JP6007151B2 - Mounting structure of oil injection device for cooling piston in internal combustion engine - Google Patents

Description

  The present invention relates to a structure for mounting an oil injection device for cooling a piston in an internal combustion engine.

  In order to cool the inner surface of the piston top of the internal combustion engine, there has been a mounting structure in which an oil injection device for piston cooling that injects oil toward the inner surface of the piston top is attached to the inner surface of the crankcase or cylinder block (Patent Document 1). reference).

JP 2011-208581 A

  The oil injection device is integrally formed with an injection device main body having an oil passage that can be detachably connected to an oil passage provided in a crankcase or a cylinder block, and from the injection device main body toward the piston in the cylinder bore. A nozzle portion that extends and has an oil injection port; and a flange portion that is formed integrally with the injection device main body portion and has a contact surface that can contact the inner surface of the crankcase or the cylinder block. The extending direction of the nozzle portion is parallel to the contact surface that is in contact with the inner surface of the case. The injection device main body and the flange are installed on a continuous surface in the crankcase or the cylinder block, that is, on the same plane.

  For this reason, when the oil injection device is attached to the inner surface of the crankcase, when the bolt that passes through the flange portion and is screwed to the crankcase or the cylinder block is tightened, the body portion is also rotated along with the rotation of the bolt. As a result, a force in the rotational direction is applied to the main body, and the main body is likely to be displaced or tilted, resulting in uneven sealing between the crankcase and the main body, or the position of the main body. There is a possibility that the oil injection accuracy due to the deviation is lowered.

  An object of the present invention is to provide an oil injection device for cooling a piston capable of reliably supplying oil to an inner surface of a piston of an internal combustion engine.

  According to the first aspect of the present invention, there is provided a main body (61) having an oil passage communicating with an oil passage (56) provided in the crankcase (31), and a cylinder hole (44) extending from the main body (61). A nozzle part (62) extending toward the piston (45) and having an oil injection port (62a), and an insertion hole provided so as to protrude from the main body part (61) and through the screwing member (64) ( The piston cooling oil injection device (60) having a fastening arm portion (63) formed with 63d) is fastened and fixed to the crankcase (31) by the screw member (64). In the mounting structure of the injection device (60), the crankcase (31) has an arm portion mounting boss (65) to which the screwing member (64) is fastened, and a main body to which the main body portion (61) is mounted. And a fastening surface (65a) of the arm portion mounting boss (65) and a body portion mounting surface (65b) of the body portion mounting hole (65f). With respect to the axial direction of the joint member (64), the fastening surface (65a) and the main body portion mounting surface (65b) are formed in planes having different heights, and the axial direction of the screwing member (64). The fastening arm portion (63) is formed along the contact surface portion (65c) of the arm portion mounting boss (65), and is connected to the piston cooling oil. The injection device (60) is fixed to the crankcase (31), and at least a part (63a) of the fastening arm portion (63) is brought into contact with the contact surface portion (65c), and the fastening One structure (63b) of the arm (63) is fastened to the fastening surface (65a).

  According to a second aspect of the present invention, the contact surface portion (65c) is formed to have a plane substantially parallel to the axis of the screwing member (64), and a plate in the fastening arm portion (63) is formed on the plane. 2. The piston cooling oil injection device mounting structure according to claim 1, wherein the part (63a) formed in a shape abuts.

  The invention according to claim 3 is characterized in that the other end portion (63c) of the fastening arm portion (63) is in pressure contact with the main body portion mounting surface (65b). It is the attachment structure of an apparatus.

  The crankcase (31) can be divided into a first case half (32) and a second case half (33), and the fastening surface (65a) is formed in the crankcase. 4. The piston cooling oil injection device mounting structure according to claim 1, wherein the piston cooling oil injection device is formed on the same plane as the dividing surface of (31).

  The invention according to claim 5 has a split surface of the crankcase (31) on the cylinder axis (G), and any one of the first case half (32) and the second case half (33). The fastening surface (65a) is formed on the same plane as the split surface of one of the crankcase halves, and the body portion is attached to the inner wall surface of the one crankcase half and away from the cylinder axis. 5. The piston cooling oil injection device mounting structure according to claim 4, wherein a surface (65b) is formed.

  The invention according to claim 6 is configured such that the crankcase (31) can be divided into a first case half (32) and a second case half (33), and the first case half (32). ) And the second case half (33) are coupled to each other by a case coupling bolt (23), a case coupling fastening boss (22) is formed, and the fastening surface (65a) has the fastening arm portion The arm mounting boss (65) having a fastening hole (65d) corresponding to the insertion hole (63d) formed in (63) is formed, and the arm mounting boss (65) is connected to the case. 5. The piston cooling oil injection device mounting structure according to claim 1, wherein the piston cooling oil injection device is provided in the vicinity of the fastening boss (22).

  The invention according to claim 7 is characterized in that the stud bolt fastening boss (24) is connected to the crankcase (31) so that the internal combustion engine component (31, 34) including the lid (35) is connected by the stud bolt (37). The arm mounting boss (65) having a fastening hole (65d) corresponding to the insertion hole (63d) formed in the fastening arm (63) is formed on the fastening surface (65a). The piston cooling oil injection device according to any one of claims 1 to 6, wherein the arm portion mounting boss (65) is provided close to the stud bolt fastening boss (24). It is a mounting structure.

  The invention according to claim 8 is configured such that the crankcase (31) can be divided into a first case half (32) and a second case half (33), and the first case half (32). ) And the second case half (33) are coupled by a case coupling bolt (23), a case coupling fastening boss (22) is formed, and the crankcase (31) has a cylinder head (35). An internal combustion engine component (31, 34) including a stud bolt fastening boss (24) is formed so that the stud bolt (37) is coupled thereto, and the fastening arm portion (63) is formed on the fastening surface. The arm mounting boss (65) having a screw hole (65e) corresponding to the insertion hole (63d) is formed, and the arm mounting boss (65) is the case coupling fastening boss (22). And the stud bolt fastening boss (24) between the case coupling fastening boss (22) and the stud bolt fastening boss (24). Be provided Te is a mounting structure of a piston cooling oil jetting apparatus of claim 1 to claim 7 wherein.

  According to a ninth aspect of the present invention, the oil passage (56) of the crankcase (31) communicates with an oil pump (50) and is connected to the main body (61) of the piston cooling oil injection device (60). 9. An oil injection device for cooling a piston according to claim 1, wherein the oil discharged from the oil pump (50) is supplied on the most upstream side before branching to another oil passage. This is the mounting structure.

  According to a tenth aspect of the present invention, the cylinder hole (44) is in a plane in which the cylinder axis (G) is orthogonal to the crank axis (C) and is either one above or below the crank axis (C). 10. The piston cooling according to claim 1, wherein the piston cooling oil injection device (60) is disposed on an offset side of the cylinder hole (44). It is the attachment structure of the oil injection device for a vehicle.

  According to the eleventh aspect of the present invention, when the piston (45) is at bottom dead center, the nozzle portion (62) and the piston (45) are superposed in the cylinder axis (G) direction, and the piston ( The piston cooling oil injection device according to any one of claims 1 to 10, wherein an escape recess (45a) for preventing interference with the nozzle portion (62) is formed at a polymerization site. It is a mounting structure.

  In claim 1, the fastening surface 65a of the arm portion mounting boss 65 in the crankcase 31 and the body portion mounting surface 65b to which the body portion 61 is attached have a height relative to the axial direction of the screw member 64. The fastening surface 65a and the body portion mounting surface 65b are connected to each other via a contact surface portion 65c along the axial direction of the screwing member 64, and the fastening arm portion 63 is formed on different planes. Formed along the contact surface portion 65c of the arm portion mounting boss 65, the piston cooling oil injection device 60 is fixed to the crankcase 31, and at least a part 63a of the fastening arm portion 63 is While being in contact with the contact surface portion 65c and one end portion 63b of the fastening arm portion 63 is fastened to the fastening surface 65a, when installing the crankcase 31 of the piston cooling oil injection device 60, The main body 61 tries to rotate with the rotation of the screw member 64. Can part 63a of the fastening arms 63 can be prevented by coming into contact with the contact face portion 65c of the arm portion mounting boss 65, favorably for positioning the piston cooling oil jetting device 60. Therefore, the oil injected from the nozzle portion 62 of the piston cooling oil injection device 60 can be made to reach the required location on the lower surface of the piston 45 with high accuracy.

  According to a second aspect of the present invention, the contact surface portion 65c is formed to have a plane substantially parallel to the axis of the screwing member 64, and the one surface formed in a plate shape in the fastening arm portion 63 is formed on the plane. When the part 63a abuts, the part 63a can be enlarged, and higher mounting accuracy can be obtained.

  According to the third aspect of the present invention, when the other end portion 63c of the fastening arm portion 63 is brought into pressure contact with the main body portion mounting surface 65b, a higher mounting accuracy of the piston cooling oil injection device 60 can be obtained.

  In claim 4, the crankcase 31 is configured to be divided into a first case half 32 and a second case half 33, and the fastening surface 65 a is formed on the same plane as the split surface of the crankcase 31. Therefore, the threading process for fastening the screwing member can be easily performed, the productivity is improved, and further, it becomes easy to secure the fastening work space of the screwing member using a tool. Since it can be performed easily, productivity is further improved.

  In Claim 5, it has the division surface of the said crankcase 31 on the cylinder axis line G, The division surface of either one of the said 1st case half body 32 and the said 2nd case half body 33, The fastening surface 65a is formed on the same plane, and the main body mounting surface 65b is formed on the inner wall surface which is the one crankcase half and away from the cylinder axis. It is possible to easily avoid interference between the piston 45 moving inside and the connecting rod 47 connected to the piston 45 and the nozzle portion 62.

  In claim 6, the crankcase 31 is configured to be divided into a first case half 32 and a second case half 33, and the first case half 32 and the second case half 33 are separated from each other. A case coupling fastening boss 22 is formed to be coupled by the case coupling bolt 23, and the fastening surface 65a has the fastening hole 65d corresponding to the insertion hole 63d formed in the fastening arm portion 63. A part mounting boss 65 is formed, and the arm part mounting boss 65 is provided in the vicinity of the case coupling fastening boss 22 so that the existing case coupling fastening boss 22 can be used to mount the arm part. The rigidity of the boss 65 can be effectively increased, the vibration of the piston cooling oil injection device 60 is suppressed, and the oil injection accuracy can be improved.

  In claim 7, a stud bolt fastening boss 24 is formed so that the internal combustion engine components 31, 34 including the rinsing head 35 are coupled to the crankcase 31 by a stud bolt 37, and the fastening arm 65 is provided with the fastening arm 65a. The arm portion mounting boss 65 having a fastening hole 65d corresponding to the insertion hole 63d formed in the portion 63 is formed, and the arm portion mounting boss 65 is provided close to the stud bolt fastening boss 24. Therefore, the rigidity of the arm mounting boss 65 can be effectively increased by using the existing stud bolt fastening boss 24, the vibration of the piston cooling oil injection device 60 is suppressed, and the oil injection accuracy is improved. Is possible.

  In claim 8, the crankcase 31 is configured to be divided into a first case half 32 and a second case half 33, and the first case half 32 and the second case half 33 are separated from each other. A case coupling fastening boss 22 is formed to be coupled by the case coupling bolt 23, and the internal combustion engine components 31, 34 including the cylinder head 35 are coupled to the crankcase 31 by the stud bolt 37. A fastening boss 24 is formed, and on the fastening surface, the arm portion mounting boss 65 having a screw hole 65e corresponding to the insertion hole 63d formed in the fastening arm portion 63 is formed, and the arm portion mounting The boss 65 is between the case coupling fastening boss 22 and the stud bolt fastening boss 24, and is provided close to the case coupling fastening boss 22 and the stud bolt fastening boss 24. Existing The rigidity of the arm mounting boss 65 can be effectively increased by utilizing the screw coupling fastening boss 22 and the stud bolt fastening boss 24, and the vibration of the piston cooling oil injection device 60 is suppressed, and the oil injection Accuracy is improved.

  In claim 9, the oil passage 56 of the crankcase 31 communicates with an oil pump 50, and oil discharged from the oil pump 50 is supplied to the main body 61 of the piston cooling oil injection device 60. Since the oil is supplied on the most upstream side without branching to the oil passage, high-pressure oil flows into the piston cooling oil injection device 60, and the oil injected from the nozzle section 62 can reach the bottom surface of the piston 45 at high speed. The required part can be efficiently cooled with high accuracy.

  In claim 10, the cylinder hole 44 is provided so that the cylinder axis G is in a plane perpendicular to the crank axis C and is offset to either the upper or lower side with respect to the crank axis C, By disposing the piston cooling oil injection device 60 on the offset side of the cylinder hole 44, the piston cooling oil injection device 60 can be disposed on the offset side of the cylinder hole 44. The arrangement space of the device 60 is widened, and interference between the piston cooling oil injection device 60, the connecting rod 47 and the crank web is effectively avoided.

  In claim 11, when the piston 45 is at the bottom dead center, the nozzle portion 62 and the piston 45 are superposed in the cylinder axis G direction, and the piston 45 has the nozzle portion 62 at the superposition site. By forming the relief recess 45a that prevents interference with the nozzle portion, the nozzle portion can be disposed close to the piston. Therefore, the oil injected from the oil injection port 62a of the nozzle part 62 can reach the required portion on the bottom surface of the piston 45 with high accuracy, and the piston can be efficiently cooled.

1 is a left side view of a scooter type motorcycle 1 having a structure for mounting a piston cooling oil injection device 60 of the present invention. FIG. FIG. 2 is an explanatory diagram illustrating an oil supply system of a single-cylinder internal combustion engine with an overhead valve 30 equipped with a mounting structure for a piston cooling oil injection device 60. 2 is a longitudinal plan view of a single-cylinder internal combustion engine 30 with an overhead valve equipped with a mounting structure for a piston cooling oil injection device 60. FIG. 4 is an enlarged longitudinal plan view of a main part of the mounting structure of the piston cooling oil injection device 60. FIG. 2 is a vertical elevational view of a single-cylinder internal combustion engine 30 with an overhead valve equipped with a mounting structure for a piston cooling oil injection device 60. FIG. FIG. 3 is a cross-sectional view of a cylinder block 34 cut in the vertical direction along a mating surface of a right crankcase 33 to which a piston cooling oil injection device 60 is attached. FIG. 7 is a cross-sectional view illustrating a state where the piston cooling oil injection device 60 is removed in FIG. 6. In the front end view of the right crankcase 33 as viewed from the front of the vehicle body to the rear of the vehicle body, portions indicated by broken lines 45 and 58 are drawings showing the piston 45 and the oil groove 58 as seen through. 4 is a cross-sectional view of the cylinder block 34, the cylinder head 35, and the head cover 36 cut along a plane passing through two left and right stud bolts 37a, 37b of the cylinder block 34. FIG. FIG. 5 is a cross-sectional view of the right crankcase 33 cut along a plane from the front of the vehicle body toward the rear of the vehicle body.

  A first embodiment of the piston cooling oil injection device mounting structure in the internal combustion engine according to the present invention shown in FIGS. 1 to 10 will be described below.

  In the scooter type motorcycle 1 shown in FIG. 1, a vehicle body front portion 3 and a vehicle body rear portion 4 of a vehicle body are connected via a floor portion 5, and a down tube 7 is connected from a head pipe 6 of the vehicle body front portion 3. The front ends of a pair of left and right main pipes 8 are integrally connected to the lower left and right sides of the lower end, and extend to the left and right sides and extend rearward. Both rear ends of the main pipe 8 are integrally joined to the front ends of the side rails 9 that are bent in a U shape in a planar shape, and the angle with respect to the horizontal plane is reduced at a required location.

  In the rear part 4 of the vehicle body, a seat 10 is disposed above the side rails 9, and a steering shaft (not shown) is fitted in the head pipe 6 so as to be able to turn left and right in the front part 3 of the vehicle body. A handle 11 is integrally mounted, and a front fork 12 is integrally coupled to the lower end of the steering shaft, and a front wheel 13 is pivotally supported on the lower end of the front fork 12.

  Further, a bracket 15 is integrally attached to a bent portion of the main pipe 8, and a hanger bracket 21 provided at a lower portion of the power unit 20 is pivotally attached to the bracket 15 via a link 16 so as to be swingable up and down.

  Furthermore, the power unit 20 mounted on the scooter type motorcycle 1 oriented in the longitudinal direction of the vehicle body includes a water-cooled single-cylinder internal combustion engine 30 with an overhead valve oriented forward of the vehicle body and a belt type The members constituting the outer shell structure of the single-cylinder internal combustion engine 30 with an overhead valve and the belt-type continuously variable transmission 80, which are composed of the step transmission 80, pass through the center line of the piston hole, which will be described later, and As shown in FIGS. 2 and 9, a cylinder block 34 and a cylinder are sequentially formed on a crankcase 31 composed of left and right crankcases 32 and 33 that are divided into two in a direction perpendicular to the center line of the crankshaft 38 that is oriented in the direction. A head 35 and a cylinder head cover 36 are stacked, and a stud bolt 37 that passes through the cylinder block 34 from the cylinder head 35 and is screwed to the crank case 31 allows the crank case 31, the cylinder block 34, The cylinder head 35 is integrally formed, the cylinder head cover 36 is integrally coupled to the cylinder head 35 by bolts 38, and the crankcase 31 includes a plurality of bolts in which the left and right crankcases 32 and 33 include bolts 23 (see FIG. 6). Combined at 23 and integrated.

  The left and right crankshafts 40 and 41, which are pivotally supported by the left crankcase 32 and the right crankcase 33 via bearings 43, respectively, are integrally connected to each other by fitting the crankpins 42. The piston pin 46 of the piston 45 slidably fitted in the cylinder hole 44 of the cylinder block 34 and the crank pin 42 of the crankshaft 39 are connected to each other via both ends of the connecting rod 47, and are substantially horizontal. The crankshaft 39 is rotationally driven in conjunction with the back and forth reciprocation of the piston 45 fitted in the cylinder hole 44 oriented in the direction.

  As shown in FIG. 2, the left crankcase 32 is provided with a belt-type continuously variable transmission 80, the left crankshaft 40 is provided with a drive pulley 82, and the right crankcase 33 is further to the right. An ACG starter 48 is provided on the right crankshaft 41 protruding in the direction.

  Further, as shown in FIG. 2, in the right crankcase 33 of the crankcase 31, an oil pump 50 driven by an oil pump driven gear 52 meshed with an oil pump drive gear 51 integral with the right crankshaft 41 is provided. The oil in the oil pan 54 disposed and positioned below the crank chamber 49 is filtered by the oil strainer screen 55 and then sucked into the oil pump 50.

  In the space formed by the cylinder head 35 and the cylinder head cover 36, a valve operating mechanism 76 for opening / closing an intake / exhaust valve provided in the cylinder head 35 is disposed and integrated with the right crankshaft 41. An endless chain 74 is stretched over the provided drive sprocket 72 and a driven sprocket 73 integral with the rotary shaft 71 of the valve operating mechanism 76, and the single-cylinder internal combustion engine 30 with an overhead valve is in an operating state. When the crankshaft 39 is rotated, the valve mechanism 76 is activated through the transmission system of the drive sprocket 72, the driven sprocket 73, and the endless chain 74. -The exhaust valve opens and closes, intake air is supplied into the cylinder hole 44, and the single-cylinder internal combustion engine 30 with an overhead valve enters an operating state.

  Further, the left crankcase 32 of the crankcase 31 extends rearward as the main outer shell structure of the belt-type continuously variable transmission 80 shown in FIG. 1, and a continuously variable transmission cover is provided on the left side of the left crankcase 32. In the belt-type continuously variable transmission 80 formed by the left crankcase 32 and the continuously variable transmission cover 81, the drive pulley 82 of the belt-type continuously variable transmission 80 is attached to the left crankshaft 40. A driven pulley 83 (see FIG. 1) is provided at the rear of the vehicle body. An endless V-belt 84 is bridged between the drive pulley 82 and the driven pulley 83, and the driven pulley 83 is connected via a speed reducer 85. When the rotational speed of the crankshaft 39 of the single cylinder internal combustion engine 30 with overhead valve increases, the gear ratio of the belt type continuously variable transmission 80 is automatically changed in conjunction with this. The rotational speed of the rear wheel 14 is accelerated It has become the jar.

  Next, the oil supply system will be described.

  In FIG. 2, an oil pump drive gear 51 is integrally mounted on the right crankshaft 41 and is located on the right side of the drive sprocket 72 that drives the valve mechanism 76, and the oil pump 50 is driven by the oil pump 50. A gear 52 is engaged, and a rotor 53 is integrally coupled to the oil pump driven gear 52.When the overhead cylinder single cylinder internal combustion engine 30 is in an operating state, the oil pump 50 is driven to rotate, The oil is filtered by the oil strainer screen 55 and then sucked into the oil pump 50. The oil pressurized by the oil pump 50 passes through the oil passage 56 and meets the mating surface of the right crankcase 33 and the cylinder block 34. To reach.

  An opening of an oil passage 56, a first stud bolt insertion hole 25a, and a second stud bolt insertion hole 25b are formed on the front end surface of the right crankcase 33 shown in FIG. 8 as viewed from the front of the vehicle body. A stud bolt insertion hole (not shown) is formed in the left crankcase 32 in the same positional relationship as the right crankcase 33, and a stud bolt 37 that penetrates the cylinder head 35 and the cylinder block 34 from the front to the rear. Are screwed to the left and right crankcases 32, 33.

  A curved groove 58 shown by a broken line in FIG. 8 is formed on the base end surface of the cylinder block 34. One end 58a of the groove 58 communicates with the oil passage 56, and the oil groove 58 is advanced upward. The first stud bolt insertion hole 25a is detoured to the left (right in the drawing) and then communicated with the crank bearing oil passage 57, and the other end 58b of the oil groove 58 communicates with the second stud bolt insertion hole 25b. It has become.

  Further, a mounting structure of the main body 61 in the piston cooling oil injection device 60 will be described.

  On the inner surface of the right crankcase 33 of the crankcase 31 in the single-cylinder internal combustion engine 30 with an overhead valve, as shown in FIG. 4, an arm mounting boss 65 projects toward the cylinder axis G. The fastening surface 65a is formed in a shape along a plane perpendicular to the crank axis C and passing through the cylinder axis G. The fastening surface 65a is parallel to the fastening surface 65a at a position positioned to the right with a predetermined distance from the fastening surface 65a. The main body mounting surface 65b is formed, the fastening surface 65a, a contact surface portion 65c perpendicular to the main body mounting surface 65b is formed, and a hole 65d is formed to the right from the fastening surface 65a. A screw hole 65e is provided in the hole 65d.

  4 is a part of the deformed Z-shaped fastening arm portion 63 shown in FIG. 4, and the arm portion side portion 63a located in the center is in close contact with the contact surface portion 65c of the arm portion mounting boss 65, and the fastening arm portion. One end 63b, which is one end of 63, can be in close contact with the fastening surface 65a of the boss 65 for attaching the arm, and the other end 63c, which is the other end of the fastening arm 63, can be in close contact with the main body attaching surface 65b. An insertion hole 63d through which the shaft portion of the screwing member 64 can pass is formed in the arm portion side one end portion 63b of the fastening arm portion 63, and a body portion is formed in the other end portion 63c of the fastening arm portion 63. 61 passes through, and the main body 61 is integrally attached to the other end 63c by brazing or the like, and an O-ring 61c is fitted in a portion near the tip of the main body 61.

  A nozzle portion 62 projects from the base end portion of the main body portion 61. When the main body portion 61 is mounted on the arm portion mounting boss 65 shown in FIG. The oil communication passage 61a and the opening 61b communicate with the oil passage 56, and the oil discharged from the oil pump 50 is sent to the nozzle portion 62 through the oil passage 56, the opening 61b and the oil communication passage 61a, and the nozzle portion. As shown in FIG. 6, oil is injected from the oil injection port 62 a at the tip of 62 toward the lower surface central portion 45 b of the piston 45 as indicated by an oil injection path F.

  Since the piston cooling oil injection device 60 is configured as described above, the main body 61 is fitted into the injection device main body mounting hole 65f of the arm mounting boss 65, and a part 63a of the fastening arm 63 is formed. In a state where the screw member 64 that contacts the contact surface portion 65c of the arm mounting boss 65 and passes through the insertion hole 63d of the fastening arm portion 63 is screwed into the screw hole 65e of the arm mounting boss 65, it is screwed. Even when a large torque is applied to the arm side end 63b of the fastening arm 63 by screwing the member 64, the fastening surface 65a of the arm mounting boss 65 and the arm side end 63b of the fastening arm 63 Not only the frictional force but also the fastening arm portion 63 against the arm mounting boss 65 by the position restriction due to the contact between the contact surface portion 65c of the arm mounting boss 65 and the arm portion side portion 63a of the fastening arm portion 63. As a result of being prevented from turning and the main body part 61 being integrally coupled to the fastening arm part 63, there is no fear that the main body part 61 will turn, and further, the main body part 61 is the injection device main body. Since the mounting hole 65f is stably mounted without falling down, the sealing performance between the main body 61 and the injection device main body mounting hole 65f by the O-ring 61c can be kept uniform. The oil jetted from the oil jet port 62a of the nozzle part 62 is accurately jetted to a required location, and the oil is effectively supplied to the center part 45b of the lower surface of the piston 45. The top part of the piston 45 having a large heat load is effectively Can be cooled.

  As shown in FIG. 8, the remaining oil sent from the oil passage 56 to the piston cooling oil injection device 60 passes through the oil groove 58 from the one end 58a as shown in FIG. Then, it flows into the crank pin 42 from the crank bearing oil passage 57 and is injected into the cylinder hole 44 from between the large diameter end of the crank pin 42 and the connecting rod 47, and the contact portion between the cylinder hole 44 and the piston pin 46 is lubricated. The

  Further, the remaining oil flowing through the oil groove 58 reaches the second stud bolt through hole 57b and is supplied to the valve mechanism 76 as shown in FIG.

  As shown in FIG. 4, the mounting structure of the piston cooling oil injection device 60 fastened and fixed to the crankcase 31 by the screwing member 64 includes an oil passage communicating with the oil passage 56 provided in the crankcase 31. A main body part 61, a nozzle part 62 that extends from the main body part 61 toward the piston 45 in the cylinder hole 44 and has an oil injection port 62a, and protrudes from the main body part 61 and is inserted through the screwing member 64 The mounting structure of the piston cooling oil injection device 60 that is fastened and fixed to the crankcase 31 is configured by a screw member 64.

  The fastening surface 65a of the arm portion mounting boss 65 in the crankcase 31 and the body portion mounting surface 65b to which the body portion 61 is mounted are formed on different planes with respect to the axial direction of the screw member 64. The fastening surface 65a and the main body portion mounting surface 65b are connected via a contact surface portion 65c along the axial direction of the screwing member 64, and the fastening arm portion 63 is used for mounting the arm portion. The piston cooling oil injection device 60 is formed along the contact surface portion 65c of the boss 65, and at least a part 63a of the fastening arm portion 63 is fixed to the contact surface portion 65c while being fixed to the crankcase 31. Since the one end portion 63b of the fastening arm portion 63 is fastened to the fastening surface 65a, the screw engagement member 64 of the piston cooling oil injection device 60 is attached when the crankcase 31 is attached. As the main body 61 tries to rotate with the rotation, the fastening arm 63 Some 63a it is possible to prevent by abutting the contact face portion 65c of the arm portion mounting boss 65, the positioning of the piston cooling oil jetting device 60 can be performed well. Therefore, the oil injected from the nozzle portion 62 of the piston cooling oil injection device 60 can be made to reach the required location on the lower surface of the piston 45 with high accuracy.

  The contact surface portion 65c is formed to have a plane substantially parallel to the axis of the screwing member 64, and the portion 63a formed in a plate shape in the fastening arm portion 63 contacts the plane. Part 63a can be enlarged, and higher mounting accuracy can be obtained.

  By attaching the other end portion 63c of the fastening arm portion 63 to the main body portion attachment surface 65b, higher attachment accuracy of the piston cooling oil injection device 60 can be obtained.

  Referring also to FIG. 8, the crankcase 31 is configured to be split into a first case half 32 and a second case half 33, and the fastening surface 65 a is on the same plane as the split surface of the crankcase 31. Therefore, the threading process for fastening the screwing member can be easily performed, the productivity is improved, and it is easy to secure the work space for fastening the screwing member using a tool. Since the work can be easily performed, productivity is further improved.

  The crankcase 31 has a split surface on the cylinder axis G, and is on the same plane as the split surface of one of the first case half 32 and the second case half 33. A piston that moves in the crankcase 31 by forming the fastening surface 65a and forming the main body portion mounting surface 65b on the inner wall surface of the one crankcase half and away from the cylinder axis. Interference between the connecting rod 47 connected to the piston 45 and the piston 45 and the nozzle portion 62 can be easily avoided.

  5 and 7, the crankcase 31 is configured to be divided into a first case half 32 and a second case half 33, and the first case half 32 and the second case half 33 are divided. A case coupling fastening boss 22 is formed so that the body 33 is coupled with the case coupling bolt 23, and a fastening hole 65d corresponding to the insertion hole 63d formed in the fastening arm portion 63 is formed on the fastening surface 65a. The arm portion mounting boss 65 is formed, and the arm portion mounting boss 65 is provided in the vicinity of the case coupling fastening boss 22 so that the existing case coupling fastening boss 22 is used. The rigidity of the arm portion mounting boss 65 can be effectively increased, the vibration of the piston cooling oil injection device 60 is suppressed, and the oil injection accuracy can be improved.

  Further, a stud bolt fastening boss 24 is formed so that the internal combustion engine components 31, 34 including the rinsing head 35 are coupled to the crankcase 31 by the stud bolt 37, and the fastening surface 65a is connected to the fastening arm portion 63. The arm portion mounting boss 65 having a fastening hole 65d corresponding to the formed insertion hole 63d is formed, and the arm portion mounting boss 65 is provided close to the stud bolt fastening boss 24. The existing stud bolt fastening boss 24 can be used to effectively increase the rigidity of the arm mounting boss 65, thereby suppressing vibration of the piston cooling oil injection device 60 and improving oil injection accuracy. Become.

  Further, the crankcase 31 is configured to be divided into a first case half 32 and a second case half 33, and the first case half 32 and the second case half 33 are connected to a case coupling bolt. 23, a case coupling fastening boss 22 is formed, and an internal combustion engine component 31, 34 including a cylinder head 35 is connected to the crankcase 31 by a stud bolt 37 so as to be coupled by a stud bolt fastening boss 24. The arm attachment boss 65 having a screw hole 65e corresponding to the insertion hole 63d formed in the fastening arm portion 63 is formed on the fastening surface, and the arm attachment boss 65 is The existing case is provided between the case coupling fastening boss 22 and the stud bolt fastening boss 24 and in proximity to the case coupling fastening boss 22 and the stud bolt fastening boss 24. The joint fastening boss 22 and the stud bolt fastening boss 24 can be used to effectively increase the rigidity of the arm mounting boss 65, thereby suppressing the vibration of the piston cooling oil injection device 60 and improving the oil injection accuracy. To do.

  Referring to FIG. 2, the oil passage 56 of the crankcase 31 communicates with an oil pump 50, and the oil discharged from the oil pump 50 is supplied to the main body 61 of the piston cooling oil injection device 60. Is supplied on the most upstream side without branching to the other oil passages 57, 57b, so that high-pressure oil flows into the piston cooling oil injection device 60, and the oil injected from the nozzle portion 62 is at a high speed. The required part can be efficiently cooled with high accuracy.

  Referring to FIG. 6, the cylinder hole 44 is offset in a plane where the cylinder axis G is orthogonal to the crank axis C and on either side of the crank axis C (downward in FIG. 6). By arranging the piston cooling oil injection device 60 on the offset side of the cylinder hole 44, the piston cooling oil injection device 60 can be arranged on the offset side of the cylinder hole 44. Thus, the arrangement space of the piston cooling oil injection device 60 is widened, and interference between the piston cooling oil injection device 60, the connecting rod 47 and the crank web is effectively avoided.

  Referring to FIG. 10, when the piston is at the bottom dead center, the lowermost end of the piston is configured to be located below (the rear side in FIG. 10) below the uppermost end of the nozzle portion 62. When the piston 45 is at the bottom dead center, the nozzle portion 62 and the piston 45 are superposed in the cylinder axis G direction. The piston 45 is formed with a relief recess 45a that prevents interference with the nozzle portion 62 at the overlapping portion, that is, a shape in which a part of the lower end of the piston is notched, so that the nozzle portion is disposed close to the piston. Can be done. Therefore, the oil injected from the oil injection port 62a of the nozzle part 62 can reach the required portion on the bottom surface of the piston 45 with high accuracy, and the piston can be efficiently cooled.

  In this embodiment, an example in which an oil injection device for cooling a piston is attached to an internal combustion engine of a scooter type motorcycle is shown, but this is not restrictive, and other motorcycles, motorcycles, and buggies are included. Application to riding type vehicles is also possible.

22 ... Clamping boss for case coupling, 23 ... Case coupling bolt, 24 ... Stud bolt fastening boss,
31 ... Crankcase, 32 ... Left crankcase, 33 ... Right crankcase, 34 ... Cylinder block, 35 ... Cylinder head, 37 ... Stud bolt, 37a ... First stud bolt,
44 ... Cylinder hole, 45 ... Piston, 45a ... Relief recess,
50 ... oil pump, 56 ... oil passage,
60 ... Oil injection device for cooling the piston, 61 ... Main body, 62 ... Nozzle, 62a ... Oil injection port, 63 ... Fastening arm, 63a ... Part, 63b ... One end, 63c ... Other end, 63d ... Insertion 64, screw member, 65 ... arm mounting boss, 65a ... fastening surface, 65b ... main body mounting surface, 65c ... contact surface, 65e ... screw hole, 65f ... injection device main body mounting hole,
G: Cylinder axis, C: Crank axis.

Claims (11)

A main body (61) having an oil passage communicating with an oil passage (56) provided in the crankcase (31), and extending from the main body (61) toward the piston (45) in the cylinder hole (44). A fastening arm formed with a nozzle part (62) that protrudes and has an oil injection port (62a), and an insertion hole (63d) that protrudes from the main body part (61) and passes through the screwing member (64) An oil injection device (60) for cooling the piston comprising a portion (63),
In the mounting structure of the piston cooling oil injection device (60) fastened and fixed to the crankcase (31) by the screwing member (64),
The crankcase (31) is provided with an arm portion mounting boss (65) to which the screwing member (64) is fastened, and a main body portion mounting hole (65f) to which the main body portion (61) is mounted. The fastening surface (65a) of the arm portion mounting boss (65) and the body portion mounting surface (65b) of the body portion mounting hole (65f) are high in the axial direction of the screwing member (64). The fastening surface (65a) and the main body portion mounting surface (65b) are formed through different contact surfaces (65c) along the axial direction of the screw member (64). Concatenated,
The fastening arm portion (63) is formed along the contact surface portion (65c) of the arm portion mounting boss (65), and the piston cooling oil injection device (60) is attached to the crankcase (31). In a fixed state, at least a part (63a) of the fastening arm portion (63) is brought into contact with the contact surface portion (65c), and one end portion (63b) of the fastening arm portion (63) is fastened. A piston cooling oil injection device (60) mounting structure characterized by being fastened to a surface (65a).   The abutment surface portion (65c) is formed to have a plane substantially parallel to the axis of the screwing member (64), and the portion formed in a plate shape in the fastening arm portion (63) on the plane. The structure for mounting an oil injection device for cooling a piston according to claim 1, wherein (63a) abuts.   3. The piston cooling oil injection device mounting structure according to claim 2, wherein the other end portion (63c) of the fastening arm portion (63) is in pressure contact with the main body portion mounting surface (65b).   The crankcase (31) is configured to be split into a first case half (32) and a second case half (33), and the fastening surface (65a) is the same as the split surface of the crankcase (31). The mounting structure for an oil injection device for cooling a piston according to any one of claims 1 to 3, wherein the mounting structure is formed on a surface.   A split surface of the crankcase (31) is provided on the cylinder axis (G), and the crankcase half of one of the first case half (32) and the second case half (33) is provided. The fastening surface (65a) is formed on the same plane as the dividing surface, and the main body mounting surface (65b) is formed on the inner wall surface that is the one half of the crankcase and is separated from the cylinder axis. The mounting structure for an oil injection device for cooling a piston according to claim 4. The crankcase (31) is configured to be divided into a first case half (32) and a second case half (33), and the first case half (32) and the second case half. (33) and a case coupling fastening boss (22) are formed to be coupled with the case coupling bolt (23),
The fastening surface (65a) is formed with the arm portion mounting boss (65) having a fastening hole (65d) corresponding to the insertion hole (63d) formed in the fastening arm portion (63). 5. The piston cooling oil injection device mounting structure according to claim 1, wherein the arm mounting boss (65) is provided in the vicinity of the case coupling fastening boss (22). . A stud bolt fastening boss (24) is formed so that an internal combustion engine component (31, 34) including a cylinder head (35) is connected to the crankcase (31) by a stud bolt (37),
The fastening surface (65a) is formed with the arm portion mounting boss (65) having a fastening hole (65d) corresponding to the insertion hole (63d) formed in the fastening arm portion (63). 7. The piston cooling oil injection device mounting structure according to claim 1, wherein the arm portion mounting boss (65) is provided close to the stud bolt fastening boss (24).   The crankcase (31) is configured to be divided into a first case half (32) and a second case half (33), and the first case half (32) and the second case half. The internal combustion engine component (31) is formed with a case coupling fastening boss (22) and the crankcase (31) including a cylinder head (35) to be coupled with the case coupling bolt (23). , 34) is formed with a stud bolt fastening boss (24) to be coupled by a stud bolt (37), and the fastening surface has an insertion hole (63d) formed in the fastening arm portion (63). The arm mounting boss (65) having a corresponding screw hole (65e) is formed, and the arm mounting boss (65) includes the case coupling fastening boss (22) and the stud bolt fastening boss (24 Between the case coupling fastening boss (22) and the stud bolt fastening boss (24). Mounting structure of the piston cooling oil jetting apparatus of claim 1 to claim 7, wherein the.   The oil passage (56) of the crankcase (31) communicates with an oil pump (50), and the oil pump (50) is connected to the main body (61) of the piston cooling oil injection device (60). 9. The structure for mounting an oil injection device for cooling a piston according to claim 1, wherein the oil discharged from the pump is supplied on the most upstream side before branching to another oil passage.   The cylinder hole (44) is provided so that the cylinder axis (G) is in a plane perpendicular to the crank axis (C) and is offset to either the upper or lower side with respect to the crank axis (C). 10. The piston cooling oil injection device mounting structure according to claim 1, wherein the piston cooling oil injection device (60) is disposed on an offset side of the cylinder hole (44).   When the piston (45) is at bottom dead center, the nozzle portion (62) and the piston (45) are superposed in the direction of the cylinder axis (G), and the piston (45) 11. The piston cooling oil injection device mounting structure according to claim 1, further comprising a relief recess (45a) for preventing interference with the nozzle portion (62).

Images