JP5906164B2 - Oil pump - Google Patents

Description

  The present invention relates to an oil pump structure for supplying lubricating oil to an internal combustion engine.

  In a conventional oil pump, a pin is inserted into one side of the oil pump shaft that engages with the inner rotor, and the pin is fitted into a groove formed in the inner rotor, so that the rotational force of the oil pump shaft is controlled by the inner rotor. And the movement of the oil pump shaft in the axial center line direction is restricted. However, in such an oil pump, even if an attempt is made to reduce the size of the oil pump, it is necessary to ensure the size of the inner rotor relative to the pins in order to ensure the rigidity of the inner rotor. It was difficult to achieve (see Patent Document 1).

  In order to overcome such difficulties, the oil pump shaft is supported by the crankcase and the crankcase cover with the length of the oil pump shaft corresponding to the distance between the crankcase and the crankcase cover. Accordingly, an oil pump that restricts movement of the oil pump shaft in the axial center line direction has been used. However, the length of the oil pump shaft becomes longer, and the oil pump shaft is pivotally supported by the crankcase and the crankcase cover, which restricts the arrangement of the oil pump and other parts around the oil pump. (See Patent Document 2).

Japanese Patent No. 2824413 Japanese Patent No. 2760693

  The present invention has been made in view of the above-described conventional problems, and it is possible to reduce the size of the oil pump while restricting the movement of the oil pump shaft in the axial center line direction and ensuring the rigidity of the inner rotor. It is possible to provide an oil pump that is possible and further eliminates restrictions on the arrangement of the oil pump and other parts around the oil pump, and improves the degree of freedom in the design of the internal combustion engine

  In order to achieve the above object, the invention according to claim 1 includes an outer rotor (51), an inner rotor (52), an oil pump shaft (53) fitted into the inner rotor (52), In the oil pump (50) provided with the oil pump housing (54) for housing the outer rotor (51), the oil pump (50) covers the oil pump housing (54) and has a diameter of the oil pump shaft (53). And a thick first lid member (55) for supporting the axial force of the oil pump shaft (53) and the oil pump housing (54), The oil pump shaft (53) includes a second lid member (56) having a unique shape hole (56a) formed so that a part of the diameter hole (56b) and the small diameter hole (56c) overlap each other. A groove (53a) that engages with the small-diameter hole (56c) of the second lid member (56) is formed over the circumferential direction, The oil pump shaft (53) is supported by the oil pump housing (54) and the first lid member (55), and the small diameter hole (56c) of the second lid member (56) is formed by the oil pump shaft ( 53) is engaged with the groove portion (53a), and the first lid member (55) and the second lid member (56) are fastened to the oil pump housing (54) by tightening together. It is an oil pump characterized by

  According to a second aspect of the present invention, in the oil pump according to the first aspect, the first lid member (55) is formed thicker than the second lid member (56). is there.

  According to a third aspect of the present invention, in the oil pump according to the first or second aspect, the inner rotor insertion side of the oil pump shaft (53) is a cross-section with a part of a circular cross-section cut away. A fitting portion (53b) having a shape, and an insertion hole (52b) having the same shape as the cross-sectional shape of the fitting portion (53b) of the oil pump shaft (53) at the rotation center of the inner rotor (52). The groove portion (53a) of the oil pump shaft (53) is attached to the small diameter hole (56c) of the second lid member (56) and is retained so that the oil pump shaft (53) The circular hole (55a) of the first lid member (55) is inserted, and the fitting portion (53b) of the oil pump shaft (53) is fitted into the fitting hole (52b) of the inner rotor (52). It is a characteristic.

According to a fourth aspect of the present invention, in the oil pump according to any one of the first to third aspects, the oil pump (50) includes a crankshaft (32), a crankcase (20), Used in an internal combustion engine (E) having a crankcase cover (60) and a clutch (C). The internal combustion engine (E) has the crankshaft (32) oriented in the left-right direction and the cylinder shaft tilted forward. Mounted on a vehicle, the oil pump housing (54) is formed integrally with the crankcase cover (60), and the crankcase cover (60) has a clutch housing recess (63) for housing the clutch (C). A bearing hole (64) for receiving the crankshaft (32) is formed inside the crankcase cover (60) and positioned in front of the clutch housing recess (63), and the oil pump housing (54) is forward of the clutch housing recess (63). An oil pump drive provided below the bearing hole (64) and engaged with the oil pump shaft (54) and rotated integrally when the crankcase cover (60) is attached to the crankcase (20). The gear (58) is engaged with a drive gear (39) fitted to the crankshaft (32).

According to a fifth aspect of the present invention, in the oil pump according to any one of the first to fourth aspects, the internal combustion engine (E) is configured such that the crankshaft (32) is oriented in the left-right direction and the cylinder shaft the mounted on a vehicle tilted forward, the comprises a crankshaft (32) disc-shaped centrifugal oil filter attached to (26), the centrifugal oil filter (26), pivotally supporting the crankshaft (32) The first lid member (55) and the second lid member (56) are attached between the main bearing (38) and the drive gear (39), and the oil pump housing ( 54) and at least a part of the first lid member (55) and the second lid member (56) overlaps the centrifugal oil filter (27) or the drive gear (39) in a side view. It is a characteristic.

  According to the first aspect of the present invention, the oil pump shaft can be easily prevented from coming off, the inner rotor can be secured, and the oil pump can be downsized. It is possible to improve the degree of freedom in designing the internal combustion engine by eliminating the restriction on the arrangement of these parts.

  According to the second aspect of the invention, in addition to the effect of the oil pump of the first aspect, the axial force of the oil pump shaft is received by the thick first lid member, and the oil pump is received by the second lid member. By positioning the shaft in the axial direction, the oil pump shaft can be easily held in the oil pump housing.

  According to the third aspect of the present invention, in addition to the effect of the oil pump according to the first or second aspect, the rotation prevention between the oil pump shaft and the inner rotor and the oil pump shaft can be achieved with a compact structure. The small oil pump can be easily and compactly attached.

  According to the invention of claim 4, in addition to the effect of the oil pump of any one of claims 1 to 3, the oil pump is attached using a dead space in the internal combustion engine. The internal combustion engine can be downsized and the oil pump can be easily assembled.

  According to invention of Claim 5, in addition to the effect of the oil pump of Claim 1 or Claim 4, the 1st cover member and the 2nd cover member are enlarged, and it is the space | interval of a volt | bolt. It is possible to withstand the rotational force of the oil pump by taking a wide range, and to make effective use of the dead space and make the internal combustion engine compact.

1 is a right side view of a motorcycle equipped with an internal combustion engine equipped with an oil pump according to the present invention. It is a right view of the internal combustion engine of FIG. It is principal part sectional drawing of an internal combustion engine. It is a disassembled perspective view of an oil pump. It is the perspective view which showed the oil pump shaft. It is a top view of the 2nd lid member. It is the top view which looked at the right crankcase cover from the crankcase side.

  An embodiment of the present invention will be described below with reference to FIGS.

  FIG. 1 shows a motorcycle equipped with an oil pump for an internal combustion engine to which the present invention is applied. In the present specification, the forward and backward directions of the motorcycle are defined as the front, and the front, rear, left and right are defined with reference to the posture facing the front.

  The body frame of the motorcycle 1 has a main frame 3 extending rearward from the head pipe 2 and extending obliquely downward, and a down frame 4 extending obliquely downward from the head pipe 2. A seat rail 5 is attached to a portion of the main frame 3 that extends rearward and is bent so as to extend obliquely downward, and a portion in the middle of the seat rail 5 and a lower portion of the main frame 3 are connected by a stay 6. ing.

  A front fork 7 is pivotally supported on the head pipe 2, a front wheel 8 is pivotally supported at the lower end thereof, a front fender 9 is provided above the front wheel 8, and the handle 10 is expanded to the left and right above the head pipe 2. Is provided.

  A fuel tank 11 is mounted on the main frame 3 so as to straddle from above, and a seat 12 is attached behind the fuel tank 11 so as to straddle the seat rail 5 from above. A pivot 14 that pivotally supports a rear fork 13 is provided near the lower center of the main frame 3. A front end is pivotally supported by the pivot 14 of the main frame 3, a rear fork 13 extends rearward, and a rear wheel 14 is pivotally supported at the rear end.

  The internal combustion engine E mounted on the vehicle body frame is a four-cycle one-cylinder internal combustion engine E, and is suspended between the main frame 3 and the down frame 4 in a posture in which the cylinder is inclined.

  The internal combustion engine E is a four-stroke internal combustion engine. As shown in FIG. 2, a cylinder block 21, a cylinder head 22 and a head cover 23 are sequentially stacked and fastened integrally above the crankcase 20. A right crankcase cover 60 and a left crankcase cover 70 are fastened to the left and right.

  The cylinder block 20 is formed with a cylinder bore 30 penetrating in an oblique direction, and a piston 31 is fitted in the bore 30. The crankshaft 32 is rotatably supported by left and right main bearings 38 disposed in the crankcase 20, and the crankpin 33 of the crankshaft 32 is connected to the piston 31 via a connecting rod 34.

  The cylinder head 22 is provided with a combustion chamber 35. The combustion energy in the combustion chamber 35 of the internal combustion engine E is converted into the kinetic energy of the piston 31 so that the piston 31 is moved up and down, and the crankshaft 32 is connected via the connecting rod 34. Is driven to rotate.

  The crankshaft 32, the main shaft 36, and the countershaft 37 are disposed so that the axial directions thereof are parallel to each other, and are respectively rotatably supported by bearings provided in the crankcase 20. An interruptable clutch C is disposed at the end of the main shaft 36. The rotational driving force of the crankshaft 25 is transmitted to the main shaft 36 via the clutch C, and further includes a transmission mechanism M having a gear transmission mechanism. Via the counter shaft 37.

  As shown in FIG. 3, an oil reservoir formed integrally with the inside of the right crankcase cover 60 and the left crankcase cover 70 that stores lubricating oil that lubricates the internal combustion engine E is stored in the lower portion of the crankcase 20. A strainer 25 is disposed above the oil reservoir 24, and the oil reservoir 24 and the oil pump 50 are communicated with each other via the strainer 25.

  As shown in FIG. 2 and FIG. 3, an oil pump 50 is disposed inside the right crankcase cover 60, located at the lower right side of the internal combustion engine E.

  As shown in FIG. 4, the oil pump 50 is a trochoid pump, and includes an outer rotor 51, an inner rotor 52, an oil pump shaft 53, an oil pump housing 54, a first lid member 55, a second lid member 56, and a removal. A stop pin 57 and an oil pump drive gear 58 are provided.

  The outer rotor 51 has a cylindrical shape with a thick outer shape, and an inner tooth 51a is formed on the inner peripheral surface thereof. An inner rotor 52 having outer teeth 52a meshing with the inner teeth 51a of the outer rotor 51 is formed inside the outer rotor 51 so that the inner teeth 51a and the outer teeth 52a are engaged with each other in the outer rotor 51. Inserted. An insertion hole 52 b into which the oil pump shaft is inserted is formed at the rotation center of the inner rotor 52.

  An oil pump housing 54 is formed integrally with the crankcase cover 60 inside the right crankcase cover 60. The oil pump housing 54 is formed in a shape close to a triangle as viewed from the inside of the crankcase cover 60, and is located in the center of the outer rotor housing that is formed to have an inner diameter substantially the same as the outer diameter of the outer rotor 51. A hole 61 is provided. An oil pump shaft bearing hole 62 for rotatably supporting the oil pump shaft 53 is formed in the bottom 61a of the outer rotor housing hole 61. Further, a bolt hole 54 a for fastening the first lid member 55 and the second lid member 56 with a bolt 80 is formed at a position near the apex of the oil pump housing 54 formed in a substantially triangular shape.

  5, one side of the oil pump shaft 52 is provided with a fitting portion 53b that is fitted into the fitting hole 52b of the inner rotor 52. The cross-sectional shape of the fitting portion 53b is a circular cross section. The part is formed in a cutout shape. The insertion hole 52b of the inner rotor 52 is formed in the same shape as the cross-sectional shape of the insertion portion 53b of the oil pump shaft 52, and when the insertion portion 53b of the oil pump shaft 52 is inserted into the insertion hole 52b of the inner rotor 52. The rotation of the oil pump shaft 52 is transmitted to the inner rotor 52.

  A groove 53a is formed on the other side of the oil pump shaft 52 in the circumferential direction, and a hole 53c through which the retaining pin 57 is inserted is formed perpendicular to the axial direction of the oil pump shaft 53. Has been.

  The first lid member 55 and the second lid member 56 are plate-like members that are formed in substantially the same outer shape as the oil pump housing 54 and cover the oil pump housing 54, and are formed in the bolt holes 54 a of the oil pump housing 54. Insertion holes 55b and 56d for inserting the bolts 80 are formed at corresponding positions. The first lid member 55 is a thick plate-like member, and is formed in a round hole 55a having a diameter substantially the same as the diameter of the oil pump shaft (53) at the approximate center thereof. The second lid member 56 is a plate-like member thinner than the first lid member 55, and a gourd-shaped unique hole 56a is formed such that a part of the large-diameter hole 56b and the small-diameter hole 56c overlap each other. The center point of the small diameter hole 56 c is formed at a position that matches the center of the rotation axis of the oil pump shaft 53.

  The oil pump drive gear 58 has external teeth formed around it. When the oil pump 50 is assembled to the internal combustion engine E, the oil pump drive gear 58 meshes with a driven gear 39 fitted to the crankshaft 32 as shown in FIG. Thus, the rotational driving force of the crankshaft 32 is transmitted to the oil pump 50.

  In the center of the oil pump drive gear 58, a hole 58a for inserting the oil pump shaft is formed. A groove 58b is formed in the hole 58a and the periphery thereof in the diameter direction of the hole 58a. When the oil pump shaft 53 is inserted into the hole 58a of the oil pump drive gear 58, the hole 58c is inserted into the hole 53c of the oil pump shaft 53. A groove 58a is fitted to the stop pin 57 to prevent the oil pump shaft 53 from moving in the direction of the crankcase and to transmit the rotational force of the oil pump drive gear 58 to the oil pump shaft 53. It has become.

  The driven gear 39 that meshes with the oil pump drive gear 58 is spline-fitted to the crankshaft 32 so as to be positioned in the right crankcase cover 60 outside the main bearing 38 that rotatably supports the crankshaft 32. . A disc-shaped centrifugal oil filter 26 is rotatably supported on the crankshaft 32 between the oil pump drive gear 58 and the main bearing 38 adjacent to each other. The oil flowing in the crankshaft 32 passes through the centrifugal oil filter 26, and foreign matters in the oil are removed.

  As shown in FIGS. 3 and 4, an oil inlet 65 and an oil outlet 66 are formed at the bottom 61 a of the outer rotor housing hole 61 formed in the oil pump housing 54. In the right crankcase cover 60, an oil inflow passage 67 is formed downward from the oil inflow port 65, and the oil inflow passage 68 communicates with the oil reservoir 24 from below the oil inflow passage 67 toward the crankcase 20. Is formed. A strainer 25 is disposed above the oil reservoir 24.

  Further, an oil outflow passage 69 is formed in the right crankcase cover 60 from the oil outlet 66 toward the opposite side of the crankcase 20. An oil outflow passage 70 is formed to send lubrication to each part of the supply.

  As shown in FIG. 7, a clutch housing recess 63 that houses the clutch C is formed inside the crankcase cover 60, and a crankshaft bearing hole 64 that receives the crankshaft 32 is further forward than the clutch housing recess 63. It is formed in the position. Further, an oil pump housing 54 is formed in front of the clutch housing recess 63 and below the crankshaft bearing hole 64.

  The oil pump 50 is configured as described above, and is assembled to the internal combustion engine E as follows.

  The retaining pin 57 is inserted into the hole 53 c of the oil pump shaft 53, the oil pump shaft 53 is inserted into the hole 58 a of the oil pump driving gear 58, and the retaining pin 57 is fitted into the groove 58 b of the oil pump driving gear 58. Insert the tip of the oil pump shaft 53 into the large-diameter hole 56b of the specially shaped hole 56a of the second lid member 58, and insert until the groove 53a reaches the position of the unusually shaped hole 56a, and engage the groove 53a and the small-diameter hole 56c. The oil pump shaft 53 is integrally engaged with the second lid member 56. Thereafter, the tip of the oil pump shaft 53 is inserted into the round hole 55 a of the first lid member 55.

  The inner rotor 52 is assembled in the outer rotor 51, and the outer rotor 51 is fitted into the outer rotor storage portion 61 of the oil pump housing 54 formed in the right crankcase cover 60. An insertion portion 53b of the oil pump shaft 53 integrated with the oil pump drive gear 58, the first lid member 55, and the second lid member 56 is inserted into the insertion hole 53b of the inner rotor 52, and then into the oil pump housing 54. The first lid member 55 and the second lid member 56 are fastened together with a bolt 80 and fastened together. The right crankcase cover 60 to which the oil pump 50 is attached is attached to the crankcase 20, and at the same time, the oil pump drive gear 58 that is engaged with the oil pump shaft 54 and rotated together is fitted to the crankshaft 32. The oil pump 50 meshes with the drive gear 39 and is assembled to the internal combustion engine E. When the oil pump 50 is assembled to the internal combustion engine E, the first lid member 55 and a part of the second lid member 56 overlap the centrifugal oil filter 26 and the drive gear 39 in a side view as shown in FIG. ing.

  When the internal combustion engine E is driven, the crankshaft 32 rotates, the oil pump 50 is moved from the crankshaft 32 via the drive gear 39 and the oil pump drive gear 58, and the lubricating oil stored in the oil reservoir 24 Is sucked from the strainer 25, passes through the oil inflow passages 67 and 68, is sucked into the oil pump 50 and pressurized, passes through the oil outflow passages 69 and 70, and is sent to the oil supply portions of the internal combustion engine E.

  Lubricating oil sent to each part of the oil supply by the oil pump 50 is lubricated between the small end of the connecting rod and the piston pin, and is injected toward the piston in the cylinder bore to lubricate the sliding part between the cylinder and the piston. It has come to be used for.

  The lubricating oil sent to each part of the oil supply of the internal combustion engine E and used for lubrication returns to the oil storage part 42 composed of the crankcase 20 and the oil pan 41 and is stored again.

  Since the oil pump 50 of the present embodiment is configured as described above, the second lid member 53 is engaged with the small-diameter hole 56c of the second lid member 56 outside the inner rotor and the groove 53a of the oil pump shaft 53. Since the oil pump shaft 53 is prevented from coming off by being fastened to the oil pump housing 54 with the bolt 80, the oil pump shaft 53 can be easily prevented from coming off, and the rigidity of the inner rotor 52 can be increased. The oil pump 50 can be reduced in size while being secured, and the freedom of design of the internal combustion engine E can be improved by eliminating the restrictions on the arrangement of the oil pump 50 and other parts around the oil pump. Become.

  By receiving the axial force of the oil pump shaft 53 with the thick first lid member 55 and positioning the oil pump shaft 53 in the axial direction by the second lid member 56, the oil pump shaft 53 can be easily arranged in the oil pump housing. 54 can be held.

  With a compact structure, the rotation between the oil pump shaft 53 and the inner rotor 52 and the oil pump shaft 53 can be prevented from coming off, and a small oil pump can be easily and compactly attached.

  Since the oil pump 50 is attached using the dead space in the internal combustion engine E, the internal combustion engine E can be miniaturized and the oil pump 50 can be easily assembled.

  By enlarging the first lid member 55 and the second lid member 56 and widening the gap between the bolts 80, the rotational force of the oil pump 50 can be resisted, and the internal space engine E can be made compact by making effective use of dead space. Can be.

  The oil pump according to the present invention is not limited to the structure of the present embodiment, and various design changes are possible, and the type of the internal combustion engine to be applied is not limited to a multi-cylinder and can be adopted in other types. . Further, the vehicle on which the oil pump according to the present invention is mounted is not limited to a motorcycle but is also effective for a small vehicle such as a buggy vehicle.

  E ... Internal combustion engine, C ... Clutch, 20 ... Crankcase, 26 ... Centrifugal oil filter, 32 ... Crankshaft, 39 ... Drive gear, 50 ... Oil pump, 51 ... Outer rotor, 52 ... Inner rotor, 53 ... Oil pump shaft 54 ... Oil pump housing, 55 ... First lid member, 56 ... Second lid member, 58 ... Oil pump drive gear, 60 ... Right crankcase cover, 63 ... Clutch housing recess, 64 ... Crankshaft bearing hole.

Claims (5)

An outer rotor (51), an inner rotor (52), an oil pump shaft (53) fitted into the inner rotor (52), and an oil pump housing (54) that houses the outer rotor (51) In the pump (50)
The oil pump (50) covers the oil pump housing (54) and has a round hole (55a) having a diameter substantially the same as the diameter of the oil pump shaft (53), and the shaft of the oil pump shaft (53) A thick first lid member (55) for supporting the force;
A second lid member (56) covering the oil pump housing (54) and having a specially shaped hole (56a) formed so that a part of the large diameter hole (56b) and the small diameter hole (56c) overlap each other; ,
The oil pump shaft (53) is formed with a groove portion (53a) that engages with the small diameter hole (56c) of the second lid member (56) in the circumferential direction,
The oil pump shaft (53) is supported by the oil pump housing (54) and the first lid member (55),
The small diameter hole (56c) of the second lid member (56) is engaged with the groove (53a) provided in the oil pump shaft (53),
The oil pump, wherein the first lid member (55) and the second lid member (56) are fastened together with the oil pump housing (54).   The oil pump according to claim 1, wherein the first lid member (55) is formed thicker than the second lid member (56). The inner rotor insertion side of the oil pump shaft (53) has an insertion portion (53b) having a cross-sectional shape in which a part of a circular cross-section is cut out,
At the rotation center of the inner rotor (52), there is an insertion hole (52b) having the same shape as the cross-sectional shape of the insertion portion (53b) of the oil pump shaft (53),
The groove portion (53a) of the oil pump shaft (53) is attached to the small-diameter hole (56c) of the second lid member (56), and is retained and retained.
The oil pump shaft (53) is inserted into the round hole (55a) of the first lid member (55),
The oil pump according to claim 1 or 2, wherein the fitting portion (53b) of the oil pump shaft (53) is fitted into the fitting hole (52b) of the inner rotor (52). The oil pump (50) is used in an internal combustion engine (E) having a crankshaft (32), a crankcase (20), a crankcase cover (60), and a clutch (C).
The internal combustion engine (E) is mounted on a vehicle with the crankshaft (32) oriented in the left-right direction and the cylinder shaft tilted forward.
The oil pump housing (54) is formed integrally with the crankcase cover (60), and the crankcase cover (60) is formed with a clutch housing recess (63) for housing the clutch (C),
A bearing hole (64) for receiving the crankshaft (32) is formed inside the crankcase cover (60), located in front of the clutch housing recess (63),
The oil pump housing (54) is provided in front of the clutch housing recess (63) and below the bearing hole (64),
When the crankcase cover (60) is attached to the crankcase (20), an oil pump drive gear (58) that engages with the oil pump shaft (54) and rotates integrally with the crankshaft (32) The oil pump according to any one of claims 1 to 3, wherein the oil pump is engaged with a drive gear (39) engaged with the oil pump. The internal combustion engine (E) is mounted on a vehicle with the crankshaft (32) oriented in the left-right direction and the cylinder shaft tilted forward, and is mounted on the crankshaft (32). A disc-shaped centrifugal oil filter (27) equipped with,
The centrifugal oil filter (26) is mounted between a main bearing (38) that pivotally supports the crankshaft (32) and the drive gear (39),
The first lid member (55) and the second lid member (56) are fastened to the oil pump housing (54) with a plurality of bolts (80), and at least the first lid member (55) and the second lid member (56) in a side view. The oil according to any one of claims 1 to 4, wherein a part of the second lid member (56) overlaps the centrifugal oil filter (26) or the drive gear (39). pump.

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