Pipe holding structure in an internal combustion engine

Abstract

To disclose a structure capable of performing connection without straining and improving sealability, in a pipe one end of which is inserted into a connection port and in which a bracket is fixed to a bolt.SOLUTION: A sealing material (O-ring 18) is mounted to one end part 15a of a cooling water return pipe 15. A hose 16 is connected to the other end part 15b of the cooling water return pipe 15. A first bracket 24 and a second bracket 25 facing in opposite directions are fixed to the cooling water return pipe 15, and the second bracket 25 is fixed to a cylinder block 1 with a bolt 35. When the cooling water return pipe 15 is inserted into a connection port 13, a cut groove 26 provided in the first bracket 24 is fitted into a receiving member (stud bolt 27) protruding from a cylinder head 2. Consequently, the posture of the cooling water return pipe 15 is maintained. The stud bolt 27 also functions as a rotation stopper when fixing another member 28 with a bolt 29.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a holding structure for a pipe used in association with an internal combustion engine for vehicles or the like.

Background Art

[0002] An engine is attached with a pipe through which a fluid such as cooling water flows, and the pipe may be fixed to a component of the engine. As an example, in Patent Document 1, as a structure for fixing a pipe (tube) through which cooling water for an oil cooler flows to a transmission case, a fixing bracket is composed of a first bracket fixed to the pipe and a second bracket bolted to the transmission case, and the tip portions of both brackets are overlapped with each other, and the overlapping portion of both brackets is engaged by fitting an engaging claw and an engaging hole (engaging hole).

[0003] In Patent Document 1, after both ends of the pipe are fixed (connected), the first bracket is bolted to the transmission case. However, in the state before fixing with the bolt, the relative posture of the first bracket and the second bracket can be changed. Therefore, even when the axis of the bolt fixing one end of the pipe and the axis of the bolt fixing the first bracket are not parallel, the fixing operation of the first bracket can be easily performed (when fixing one end of the pipe with a bolt, the first bracket can be separated from the transmission case). In this case, since the first bracket is prevented from rotating with respect to the second bracket by fitting the engaging claw and the engaging hole, the fastening operation of the first bracket with the bolt can also be easily performed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Now, the coolant cooled by the radiator is returned to the water pump via a return line. In this case, the return line is typically composed of a metal pipe with one end (downstream end) connected to the water pump's connection port and a flexible hose connected to the other end (upstream end) of the pipe.

[0006] Furthermore, one end of the pipe is fitted with an O-ring so that it can be connected simply by inserting it into the connection port, while a first bracket and a second bracket are fixed to the middle of the pipe. The second bracket is bolted to the engine body, and the first bracket is fitted into a receiving part provided on the engine body to maintain its position. With this configuration, the pipe's position is maintained by the two brackets, ensuring ease of connection of the pipe to the water pump while also allowing for a secure connection of the hose.

[0007] In this case, it is possible to use stud bolts as receiving members. When using stud bolts, for example, when fixing the main body case of the air cleaner to the engine body with bolts, the bracket portion provided on the main body case can be fitted onto the stud bolts, thereby using the stud bolts as an anti-rotation device and making it easier to fasten the main body case with bolts.

[0008] Furthermore, regarding the fitting relationship between the first bracket and the stud bolt, it is conceivable to drill a round or elongated hole in the first bracket and then fit the first bracket onto the stud bolt. However, in this case, if the axis of one end of the pipe is perfectly parallel to the connection port, the first bracket will collide with the stud bolt when inserting the pipe into the connection port.

[0009] Therefore, one end of the pipe is inserted into the connection port with its axis slightly tilted relative to the axis of the connection port. However, this can cause twisting between the pipe and the connection port, making insertion difficult, and may also cause the O-ring to curl or break, resulting in a poor seal.

[0010] The present invention was made to improve this current situation. [Means for solving the problem]

[0011] The present invention relates to a pipe holding structure in an internal combustion engine. " Long in a certain direction A pipe and The aforementioned pipe By moving the pipe in the longitudinal direction, A connection port into which one end is fitted, A receiving member positioned near the aforementioned pipe, Yes, An internal combustion engine in which a bracket is provided on the pipe for connecting to the receiving member to maintain its position, and a fitting portion is formed on the bracket that engages with the receiving member when the pipe is moved toward the connection port. In this basic configuration, "The receiving member is a stud bolt or other circular projection oriented perpendicular to the longitudinal direction of the pipe." The fitting portion of the bracket is a cut-out groove that opens in the direction of the circular projection. This is the structure.

[0012] The present invention can be implemented in various ways. As an example, claim 2 states: " The pipe is positioned to extend long in the direction of the crank axis, and the bracket having the cut-out groove and the other bracket are provided on the pipe so as to protrude on opposite sides of the pipe. The bracket having the cut-out groove has an inclined portion that slopes away from the pipe as it approaches the connection port, and the cut-out groove is formed in the inclined portion. The aforementioned brackets are bolted to the engine body. " This is the structure. [Effects of the Invention]

[0013] If we call the bracket with the cut-out groove the first bracket, and the other brackets the second bracket,In the invention of the present application, when the pipe is fitted into the connection port, the holding portion of the first bracket is fitted into the receiving member and the posture is held, so that one end portion of the pipe can be fitted in a posture concentric with one end portion of the connection port. Therefore, when fitting one end portion of the pipe into the connection port, no kinking occurs, and the connection work of the pipe can be accurately performed with a light force, and problems such as damage or turning back of a gasket such as an O-ring do not occur, and the desired sealing property can be maintained.

[0014] In claim 2, since the second bracket is fixed with bolts, the mounting strength of the pipe is high. However, since the circular protrusion, which is the receiving member, serves as a rotation stopper (positioning) for the pipe, it is not necessary to manually hold the posture of the pipe one by one during the fixing work of the bolts, and the fastening work can be performed quickly. In the engine body Also, when a circular receiving member and an engagement portion of the split groove type are adopted as described above, since the receiving member has no directionality when viewed from the axial direction, the clearance between the split groove and the receiving member can be made as small as possible, and the mounting accuracy of the pipe can be improved. There is also an advantage that a circular protrusion such as a stud bolt can be used in combination for posture holding (rotation prevention when fastening with bolts) of other members (for example, an air cleaner). As the circular protrusion, for example, a press-fit pin can also be used, but when a stud bolt is used, there is an advantage that the first bracket and other members can be fixed with nuts.

[0015] Also, The present invention When a circular receiving member and an engagement portion of the split groove type are adopted as described above, since the receiving member has no directionality when viewed from the axial direction, the clearance between the split groove and the receiving member can be made as small as possible, and the mounting accuracy of the pipe can be improved. There is also an advantage that a circular protrusion such as a stud bolt can be used in combination for posture holding (rotation prevention when fastening with bolts) of other members (for example, an air cleaner). As the circular protrusion, for example, a press-fit pin can also be used, but when a stud bolt is used, there is an advantage that the first bracket and other members can be fixed with nuts.

[0016] Further, in claim 2, when the bolt insertion hole of the second bracket is set to a circular shape slightly larger than the outer diameter of the bolt, if the pipe tries to move in the removal direction even slightly, its movement is blocked by the bolt. Therefore, while the pipe can be easily fitted, it has an excellent function of preventing removal.

Brief Description of the Drawings

[0017] [Figure 1] It is a perspective view of the pipe viewed from the side direction of the engine. [Figure 2]In the diagram of the pipe itself, (A) is a plan view, (B) is a side view, and (C) is a cross-sectional view of (B) and (C) from a cross-sectional perspective. [Figure 3] This figure shows another embodiment. [Modes for carrying out the invention]

[0018] Next, embodiments of the present invention will be described based on the drawings. In the following, the terms front / rear and left / right will be used to specify directions, where the front / rear direction is the direction of the crank axis, and the left / right direction is the direction perpendicular to the crank axis and cylinder axis. The front and rear are defined as the side where the timing chain is located and the rear as the side where the transmission case is located.

[0019] (1) Engine Overview This embodiment is embodied in a pipe connection structure attached to an automobile engine (internal combustion engine). First, the embodiment shown in Figures 1 and 2 will be described. As shown in Figure 1, the engine is As the main body of the organization, C Lin The engine has a double block 1 and a cylinder head 2 fixed to its upper surface, with a head cover (not shown) fixed to the upper surface of the cylinder head 2. The cylinder head 2 has one exhaust outlet hole 3. Therefore, Figure 1 is a view from the exhaust side.

[0020] Around the exhaust outlet hole 3, tapped holes 4 are provided into which stud bolts or hexagonal bolts are screwed. The exhaust turbocharger or catalytic converter case is secured using these tapped holes 4 (if the exhaust turbocharger is secured, the catalytic converter case is secured to the exhaust turbocharger's outlet flange).

[0021] A front cover 5 is fixed to the front of the cylinder block 1 and cylinder head 2 with a group of bolts. The timing chain described above is located in the space enclosed by the front cover 5, the cylinder block 1, and the cylinder head 2. In Figure 1, the boundary between the cylinder block 1 and the cylinder head 2 is shown by a thick line 6, and the boundary between the cylinder block 1 and the cylinder head 2 and the front cover 5 is shown by a thick line 7. A ring gear 8, which engages with the gears of the starter motor, is located on the rear of the cylinder block 1.

[0022] The rear of the cylinder head 2 is a water distribution section 9, and the water distribution section 9 is provided with a radiator supply port 10 and other coolant ports 11. A thermostatic valve (not shown) is located inside the radiator supply port 10.

[0023] A pump housing 12, which constitutes the water pump, is formed on the upper part of the front cover 5, where it is located above the sinker block 1, so as to protrude to the outside of the sinker block 1. A pump cover 14, which has a connection port 13 that protrudes backward, is formed integrally with the front cover 5 on the rear surface of the pump housing 12. The pump cover 14 may be fixed with a group of bolts (not shown). The water pump is driven by an auxiliary drive belt wrapped around the crank pulley or by an electric motor.

[0024] A metal coolant return pipe 15 is connected to the water pump connection port 13. The coolant return pipe 15 is generally oriented in a longitudinal position, with one end (downstream end) 15a connected to the connection port 13 by insertion, and a flexible radiator return hose 16 fitted onto the other end (upstream end) 15b from the outside.

[0025] In this case, the coolant return pipe 15 will have one end 15a lower and the other end 15b higher. The structure is formed in a stepped manner when viewed from the side. Furthermore, as shown in Figure 2(A), the cooling water return pipe 15 is curved in plan view as well, with slightly more than half of it, closer to the sinker block 1, near the other end 15b, and a portion of the side of one end 15a moving away from the sinker block 1. Therefore, the cooling water return pipe 15 is bent in a crank shape in both plan view and side view.

[0026] Accordingly, the coolant return pipe 15 has an outlet-side horizontal section 15c that is horizontal and away from the sinker block 1, an inlet-side horizontal section 15d that is horizontal and close to the sinker block 1, and an inclined section 15e that connects the two. Two annular protrusions 17 are formed at one end 15a of the coolant return pipe 15, and an O-ring 18, as an example of a sealing material, is fitted between the two annular protrusions 17. On the other hand, a pair of front and rear annular protrusions 19 are formed at the other end of the coolant return pipe 15, and the radiator return hose 16, which is fitted to the other end from the outside, is tied and held in place by a hose handle located between the front and rear annular protrusions 19.

[0027] A heater return port 20, formed in an inverted L shape from a metal pipe, is connected to the horizontal inlet portion 15d of the coolant return pipe 15. A heater return hose 21 (see Figure 2(B)) through which coolant discharged from the heater for interior heating flows is fitted into the heater return port 20. A pair of annular protrusions 22 are also formed at the tip of the heater return port 20. The coolant return pipe 15 also functions as a bypass pipe that returns coolant that is not sent to the radiator when the engine is cold to the water pump.

[0028] (2) Fixing structure for the cooling water return pipe A first bracket 24, made of metal plate and protruding upward, is fixed to the horizontal inlet portion 15d of the cooling water return pipe 15 by welding or brazing, and a second bracket 25, made of metal plate and protruding downward, is fixed to the horizontal outlet portion 15c of the cooling water return pipe 15 by welding or brazing. The first bracket 24 and the second bracket 25 are positioned in opposite directions. The first bracket corresponds to the bracket described in claim 1, and the second bracket corresponds to the other bracket described in claim 2.

[0029] As shown in Figure 2(C), the first bracket 24 is curved so that its lower end overlaps the inlet-side horizontal portion 15d, and this portion is brazed or welded to the inlet-side horizontal portion 15d of the coolant return pipe 15. Furthermore, the first bracket 24 rises upward in close proximity to the exhaust side of the cylinder head 2, and its upper half has a forward-facing inclined portion 24a that rises towards the front.

[0030] As shown in Figure 2, a forward-opening cut-out groove 26 is formed at the front end of the forward-sloping portion 24a as an example of an engaging portion. The opening edge of the cut-out groove 26 is a tapered portion 26a that widens vertically. A stud bolt 27 is provided protruding from the intake side of the cylinder head 2, which is an example of a receiving member as described in the claim, into which the cut-out groove 26 of the first bracket 24 fits. The stud bolt 27 is oriented perpendicular to the longitudinal axis of the coolant return pipe 15.

[0031] As shown in Figure 1, the main body case (dirty chamber) 28 of the air cleaner is located above the rear of the cylinder head 2. Part of the main body case 28 is fixed to the cylinder head 2 by hexagonal bolts 29, and a bracket portion 31 having a positioning hole 30 that fits into a stud bolt 27 is integrally formed in the main body case 28. Alternatively, a separate structure in which the main body case 28 and the bracket portion 31 are connected via a grommet can also be adopted.

[0032] The main body case 28 of the air cleaner is installed after the coolant return pipe 15 is fixed. Therefore, with the cut-out groove 26 of the first bracket 24 fitted onto the stud bolt 27, the bracket part 31 is fitted onto the stud bolt 27, and in that state the hex bolt 29 is screwed in, but since the main body case 28 is prevented from rotating by the stud bolt 27, the hex bolt 29 is screwed in without having to manually hold the position of the main body case 28. Cut.

[0033] As shown in Figure 2(B), the stud bolt 27 is screwed into an upper boss portion 32 that protrudes outward from the cylinder head 2, and the first bracket 24 overlaps the upper boss portion 32. In addition, the tapped hole into which the hexagonal bolt 29 is screwed is formed in a boss portion (not shown) provided on the cylinder head 2. As shown in Figures 2(B) and 2(C), a reinforcing rib 24b that protrudes outward is provided on the inner corner of the first bracket 24.

[0034] Furthermore, the first bracket 24 and the heater return port 20 cross each other in a side view when the heater return port 20 is positioned on the outside. Also, the first bracket 24 and the heater return port 20 are located above the catalyst case. Therefore, the first bracket 24 and the heater return port 20 do not obstruct the catalyst case.

[0035] As previously described, the second bracket 25 is fixed to the inclined portion 15e of the cooling water return pipe 15 by welding or brazing, and in a side view, it is formed to curve towards the rear as it goes downwards. The upper end of the second bracket 25 is also curved so as to partially overlap the inclined portion 15e, and the lower end of the second bracket 25 is fixed to the lower boss portion 34 provided on the sinker block 1 with a bolt (hex bolt) 35 (see Figure 1).

[0036] The bolt insertion holes 36 of the second bracket 25 are circular. Reinforcing ribs 25a are also provided on both longitudinal edges of the second bracket 25. Nuts 37 can also be screwed onto the stud bolts 27.

[0037] In the above configuration, the cooling water return pipe 15 Move it forward When one end 15a is inserted into the water pump connection port 13, the insertion motion causes the cut-out groove 26 of the first bracket 24 to engage with the stud bolt 27. In other words, when one end 15a of the coolant return pipe 15 is inserted concentrically with the connection port 13, the cut-out groove 26 of the first bracket 24 engages with the stud bolt 27, and the position of the coolant return pipe 15 is maintained.

[0038] In this case, since the tip of the first bracket 24 has a tapered section that widens towards the end, the movement of the first bracket 24 is guided so that the cut-out groove 26 fits onto the stud bolt 27, and the coolant return pipe 15 is held in a position concentric with the connection port 13, with one end 15a of the coolant return pipe 15. Therefore, the coolant return pipe 15 can be accurately connected to the connection port 13. Thus, the work can be performed easily with little force, and there is no damage or peeling of the O-ring 18, and high sealing performance can be maintained.

[0039] Furthermore, since the bolt insertion hole 36 of the second bracket 25 is circular, even if an external force acts on the coolant return pipe 15 in a direction that would cause it to pull out from the connection port 13, the coolant return pipe 15 is prevented from moving backward by the bolt 35. Therefore, a high level of anti-dislodgement function can be maintained while maintaining ease of connection work.

[0040] Reference example This is shown in Figure 3. In the example shown in Figure 3(A), an L-shaped receiving member 38 is fixed to a component such as the cylinder head 2, and an engagement hole 39 is provided in the receiving member 38, while a horizontal engagement rod 40 that fits into the engagement hole 39 is provided in the cooling water return pipe 15.

[0041] Furthermore, in the example shown in Figure 3(B), a U-shaped receiving member 38 is provided on components such as the cylinder head 2, while an upward-facing engaging rod 40 that enters the inside of the receiving member 38 is provided on the coolant return pipe 15. In this example, the engaging rod 40 can be used to prevent other components from rotating.

[0042] Book In the proposed invention, various combinations of the receiving member and the engaging part can be used. Furthermore, the pipe to which it can be applied is not limited to coolant return pipes, but can also be applied to air ducts, etc. Moreover, it can be broadly applied to pipes arranged around the engine. In the embodiment, the pipe is inserted inside the connection port, but it can also be applied to a structure in which the pipe is fitted into the connection port from the outside. As the circular projection, the head of a bolt with a socket hole can also be used. [Industrial applicability]

[0043] The present invention can be embodied in a fixing structure for engine-related pipes. Therefore, it can be used industrially. [Explanation of Symbols]

[0044] 1 C Lin Dublock 2 Cylinder heads 3 Exhaust outlet holes 4 tapped holes 5 Front cover 6. Boundary between cylinder block and cylinder head 7 C Lin boundary between the double block and cylinder head and the front cover 8 Ring Gear 9 Water distribution department 10 Radiator feed ports 11 Cooling water ports 12. Pump housing that makes up the water pump 13 connection ports 14 Pump cover 15 Coolant return pipe 16. Radiator return hose 17 Annular projection 18 O-rings 19 Annular projection 20 Heater return ports 21 Heater return hose 23 Annular projection 24 First bracket (Bracket according to claim 1) 24a Slope 25 Second bracket (Other brackets) 26 Cutting groove 27 Stud bolts 28 Air cleaner main case 29 Hex bolts 30 positioning holes 31 Bracket section 32 Upper Boss Section 34 Lower Boss Section 35 Bolts for securing the second bracket 36 Bolt insertion holes of the second bracket

Claims

1. A pipe that is long in a certain direction, By moving the aforementioned pipe in the longitudinal direction, a connection port into which one end of the pipe is fitted is located, It has a receiving member positioned near the pipe, In an internal combustion engine, the pipe is provided with a bracket for connecting to the receiving member to maintain its orientation, and the bracket has a fitting portion formed thereon that engages with the receiving member when the pipe is moved toward the connection port, The receiving member is a stud bolt or other circular projection oriented perpendicular to the longitudinal direction of the pipe. The fitting portion of the bracket is a cut-out groove that opens in the direction of the circular projection. A pipe holding structure in an internal combustion engine.

2. The pipe is positioned to extend long in the direction of the crank axis, and the bracket having the cut-out groove and the other bracket are provided on the pipe so as to protrude on opposite sides of the pipe, The bracket having the cut-out groove has an inclined portion that slopes away from the pipe as it approaches the connection port, and the cut-out groove is formed in the inclined portion. The other brackets mentioned above are bolted to the engine body. A pipe holding structure for an internal combustion engine as described in claim 1.

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