JP2016017507A - Oil pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an oil pump capable of reducing tooth hitting sound (noise) between an inner rotor and an outer rotor.SOLUTION: An oil pump 100 of this invention includes an inner rotor 20, and an outer rotor 30 meshed with the inner rotor 20, and the outer rotor 30 includes a first outer rotor part 31 equipped with a first internal tooth 31a, a second outer rotor part 32 equipped with a second internal tooth 32a and coaxially rotatable to the first outer rotor part 31 and arranged to be overlapped in a state of being shifted in an arrow R1 direction, and a torsion spring 35 for energizing the first outer rotor part 31 and the second outer rotor part 32 so that the first internal tooth 31a and the second internal tooth 32a are shifted with each other in the arrow R1 direction. An external tooth 21 of the inner rotor 20 is fastened by the first internal tooth 31a and the second internal tooth 32a in the state that the first outer rotor part 31 and the second outer rotor part 32 are energized by the torsion spring 35.SELECTED DRAWING: Figure 3

Description

  The present invention relates to an oil pump, and more particularly, to an oil pump that includes an inner rotor and an outer rotor having inner teeth that mesh with outer teeth of the inner rotor.

  Conventionally, an oil pump including an inner rotor and an outer rotor having inner teeth that mesh with outer teeth of the inner rotor is known (see, for example, Patent Document 1).

  Patent Document 1 discloses an oil pump device (oil pump) including an inner rotor into which a drive shaft is inserted and an outer rotor having inner teeth that mesh with outer teeth of the inner rotor. In the oil pump device described in Patent Document 1, the outer rotor is divided into four in the axial direction. The four outer rotors are not connected to each other but are simply coaxial and overlapped in the axial direction, and the inner teeth of each outer rotor mesh with the same outer teeth of the inner rotor. The inner rotor is rotationally driven by the drive shaft, so that the four outer rotors are integrally rotated in one direction.

JP 2003-293964 A

  In the oil pump device described in Patent Document 1, since the four outer rotors are integrally rotated in one direction, the inner rotor facing the tooth surface portion on the front side in the rotational direction among the inner teeth of each outer rotor. It is thought that it contacts uniformly with the external tooth surface. Therefore, a gap (backlash) is generated on the rear side in the rotational direction between the inner rotor and the four outer rotors. Here, each of the four outer rotors can freely rotate without being connected to each other. Therefore, when the inner rotor undergoes rotational fluctuations (torque fluctuations), the individual outer rotors move forward and backward in the gaps. There is a possibility of swinging freely. For this reason, there is a problem in that rattling noise (abnormal noise) may occur due to the irregular collision between the outer teeth of the inner rotor and the inner teeth of the outer rotor.

  The present invention has been made to solve the above-described problems, and one object of the present invention is to provide an oil pump capable of reducing rattling noise (abnormal noise) between the inner rotor and the outer rotor. Is to provide.

  In order to achieve the above object, an oil pump according to an aspect of the present invention includes an inner rotor having external teeth and an outer rotor having internal teeth that mesh with external teeth of the inner rotor, and the outer rotor has first internal teeth. A first outer rotor portion, a second outer rotor portion that is coaxially rotatable with respect to the first outer rotor portion and is disposed so as to overlap in a state of being shifted in the rotational direction, and having second internal teeth; and A biasing member that biases the first outer rotor portion and the second outer rotor portion such that the first inner teeth and the second inner teeth of the second outer rotor portion are displaced from each other in the rotational direction. With the first outer rotor portion and the second outer rotor portion biased, the inner teeth of the inner rotor are formed by the first inner teeth of the first outer rotor portion and the second inner teeth of the second outer rotor portion. Are configured to teeth are sandwiched.

  In the oil pump according to one aspect of the present invention, as described above, the outer rotor includes the first outer rotor portion, the second outer rotor portion, the first inner teeth of the first outer rotor portion, and the second inner teeth of the second outer rotor portion. Includes a biasing member that biases the first outer rotor portion and the second outer rotor portion so as to be displaced from each other in the rotational direction. The outer teeth of the inner rotor are sandwiched between the first inner teeth of the first outer rotor portion and the second inner teeth of the second outer rotor portion in a state where the first outer rotor portion and the second outer rotor portion are biased by the biasing member. Configure as follows. Accordingly, the outer rotor is rotated together with the inner rotor in a state where the outer teeth of the inner rotor are sandwiched between the first inner teeth of the first outer rotor portion and the second inner teeth of the second outer rotor portion. That is, at the same time that the outer teeth of the inner rotor push around the first inner teeth of the first outer rotor portion located on the front side in the rotation direction, the second inner teeth of the second outer rotor portion biased by the biasing member are The second outer rotor portion can be rotated by being in contact with the tooth surface portion on the rear side in the rotation direction of the external teeth (opposite to the rotation direction). Further, when the inner rotor is rotated, not only the meshing portion where the outer teeth of the inner rotor are completely sandwiched between the first inner teeth of the first outer rotor portion and the second inner teeth of the second outer rotor portion, but also the other outer portions of the inner rotor. It is possible to increase the number of contact points at which either one of the other first inner teeth of the first outer rotor portion or the other second inner teeth of the second outer rotor portion contacts the teeth. Accordingly, since the inner rotor and the outer rotor can be rotated together in a multipoint contact state, it is possible to reliably suppress the inner rotor and the outer rotor from rattling with each other due to the gap between the outer teeth and the inner teeth. . As a result, the rattling noise (abnormal noise) between the inner rotor and the outer rotor can be reduced.

  In the oil pump according to the first aspect, the first outer rotor portion and the second outer rotor portion are attached such that the first inner teeth of the first outer rotor portion and the second inner teeth of the second outer rotor portion are displaced from each other in the rotational direction. A biasing member for biasing is provided on the outer rotor. Thereby, the intensity of the pulsation of the discharge pressure (periodic fluctuation of the discharge pressure) generated when the oil pump is driven can be reduced. The reason for this will be described below.

  A volume chamber having a pump function is formed between the inner rotor and the outer rotor. Here, in the conventional internal gear type oil pump, oil is sucked when the volume chamber is enlarged during rotational movement. The volume chamber filled with oil is communicated with the discharge port through a closed state without communicating with either the suction port or the discharge port. At this time, an impact force is generated due to instantaneous pressure equalization between the high-pressure discharge port and the low-pressure volume chamber. This phenomenon is caused every time each volume chamber communicates with the discharge port, and appears as a periodic pulsation (pressure fluctuation phenomenon) of the oil discharge pressure.

  On the other hand, in the oil pump of the present invention, the second outer rotor portion is displaced with respect to the first outer rotor portion so as to relieve pressure (impact force) by the urging force of the urging member. That is, the impact force at the time of pressure equalization between the discharge port and the volume chamber is absorbed by the compressive deformation of the urging member (the minute displacement of the second outer rotor portion). Therefore, the intensity of the periodic pulsation of the discharge pressure is reduced. Thus, the present invention is also very useful in that the pulsation of the oil pump can be reduced by using the urging force of the urging member as a secondary means. As described above, the inner rotor and the outer rotor are rotated in a multipoint contact state. However, since the oil pump itself is rotationally driven in a state of being filled with lubricating oil (oil), it is practical with excellent wear resistance. High oil pump can be provided.

  In the oil pump according to the above aspect, the outer rotor preferably has a two-divided structure including a first outer rotor portion and a second outer rotor portion. If comprised in this way, the minimum structure at the time of pinching | interposing the outer tooth of one inner rotor with the 1st internal tooth of a 1st outer rotor part and the 2nd internal tooth of a 2nd outer rotor part by the 2 division structure of an outer rotor easily Can be obtained. With this minimum configuration (two-rotor structure of the outer rotor), an oil pump that can reduce the rattling noise (abnormal noise) between the inner rotor and the outer rotor without complicating the structure of the outer rotor easily. Can be manufactured.

  In the oil pump according to the above aspect, the urging member preferably urges the first outer rotor portion and the second outer rotor portion between the first outer rotor portion and the second outer rotor portion in opposite rotation directions. Is arranged. If comprised in this way, the external tooth of an inner rotor can be easily pinched | interposed by the 1st internal tooth of a 1st outer rotor part, and the 2nd internal tooth of a 2nd outer rotor part. The first outer rotor portion and the second outer rotor portion that overlap each other in the direction in which the rotation axis extends extend such that the first inner teeth and the second inner teeth are shifted in opposite directions at any position on the inner peripheral portion. Combined with. Therefore, the inner rotor and the outer rotor can be stably rotated without rattling in a multipoint contact state.

  In the oil pump according to the above aspect, the crankshaft is preferably inserted into the inner rotor, and is disposed in a gap between the inner rotor and the crankshaft in contact with the inner rotor and the crankshaft and in an elastically deformed state. And a damping member. If comprised in this way, it can prevent that the inner rotor integrated between a crankshaft and an outer rotor originates in the clearance gap between an inner rotor and a crankshaft. Further, the inner rotor can be disposed in a state where the deviation of the rotation center is reduced around the crankshaft by the damping member, and the inner rotor is separated from the first outer rotor portion and the second outer rotor portion by utilizing the spring property of the damping member. The outer rotor can be stably contacted (engaged). Also by this, the rattling noise (abnormal noise) between the inner rotor and the outer rotor can be effectively reduced.

  In this case, preferably, the damping member is disposed so as to surround the outer peripheral surface of the crankshaft in a circumferential manner in a state in contact with the outer peripheral surface of the crankshaft. If comprised in this way, an inner rotor can be stably engage | inserted via the damping member arrange | positioned circumferentially with respect to a crankshaft. Therefore, it is possible to reliably reduce the deviation of the rotation center of the inner rotor from the rotation center of the crankshaft of the internal combustion engine that causes torque fluctuations depending on the rotation angle.

  In addition, in this application, the following structures are also considered in the oil pump by the said one situation.

(Additional item 1)
That is, in the oil pump according to the first aspect, the inner rotor has a thickness larger than the thickness of the first outer rotor portion and the thickness of the second outer rotor portion in the direction in which the rotation axis extends.

(Appendix 2)
In the oil pump according to the first aspect, each of the first outer rotor portion and the second outer rotor portion has a first concave portion and a second concave portion formed on opposing surfaces that overlap each other in the direction in which the rotation axis extends. The first end of the biasing member is engaged with the first recess and the second end opposite to the first end is engaged with the second recess, so that the first outer rotor portion and the second end are engaged. The outer rotor portion is configured to be biased.

  ADVANTAGE OF THE INVENTION According to this invention, the oil pump which can reduce the rattling noise (abnormal noise) between an inner rotor and an outer rotor as mentioned above can be provided.

1 is a perspective view schematically showing an engine equipped with an oil pump according to a first embodiment of the present invention. It is the disassembled perspective view which showed the structure of the periphery of the oil pump by 1st Embodiment of this invention. It is sectional drawing which showed the internal structure of the oil pump by 1st Embodiment of this invention. It is sectional drawing which showed the state before an outer rotor was assembled in the oil pump by 1st Embodiment of this invention. It is sectional drawing which showed the state by which the outer rotor was assembled in the oil pump by 1st Embodiment of this invention. It is sectional drawing which showed the state by which the crankshaft was inserted in the inner rotor in the oil pump by 1st Embodiment of this invention. It is sectional drawing which showed the structure by the side of the outer rotor in the oil pump by the 1st modification of 1st Embodiment of this invention. It is sectional drawing which showed the structure by the side of the outer rotor in the oil pump by the 2nd modification of 1st Embodiment of this invention. It is sectional drawing which showed the internal structure of the oil pump by 2nd Embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
First, with reference to FIGS. 1-6, the structure of the oil pump 100 by 1st Embodiment of this invention is demonstrated. In the following description, it is assumed that the crankshaft 93 extends along the X axis and the piston 92 reciprocates along the Z axis when the engine 90 is used as a reference.

  The oil pump 100 according to the first embodiment of the present invention is mounted on an automobile (not shown) provided with an engine 90 as shown in FIG. The oil pump 100 has a function of pumping up oil (lubricating oil) 1 in the oil pan 91 and supplying (pumping) the oil around the piston 92 and movable parts (sliding parts) such as the crankshaft 93.

  As shown in FIG. 2, the internal gear type oil pump 100 includes an aluminum alloy casing portion 10, an inner rotor 20 and an outer rotor 30 that are rotatably provided in the casing portion 10, and a casing portion 10 that is connected to an engine 90. An aluminum alloy pump cover 40 that is sealed from the inside (crank chamber side) and an annular oil seal 50 that is fitted into the opening 10b on the X2 side of the casing portion 10 are provided. The casing portion 10 is integrally provided at the lower portion of the chain cover 10a that covers the side end surface of the engine 90 on the X2 side. A crankshaft 93 is inserted into the rotation center A (X axis) of the inner rotor 20, and the driving force of the engine 90 (see FIG. 1) is directly transmitted to the inner rotor 20.

  Here, as shown in FIG. 3, the rotation center A of the inner rotor 20 (the axis of the crankshaft 93) is eccentric by a certain amount in the direction of the arrow Z <b> 2 with respect to the rotation center B of the outer rotor 30. When the crankshaft 93 and the inner rotor 20 are rotated in the arrow R1 direction (clockwise direction), the outer rotor 30 is rotated in the same direction with a slight delay. At the time of rotation, in a place where the distance between the inner rotor 20 and the outer rotor 30 is short (Z2 side region), the outer teeth 21 of the inner rotor 20 and the inner teeth of the outer rotor 30 (first inner teeth 31a and second inner teeth 32a described later). Mesh with each other. On the other hand, since there is only one outer tooth 21 of the inner rotor 20 in the far side (Z1 side region), a gap (volume chamber U) is gradually formed between the outer rotor 30 and the outer rotor 21. Further, the volume chamber U expands or contracts with the rotational movement in the direction of the arrow R1, and a pump function is created. Therefore, the oil 1 (see FIG. 1) is sucked into the volume chamber U in accordance with the volume change (enlargement) from the minimum value to the maximum value of the volume chamber U, and the volume change (reduction) from the maximum value of the volume chamber U to the minimum value. ), The oil 1 held in the volume chamber U is discharged from the volume chamber U to the outside.

  The outer teeth 21 of the inner rotor 20 have a tooth profile such that the tooth width is narrowed and the tooth height is extended radially outward compared to the outer teeth of the inner rotor in a general trochoid pump. Yes. Further, the inner teeth (the first inner teeth 31 a and the second inner teeth 32 a) of the outer rotor 30 are formed so as to be able to mesh with each other according to the tooth shape of the outer teeth 21. Thereby, the volume of the volume chamber U formed in the oil pump 100 is comprised so that more can be ensured. Therefore, when the same oil discharge amount is required for the engine 90 (see FIG. 1), the diameter (rotor width) and thickness (X-axis direction) of the inner rotor 20 and the outer rotor 30 can be reduced. Therefore, the oil pump 100 is downsized in this respect.

  As shown in FIGS. 1 and 2, the oil pump 100 is provided with a suction oil passage 11 for sucking the oil 1 and a discharge oil passage 12 for discharging the oil 1. The suction oil passage 11 and the discharge oil passage 12 are formed with concave shapes on the inner surfaces of the casing portion 10 and the pump cover 40 (opposing surfaces on the side where the inner rotor 20 and the outer rotor 30 are rotatably sandwiched). Further, the suction oil passage 11 and the discharge oil passage 12 are each formed with a predetermined flow path shape in a state where the pump cover 40 is attached to the casing portion 10. 3, the suction port 11a at the front end region of the suction oil passage 11 and the discharge port 12a at the front end region of the discharge oil passage 12 are respectively in meshing regions of the inner rotor 20 and the outer rotor 30, as indicated by a two-dot chain line in FIG. Has been placed.

  Therefore, the oil pump 100 sucks the oil 1 from the oil pan 91 (see FIG. 1) into the volume chamber U via the suction port 11a, and then discharges the oil port 100 in a state where a predetermined hydraulic pressure is generated as the volume chamber U is reduced. It has a function of discharging from 12a. As shown in FIG. 1, the oil 1 is pumped toward the oil filter 94 via the discharge path 2. Oil 1 from which foreign matter has been removed by passing through the oil filter 94 is supplied to a movable part (sliding part) in the engine 90. Further, the oil 1 supplied into the engine 90 is returned to the oil pan 91 through the return oil passage 3.

  Here, in the first embodiment, as shown in FIG. 4, the outer rotor 30 includes a first outer rotor portion 31 on the one side (X2 side) having the first inner teeth 31a and the other side having the second inner teeth 32a. It has a two-divided structure including the second outer rotor portion 32 on the (X1 side). The external teeth 21 are 13 pieces, and the first internal teeth 31a and the second internal teeth 32a are both 14 pieces. In FIG. 3, the first outer rotor portion 31 indicated by the solid line is disposed on the front side of the paper, and the second outer rotor portion 32 indicated by the broken line is disposed on the back side of the paper. Further, in the innermost part of the drawing, the positions of the suction port 11a and the discharge port 12a are indicated by a two-dot chain line. As shown in FIGS. 4 and 5, a coiled torsion spring 35 is incorporated between the first outer rotor portion 31 and the second outer rotor portion 32. The torsion spring 35 is an example of the “biasing member” in the present invention.

  The torsion spring 35 is made of metal. Further, as shown in FIG. 4, the torsion spring 35 has one end 35a bent radially inwardly inserted into a spring engaging portion 31b provided in the first outer rotor portion 31, and the other end 35b similarly. The second outer rotor portion 32 is inserted into and connected to a spring engaging portion 32b provided inside. Further, in this state, the first outer rotor portion 31 and the second outer rotor portion 32 are coaxially overlapped with each other along the X-axis direction, whereby the outer rotor 30 as shown in FIG. 5 is assembled. In the state where the first outer rotor portion 31 and the second outer rotor portion 32 are connected via the torsion spring 35 in the natural state, as shown in FIG. 5, the second inner teeth 32 a are in relation to the first inner teeth 31 a. It is stationary with a slight shift in the direction of arrow R1 around the rotation center A.

  Further, the torsion spring 35 has a role of urging the first outer rotor portion 31 and the second outer rotor portion 32 in opposite rotation directions. Specifically, as shown in FIG. 3, in a state where the outer rotor 30 is engaged with the inner rotor 20, the second outer rotor portion 32 is applied to the first inner teeth 31 a of the first outer rotor portion 31 by the biasing force of the torsion spring 35. The second internal teeth 32a are slightly shifted in the direction of the arrow R1 around the rotation center A. That is, the outer rotor 30 is configured so that the assembly operator meshes with the outer teeth 21 of the inner rotor 20 in a state where the first inner teeth 31a and the second inner teeth 32a are substantially overlapped against the urging force of the torsion spring 35. Are incorporated into the casing portion 10. After being sealed by the pump cover 40, the outer rotor 30 has the second inner teeth 32a of the second outer rotor portion 32 as shown by the arrow R1 with respect to the first inner teeth 31a of the first outer rotor portion 31 again by the biasing force of the torsion spring 35. Slightly shifted in the direction.

  As a result, in the oil pump 100, the first inner teeth 31a of the first outer rotor portion 31 and the first outer teeth 31a and the second outer rotor portion 32 are biased in the direction of the arrow R1 by the torsion spring 35 with respect to the first outer rotor portion 31. The outer teeth 21 of the inner rotor 20 are sandwiched between the second inner teeth 32 a of the two outer rotor portions 32. That is, when the oil pump 100 is in operation, the portion of the inner rotor 20 and the outer rotor 30 that engage with each other at the shortest distance (the lowest portion on the Z2 side) is the front of the outer teeth 21 of the inner rotor 20 in the rotational direction (arrow R1 direction). The tooth surface portion 21a located on the side contacts (presses) the first inner teeth 31a of the first outer rotor portion 31 in the direction of the arrow R1 at the position P1. At the same time, the tooth surface portion 21b of the outer teeth 21 of the inner rotor 20 located on the rear side in the rotational direction (arrow R2 direction side) is moved by the biasing force of the torsion spring 35 at the position Q1. It is pressed in the direction of arrow R1 from the second internal tooth 32a side.

  Therefore, the outer rotor 30 has the inner rotor 20 in a state where the outer teeth 21 of the inner rotor 20 are sandwiched between the first inner teeth 31a of the first outer rotor portion 31 and the second inner teeth 32a of the second outer rotor portion 32 at the positions P1 and Q1. In addition, it is configured to rotate in the direction of arrow R1. At the position P <b> 1, the first inner teeth 31 a of the first outer rotor portion 31 are pushed around by the tooth surface portion 21 a of the inner rotor 20. Further, at the position Q1, the second inner teeth 32a of the second outer rotor portion 32 are rotated while contacting (pressing) the tooth surface portion 21b of the inner rotor 20 by the urging force of the torsion spring 35. Accordingly, when viewed only from the relationship between the inner rotor 20 and the first outer rotor portion 31, the gap that exists on the tooth surface portion 21 b side is the second inner teeth 32 a of the second outer rotor portion 32 behind the tooth surface portion of the inner rotor 20. It is partially eliminated by contacting 21b. As a result, the outer teeth 21 of the inner rotor 20 are supported (engaged) on the outer rotor 30 side without being rattled at the positions P1 and Q1. This state is maintained not only when the oil pump 100 is operating but also when it is not operating.

  Since the oil pump 100 is formed with a tooth profile for the purpose of further increasing the oil discharge amount, the number of contact points between the external teeth 21 and the first internal teeth 31a (second internal teeth 32a) is originally small. Therefore, in the first embodiment, as shown in FIG. 3, when the inner rotor 20 is rotated, the outer teeth 21 of the inner rotor 20 are moved to the first inner teeth 31 a of the first outer rotor portion 31 and the second teeth of the second outer rotor portion 32. The other first inner teeth 31a or the second outer rotor of the first outer rotor portion 31 with respect to the other outer teeth 21 of the inner rotor 20 as well as the meshing portions (position P1 and position Q1) completely sandwiched by the inner teeth 32a. The number of contact points at which any one of the other second internal teeth 32a of the part 32 contacts is increased.

  For example, the inner rotor 20 contacts (presses) the first inner teeth 31a of the first outer rotor portion 31 at the positions P2 to P4. The inner rotor 20 is rotated along with the second outer rotor portion 32 in a state where the second inner teeth 32a of the second outer rotor portion 32 are in contact with each other at the positions Q2 to Q4. In this case, the number of contact points between the inner rotor 20 and the first outer rotor portion 31 (a total of four positions P1 to P4) and the number of contact points between the inner rotor 20 and the second outer rotor portion 32 (a total of four positions Q1 to Q4) Are equal. As described above, the inner rotor 20 and the outer rotor 30 that originally have a small number of contact points between the external teeth and the internal teeth are in a multipoint contact state (total of 8 locations) by shifting the first internal teeth 31a and the second internal teeth 32a from each other. ) To rotate. This further suppresses the inner rotor 20 and the outer rotor 30 from rattling in the circumferential direction due to the gap between the outer teeth 21 and the inner teeth (the first inner teeth 31a and the second inner teeth 32a). . Although the inner rotor 20 and the outer rotor 30 are rotated in a multipoint contact state, the oil pump 100 itself is rotationally driven in a state filled with the lubricating oil (oil 1), so that the wear resistance at the contact point is excellent. ing.

  It is to be noted that the provision of the torsion spring 35 allows the first inner teeth 31a of the first outer rotor portion 31 and the second inner teeth 32a of the second outer rotor portion 32 to be shifted from each other in the rotational direction. Bring.

  First, in the conventional general internal gear type oil pump, oil is sucked from the suction port into the expanding volume chamber that rotates and moves in the direction of arrow R1. There is an instantaneous state in which the volume chamber is not in communication with either the suction port or the discharge port (in FIG. 3, the volume chamber U is located at the uppermost portion on the Z1 side). After that, the moment when the volume chamber rotates and moves in the direction of the arrow R1 and communicates with the discharge port, the internal volume of the volume chamber is added to the internal volume on the discharge port side, and the high oil pressure on the discharge port side instantaneously increases. (Volume chamber increases internal pressure momentarily). Also, the impact force at the time of pressure drop is transmitted to the discharge port side. Each time a plurality of volume chambers are repeatedly communicated with the discharge port, an instantaneous hydraulic pressure drop occurs, and this impact force appears as a periodic pulsation (pressure fluctuation phenomenon) of the discharge pressure. Conventional internal gear type oil pumps potentially have such characteristics.

  On the other hand, in the oil pump 100 of the first embodiment, the outer rotor 30 is divided into two parts, a first outer rotor part 31 and a second outer rotor part 32. And the 1st outer rotor part 31 and the 2nd outer rotor part 32 are connected by the torsion spring 35, Therefore The 2nd outer rotor part 32 can carry out forward / reverse with respect to the 1st outer rotor part 31 with the urging | biasing force of the torsion spring 35 ( It is displaced in the direction of arrow R1 and arrow R2. Therefore, as shown in FIG. 3, when the volume chamber U that has passed through the uppermost portion on the Z1 side is communicated with the discharge port 12a, the high hydraulic pressure on the discharge port 12a side causes the second inner teeth 32a of the second outer rotor portion 32 to be high. Act on. At this time, the increase in the internal pressure of the volume chamber U is slightly displaced so that the second outer rotor portion 32 relaxes the pressure (impact force) in the direction of the arrow R2 (the direction against the urging force of the torsion spring 35). Is absorbed by That is, the impact force accompanying the increase in pressure in the volume chamber U is absorbed by the compression deformation of the torsion spring 35. Therefore, in the oil pump 100, the intensity of the pulsation of the discharge pressure is reduced. Thus, by incorporating the torsion spring 35 into the outer rotor 30, the pulsation of the oil pump 100 is relieved by using the biasing force of the torsion spring 35 as a secondary. The torsion spring 35 generates an urging force again after momentary compressive deformation. Therefore, the second inner teeth 32a of the second outer rotor portion 32 are returned again to positions shifted in the arrow R1 direction from the first inner teeth 31a. Thereby, in the meshing part of the external teeth 21 and the internal teeth (the first internal teeth 31a and the second internal teeth 32a), the external teeth 21 are sandwiched between the first internal teeth 31a and the second internal teeth 32a. Repeated immediately.

  The biasing force of the torsion spring 35 is such that when the outer rotor 30 is combined with the inner rotor 20 and the first outer rotor portion 31 is used as a reference, the second outer rotor portion 32 (second inner teeth 32a) is the inner rotor 20. Any size that can be pressed to such an extent that the outer teeth 21 do not rattle can be used. Further, the biasing force of the torsion spring 35 compresses itself when a high oil pressure on the discharge port 12a side acts on the volume chamber U in order to reduce the pulsation intensity (impact force) of the oil pump 100. It is sufficient that the second outer rotor portion 32 be of a size that can be pushed back instantaneously. The torsion spring 35 is preferably adjusted to an urging force that is not too hard and not too soft within such a range.

  As shown in FIGS. 3 and 6, a crankshaft 93 is inserted into the rotation center A of the inner rotor 20. More specifically, the crankshaft 93 has a cross section 93s (see FIG. 3) in which D-cut processing is performed on both surfaces (Y1 side and Y2 side) of the round shaft. Further, the inner rotor 20 has a shaft insertion hole 22 (see FIG. 3) having an opening cross-sectional shape that is slightly larger than the cross-section 93s of the crankshaft 93. Further, when the crankshaft 93 is inserted into the shaft insertion hole 22 of the inner rotor 20 and penetrated, a predetermined gap (clearance) S is generated between the inner rotor 20 and the crankshaft 93. A concave portion 22a extending along the X-axis direction is formed on the inner side surface of the shaft insertion hole 22. The recess 22a is formed at a position facing the pair of D-cut surfaces 93b of the crankshaft 93 in order to make it easy to return the oil 1 leaked from the volume chamber U to the oil pan 91 through the gap S. . Further, the crankshaft 93 has a shaft end portion 93c (see FIG. 2) having an outer diameter between the D cut surfaces 93b at the end portion on the X2 side. The shaft end portion 93c having a circular cross section is slidably inserted into an oil seal 50 (see FIG. 2) fitted in the opening portion 10b on the X2 side of the casing portion 10.

  Here, in the first embodiment, as shown in FIG. 6, an O-ring (O-ring) 36 having springiness (elasticity) is disposed in the gap S between the inner rotor 20 and the crankshaft 93. The O-ring 36 having an annular shape is made of a rubber or resin material having excellent oil resistance, heat resistance, cold resistance and wear resistance, and is disposed in a state of being elastically deformed while being in contact with the inner rotor 20 and the crankshaft 93. ing. In this case, as shown in FIG. 3, the O-ring 36 is disposed so as to surround the outer peripheral surface 93 a of the crankshaft 93 in a state of being in contact with the outer peripheral surface 93 a of the crankshaft 93. Further, as shown in FIG. 6, the O-ring 36 is fitted in a circumferential and concave accommodating portion 22 b provided in the central portion of the shaft insertion hole 22 along the X-axis direction. In FIG. 6, the mounting position of the pump cover 40 is indicated by a two-dot chain line, and the casing portion 10 and the outer rotor 30 (see FIG. 2) are not shown for convenience of explanation. The O-ring 36 is an example of the “damping member” in the present invention.

  Thus, the O-ring 36 prevents the inner rotor 20 incorporated between the crankshaft 93 and the outer rotor 30 from rattling due to the clearance S between the inner rotor 20 and the crankshaft 93. Further, the inner rotor 20 can be driven to rotate in a state where the fluctuation of the rotation center A around the crankshaft 93 is reduced by the O-ring 36, and the inner rotor 20 can be driven by utilizing the spring property (elasticity) of the O-ring 36. The outer rotor 30 including the first outer rotor portion 31 and the second outer rotor portion 32 is configured to stably contact (mesh). Therefore, in this respect as well, the O-ring 36 contributes to reduction of rattling noise (abnormal noise) between the inner rotor 20 and the outer rotor 30.

  As described above, in the oil pump 100, the inner rotor 20 is fitted so as to reduce rattling with respect to the crankshaft 93, and the outer rotor 30 is driven to rotate stably with respect to the crankshaft 93. The outer teeth 21 are sandwiched between the inner rotor 20 and the inner rotor 20. The oil pump 100 in the first embodiment is configured as described above.

  In the first embodiment, the following effects can be obtained.

  That is, in the first embodiment, as described above, the outer rotor 30 includes the first outer rotor portion 31, the second outer rotor portion 32, the first inner teeth 31 a of the first outer rotor portion 31, and the second outer rotor portion 32. A torsion spring 35 that urges the first outer rotor portion 31 and the second outer rotor portion 32 so as to be displaced from each other in the arrow R1 direction with respect to the inner teeth 32a is included. Then, with the first outer rotor portion 31 and the second outer rotor portion 32 being urged by the torsion spring 35, the first inner teeth 31a of the first outer rotor portion 31 and the second inner teeth 32a of the second outer rotor portion 32 are used. The outer teeth 21 of the inner rotor 20 are sandwiched. As a result, the outer rotor 30 rotates together with the inner rotor 20 with the outer teeth 21 of the inner rotor 20 being sandwiched between the first inner teeth 31a of the first outer rotor portion 31 and the second inner teeth 32a of the second outer rotor portion 32. That is, at the position P1 (see FIG. 3), the tooth surface portion 21a of the outer teeth 21 of the inner rotor 20 pushes the first inner teeth 31a of the first outer rotor portion 31 located on the front side in the direction of the arrow R1, and simultaneously twists. The second inner teeth 32a of the second outer rotor portion 32 biased by the spring 35 are tooth surfaces 21b on the rear side (arrow R2 direction side) in the rotational direction of the outer teeth 21 of the inner rotor 20 at the position Q1 (see FIG. 3). Is pressed (contacted), and the second outer rotor portion 32 can be rotated (rotated). Further, when the inner rotor 20 is rotated, a meshing portion (Z2) in which the outer teeth 21 of the inner rotor 20 are completely sandwiched between the first inner teeth 31a of the first outer rotor portion 31 and the second inner teeth 32a of the second outer rotor portion 32. Any one of the other first internal teeth 31a of the first outer rotor portion 31 or the other second internal teeth 32a of the second outer rotor portion 32 with respect to the other external teeth 21 of the inner rotor 20 It is possible to increase the number of contact points (position P2 to position P4 and position Q2 to position Q4) with which one side contacts. Accordingly, since the inner rotor 20 and the outer rotor 30 can be rotated together in a multipoint contact state, the clearance between the outer teeth 21 and the inner teeth (the first inner teeth 31a and the second inner teeth 32a) is caused. It is possible to reliably prevent the inner rotor 20 and the outer rotor 30 from rattling with each other. As a result, rattling noise (abnormal noise) between the inner rotor 20 and the outer rotor 30 can be reduced.

  In the first embodiment, the first outer rotor portion 31 and the second outer rotor are arranged such that the second inner teeth 32a of the second outer rotor portion 32 are displaced in the arrow R1 direction with respect to the first inner teeth 31a of the first outer rotor portion 31. A torsion spring 35 that biases the portion 32 is provided in the outer rotor 30. Thereby, the intensity of the pulsation of discharge pressure (periodic fluctuation of discharge pressure) generated when the oil pump 100 is driven can be reduced. That is, the second outer rotor portion 32 is displaced with respect to the first outer rotor portion 31 by the urging force of the torsion spring 35 so as to relieve the pressure (impact force). Therefore, the impact force at the time of pressure equalization between the discharge port 12a and the volume chamber U is absorbed by the compression deformation of the torsion spring 35 (the minute displacement of the second outer rotor portion). Therefore, the intensity of the periodic pulsation of the discharge pressure can be reduced. Thus, it is very useful in that the pulsation intensity of the oil pump 100 can be relieved by using the biasing force of the torsion spring 35 as a secondary. Although the inner rotor 20 and the outer rotor 30 are rotated in a multipoint contact state, the oil pump 100 itself is rotationally driven in a state where it is filled with the lubricating oil (oil 1). A high oil pump 100 can be provided.

  In the first embodiment, the outer rotor 30 has a two-divided structure including a first outer rotor portion 31 and a second outer rotor portion 32. Thereby, the minimum structure when the outer teeth 21 of one inner rotor 20 are sandwiched between the first inner teeth 31a of the first outer rotor portion 31 and the second inner teeth 32a of the second outer rotor portion 32 by the two-divided structure of the outer rotor 30. Can be easily obtained. The minimum configuration (a two-part structure of the outer rotor 30) enables oil to be reduced (abnormal noise) between the inner rotor 20 and the outer rotor 30 without excessively complicating the structure of the outer rotor 30. The pump 100 can be easily manufactured.

  In the first embodiment, between the first outer rotor portion 31 and the second outer rotor portion 32, the first outer rotor portion 31 and the second outer rotor portion 32 are rotated in opposite directions (arrow R1 direction and arrow R2 direction). The torsion spring 35 is disposed so as to be biased. Thereby, the outer teeth 21 of the inner rotor 20 can be easily sandwiched between the first inner teeth 31 a of the first outer rotor portion 31 and the second inner teeth 32 a of the second outer rotor portion 32. The first outer rotor portion 31 and the second outer rotor portion 32 that overlap each other in the direction in which the rotation axis (X axis) extends are such that the first inner teeth 31a and the second inner teeth 32a are located at any position on the inner peripheral portion 30a. They are combined with the inner rotor 20 so as to be displaced in opposite directions. Therefore, the inner rotor 20 and the outer rotor 30 can be stably rotated without rattling in a multipoint contact state.

  In the first embodiment, an O-ring 36 having spring properties is disposed in the gap S between the inner rotor 20 and the crankshaft 93. Further, the O-ring 36 is configured to be in contact with the inner rotor 20 and the crankshaft 93 and to be elastically deformed. Thereby, it is possible to prevent the inner rotor 20 incorporated between the crankshaft 93 and the outer rotor 30 from rattling due to the gap S between the inner rotor 20 and the crankshaft 93. Further, the inner rotor 20 can be disposed in a state where the rotational center shift is reduced around the crankshaft 93 by the O-ring 36, and the inner rotor 20 is made to be the first outer rotor portion 31 by utilizing the spring property of the O-ring 36. In addition, the outer rotor 30 including the second outer rotor portion 32 can be stably contacted (engaged). Also by this, the rattling noise (abnormal noise) between the inner rotor 20 and the outer rotor 30 can be effectively reduced.

  In the first embodiment, the annular O-ring 36 is disposed so as to surround the outer peripheral surface 93a of the crankshaft 93 in a state of being in contact with the outer peripheral surface 93a of the crankshaft 93. Thereby, the inner rotor 20 can be stably fitted through the O-ring 36 arranged circumferentially with respect to the crankshaft 93. Accordingly, it is possible to reliably reduce the deviation of the rotation center A of the inner rotor 20 from the rotation center of the crankshaft 93 of the engine 90 that causes torque fluctuation depending on the rotation angle.

(First modification of the first embodiment)
Next, a first modification of the first embodiment of the present invention will be described with reference to FIGS. In the first modification of the first embodiment, an example in which the outer rotor 50 is configured by incorporating a coil spring 55 between the first outer rotor portion 51 and the second outer rotor portion 52 will be described. The coil spring 55 is an example of the “biasing member” in the present invention. In the drawing, the same reference numerals as those in the first embodiment are attached to the same components as those in the first embodiment.

  As shown in FIG. 7, the oil pump in the first modification of the first embodiment includes an inner rotor 20 (see FIG. 2) and an outer rotor 50. Here, the outer rotor 50 is divided into two parts: a first outer rotor part 51 having first internal teeth 51a and a second outer rotor part 52 having second internal teeth 52a. The outer surface 51 b of the first outer rotor portion 51 is formed with a recess 51 c, and the outer surface 52 b of the second outer rotor portion 52 is formed with a recess 52 c. Moreover, the one recessed part 53 of rectangular shape is formed by making the recessed part 51c and the recessed part 52c mutually oppose. In addition, the recessed part 53 has the depth of the grade which does not reach the tooth bottom part of the 1st internal tooth 51a and the 2nd internal tooth 52a.

  A coil spring 55 is configured to be incorporated in the recess 53 in a state where the first outer rotor portion 51 and the second outer rotor portion 52 are superposed coaxially with each other along the X-axis direction. Here, the coil spring 55 is a metal compression coil spring, and the assembly operator almost superimposes the first internal teeth 51a and the second internal teeth 52a against the urging force (extension force) of the coil spring 55. In this state, it is incorporated into the casing portion 10 (see FIG. 2) so as to mesh with the external teeth 21 (see FIG. 2) of the inner rotor 20. Therefore, after being sealed by the pump cover 40 (see FIG. 2), the outer rotor 50 is again subjected to the second outer rotor with respect to the first inner teeth 51a of the first outer rotor portion 51 by the urging force (extension force) of the coil spring 55. The second internal teeth 52a of the portion 52 are slightly shifted in the direction of the arrow R1.

  Thus, by fitting the coil spring 55 into the recess 53, the first inner teeth 51a and the second inner teeth 51a are in a state where the second outer rotor portion 52 is urged in the direction of the arrow R1 with respect to the first outer rotor portion 51. The external teeth 21 of the inner rotor 20 are sandwiched between the teeth 52a. In this oil pump, a structure in which one coil spring 55 is fitted in the recess 53 is provided in two places in total. Although only one location is shown in FIG. 7, the same configuration is provided at two locations (at intervals of 180 degrees) around the outer periphery of the outer rotor 50. Note that the structure around the inner rotor 20 including the O-ring 36 (see FIG. 2) is the same as that of the oil pump 100 (see FIG. 2).

  In the first modification of the first embodiment, the outer rotor 50 is configured by incorporating the coil spring 55 between the first outer rotor portion 51 and the second outer rotor portion 52 as described above. Thus, even if the coil spring 55 is used, the inner rotor 20 and the outer rotor 50 can be rotated together in a multipoint contact state, so the external teeth 21 and the internal teeth (the first internal teeth 51a and the second internal teeth 52a). ), The inner rotor 20 and the outer rotor 50 can be reliably prevented from rattling with each other. As a result, the rattling noise (abnormal noise) between the inner rotor 20 and the outer rotor 50 can be reduced. The remaining effects of the first modification of the first embodiment are similar to those of the aforementioned first embodiment.

(Second modification of the first embodiment)
Next, with reference to FIG. 2 and FIG. 8, the 2nd modification of 1st Embodiment of this invention is demonstrated. In the second modification of the first embodiment, an example in which the outer rotor 70 is configured by incorporating a leaf spring 75 between the first outer rotor portion 71 and the second outer rotor portion 72 will be described. The leaf spring 75 is an example of the “biasing member” in the present invention. In the drawing, the same reference numerals as those in the first embodiment are attached to the same components as those in the first embodiment.

  As shown in FIG. 8, the oil pump in the second modification of the first embodiment includes an inner rotor 20 (see FIG. 2) and an outer rotor 70. Here, the outer rotor 70 is divided into two parts, a first outer rotor portion 71 having first internal teeth 71a and a second outer rotor portion 72 having second internal teeth 72a. A recess 71 c is formed on the outer surface 71 b of the first outer rotor portion 71, and a recess 72 c is formed on the outer surface 72 b of the second outer rotor portion 72. The recess 72c is larger than the recess 71c. The recesses 71c and 72c have a depth that does not reach the bottom of the first internal teeth 71a and the second internal teeth 72a.

  And it is comprised so that the metal leaf | plate spring 75 may be inserted in the state which made the recessed part 71c and the recessed part 72c oppose each other as FIG. 8 shows. In this case, the other end 75b of the leaf spring 75 is disposed in the recess 72c in a state where the one end 75a of the leaf spring 75 is inserted and fixed in the recess 71c without a gap. Then, the outer teeth 21 of the inner rotor 20 (see FIG. 2) with the assembly operator substantially overlapping the first inner teeth 71a and the second inner teeth 72a against the urging force (in the direction of arrow R1) of the leaf spring 75. ) And the casing portion 10 (see FIG. 2). Therefore, after being sealed by the pump cover 40 (see FIG. 2), the outer rotor 70 is again moved to the second outer rotor with respect to the first inner teeth 71 a of the first outer rotor portion 71 by the urging force (restoring force) of the leaf spring 75. The second internal teeth 72a of the portion 72 are slightly shifted in the arrow R1 direction.

  Thus, by fitting the leaf spring 75 into the recess 71c and the recess 72c, the second inner rotor 71 is biased in the direction of the arrow R1 with respect to the first outer rotor 71, and the first inner teeth 71a The outer teeth 21 (see FIG. 2) of the inner rotor 20 are sandwiched between the second inner teeth 72a. In this oil pump, although one leaf spring 75 is fitted in a pair of the recess 71c and the recess 72c, only two places are illustrated in FIG. Four places are provided around the outer periphery of the. The structure around the inner rotor 20 including the O-ring 36 (see FIG. 2) is the same as that of the oil pump 100 (see FIG. 2).

  In the second modification of the first embodiment, the outer rotor 70 is configured by incorporating the leaf spring 75 between the first outer rotor portion 71 and the second outer rotor portion 72 as described above. Thus, even if the leaf spring 75 is used, the inner rotor 20 and the outer rotor 70 can be rotated together in a multipoint contact state, so the external teeth 21 and the internal teeth (the first internal teeth 71a and the second internal teeth 72a). ), The inner rotor 20 and the outer rotor 70 can be reliably prevented from rattling with each other. As a result, rattling noise (abnormal noise) between the inner rotor 20 and the outer rotor 70 can be reduced. The remaining effects of the second modification of the first embodiment are similar to those of the aforementioned first embodiment.

(Second Embodiment)
Next, a second embodiment will be described with reference to FIG. 1, FIG. 3, FIG. 4, and FIG. In the second embodiment, unlike the first embodiment, an example in which the present invention is applied to a general trochoid oil pump 200 will be described. In the figure, components similar to those in the first embodiment are denoted by the same reference numerals as those in the first embodiment.

  In the oil pump 200 according to the second embodiment of the present invention, as shown in FIG. 9, an inner rotor 220 and an outer rotor 230 are incorporated in the casing portion 10 (see FIG. 1). Here, the inner rotor 220 has external teeth 221. Also in the second embodiment, the outer rotor 230 includes the first outer rotor portion 231 on the one side (X2 side) having the first inner teeth 231a and the second on the other side (X1 side) having the second inner teeth 232a. The outer rotor portion 232 has a two-part structure. The external teeth 221 are 11 pieces, and the first internal teeth 231a and the second internal teeth 232a are both 10 pieces.

  Here, in the second embodiment, the external teeth 221 and the first internal teeth 231a (second internal teeth 232a) have tooth shapes formed by trochoidal curves. Also in such a trochoidal oil pump 200, the outer rotor 230 has a two-part structure, and the torsion spring 35 (see FIG. 4) is incorporated between the first outer rotor portion 231 and the second outer rotor portion 231 so that the outer rotor 230 is assembled. It is composed.

  As a result, the first inner teeth 231a of the first outer rotor portion 231 and the first inner teeth 231a in the state where the second outer rotor portion 232 is urged in the direction of the arrow R1 with respect to the first outer rotor portion 231 by the torsion spring 35 (see FIG. 4). The outer teeth 221 of the inner rotor 220 are configured to be securely sandwiched by the second inner teeth 232a of the two outer rotor portion 232. That is, when viewed only from the relationship between the inner rotor 220 and the first outer rotor portion 231, the gap that exists on the tooth surface portion 221 b side is the second inner teeth 232 a of the second outer rotor portion 232 behind the tooth surface portion of the inner rotor 220. It is partially eliminated by contacting 221b. Accordingly, the outer teeth 221 of the inner rotor 220 are supported (engaged) on the outer rotor 230 side without being rattled at the positions P1 and Q1.

  In FIG. 9, the second outer rotor portion 232 (tooth shape is indicated by a broken line) on the back side of the drawing is centered on the rotation center A with respect to the first outer rotor portion 231 (tooth shape is indicated by a solid line) on the front side of the drawing. Fig. 6 shows a state in which it is slightly shifted in the direction of arrow R1. However, the gap between the external teeth 221 and the first internal teeth 231a (second internal teeth 232a) at the position P1 and the position Q1 is smaller than that of the oil pump 100 (see FIG. 3). Further, in the oil pump 200, the number of contact points between the external teeth 221 and the internal teeth (the first internal teeth 231a and the second internal teeth 232a) is larger than that in the oil pump 100. That is, the inside of the pump is partitioned by a larger volume chamber V, and the inner rotor 220 and the outer rotor 230 are rotated while contacting each other at a total of 12 positions P1 to P6 and positions Q1 to Q6. As described above, the inner rotor 220 and the outer rotor 230 are rotated in a multipoint contact state, but the oil pump 200 itself is rotationally driven in a state filled with the lubricating oil, so that the wear resistance at the contact point is sufficiently excellent. Yes.

  In the oil pump 200, the structure around the inner rotor 220 including the O-ring 36 is the same as that in the first embodiment except that the tooth profile is formed by a trochoid curve.

  In the second embodiment, the following effects can be obtained.

  In the second embodiment, as described above, the oil pump 200 is configured using the inner rotor 220 and the outer rotor 230 whose tooth forms are formed by trochoidal curves. Then, in the outer rotor 230, the first outer rotor portion 231, the second outer rotor portion 232, the first inner teeth 231a of the first outer rotor portion 231 and the second inner teeth 232a of the second outer rotor portion 232 are shifted in the rotational direction. Thus, the first outer rotor portion 231 and the second outer rotor portion 232 are configured by the torsion spring 35 that urges the first outer rotor portion 231 and the second outer rotor portion 232. Thus, also in the trochoid oil pump 200, the outer teeth 221 of the inner rotor 220 are sandwiched between the first inner teeth 231a of the first outer rotor portion 231 and the second inner teeth 232a of the second outer rotor portion 232, and are driven to rotate. Can do. Therefore, it is possible to reliably prevent the inner rotor 220 and the outer rotor 230 from rattling due to the gap between the outer teeth 221 and the inner teeth (the first inner teeth 231a and the second inner teeth 232a). The rattling noise (abnormal noise) between 220 and the outer rotor 230 can be effectively reduced. Furthermore, the intensity of the pulsation of discharge pressure (periodic fluctuation of the discharge pressure) can be mitigated using the biasing force (compression deformation) of the torsion spring 35. The remaining effects of the second embodiment are similar to those of the aforementioned first embodiment.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is shown not by the above description of the embodiment but by the scope of claims for patent, and further includes all modifications (modifications) within the meaning and scope equivalent to the scope of claims for patent.

  For example, in the first and second embodiments, the metal torsion spring 35 is used. Further, in the first modification of the first embodiment, a metal coil spring 55 is used, and in the second modification of the first embodiment, an example using a metal leaf spring 75 is shown. However, the present invention is not limited to this. If the urging member is capable of urging the “first outer rotor portion” and the “second outer rotor portion” of the present invention, the “biasing member” of the present invention is made using an elastically deformable material other than metal. May be configured.

  In the first embodiment, the first and second modifications of the first embodiment, and the second embodiment, one end of the crankshaft 93 is connected to the shaft insertion hole 22 ( 222), the oil pump 100 (200) is rotationally driven. However, the present invention is not limited to this. For example, the driving force of the crankshaft 93 is taken out via the belt / pulley mechanism, and the oil pump is rotated by inserting (fixing) the driving shaft attached to the pulley shaft center into the shaft insertion hole 22 of the inner rotor 20. The present invention can be applied to various configurations. Further, when the drive shaft is provided integrally with the inner rotor 20, the “attenuation member” of the present invention may not be provided.

  In the first embodiment, the first and second modifications of the first embodiment, and the second embodiment, an example in which the outer rotor 30 (50, 70, 230) has a two-part structure has been described. However, the present invention is not limited to this. The outer rotor may be divided into a plurality of three or more outer rotor portions. In this case, an urging member such as a torsion spring 35 may be individually attached so that each outer rotor portion is displaced in the rotational direction.

  In the first embodiment, the first modification and the second modification of the first embodiment, and the second embodiment, an annular O is formed in the gap S between the inner rotor 20 (220) and the crankshaft 93. Although an example in which the ring 36 (236) is arranged has been described, the present invention is not limited to this. If it is possible to align the rotation center A of the inner rotor 20 with respect to the rotation center of the crankshaft 93, the “attenuation members” of the present invention need only be disposed in at least three locations in the gap S. That is, what is necessary is just to comprise so that the outer peripheral surface 93a of the crankshaft 93 may be enclosed in partial arc shape using the "attenuation member" of this invention.

  In the first embodiment, the first and second modifications of the first embodiment, and the second embodiment, the outer teeth 21 (221) of the inner rotor 20 (220) and the outer rotor 30 (250, 70). , 30) of the internal teeth (the first internal teeth 31a (51a, 71a, 231a) and the second internal teeth 32a (52a, 72a, 232a)) are engaged with each other so as to linearly extend in the X-axis direction. Although an example in which the present invention is applied to 100 (200) is shown, the present invention is not limited to this. That is, the present invention is applied to an internal gear type oil pump composed of an inner rotor and an outer rotor having a helical shape in which the tooth surface shape is rotated around the X axis at a predetermined rate and continues from one end surface to the other end surface. May be.

  In the first embodiment, the first modification and the second modification of the first embodiment, and the second embodiment, the inner rotor 20 (220) and the outer rotor 30 (50, 70, 230) using an aluminum alloy. However, the present invention is not limited to this. For example, the inner rotor 20 (220) and the outer rotor 30 (50, 70, 230) may be configured using a resin material.

  In the first embodiment, the first and second modifications of the first embodiment, and the second embodiment, the first outer rotor portion 31 (51, 71, 231) divided into two and the second are divided. Although an example in which the thickness (X-axis direction) of the outer rotor portion 32 (52, 72, 232) is configured to be equal to each other has been shown, the present invention is not limited to this. For example, the thickness of the first outer rotor portion 31 and the thickness of the second outer rotor portion 32 may be different from each other. Although the balance with the urging force of the torsion spring 35 (the urging member) is obtained, when the thickness of the second outer rotor portion 32 is smaller than the thickness of the first outer rotor portion 31, the second outer rotor portion is caused by a smaller urging force. 32 can be rotationally moved in the forward and reverse directions with respect to the first outer rotor portion 31. Even in this case, it is possible to reliably prevent the inner rotor 20 and the outer rotor 30 from rattling with each other due to the gap between the outer teeth 21 and the inner teeth (the first inner teeth 31a and the second inner teeth 32a). it can.

  In the first embodiment, the first and second modifications of the first embodiment, and the second embodiment, the X-axis direction of the shaft insertion hole 22 (222) in the inner rotor 20 (220) is used. Although an example in which the O-ring 36 (236) is fitted in the accommodating portion 22b formed in the central portion is shown, the present invention is not limited to this. For example, within the shaft insertion hole 22, the O-ring 36 may be arranged close to the X2 side or the X1 side other than the central portion of the shaft insertion hole 22.

  In the first embodiment, the first and second modifications of the first embodiment, and the second embodiment, an oil pump 100 that supplies oil (lubricating oil) 1 to the engine 90 (internal combustion engine). Although the example in which the present invention is applied is shown in (200), the present invention is not limited to this. For example, the present invention may be applied to an oil pump for supplying AT fluid (AT oil) to an automatic transmission (AT) that automatically switches the gear ratio according to the rotational speed of the internal combustion engine. Further, unlike the AT (multi-stage transmission) that changes gears by changing the gear combination, the lubricating oil is supplied to the sliding portion in the continuously variable transmission (CVT) capable of changing the gear ratio continuously and continuously. The present invention may be applied to an oil pump for this purpose. Further, the present invention may be applied to an oil pump for supplying power steering oil to a power steering device that drives a steering (steering device) in a vehicle.

  In the first embodiment, the first modification and the second modification of the first embodiment, and the second embodiment, the oil pump 100 (200) is installed in a vehicle such as an automobile including the engine 90 (internal combustion engine). However, the present invention is not limited to this. For example, you may apply this invention with respect to the oil pump mounted in equipment other than the vehicle provided with the internal combustion engine (engine). Moreover, as an internal combustion engine, a gasoline engine, a diesel engine, a gas engine, etc. are applicable.

  Moreover, in the said 2nd Embodiment, it showed about the example which applied this invention to the oil pump 200 with which the tooth profile of the external tooth 221 and the internal tooth (1st internal tooth 231a and the 2nd internal tooth 232a) was formed of the trochoid curve. However, the present invention is not limited to this. That is, the present invention may be applied to an internal gear type oil pump in which tooth shapes of external teeth and internal teeth are formed by a cycloid curve.

DESCRIPTION OF SYMBOLS 1 Oil 10 Casing part 11a Suction port 12b Discharge port 20,220 Inner rotor 21,221 External tooth 30,50,70,230 Outer rotor 31,51,71,231 1st outer rotor part 31a, 51a, 71a, 231a 1st internal tooth 32, 52, 72, 232 Second outer rotor portion 32a, 52a, 72a, 232a Second internal tooth 35 Torsion spring (biasing member)
36 O-ring (damping member)
40 Pump cover 55 Coil spring (biasing member)
75 Leaf spring (biasing member)
90 Engine 93 Crankshaft 93a Outer peripheral surface 93s Cross section 100, 200 Oil pump

Claims (5)

An inner rotor having external teeth;
An outer rotor having inner teeth that mesh with the outer teeth of the inner rotor,
The outer rotor is
A first outer rotor portion having first internal teeth;
A second outer rotor portion that is coaxially rotatable with respect to the first outer rotor portion and is disposed so as to overlap in a state of being shifted in the rotational direction, and having second internal teeth;
An urging member that urges the first outer rotor portion and the second outer rotor portion such that the first inner teeth of the first outer rotor portion and the second inner teeth of the second outer rotor portion are displaced from each other in the rotational direction; Including,
In a state where the first outer rotor portion and the second outer rotor portion are biased by the biasing member, the inner rotor is formed by the first inner teeth of the first outer rotor portion and the second inner teeth of the second outer rotor portion. The oil pump is configured so that the external teeth of the motor are sandwiched.   2. The oil pump according to claim 1, wherein the outer rotor has a two-part structure constituted by the first outer rotor portion and the second outer rotor portion.   The urging member is disposed between the first outer rotor portion and the second outer rotor portion so as to urge the first outer rotor portion and the second outer rotor portion in opposite rotation directions. Item 3. The oil pump according to Item 1 or 2. A crankshaft is inserted into the inner rotor,
The clearance gap between the said inner rotor and the said crankshaft is arrange | positioned in the state elastically deformed while contacting the said inner rotor and the said crankshaft, and further provided with the damping member which has a spring property. Oil pump as described in the paragraph.   5. The oil pump according to claim 4, wherein the damping member is disposed so as to surround the outer peripheral surface of the crankshaft in a circumferential manner in a state in contact with the outer peripheral surface of the crankshaft.

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