JP2023151340A - Reciprocating rotation converting mechanism, and motor pump and engine using the same - Google Patents

Abstract

To reduce friction resistance and improve conversion efficiency.SOLUTION: A converting mechanism 150 for converting reciprocation of a piston 132 to rotation of a rotary member 133 comprises a regulation mechanism 160 for regulating the rotation of the piston 132 relative to a cylinder 131. The regulation mechanism 160 has: an axial direction groove 161 disposed on either one of a cylinder 131 and a piston 132 and formed so that an axial direction D1 becomes a longitudinal direction; a shaft member 153 disposed so as to regulate a relative movement in the axial direction D1 and a rotation direction with respect to the other one of the cylinder 131 and the piston 132, and guided in the axial direction D1 by the axial direction groove 161; and a rolling member 162 disposed so as to interposing between the axial direction groove 161 and the shaft member 153.SELECTED DRAWING: Figure 1

Description

This technology relates to a reciprocating rotation conversion mechanism that converts reciprocating motion and rotational motion, and an electric pump and internal combustion engine using the same.

BACKGROUND ART Conventionally, pump devices have been widely used that convert rotation of an electric motor into reciprocating motion of a piston to suck air, pressurize it, and discharge it. In recent years, a pump device has been developed in which a piston is arranged inside a substantially cylindrical rotating member rotated by a motor, and the rotational axis direction of the rotating member is aligned with the reciprocating direction of the piston (see Patent Document 1). ). This pump device uses a conversion mechanism to convert the rotation of the rotating member into reciprocation of the piston.

This conversion mechanism has a cam groove formed on the inner circumferential surface of a rotating member and a cam follower provided to protrude radially from the piston.The rotation of the rotating member causes the cam follower to move the piston back and forth along the cam groove. By being guided in the direction, the piston is made to reciprocate. In addition, in this conversion mechanism, in order to prevent the piston from rotating relative to the cylinder, a shaft-like member forming a cam follower that protrudes radially from the piston is inserted into an elongated hole formed in the cylinder whose longitudinal direction is the reciprocating direction. While reciprocating, it prevents the piston from rotating.

Japanese Patent Application Publication No. 2008-223513

However, in the configuration described in Patent Document 1, regarding the configuration for preventing rotation of the piston, the shaft-like member protruding radially from the piston is provided directly in the elongated hole of the cylinder, so when the shaft-like member reciprocates, There is a risk that frictional resistance may occur due to sliding contact with the inner surface of the elongated hole. In order to improve the conversion efficiency between rotation and reciprocation, it has been desired to reduce frictional resistance.

Therefore, it is an object of the present invention to provide a reciprocating rotation conversion mechanism capable of reducing frictional resistance and improving conversion efficiency, and an electric pump and internal combustion engine using the same.

This reciprocating rotation conversion mechanism includes a cylinder, a piston disposed to be able to reciprocate in the axial direction within the cylinder, a rotating member disposed to be coaxially rotatable around the piston, the piston and the rotating member. a conversion mechanism that converts the reciprocation of the piston and the rotation of the rotating member, the conversion mechanism being disposed on one of the piston and the rotating member, and arranged on the entire circumference of the rotating member in the rotational direction. and a roller portion that is disposed on the other of the piston and the rotating member and that is fitted into and guided by the corrugated groove. a conversion mechanism; and a restriction mechanism that restricts rotation of the piston relative to the cylinder, the restriction mechanism being disposed on one of the cylinder and the piston, and the axial direction being the longitudinal direction. an axial groove formed so as to be arranged so as to restrict relative movement in the axial direction and the rotational direction with respect to the other of the cylinder and the piston; It has a shaft guided in the direction, and a rolling member disposed to be interposed between the axial groove and the shaft.

This reciprocating rotation conversion mechanism includes a cylinder, a piston disposed to be able to reciprocate in the axial direction within the cylinder, a rotating member disposed to be coaxially rotatable around the piston, the piston and the rotating member. a conversion mechanism that converts the reciprocation of the piston and the rotation of the rotating member, the conversion mechanism being disposed on one of the piston and the rotating member, and arranged on the entire circumference of the rotating member in the rotational direction. and a roller portion that is disposed on the other of the piston and the rotating member and that is fitted into and guided by the corrugated groove. a conversion mechanism; and a restriction mechanism that restricts rotation of the piston relative to the cylinder, the wave-shaped groove having a first groove facing one side in the axial direction over the entire circumference in the rotation direction. a cam surface, and a second cam surface facing the other side in the axial direction over the entire circumference in the rotational direction, and the roller section has a second cam surface that is guided in contact with the first cam surface. 1 roller, and a second roller that is guided in contact with the second cam surface.

This reciprocating rotation conversion mechanism includes a cylinder, a piston disposed to be able to reciprocate in the axial direction within the cylinder, a rotating member disposed to be coaxially rotatable around the piston, the piston and the rotating member. a conversion mechanism that converts the reciprocation of the piston and the rotation of the rotating member, the conversion mechanism being disposed on one of the piston and the rotating member, and arranged on the entire circumference of the rotating member in the rotational direction. and a roller portion that is disposed on the other of the piston and the rotating member and that is fitted into and guided by the corrugated groove. a conversion mechanism; and a restriction mechanism that restricts rotation of the piston relative to the cylinder, the wave-shaped groove having a first groove facing one side in the axial direction over the entire circumference in the rotation direction. a cam surface, and a second cam surface facing the other side in the axial direction over the entire circumference in the rotational direction, and the first cam surface has an outer diameter side in the radial direction of the piston and an inner diameter side. The second cam surface has a slope where the outer diameter side in the radial direction is farther away from the first cam surface than the inner diameter side, and the roller portion , has an outer circumferential surface having a slope such that the outer diameter side in the radial direction has a larger diameter than the inner diameter side.

This electric pump includes the above-mentioned reciprocating rotation conversion mechanism and a pump section that sucks, pressurizes, and discharges fluid by the reciprocating motion of the piston, and the rotating member rotates integrally with the rotor of the electric motor.

The present internal combustion engine includes the reciprocating rotation conversion mechanism described above, and a fuel combustion mechanism that presses the piston to obtain output by burning fuel in the cylinder, and the rotating member outputs driving force to the outside. This is the output shaft.

According to the present reciprocating rotation conversion mechanism and the electric pump and internal combustion engine using the same, frictional resistance can be reduced and conversion efficiency can be improved.

(a) is a cross-sectional view showing the electric pump according to the first embodiment, and (b) is a developed view showing corrugated grooves. It is a sectional view showing an electric pump concerning a 2nd embodiment. It is a sectional view showing an electric pump concerning a 3rd embodiment. FIG. 3 is a sectional view showing an internal combustion engine according to a fourth embodiment. (a) is a plan view showing a fuel combustion mechanism of an internal combustion engine according to a fourth embodiment, and (b) is a developed view showing a switching groove. FIG. 7 is a sectional view showing an internal combustion engine according to a fifth embodiment. FIG. 7 is a developed view showing wave-shaped grooves according to a fifth embodiment. FIG. 7 is a sectional view showing an internal combustion engine according to a sixth embodiment. FIG. 7 is a developed view showing wave-shaped grooves according to a sixth embodiment.

<First embodiment>
Hereinafter, a first embodiment of the present disclosure will be described in detail with reference to FIGS. 1(a) and (b). In this embodiment, a case will be described in which the reciprocating rotation conversion mechanism 130 is applied to the electric pump 100. First, an outline of the electric pump 100 will be explained using FIG. 1(a). The electric pump 100 is an electric axial pump and includes a case 110, an electric motor 120, a reciprocating rotation conversion mechanism 130, and a pump section 140. In addition, in this embodiment, the rotation center of the rotor 123 of the electric motor 120 and the center line of the piston 132 of the reciprocating rotation conversion mechanism 130 coincide, and this is defined as the center line C1, and the direction along this center line C1 is is defined as the axial direction D1. Further, for convenience of explanation, it is assumed that the axial direction D1 faces an upward direction Du and a downward direction Dd. Note that, of course, the axial direction D1 is not limited to the vertical direction. Further, a direction perpendicular to the center line C1 of the piston is defined as a radial direction D2 of the piston 132. Moreover, the electric pump 100 here can be applied to, for example, a vacuum pump, a water pump, an air compressor, and the like.

The electric motor 120 includes a stator 121 fixed to the case 110 and a rotor 123 rotatably provided inside the stator 121. Stator 121 has a magnet 122 attached to case 110. The rotor 123 has a cylindrical rotor core 124 rotatably provided around a center line C1, and a coil 125 wound around the rotor core 124. Rotor core 124 is rotatably supported by case 110 by bearings. Further, the electric motor 120 is provided with a brush 126 that is connected to the external power source 101 and switches energization to the coil 125 .

The reciprocating rotation conversion mechanism 130 includes a cylinder 131 fixed to the case 110 , a piston 132 arranged so as to be reciprocated in the axial direction D1 within the cylinder 131 (inside the cylinder), and a cylindrical rotating member rotated by the rotor 123 133, a conversion mechanism 150 that is interposed between the piston 132 and the rotating member 133 and converts the reciprocation of the piston 132 and the rotation of the rotating member 133, and a regulation that restricts the piston 132 from rotating relative to the cylinder 131. It has a mechanism 160. Details of the reciprocating rotation conversion mechanism 130 will be described later.

The case 110 includes a case body 111, a cylinder case 112 fixed to the case body 111, and a cylinder cover 113 that closes the cylinder case 112. The cylinder case 112 has a cylindrical portion 112a and a bottom portion 112b that form the cylinder 131, and a lid portion 112c that closes the opening of the case body 111. The piston 132 forms a first working chamber S1 together with the cylindrical portion 112a and the bottom portion 112b. The cylinder cover 113 is fitted into the cylinder 131, and together with the cylindrical portion 112a and the piston 132 forms a second working chamber S2.

The pump section 140 sucks fluid by reciprocating the piston 132, pressurizes it, and discharges it. In this embodiment, the fluid is air, and the pump section 140 has an intake passage a1 communicating from the outside to the inside of the case 110, and a first working chamber S1 from the inside of the case 110 via the cylinder case 112 and the piston 132. A first intake passage a2 communicating with each other, a second intake passage a3 communicating with the second working chamber S2 from the inside of the case 110 via the cylinder case 112 and the piston 132, and a bottom part 112b of the cylinder case 112 from the first working chamber S1. The first exhaust passage a4 communicates with the outside via the cylinder cover 113, and the second exhaust passage a5 communicates with the outside from the second working chamber S2 through the cylinder cover 113. The first intake path a2 is provided with a check valve b1 that allows only air to be taken into the first working chamber S1 to flow, and the second intake path a3 is provided with a check valve b1 that allows only air to be taken into the second working chamber S2 to flow through. A check valve b2 for circulating air is provided, a check valve b3 for circulating only the air discharged from the first working chamber S1 is provided for the first exhaust passage a4, and a check valve b3 for circulating only the air discharged from the first working chamber S1 is provided for the second exhaust passage a5. A check valve b4 is provided that allows only the air discharged from the working chamber S2 to flow through.

Therefore, in this electric pump 100, when electric power is supplied to the electric motor 120, the rotor 123 rotates, and the rotation of the rotor 123 is converted into reciprocation of the piston 132 by the reciprocating rotation conversion mechanism 130. In the first working chamber S1, air is sucked in from the outside through the first intake path a2 during expansion, and when compressed, the air inside the room is pressurized and discharged to the outside through the first exhaust path a4. In the second working chamber S2, air is sucked in from the outside through the second intake path a3 during expansion, and when compressed, the indoor air is pressurized and discharged to the outside through the second exhaust path a5.

[Reciprocating rotation conversion mechanism]
Next, the reciprocating rotation conversion mechanism 130 will be explained in detail. The rotating member 133 is disposed coaxially and rotatably around the piston 132, and is attached to the rotor 123 of the electric motor 120 to rotate together with the rotor 123. The conversion mechanism 150 includes a wave-shaped groove 151 formed in the rotating member 133 and a roller portion 152 formed in the piston 132. The wave-shaped groove 151 has a wave shape that is alternately displaced in the axial direction D1 over the entire circumference of the rotating member 133 in the rotational direction (see FIG. 1(b)). A shaft member 153 that penetrates in the radial direction D2 and has both ends projecting in the radial direction D2 is provided at the center of the piston 132 in the axial direction D1. The roller portion 152 is a roller that is rotatably provided at both ends of the shaft member 153 and includes a rolling element therein, and is fitted into the corrugated groove 151 and guided. Since the roller portion 152 includes a rolling element, the sliding resistance with respect to the corrugated groove 151 can be reduced. Further, the outer circumferential surface of the roller portion 152 is a circumferential surface parallel to the radial direction D2, and the cam surfaces on both sides of the corrugated groove 151 in the axial direction D1 are surfaces parallel to the radial direction D2. There is.

In this embodiment, a case is described in which the wave-shaped groove 151 is formed on the rotating member 133 and the roller portion 152 is provided on the piston 132, but the present invention is not limited to this. The roller portion 152 may be provided on the rotating member 133 (see the third embodiment). That is, the wave-shaped groove 151 is arranged on one of the piston 132 and the rotating member 133, and the roller part 152 is arranged on the other of the piston 132 and the rotating member 133.

The regulating mechanism 160 includes an axial groove 161 formed in the cylinder 131, a shaft member 153 that is an example of a shaft disposed on the piston 132, and a rolling member 162 provided on the shaft member 153. . The axial groove 161 is formed so that the axial direction D1 is the longitudinal direction and extends through the cylinder 131 in the radial direction D2. The shaft member 153 is restricted from relative movement in the axial direction D1 and the rotational direction with respect to the piston 132, and is guided in the axial direction D1 by engaging with the axial groove 161. The rolling member 162 is a member such as a ball bearing or a roller bearing that is rotatably attached to the shaft member 153 and includes a rolling element therein. Reduce friction. In this embodiment, the rolling member 162 is arranged closer to the piston 132 than the roller portion 152 (on the inner diameter side in the radial direction D2).

In this embodiment, a case is described in which the axial groove 161 is formed in the cylinder 131 and the shaft member 153 is provided in the piston 132; however, the present invention is not limited to this. The shaft member 153 may be formed in the cylinder 131 (see the second embodiment). That is, the axial groove 161 is arranged on one of the cylinder 131 and the piston 132, and the shaft member 153 is arranged on the other of the cylinder 131 and the piston 132. Further, in this embodiment, the case has been described in which the rolling member 162 is provided in the shaft member 153, but the rolling member 162 is not limited to this, and may be provided in the axial groove 161. Furthermore, in the present embodiment, a case has been described in which the roller part 152 and the rolling member 162 are attached to one shaft member 153, but the invention is not limited to this, and the shaft member to which the roller part 152 is attached is It may be separate from the shaft member to which the rolling member 162 is attached (see the second embodiment).

In the reciprocating rotation conversion mechanism 130 described above, the rotating member 133 rotates due to the rotation of the rotor 123, thereby rotating the corrugated groove 151 and moving the shaft member 153 via the roller portion 152. At this time, since the shaft member 153 is restricted from moving in the rotational direction by the axial groove 161, the shaft member 153 only moves back and forth in the axial direction D1. This causes the piston 132 to reciprocate and operate as a pump. In this embodiment, the case where the reciprocating rotation conversion mechanism 130 converts rotation into reciprocation has been described, but the present invention is not limited to this, and it is also possible to convert reciprocation into rotation. That is, by reciprocating the piston 132 by external force, the shaft member 153 can rotate the wave-shaped groove 151, and the rotating member 133 can also be rotated.

As explained above, according to the reciprocating rotation conversion mechanism 130 of this embodiment, since the rolling member 162 is provided between the shaft member 153 and the axial groove 161, the rolling member 162 is not provided. The frictional resistance in the regulating mechanism 160 can be suppressed compared to the case where there is no such structure. Therefore, the conversion efficiency between rotation and reciprocation can be improved, and the electricity consumption of the electric pump 100 can be improved.

Moreover, according to the electric pump 100 of this embodiment, since the pump part 140 is built into the hollow motor, compared to the case where the electric motor 120 and the pump part 140 are arranged side by side in the axial direction D1, The entire device can be made smaller.

<Second embodiment>
Next, a second embodiment of the present disclosure will be described in detail with reference to FIG. 2. In this embodiment, the outer circumferential surface 252a of the roller portion 252 is a sloped surface having a slope with respect to the radial direction D2, and the cam surfaces 251a and 251b on both sides of the corrugated groove 251 in the axial direction D1 are both rollers. The outer circumferential surface 252a of the portion 252 is a sloped surface with respect to the radial direction D2, and the axial groove 261 is formed in the piston 232, and the shaft 263 is fixed to the cylinder 231. The configuration is different from the first embodiment. The electric pump 200 in this embodiment is an electric axial pump, and includes a case 110, an electric motor 120, a reciprocating rotation conversion mechanism 230, and a pump section 140. Since the pump section 140 is the same as that in the first embodiment, the reference numerals are the same and detailed description thereof will be omitted.

The reciprocating rotation conversion mechanism 230 of this embodiment will be described in detail. The reciprocating rotation conversion mechanism 230 includes a cylinder 231 fixed to the case 110, a piston 232 arranged so as to be reciprocated in the axial direction D1 within the cylinder 231, a cylindrical rotating member 233 rotated by the rotor 123, and a piston. 232 and the rotating member 233, a conversion mechanism 250 that converts the reciprocation of the piston 232 and the rotation of the rotating member 233, and a regulating mechanism 260 that restricts the rotation of the piston 232 with respect to the cylinder 231; have.

The rotating member 233 is arranged coaxially and rotatably around the piston 232, and is attached to the rotor 123 of the electric motor 120 to rotate together with the rotor 123. The conversion mechanism 250 includes a wave-shaped groove 251 formed on the rotating member 233 and a roller portion 252 formed on the piston 232. The wave-shaped groove 251 has a wave shape that is alternately displaced in the axial direction D1 over the entire circumference of the rotating member 233 in the rotation direction (see FIG. 1(b)).

A through hole 232a penetrating in the radial direction D2 is formed in the center of the piston 232 in the axial direction D1. The through hole 232a includes a pair of rotatable shaft-shaped roller portions 252 that protrude to one side in the radial direction D2, and a bearing 253 that supports the roller portion 252 rotatably around the radial direction D2 with respect to the piston 232. It is provided. That is, the tips of separate roller portions 252 protrude from both sides of the piston 232 in the radial direction D2, and are respectively fitted into and guided by the corrugated grooves 251. The bearing 253 is made of, for example, a needle bearing. Therefore, the resistance during rotation of the roller portion 252 can be reduced.

The regulating mechanism 260 includes an axial groove 261 formed in the piston 232, a shaft 263 disposed in the cylinder 231, and a rolling member 262 provided in the shaft 263. The axial groove 261 is formed so that the axial direction D1 is the longitudinal direction and penetrates the piston 232 in the radial direction D2. The shaft 263 is restricted from relative movement in the axial direction D1 and the rotational direction with respect to the cylinder 231, and is engaged with the axial groove 261 and guided in the axial direction D1. The rolling member 262 is a member such as a ball bearing or a roller bearing that is rotatably attached to the shaft 263 and includes a rolling element therein, and prevents friction between the shaft 263 and the axial groove 261. reduce In this embodiment, when viewed from the axial direction D1, the roller portion 252 and the shaft 263 are arranged to be shifted by about 90 degrees about the center line C1.

Here, the contact portion (contact line) between the cam surface of the wave-shaped groove 251 and the outer circumferential surface of the roller portion 252 will be considered. In this contact portion, the moving distance with respect to the rotation angle of the rotating member 233 differs depending on whether the distance from the center line C1 is far or close. That is, the moving distance of the rotating member 233 relative to the rotation angle is longer at a position farther from the center line C1 than at a closer position. Therefore, if the line of contact between the cam surface of the wave-shaped groove 251 and the outer circumferential surface of the roller portion 252 is parallel to the radial direction D2, slipping will occur at a position far from the center line C1 and at a position close to the center line C1. There is a risk that frictional resistance will increase. Therefore, in this embodiment, the diameter of the contact portion is made different between a position far from the center line C1 and a position close to the center line C1 to reduce the occurrence of slippage and thereby reduce the frictional resistance.

Specifically, the wave-shaped groove 251 has a first cam surface 251a facing the upper Du side, which is one side in the axial direction D1, over the entire circumference in the rotational direction, and a first cam surface 251a facing the upper direction Du side, which is one side in the axial direction D1, over the entire circumference in the rotational direction. It has a second cam surface 251b facing the downward direction Dd, which is the other side of D1. The first cam surface 251a has a slope such that the outer diameter side in the radial direction D2 is farther from the second cam surface 251b than the inner diameter side. The second cam surface 251b has a slope such that the outer diameter side in the radial direction D2 is farther from the first cam surface 251a than the inner diameter side. The roller portion 252 has an outer circumferential surface 252a having a slope such that the outer diameter side in the radial direction D2 has a larger diameter than the inner diameter side at a portion that contacts the wave-shaped groove 251, and the first cam surface 251a and the second cam They are provided with the same slope angle so as to be in line contact with the surface 251b.

Here, the inclination angle at which no slippage occurs between the outer diameter side and the inner diameter side in the radial direction D2 changes depending on the inclination angle of the corrugated groove 251 with respect to the rotation direction. For example, when the inclination angle of the corrugated groove 251 is parallel to the rotation direction, the inclination angle at which no slippage occurs is the maximum (hereinafter referred to as the maximum slope), and the inclination angle of the corrugated groove 251 is inclined with respect to the rotation direction. The smaller the slope angle at which no slipping occurs. In other words, the maximum slope is the slope angle at which the roller portion 252 does not slip on the outer diameter side and the inner diameter side with respect to the first cam surface 251a and the second cam surface 251b at a portion along the rotation direction of the corrugated groove 251. means. On the other hand, although the inclination angle of the cam surface can be changed depending on the position, the inclination angle of the roller portion 252 is always the same. Therefore, even if the inclination angle of the cam surface is changed depending on the position in correspondence with the inclination angle of the wave-shaped groove 251, since the inclination angle of the roller portion 252 is constant, there is a risk that point contact may occur depending on the location. Therefore, there is a possibility that the frictional resistance cannot be reduced sufficiently. Therefore, in this embodiment, the slope between the first cam surface 251a, the second cam surface 251b, and the outer circumferential surface 252a of the roller portion 252 is a slope angle that is smaller than the maximum slope and is smaller than the angle parallel to the radial direction D2. For example, the angle is set to be an intermediate angle between the maximum slope and parallel. Incidentally, the slope angle is not limited to an intermediate angle between the maximum slope and parallel; for example, the slope angle may be such that the waveform groove 251 makes a line contact at a portion where the waveform groove 251 is obliquely straight with respect to the rotation direction; It can be set appropriately between the angle and the maximum slope angle, or between the maximum slope and parallel.

As explained above, according to the reciprocating rotation conversion mechanism 230 of this embodiment, the first cam surface 251a, the second cam surface 251b, and the outer circumferential surface 252a of the roller portion 252 all have a slope. Frictional resistance in the conversion mechanism 250 can be suppressed compared to the case where the conversion mechanism 250 is not provided. Therefore, the conversion efficiency between rotation and reciprocation can be improved, and the electricity consumption of the electric pump 200 can be improved.

Further, according to the reciprocating rotation conversion mechanism 230 of this embodiment, the slope between the first cam surface 251a, the second cam surface 251b, and the outer circumferential surface 252a of the roller portion 252 is set as an angle between the maximum slope and parallel. There is. Therefore, compared to the maximum slope or parallel cases, it is possible to increase the proportion of slippage between the first cam surface 251a, the second cam surface 251b, and the outer circumferential surface 252a of the roller portion 252, thereby reducing frictional resistance. be able to.

<Third embodiment>
Next, a third embodiment of the present disclosure will be described in detail with reference to FIG. 3. This embodiment differs in configuration from the second embodiment in that a wave-shaped groove 351 is formed on the piston 332 and a roller portion 352 is provided on the rotating member 333. The electric pump 300 in this embodiment is an electric axial pump, and includes a case 110, an electric motor 120, a reciprocating rotation conversion mechanism 330, and a pump section 140. Since the pump section 140 is the same as that in the first and second embodiments, the reference numerals are the same and detailed description thereof will be omitted.

The reciprocating rotation conversion mechanism 330 of this embodiment will be described in detail. The reciprocating rotation conversion mechanism 330 includes a cylinder 331 fixed to the case 110, a piston 332 arranged so as to be reciprocated in the axial direction D1 within the cylinder 331, a cylindrical rotating member 333 rotated by the rotor 123, and a piston. 332 and the rotating member 333, a conversion mechanism 350 that converts the reciprocation of the piston 332 and the rotation of the rotating member 333, and a regulating mechanism 360 that restricts the rotation of the piston 332 with respect to the cylinder 331; have. The rotating member 333 is arranged coaxially and rotatably around the piston 332, and is attached to the rotor 123 of the electric motor 120 to rotate together with the rotor 123. The regulating mechanism 360 includes an axial groove 361 formed in the piston 332, a shaft 363 disposed in the cylinder 331, and a rolling member 362 provided in the shaft 363. The rolling member 362 is a member such as a ball bearing or a roller bearing that is rotatably attached to the shaft 363 and includes a rolling element therein, and prevents friction between the shaft 363 and the axial groove 361. reduce

The conversion mechanism 350 has a wave-shaped groove 351 formed in the piston 332 and a roller portion 352 formed in the rotating member 333. The wave-shaped groove 351 has a wave shape that is alternately displaced in the axial direction D1 over the entire circumference of the rotating member 333 in the rotation direction (see FIG. 1(b)). A support hole 333a formed in the radial direction D2 is formed in the center of the rotating member 333 in the axial direction D1. The support hole 333a includes a rotatable shaft-shaped roller portion 352 that protrudes toward the inner diameter side in the radial direction D2, and a bearing 353 that supports the roller portion 352 rotatably around the radial direction D2 with respect to the rotating member 333. , a pair are provided. That is, the tip portions of the separate roller portions 352 protrude inside the rotating member 333 in the radial direction D2, and are fitted into the corrugated grooves 351 and guided. The bearing 353 is made of, for example, a needle bearing. Therefore, the resistance during rotation of the roller portion 352 can be reduced.

The wave-shaped groove 351 has a first cam surface 351a facing the upper direction Du side, which is one side in the axial direction D1, over the entire circumference in the rotation direction, and a first cam surface 351a facing the upper direction Du side, which is one side in the axial direction D1, over the entire circumference in the rotation direction. It has a second cam surface 351b facing a certain downward direction Dd. The first cam surface 351a has a slope such that the outer diameter side in the radial direction D2 is farther from the second cam surface 351b than the inner diameter side. The second cam surface 351b has a slope such that the outer diameter side in the radial direction D2 is farther from the first cam surface 351a than the inner diameter side. The roller portion 352 has an outer circumferential surface 352a having a slope such that the outer diameter side in the radial direction D2 has a larger diameter than the inner diameter side at a portion that contacts the wave-shaped groove 351, and the first cam surface 351a and the second cam It is provided so as to be in line contact with the surface 351b. The slope of the first cam surface 351a, the second cam surface 351b, and the outer circumferential surface 352a of the roller portion 352 is a slope angle that is smaller than the maximum slope and larger than the angle parallel to the radial direction D2, for example. , the angle is between the maximum slope and parallel. Incidentally, the slope angle is not limited to an intermediate angle between the maximum slope and parallel; for example, the slope angle may be such that the wave-shaped groove 351 makes a line contact at a portion that is obliquely straight with respect to the rotation direction, or this slope It can be set appropriately between the angle and the maximum slope angle, or between the maximum slope and parallel.

As explained above, according to the reciprocating rotation conversion mechanism 330 of this embodiment, the first cam surface 351a, the second cam surface 351b, and the outer circumferential surface 352a of the roller portion 352 all have a slope. Frictional resistance in the conversion mechanism 350 can be suppressed compared to the case where the conversion mechanism 350 does not have the above structure. Therefore, the conversion efficiency between rotation and reciprocation can be improved, and the electricity consumption of the electric pump 300 can be improved.

<Fourth embodiment>
Next, a fourth embodiment of the present disclosure will be described in detail with reference to FIG. 4 and FIGS. 5(a) and 5(b). This embodiment differs in configuration from the first to third embodiments in that a reciprocating rotation conversion mechanism 730 is applied to the internal combustion engine 700. First, an outline of the internal combustion engine 700 will be explained using FIG. 4. In this embodiment, internal combustion engine 700 is a four-stroke engine, and includes a case 710, a reciprocating rotation conversion mechanism 730, and a fuel combustion mechanism 770. Further, in this embodiment, there are three combinations of reciprocating rotation conversion mechanisms 730 and fuel combustion mechanisms 770, and a three-cylinder internal combustion engine 700 is configured. The three sets of reciprocating rotation conversion mechanisms 730 and fuel combustion mechanisms 770 have the same configuration except that the phases of the rotating members 733 are shifted by 120 degrees (240 degrees).

The reciprocating rotation conversion mechanism 730 includes a cylinder 731 fixed to a case 710, a piston 732 arranged so as to be reciprocated in the axial direction D1 within the cylinder 731, a cylindrical rotating member 733, and the piston 732 and the rotating member 733. A conversion mechanism 750 is interposed between the piston 732 and the rotation of the rotary member 733, and a restriction mechanism 760 is provided to restrict rotation of the piston 732 relative to the cylinder 731. Details of the reciprocating rotation conversion mechanism 730 will be described later.

The case 710 includes a case body 711, a cover 713 that closes an opening of the case body 711, and a cylinder case 712 fixed to the cover 713. The cylinder case 712 has a cylindrical portion 712a forming a cylinder 731 and a head 712b. Piston 732 forms combustion chamber 705 together with cylindrical portion 712a and head 712b.

The fuel combustion mechanism 770 burns fuel in the cylinder 731 to press the piston 732 and obtain output. As shown in FIGS. 4 and 5(a), the fuel combustion mechanism 770 includes an intake passage 771 for sucking air into the combustion chamber 705 from the outside, and an exhaust passage 771 for discharging exhaust gas from the combustion chamber 705 to the outside. It has a passage 772 and a switching mechanism 773 that switches between intake and exhaust. The suction passage 771 is formed in the head 712b and can communicate with the combustion chamber 705, so that air can be sucked in from the outside through the communication. The exhaust passage 772 is formed in the head 712b and can communicate with the combustion chamber 705, so that the exhaust gas can be discharged to the outside through the communication.

As shown in FIG. 5A, the cover 713 is formed with an inlet port 713a and an outlet port 713b that penetrate in the axial direction D1. The suction port 713a communicates with the suction valve 774 via a flow path (a part of the suction path 771) between the suction port 713a and the head 712b. The discharge port 713b communicates with a discharge valve 775 via a flow path (a part of the discharge path 772) between the discharge port 713b and the head 712b. A partition wall 712c is provided between the suction passage 771 and the discharge passage 772. Further, an injection 776 exposed to the combustion chamber 705 is provided in the center of the head 712b.

The switching mechanism 773 includes an intake valve 774, an exhaust valve 775, and a conversion mechanism 780. The suction valve 774 is a poppet valve provided in the head 712b, and opens and closes the suction passage 771 by reciprocating in the axial direction D1. The discharge valve 775 is a poppet valve provided in the head 712b, and opens and closes the discharge passage 772 by reciprocating in the axial direction D1. The conversion mechanism 780 is interposed between the suction valve 774 and the discharge valve 775 and the rotating member 733, and converts the rotation of the rotating member 733 into opening and closing of the suction valve 774 and the discharge valve 775. The conversion mechanism 780 includes a switching groove 781, a suction roller section 782, and a discharge roller section (not shown). The switching grooves 781 are wave-shaped cam grooves formed in the rotating member 733 and alternately displaced in the axial direction D1 over the entire circumference of the rotating member 733 in the rotational direction. An example of the switching groove 781 is shown in FIG. 5(b). The suction roller portion 782 is a shaft-shaped member that is provided to protrude from the suction valve 774 in the radial direction D2, and is fitted and guided in the switching groove 781. The discharge roller portion is a shaft-shaped member that is provided to protrude from the discharge valve 775 in the radial direction D2, and is fitted and guided in the switching groove 781.

The arrow shown in FIG. 5(a) indicates the rotation direction of the switching mechanism 773. In this switching mechanism 773, the rotating member 733 is rotated, and when air is taken in, the intake valve 774 is opened and the exhaust valve 775 is closed, so that the intake passage 771 and the combustion chamber 705 are communicated with each other, and the exhaust passage 772 and The combustion chamber 705 is cut off. When the rotating member 733 is rotated to discharge exhaust gas, the exhaust valve 775 is opened, and when the intake valve 774 is closed, the exhaust passage 772 and the combustion chamber 705 are communicated, and the intake passage 771 and the combustion chamber 705 are connected. and cut off.

[Reciprocating rotation conversion mechanism]
Next, the reciprocating rotation conversion mechanism 730 will be described in detail. The rotating member 733 is arranged to be rotatable coaxially around the piston 732. The conversion mechanism 750 has a wave-shaped groove 751 formed in a rotating member 733 and a roller portion 752 formed in a piston 732. The wave-shaped groove 751 has a wave shape that is alternately displaced in the axial direction D1 over the entire circumference of the rotating member 733 in the rotational direction (see FIG. 1(b)).

On the downward Dd side of the piston 732 in the axial direction D1, there is a rotatable shaft-shaped roller portion 752 that protrudes to one side in the radial direction D2, and the roller portion 752 is rotatable relative to the piston 732 around the radial direction D2. A pair of bearings 753 are provided to support the bearings. That is, the tips of separate roller portions 752 protrude from both sides of the piston 732 in the radial direction D2, and are respectively fitted into and guided by the wave-shaped grooves 751.

The regulating mechanism 760 includes an axial groove 761 formed in the piston 732, a shaft 763 disposed in the cylinder 731, and a rolling member 762 provided in the shaft 763. The axial groove 761 is formed so that the axial direction D1 is the longitudinal direction and extends through the piston 732 in the radial direction D2. The shaft 763 is restricted from relative movement in the axial direction D1 and rotational direction with respect to the cylinder 731, and is engaged with the axial groove 761 and guided in the axial direction D1. The rolling member 762 is, for example, a ball bearing or a roller bearing rotatably attached to the shaft 763, and reduces friction between the shaft 763 and the axial groove 761. In this embodiment, when viewed from the axial direction D1, the roller portion 752 and the shaft 763 are arranged so as to face in the same direction and overlap.

The wave-shaped groove 751 has a first cam surface 751a facing the upper direction Du side which is one side in the axial direction D1 over the entire circumference in the rotation direction, and a first cam surface 751a facing the upper direction Du side which is one side in the axial direction D1 over the entire circumference in the rotation direction. It has a second cam surface 751b facing a certain downward direction Dd. The first cam surface 751a has a slope such that the outer diameter side in the radial direction D2 is farther from the second cam surface 751b than the inner diameter side. The second cam surface 751b has a slope such that the outer diameter side in the radial direction D2 is farther from the first cam surface 751a than the inner diameter side. The roller portion 752 has an outer circumferential surface 752a having a slope such that the outer diameter side in the radial direction D2 has a larger diameter than the inner diameter side at a portion that contacts the wave-shaped groove 751. They are provided with the same slope angle so as to be in line contact with the surface 751b.

The slope of the first cam surface 751a, the second cam surface 751b, and the outer circumferential surface 752a of the roller portion 752 is set to a slope angle smaller than the maximum slope and larger than the angle parallel to the radial direction D2, for example. , the angle is between the maximum slope and parallel. Incidentally, the slope angle is not limited to an intermediate angle between the maximum slope and parallel; for example, the slope angle may be such that the waveform groove 751 makes a line contact with the part where the waveform groove 751 is obliquely straight with respect to the rotation direction, or this slope It can be set appropriately between the angle and the maximum slope angle, or between the maximum slope and parallel.

In this embodiment, gear portions 733a are formed on the outer peripheral surfaces of each of the three rotating members 733, and the gear portions 733a are sequentially meshed with each other with a phase shift of 120 degrees (240 degrees). Therefore, the three rotating members 733 rotate synchronously with the phases shifted, and can function as a three-cylinder internal combustion engine 700. Further, this internal combustion engine 700 has two output shafts, a first output shaft 701 and a second output shaft 702. The first output shaft 701 is formed integrally with one rotating member 733, and the second output shaft 702 is formed integrally with another rotating member 733.

As explained above, according to the reciprocating rotation conversion mechanism 730 of this embodiment, the first cam surface 751a, the second cam surface 751b, and the outer peripheral surface 752a of the roller portion 752 all have a slope. Frictional resistance in the conversion mechanism 750 can be suppressed compared to the case where the conversion mechanism 750 is not provided. Therefore, the rotational and reciprocating conversion efficiency can be improved, and the fuel efficiency of the internal combustion engine 700 can be improved.

Furthermore, according to the reciprocating rotation conversion mechanism 730 of the present embodiment, since the rolling member 762 is provided between the shaft 763 and the axial groove 761, the rolling member 762 is not provided. , frictional resistance in the regulating mechanism 760 can be suppressed. Therefore, the rotational and reciprocating conversion efficiency can be improved, and the fuel efficiency of the internal combustion engine 700 can be further improved.

<Fifth embodiment>
Next, a fifth embodiment of the present disclosure will be described in detail with reference to FIGS. 6 and 7. This embodiment differs in configuration from the fourth embodiment in that two pistons 1032 are arranged side by side in the axial direction D1 with their center lines C1 aligned. An overview of this internal combustion engine 1000 will be explained using FIG. 6. In this embodiment, internal combustion engine 1000 is a four-stroke engine, and includes a case 1010, a reciprocating rotation conversion mechanism 1030, and a fuel combustion mechanism 1070. In this embodiment, there are two combinations of the reciprocating rotation conversion mechanism 1030 and the fuel combustion mechanism 1070, and a two-cylinder internal combustion engine 1000 is configured. The two pistons 1032 constituting the two cylinders reciprocate toward and away from each other like a boxer engine. Moreover, the rotating member 1033 rotated by each piston 1032 is integrated. The two sets of reciprocating rotation conversion mechanisms 1030 and fuel combustion mechanisms 1070 have the same configuration except that the phases of the rotating members 1033 are shifted by 180 degrees.

The reciprocating rotation conversion mechanism 1030 includes a cylinder 1031 fixed to a case 1010, a piston 1032 arranged so as to be able to reciprocate in the axial direction D1 within the cylinder 1031, a cylindrical rotating member 1033, and the piston 1032 and the rotating member 1033. It has a conversion mechanism 1050 that is interposed between the piston 1032 and the rotation of the rotary member 1033, and a restriction mechanism 1060 that restricts the rotation of the piston 1032 with respect to the cylinder 1031. Details of the reciprocating rotation conversion mechanism 1030 will be described later.

The case 1010 is attached to each of the lower case 1011 forming the lower Dd side in the axial direction D1, the upper case 1013 connected to the lower case 1011 and forming the upper Du side, and the lower case 1011 and the upper case 1013. The cylinder case 1012 has a cylinder case 1012. The cylinder case 1012 has a cylindrical portion 1012a forming a cylinder 1031 and a head 1012b. The piston 1032 forms a combustion chamber 1005 together with the cylindrical portion 1012a and the head 1012b.

The fuel combustion mechanism 1070 includes an intake passage for sucking air into the combustion chamber 1005 from the outside, an exhaust passage for discharging exhaust gas from the combustion chamber 1005 to the outside, and a switching mechanism 1080 for switching between intake and exhaust. have. The configuration of the fuel combustion mechanism 1070 is the same as that in the fourth embodiment, so detailed explanation will be omitted.

[Reciprocating rotation conversion mechanism]
Next, the reciprocating rotation conversion mechanism 1030 will be described in detail. The rotating member 1033 is arranged coaxially and rotatably around the piston 1032. The conversion mechanism 1050 has a first wavy groove 1051 and a second wavy groove 2051 formed on the rotating member 1033, and a first roller part 1052 and a second roller part 2052 formed on the piston 1032 (see FIG. (see 7). The first waveform groove 1051 and the second waveform groove 2051 have a waveform that is alternately displaced in the axial direction D1 over the entire circumference of the rotating member 1033 in the rotational direction.

On the downward Dd side in the axial direction D1 of the piston 1032 on the upward Du side, there is a rotatable shaft-shaped first roller part 1052 that protrudes to one side in the radial direction D2, and the first roller part 1052 is connected to the piston 1032. A pair of bearings 1053 are provided to support the bearings rotatably around the radial direction D2. That is, on both sides of the piston 1032 in the radial direction D2, the distal ends of the separate first roller parts 1052 protrude radially inward, and are respectively fitted into the first corrugated grooves 1051 and guided.

On the upper Du side of the axial direction D1 of the piston 1032 on the lower Dd side, there is a rotatable shaft-shaped second roller part 2052 that protrudes to one side in the radial direction D2, and the second roller part 2052 is connected to the piston 1032. A pair of bearings 2053 are provided to support the bearings rotatably around the radial direction D2. That is, on both sides of the piston 1032 in the radial direction D2, the distal ends of the separate second roller parts 2052 protrude radially inward, and are respectively fitted into and guided by the second corrugated grooves 2051.

Here, the pressing relationship between the corrugated groove and the roller portion will be considered. When the piston 1032 reciprocates, if there is one roller portion and one corrugated groove, the roller portion moves between the opposing first cam surface and second cam surface of the corrugated groove every time the rotating member 1033 rotates 90 degrees. It will then transfer to the opposite cam surface. At this time, the rotational direction of the roller section is reversed, which causes friction. That is, since friction is generated due to the rotational reversal of the roller portion four times during one rotation of the rotating member 1033, there is a possibility that the reduction in friction will be insufficient. Therefore, in this embodiment, a configuration is adopted in which two cam followers are provided so that the roller portion always comes into contact with the cam surface on the same side.

That is, as shown in FIG. 7, the first cam surface 1051a of the first wave groove 1051 faces the downward Dd side (one side) in the axial direction D1 over the entire circumference in the rotational direction. and a second cam surface 2051a of the second wave-shaped groove 1051 facing the upper Du side (the other side) in the axial direction D1 over the entire circumference in the rotational direction. The roller parts 1052, 2052 include a first roller part (first roller) 1052 that is guided by contacting the first cam surface 1051a, and a second roller part (first roller) that is guided by contacting the second cam surface 2051a. (second roller) 2052. Thereby, the first roller part 1052 is guided by contacting only the first cam surface 1051a, and the second roller part 2052 is guided by contacting only the second cam surface 2051a. Note that each cam surface 1051a, 2051a and the outer circumferential surface of the roller portions 1052, 2052 have a slope, but since this is the same as in the fourth embodiment, detailed explanation will be omitted.

The regulating mechanism 1060 includes an axial groove 1061 formed in the piston 1032, a shaft 1063 disposed in the cylinder 1031, and a rolling member 1062 provided in the shaft 1063. The configuration and operation of the regulating mechanism 1060 are the same as those in the fourth embodiment, so a detailed explanation will be omitted.

In this internal combustion engine 1000, the rotating member 1033 rotates as the piston 1032 reciprocates, and a driving force is output from a gear portion 1033a formed on the outer peripheral surface of the rotating member 1033.

As explained above, according to the reciprocating rotation conversion mechanism 1030 of this embodiment, the first roller part 1052 is guided by contacting only the first cam surface 1051a, and the second roller part 2052 is guided only by the second cam surface 2051a. Since the roller portion is guided in contact with the cam surface, the roller portion does not transfer to another cam surface, and the frictional resistance in the conversion mechanism 1050 can be reduced. Therefore, the rotational and reciprocating conversion efficiency can be improved, and the fuel efficiency of the internal combustion engine 1000 can be improved.

<Sixth embodiment>
Next, a sixth embodiment of the present disclosure will be described in detail with reference to FIGS. 8 and 9. In this embodiment, two roller parts 1252, 2252 are arranged in one wave-shaped groove 1251 so as to be shifted in the axial direction D1, so that each roller part 1252, 2252 contacts only one cam surface. The configuration is different from the fifth embodiment. An outline of this internal combustion engine 1200 will be explained using FIG. 8. In this embodiment, internal combustion engine 1200 is a four-stroke engine, and includes a case 1210, a reciprocating rotation conversion mechanism 1230, and a fuel combustion mechanism 1270. In this embodiment, fuel combustion mechanisms 1270 are provided at both ends of one reciprocating rotation conversion mechanism 1230 in the axial direction D1, and combustion chambers 1205 are provided on both sides of one piston 1232. Two such combinations are provided adjacent to each other in the radial direction D2. The reciprocating rotation conversion mechanism 1230 and the fuel combustion mechanism 1270 have the same configuration except that they have different phases.

The reciprocating rotation conversion mechanism 1230 includes a cylinder 1231 fixed to a case 1210, a piston 1232 arranged so as to be reciprocated in the axial direction D1 within the cylinder 1231, a cylindrical rotating member 1233, and the piston 1232 and the rotating member 1233. It has a conversion mechanism 1250 that is interposed between the piston 1232 and converts the reciprocation of the piston 1232 and the rotation of the rotating member 1233, and a restriction mechanism 1260 that restricts the rotation of the piston 1232 with respect to the cylinder 1231. Details of the reciprocating rotation conversion mechanism 1230 will be described later.

The case 1210 includes a case body 1211, a top lid 1213 attached to the upper Du side of the case body 1211 in the axial direction D1, a cylinder case 1212 attached to the upper lid 1213, and a lower side of the case body 1211 in the axial direction D1. It has a lower cover 1214 attached to the Dd side and a cylinder case 1215 attached to the lower cover 1214. The cylinder case 1212 has a cylindrical portion 1212a forming a cylinder 1231 and a head 1212b. Cylinder case 1215 has a similar configuration to cylinder case 1212. The piston 1232 forms a combustion chamber 1205 together with the cylindrical portion 1212a and the head 1212b.

The fuel combustion mechanism 1270 includes an intake passage for sucking air into the combustion chamber 1205 from the outside, an exhaust passage for discharging exhaust gas from the combustion chamber 1205 to the outside, and a switching mechanism 1280 for switching between intake and exhaust. have. The configuration of the fuel combustion mechanism 1270 is the same as that in the fourth embodiment, so detailed explanation will be omitted.

[Reciprocating rotation conversion mechanism]
Next, the reciprocating rotation conversion mechanism 1230 will be described in detail. The rotating member 1233 is arranged coaxially and rotatably around the piston 1232. The conversion mechanism 1250 has a wave-shaped groove 1251 formed in a rotating member 1233, and a first roller part 1252 and a second roller part 2252 formed in a piston 1232 (see FIG. 9). The wave-shaped groove 1251 has a wave shape that is alternately displaced in the axial direction D1 over the entire circumference of the rotating member 1233 in the rotation direction.

At the center of the piston 1232 in the axial direction D1, there is a rotatable shaft-shaped first roller part 1252 that protrudes to one side in the radial direction D2, and the first roller part 1252 is connected to the piston 1232 around the radial direction D2. A pair of bearings 1253 are provided to rotatably support. That is, on both sides of the piston 1232 in the radial direction D2, the distal ends of the separate first roller parts 1252 protrude radially inward, and are respectively fitted into the corrugated grooves 1251 and guided.

A rotatable shaft-shaped second roller part 2252 is arranged on the downward Dd side of the first roller part 1252 and protrudes to one side in the radial direction D2. A pair of bearings 2253 are provided at the center for rotatable support. That is, on both sides of the piston 1032 in the radial direction D2, the distal ends of the separate second roller parts 2252 protrude radially inward, and are respectively fitted into the wave-shaped grooves 1251 and guided.

As shown in FIG. 9, the wave-shaped groove 1251 has a first cam surface 1251a facing the downward Dd side (one side) in the axial direction D1 over the entire circumference in the rotation direction, and a first cam surface 1251a facing the downward Dd side (one side) in the axial direction D1 over the entire circumference in the rotation direction. The second cam surface 1251b faces the upper Du side (the other side) in the axial direction D1. The roller parts 1252, 2252 include a first roller part (first roller) 1252 that is guided by contacting the first cam surface 1251a, and a second roller part (first roller) that is guided by contacting the second cam surface 1251b. (second roller) 2252. As a result, the first roller portion 1252 is guided by contacting only the first cam surface 1251a, and the second roller portion 2252 is guided by contacting only the second cam surface 1251b, so that the roller portion is guided by contacting only the second cam surface 1251b. The frictional resistance can be reduced. Note that each cam surface 1051a, 2051a and the outer circumferential surface of the roller portions 1052, 2052 have a slope, but since this is the same as in the fourth embodiment, detailed explanation will be omitted.

The regulating mechanism 1260 includes an axial groove 1261 formed in the piston 1232, a shaft 1263 disposed in the cylinder 1231, and a rolling member 1262 provided in the shaft 1263. The configuration and operation of the regulating mechanism 1260 are the same as those in the fourth embodiment, so detailed explanation will be omitted.

In this internal combustion engine 1000, the rotating member 1233 rotates as the piston 1232 reciprocates, and the gear portions 1233a formed on the outer peripheral surface of the rotating member 1233 mesh with each other and synchronize. Further, an output shaft 1201 is drivingly connected to a gear portion 1233a of one rotating member 1233 via a gear portion 1201a. Driving force is output from this output shaft 1201.

As explained above, according to the reciprocating rotation conversion mechanism 1230 of this embodiment, the first roller part 1252 is guided by contacting only the first cam surface 1251a, and the second roller part 2252 is guided only by the second cam surface 1251b. Since the roller portion is guided in contact with the cam surface, the roller portion does not transfer to another cam surface, and the frictional resistance in the conversion mechanism 1250 can be reduced. Therefore, the rotational and reciprocating conversion efficiency can be improved, and the fuel efficiency of the internal combustion engine 1200 can be improved.

In the fourth to sixth embodiments described above, in the regulating mechanism 760, 1060, 1260, the rolling member 762, 1062, 1262 is provided between the shaft 763, 1063, 1263 and the axial groove 761, 1061, 1262. Although a case has been described in which the rolling members 762, 1062, and 1262 are provided, the present invention is not limited to this, and for example, the rolling members 762, 1062, and 1262 may not be provided. In this case, although the frictional resistance between the shafts 763, 1063, 1263 and the axial grooves 761, 1061, 1261 increases, the number of parts can be reduced. Further, in the fourth to sixth embodiments described above, the cam surface of the wave-shaped groove and the outer circumferential surface of the roller part have been described as having a slope, but the present invention is not limited to this. Good too.

100,200,300...Electric pump, 130,230,330,730,1030,1230...Reciprocating rotation conversion mechanism, 131,231,331,731,1031,1231...Cylinder, 132,232,332,732,1032, 1232...Piston, 133,233,333,733,1033,1233...Rotating member, 140...Pump section, 150,250,350,750,1050,1250...Conversion mechanism, 151,251,351,751,1051,1251 , 2051... Wave-shaped groove, 152, 252, 352, 752, 1052, 1252, 2052, 2252... Roller portion, 153... Shaft member (shaft), 160, 260, 360, 760, 1060, 1260... Regulation mechanism, 161, 261,361,761,1061,1261...Axial groove, 162,262,362,762,1062,1262...Rolling member, 251a, 351a, 751a, 1051a, 1251a...First cam surface, 251b, 351b, 751b , 1251b, 2051a...Second cam surface, 252a, 352a, 752a...Outer peripheral surface, 263...Shaft, 700, 1000, 1200...Internal combustion engine, 701...First output shaft (output shaft), 702...Second output shaft ( 770, 1070, 1270... Fuel combustion mechanism, 1052, 1252... First roller part (first roller), 1202... Output shaft, 2052, 2252... Second roller part (second roller), D1... Axis Direction, D2...radial direction

Claims (8)

cylinder and
a piston arranged to be able to reciprocate in the axial direction within the cylinder;
a rotating member coaxially rotatably disposed around the piston;
a conversion mechanism that is interposed between the piston and the rotating member and converts reciprocation of the piston and rotation of the rotating member, the conversion mechanism being disposed on one of the piston and the rotating member; a wavy groove having a wavy shape alternately displaced in the axial direction over the entire circumference in the rotational direction; and a wavy groove that is disposed on the other of the piston and the rotating member and is guided by being fitted into the wavy groove. a conversion mechanism having a roller section;
a regulating mechanism that regulates rotation of the piston relative to the cylinder;
The regulatory mechanism is
an axial groove disposed in one of the cylinder and the piston and formed so that the axial direction is the longitudinal direction; and an axial groove disposed in the other of the cylinder and the piston in the axial direction and the rotational direction. a shaft arranged to restrict relative movement and guided in the axial direction by the axial groove; and a rolling member arranged to be interposed between the axial groove and the shaft. , has
Reciprocating rotation conversion mechanism. The wave-shaped groove includes a first cam surface facing one side in the axial direction over the entire circumference in the rotation direction, and a second cam surface facing the other side in the axial direction over the entire circumference in the rotation direction. having a surface;
The roller portion includes a first roller that is guided in contact with the first cam surface, and a second roller that is guided in contact with the second cam surface.
The reciprocating rotation conversion mechanism according to claim 1. The wave-shaped groove includes a first cam surface facing one side in the axial direction over the entire circumference in the rotation direction, and a second cam surface facing the other side in the axial direction over the entire circumference in the rotation direction. having a surface;
The first cam surface has a slope such that the outer diameter side in the radial direction of the piston is farther from the second cam surface than the inner diameter side,
The second cam surface has a slope such that the outer diameter side in the radial direction is farther from the first cam surface than the inner diameter side,
The roller portion has an outer circumferential surface having a slope such that the outer diameter side in the radial direction has a larger diameter than the inner diameter side.
The reciprocating rotation conversion mechanism according to claim 1 or 2. cylinder and
a piston arranged to be able to reciprocate in the axial direction within the cylinder;
a rotating member coaxially rotatably disposed around the piston;
a conversion mechanism that is interposed between the piston and the rotating member and converts reciprocation of the piston and rotation of the rotating member, the conversion mechanism being disposed on one of the piston and the rotating member; a wavy groove having a wavy shape alternately displaced in the axial direction over the entire circumference in the rotational direction; and a wavy groove that is disposed on the other of the piston and the rotating member and is guided by being fitted into the wavy groove. a conversion mechanism having a roller section;
a regulating mechanism that regulates rotation of the piston relative to the cylinder;
The wave-shaped groove includes a first cam surface facing one side in the axial direction over the entire circumference in the rotation direction, and a second cam surface facing the other side in the axial direction over the entire circumference in the rotation direction. having a surface;
The roller portion includes a first roller that is guided in contact with the first cam surface, and a second roller that is guided in contact with the second cam surface.
Reciprocating rotation conversion mechanism. cylinder and
a piston arranged to be able to reciprocate in the axial direction within the cylinder;
a rotating member coaxially rotatably disposed around the piston;
a conversion mechanism that is interposed between the piston and the rotating member and converts reciprocation of the piston and rotation of the rotating member, the conversion mechanism being disposed on one of the piston and the rotating member; a wavy groove having a wavy shape alternately displaced in the axial direction over the entire circumference in the rotational direction; and a wavy groove that is disposed on the other of the piston and the rotating member and is guided by being fitted into the wavy groove. a conversion mechanism having a roller section;
a regulating mechanism that regulates rotation of the piston relative to the cylinder;
The wave-shaped groove includes a first cam surface facing one side in the axial direction over the entire circumference in the rotation direction, and a second cam surface facing the other side in the axial direction over the entire circumference in the rotation direction. having a surface;
The first cam surface has a slope such that the outer diameter side in the radial direction of the piston is farther from the second cam surface than the inner diameter side,
The second cam surface has a slope such that the outer diameter side in the radial direction is farther from the first cam surface than the inner diameter side,
The roller portion has an outer circumferential surface having a slope such that the outer diameter side in the radial direction has a larger diameter than the inner diameter side.
Reciprocating rotation conversion mechanism. The first cam surface, the second cam surface, and the outer circumferential surface of the roller portion are such that the roller portion contacts the first cam surface and the second cam surface at a portion along the rotation direction in the wave-shaped groove. On the other hand, it has a slope angle smaller than the slope angle that does not cause slippage on the outer diameter side and inner diameter side.
The reciprocating rotation conversion mechanism according to claim 5. A reciprocating rotation conversion mechanism according to any one of claims 1 to 6,
a pump unit that sucks fluid through reciprocating motion of the piston, pressurizes it, and discharges it;
The rotating member rotates integrally with the rotor of the electric motor.
electric pump. A reciprocating rotation conversion mechanism according to any one of claims 1 to 6,
a fuel combustion mechanism that presses the piston to obtain output by burning fuel in the cylinder;
The rotating member is an output shaft that outputs driving force to the outside,
internal combustion engine.

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