlet side passage for cooling water that opens to the front end and connects to the water jacket;
A front cover that is fixed to the front end of the engine body by a bolt so as to cover the transmission mechanism, and includes a water passage communicating with the outlet-side passage;
A water outlet member fixed to the outer surface of the front cover and connected to the outlet side passage of the engine body through the water passage;
A water seal member interposed between the engine body and the front cover so as to surround each opening of the outlet side passage and the water passage, and an oil seal member located outside the water seal member; With
The front cover is formed in the contact portion that contacts the front end portion of the engine body in a partial region between the water seal member and the oil seal member, and the contact portion so as to penetrate the front cover. A bolt hole, and the bolt is inserted into the bolt hole from the outside of the front cover and screwed to the front end of the engine body, and is fastened to the engine body.
At least one side of the abutting portion of the front cover or the front end portion of the engine body communicates with the space formed between the water seal member and the oil seal member, and the liquid that has entered the space An engine characterized in that a first groove for guiding the bolt hole is formed. The engine according to claim 1,
The front cover has a bolt seat on its outer surface for receiving a head of a bolt inserted into the bolt hole, and the bolt seat is connected to the bolt hole and the head of the bolt. An engine characterized in that a second groove portion extending outward from the portion is formed. The engine according to claim 2,
The engine, wherein the second groove portion extends downward from the bolt hole. The engine according to any one of claims 1 to 3,
The engine is characterized in that the abutting portion of the front cover is located below the water passage, and the first groove portion is formed to extend in the vertical direction. The engine according to claim 2 or 3,
The engine, wherein the front cover is formed by casting the entire front cover including the first groove portion and the second groove portion.

Images