JP2960296B2 - Rotational motion-linear reciprocating motion conversion device and hydraulic pressure generating device using this device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotary motion-linear reciprocating motion converting device capable of converting a rotary motion into a linear reciprocating motion or a linear reciprocating motion into a rotary motion, and a pulsation using the device. The present invention relates to a hydraulic pressure generator that can be minimized.

[0002]

2. Description of the Related Art A conventional hydraulic pressure generating device is an engine similar to a slider crank mechanism, and pumps a pump such as a swash plate type pump or an injection type pump capable of converting rotary motion into linear motion, and pumps oil in a hydraulic tank. It consisted of actuators such as cylinders and motors, control valves for controlling the actuators, and other auxiliary devices that played an auxiliary role. Since such a hydraulic pressure generator is used at a high pressure,
Positive displacement pumps were suitable, and generally vane, gear or plunger types were often used. In addition, under special use conditions such as large capacity or high viscosity, a screw pump has been used.

[0003]

However, in the conventional hydraulic generator described above, since the swash plate type pump and the injection type pump are engines similar to the slider crank mechanism, a linear motion is required in the process of converting the rotary motion into the linear motion. The motion displacement, speed, and acceleration of the motion portion perform a wavy motion according to the rotation amount θ of the crank, causing a problem that a pulsation phenomenon occurs in the discharge oil amount and the pressure. In addition, such a pulsation phenomenon causes a variation in hydraulic pressure, and there is a problem that even an operation of an actuator varies in an automated system.

[0004] The pulsation phenomenon can be prevented by providing a pressure accumulator and other auxiliary equipment in the hydraulic pressure generating device. However, in such a configuration, control means such as the pressure accumulator must be separately provided. However, there is a problem that the configuration of the hydraulic pressure generating device is complicated.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has a simple structure capable of minimizing the generation of pulsation and obtaining a uniform hydraulic pressure. And a hydraulic pressure generating device using the device.

[0006]

SUMMARY OF THE INVENTION In order to solve the above problems, a rotary motion-linear reciprocating motion converter according to the present invention of claim 1 has a power transmission portion formed at least partially in a circumferential direction . Rotational drive having a power transmission element 4 and a second power transmission element 5 having a power transmission portion formed only at a portion corresponding to a circumferential portion of the first power transmission element 4 not forming a power transmission portion. Part 2, the first and second power transmission elements 4, 5 and the third and fourth power transmission elements 6, which are rotatable by being directly or indirectly connected to each other via the power transmission part .
7 and a linear motion part 3 having a spiral shaft 8 in which spiral grooves 9, 10 in which the third and fourth power transmission elements 6, 7 are independently engaged are formed in opposite directions.
The linear motion of the helical shaft 8 is used as the rotary motion of the first and second power transmission elements 4 and 5, or the rotary motion of the first and second power transmission elements 4 and 5 is used as the linear motion of the helical shaft 8 It is configured to be converted to.

Further, in the rotary motion-linear reciprocating motion converter according to the present invention, the first and second power transmission elements 4 and 5 are constituted by toothless gears in which a gear is formed in the power transmission portion. The third and fourth power transmission elements 6, 7 are constituted by gears.

Further, in the rotary motion-linear reciprocating motion converter according to the present invention, the first and second power transmission elements 4 and 5 are constituted by a friction wheel in which a friction surface is formed on the power transmission portion. The third and fourth power transmission elements 6, 7 are constituted by friction wheels.

According to a fourth aspect of the present invention, there is provided a hydraulic pressure generating device including cylinders 27 and 28 and pistons 25 and 26 located in the cylinders 27 and 28 and attached to the shaft ends of the helical shaft 8, respectively. The oil is continuously pumped by the linear reciprocating motion of the spiral shaft 8.

[0010]

According to the rotary motion-linear reciprocating motion converter of the present invention having the above-described structure, the power from the rotary drive unit or the linear motion unit is transmitted from two places by the power transmission elements 4, 5, 6, and 7. It is alternately and continuously transmitted to a linear motion unit or a rotary drive unit. For example, when a rotational force is applied from the rotation drive unit, the power transmission elements 4 and 5 rotate at the same speed, and alternately and continuously transmit the rotational force to the linear motion unit. Thus, in the linear motion section, the spiral shaft 8 continuously linearly reciprocates.

Further, according to the hydraulic pressure generator of the present invention using the above-mentioned rotary motion / linear reciprocating motion converter, the pistons 25 and 26 move the cylinders 2 by the reciprocating linear motion of the helical shaft 8.
7 and 28 to pump the oil in the hydraulic tanks 29 and 30.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a rotary motion-linear reciprocating motion converter of the present invention and a hydraulic pressure generator using the device will be described below with reference to the drawings. First, an embodiment of the rotary motion-linear reciprocating motion converter of the present invention will be described.
FIG. 1 is a perspective view showing a rotary motion / linear reciprocating motion converter according to the present embodiment. In the rotary motion-linear reciprocating motion converter of the present embodiment, the power transmission element on the rotary drive unit side is constituted by two missing gears, and the power transmission element on the linear motion unit side is engaged with these missing gears. It consists of two gears.

In FIG. 1, the present rotary motion-linear reciprocating motion converter mainly includes a driving means 1 such as a hydraulic motor.
And a rotary drive unit 2 that rotates by the driving force of the drive unit 1 and a linear motion unit 3 that converts the rotary motion of the rotary drive unit 2 into a linear motion. The rotation drive unit 2 includes first and second toothless gears 4 and 5 attached to a shaft of the drive unit 1.
Has teeth 13 only in a portion corresponding to one half of its circumferential surface,
14 are formed. The second partially toothed gear 5 is attached to the shaft so that the teeth 14 of the first partially toothed gear 4 correspond to the portions of the first partially toothed gear 4 where the teeth 13 are not formed.

The linear motion section 3 includes gears 6 and 7 and a helical shaft 8. The gears 6 and 7 mesh with the first and second missing tooth gears 4 and 5, and the first and second missing gears 4 and 5 engage with each other.
It rotates under the torque of 5. Further, through holes are provided in the center portions of the gears 6 and 7, respectively, and the helical shaft 8 is made to pass through these through holes. Such a spiral shaft 8
Are connected so as to be linearly movable by rotation of the gears 6 and 7. In other words, in this embodiment, a clockwise spiral groove 9 is formed on one side of the spiral shaft 8 and a counterclockwise spiral groove 10 is formed on the other side. Are formed on the inner surface of the through hole. The projections 11 and 12 are respectively engaged with the spiral grooves 9 and 10.

The rotary drive unit 2 is not limited to the first and second tooth-missing gears 4 and 5, but may be provided with a friction clutch or a rubber pad on a portion corresponding to a half of the circumferential surface to form a friction surface. It may be a formed friction wheel. In this case, in the linear motion section 3, a friction wheel is used instead of the gears 6 and 7.

With such a configuration, the teeth 13 and 14 of the first and second missing gears 4 and 5 alternately mesh with the gears 6 and 7, and each of the first and second missing gears 4 and 5 has The torque is transmitted to the spiral shaft 8 alternately. Since the spiral grooves 9 and 10 of the spiral shaft 8 are formed in directions opposite to each other, the spiral shaft 8 receiving the rotational force from the first and second missing gears 4 and 5 is fixed on both sides in the longitudinal direction. Make a fast reciprocating linear motion.

Here, the helical shaft 8 can be rotated by directly receiving the rotational force of the gears 6 and 7, but if the helical shaft 8 rotates together with the gears 6 and 7, linear movement cannot be performed. Therefore, in this embodiment, the guide plates 15 and 16 for suppressing the rotation of the spiral shaft 8 are fixed to the spiral shaft 8, and the guides 17 and 18 for linearly moving the guide plates 15 and 16 are provided. There is a configuration. These guide plates 15 and 16 are used for the guide 1
It moves while being guided by guide grooves 19 and 20 formed in 7,18.

A key groove is formed in the spiral shaft 8 without using the guide plates 15 and 16, and keys are provided in the frames 23 and 24 holding the spiral shaft 8, and the keys are engaged with the key grooves. Thus, the rotation of the spiral shaft 8 can be suppressed.

The guides 17 and 18 are integrally formed with stoppers 21 and 22 for preventing the gears 6 and 7 from moving together with the linear movement of the spiral shaft 8. Further, spacers S are provided between the gears 6 and 7 so that the gear 6 does not enter the spiral groove 10 and the gear 7 does not enter the spiral groove 9.

Next, an embodiment of the hydraulic pressure generating device of the present invention using the rotary motion / linear reciprocating motion converting device having the above configuration will be described with reference to the drawings. First, a hydraulic pressure generating device according to a first embodiment will be described. FIG. 2 is a perspective view illustrating the hydraulic pressure generating device according to the present embodiment. FIG. 3 is a perspective view showing the meshing state between the first and second missing toothed gears and the gears of the present hydraulic pressure generating device. FIG. 4 is a perspective view showing a helical shaft of the present hydraulic pressure generating device.

In FIG. 2, the present hydraulic pressure generating apparatus has pistons 25 and 26 attached to both ends of a helical shaft 8 and a cylinder 2 for accommodating the pistons 25 and 26, respectively.
7, 28 are fixed to a frame (not shown). With such a configuration, the pistons 25 and 26 move linearly in the cylinders 27 and 28 together with the helical shaft 8.

FIGS. 5A and 5B are diagrams for explaining the hydraulic pressure generating operation of the present hydraulic pressure generating device. FIG. 5A is a configuration diagram, and FIG. 5B is a hydraulic pressure generation timing diagram. FIG.
In (a), cylinders 27 and 28 are connected to fluid storage tanks 29 and 29 via check valves 31 and 32, respectively.
30 is connected. In addition, these cylinders 27 and 2
8 is connected by one hydraulic line 33 and can supply oil along an output line 34. Check valves 35 and 36 are provided between the hydraulic line 33 and the cylinders 27 and 28, respectively. These check valves 35 and 36 are installed in opposite directions to the check valves 31 and 32 so that the hydraulic pressure flowing out of the cylinders 27 and 28 does not flow back into the cylinders 27 and 28.

Next, the operation of the present hydraulic pressure generator having the above configuration will be described. When the driving means 1 is driven, the first and second missing gears 4 and 5 provided on the shaft rotate. The first and second missing toothed gears 4 and 5 are 1/1 of the circumferential surface.
2, only the portion corresponding to No. 2 has teeth, so that the rotational force of these first and second missing gears is alternately changed by the gears 6, 7
Is transmitted to As described above, the rotational force is alternately transmitted to the gears 6 and 7. First, when the rotational force is transmitted to the gear 6, the gears 6 and 7 rotate in the opposite direction to the first toothless gear 4. However, since the movement of the gear 6 is restricted by the stopper 21, the gear 6 rotates at a fixed position. A helical shaft 8 having a helical groove 9 with which the projection 11 of the gear 6 engages
Moves in the axial direction, but since the spiral groove 9 is formed clockwise, the spiral shaft 8 moves to the right in the figure. Then, when the meshing between the first missing gear 4 and the gear 6 is released, the second missing gear 5 comes to mesh with the gear 7, the rotation of the gear 6 is stopped, and the gear 7 starts rotating. .

The rotation of the gear 7 causes the spiral shaft 8 to move, but the spiral groove 10 with which the projection 12 of the gear 7 engages is formed in the opposite direction to the spiral groove 9. The helical shaft 8 moves to the left in the figure. When the spiral shaft 8 moves to the right or left, the guide plates 15 and 16 move horizontally along the groove portions formed in the guides 17 and 18, so that the rotation of the spiral shaft 8 is prevented. In this manner, the movement of the spiral shaft 8 to the right or left is continuously repeated as long as the driving means 1 operates, so that the piston 2 fixed to the tip of the spiral shaft 8 is moved.
The cylinders 5 and 26 reciprocate at a constant speed in the cylinders 27 and 28. When the oil in the cylinders 27, 28 is pumped, the oil in the fluid storage tanks 29, 30 is pumped through the hydraulic line 33 and flows along the output line 34 into the required equipment.

At this time, as shown in FIG. 5B, the timing of the oil pumped into the cylinder 27 located on the right side and the timing of the oil pumped into the cylinder 28 located on the left side are alternately continuous. So
The pressure of the oil flowing through the output line 34 becomes almost uniform, and the pulsation phenomenon does not occur.

Here, a flow rate equation that appears while the rotary drive unit proceeds in the first half cycle is as follows: Q1 = ωp · ρ / 2 · A, and one reciprocating motion per one rotation of the rotary drive unit. In some cases, since 2 · Np / Nm = ρ / S, the rotation speed of the rotation drive unit is as follows: ωp = ωm · Nm / 2 · Np. Therefore, Q1 = ωm · Nm / (2 · Np) · ρ / 2π · A.

Here, ωp is the rotation speed of the gear, ρ is the pitch of the helical shaft, A is the area of the piston, Np is the number of gear teeth,
Nm is the number of teeth of the toothless gear, S is the pump stroke of the piston, ω
m is the rotation speed of the rotation drive unit. Similarly, the flow rate equation during which the rotation drive unit proceeds for a half cycle is as follows: Q2 = ωm · Nm / (2 · Np) · ρ / 2π · A

Here, the total flow rate through the output line becomes Qt = Q1 + Q2, and the flow rate appears as shown in FIG.

Therefore, since the rotation speed of the rotary drive unit is proportional to or the same as the rotation speed of the drive unit, it is considered that the output flow rate is constant when the rotation speed of the drive unit is fixed. When one set of piston pumps makes one reciprocating motion when the rotary drive unit makes one rotation, the flow rate equation is Q1 + Q2. When one set of piston pumps makes two reciprocating motions when the rotation drive unit makes one rotation, Np / Nm = 1/4
, The gears become one set, and the number of divisions becomes four. Further, it is also possible to design a device in which two sets of piston pumps make one reciprocating motion when the rotary drive unit makes one rotation, but this is the same as a case in which one set of piston pumps makes one reciprocating motion. When two sets of piston pumps reciprocate １ ／ when the section makes one rotation, Np / Nm = 1 /
It becomes 2. In this way, it is possible to install a large number of sets of piston pumps in this manner.

Next, a second embodiment of the hydraulic pressure generator of the present invention will be described with reference to FIGS. FIG.
FIG. 2 is a partial cross-sectional perspective view illustrating a hydraulic pressure generating device according to the present embodiment. FIG. 8 is a perspective view of a spiral shaft used in the present hydraulic pressure generating device. In the hydraulic pressure generating device of the present embodiment, one set of piston pumps is configured to reciprocate two times.

In FIG. 7, the first and second missing toothed gears 4,
5 is 1/4 of the circumference at equal intervals in two places on the circumference.
Is formed. In FIG. 8, spiral grooves 9, 10 formed in opposite directions to each other are extended from the left end to the right end of the spiral shaft 8 in the spiral shaft 8. Further, the first and second missing gears 4, 5 are brought into close contact with each other, and the gears 6, 7 are brought into close contact with each other. According to such a configuration, the range in which the gears 6 and 7 can move from the left to the right or from the right to the left can be increased, and further, it is not necessary to provide a spacer between the gears 6 and 7. The device can be made compact.

Next, a third embodiment of the hydraulic pressure generator of the present invention will be described with reference to FIG. FIG. 9 is a perspective view illustrating the hydraulic pressure generating device according to the present embodiment. The hydraulic pressure generating device of the present embodiment has a configuration in which two sets of piston pumps reciprocate two times. In the figure, two spiral shafts 80, 8
Cylinders 27 and 28 are provided on both sides of the cylinder 1, respectively. Pistons reciprocating in the cylinders 27 and 28 are provided on both ends of the spiral shafts 80 and 81, respectively. According to such a configuration, the operation is performed in the same manner as in the above-described embodiment, and furthermore, the hydraulic pressure is generated in the four cylinders, so that the hydraulic pressure generation cycle is further shortened and the pulsation of the hydraulic pressure can be minimized. Play.

Next, a fourth embodiment of the hydraulic pressure generator of the present invention will be described with reference to FIG. FIG. 10 is a perspective view illustrating the hydraulic pressure generating device according to the present embodiment. The hydraulic pressure generating device of the present embodiment is configured to include three sets of piston pumps. In the figure, three spiral shafts 8, 8, 8
, Cylinders 27 and 28 are provided on the left and right sides, respectively, so that the respective cylinders 27 and 28 individually perform a pumping action. According to this configuration, at least six or more pumping operations can be performed when the rotation drive unit makes one rotation, and the pulsation of the hydraulic pressure can be further reduced.

According to the rotary motion-linear reciprocating motion conversion device of this embodiment having the above-described configuration and the hydraulic pressure generating device using the device, the timing of the oil pumped in the cylinder 27 located on the right side, Since the timing of the oil pumped in the cylinder 28 located on the left side is alternately continuous, the pressure of the oil flowing through the output line 34 becomes almost uniform, and pulsation can be minimized.

It should be noted that the rotary motion-linear reciprocating motion conversion device of the present invention and the hydraulic pressure generating device using this device are not limited to the above embodiment. For example, in this embodiment, a hydraulic pump type hydraulic pressure generating device has been described. However, this rotary motion-linear reciprocating motion conversion device can also be used for a hydraulic motor capable of obtaining a rotational force using a linear motion of a piston. is there. In this embodiment, the first and second toothless gears (friction wheels) 4, 5 and the gears (friction wheels) 6, 7 are directly meshed with each other. However, this is not particularly limited.
The rotational force of the first and second missing toothed gears (friction wheels) 4, 5 is transmitted by a chain or belt to the gears (friction wheels) 6, 7
It is good also as a structure to tell.

[0036]

As described above, according to the rotary motion / linear reciprocating motion converting apparatus of the present invention, the rotary motion can be converted into a continuous linear reciprocating motion. According to the hydraulic pressure generator of the present invention using such a rotary motion / linear reciprocating motion converter, the initial time and the completion time of the oil pumped by the respective cylinders and pistons provided at both ends of the helical shaft. Can be eliminated, and the pulsation of the hydraulic pressure can be minimized.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a rotary motion-linear reciprocating motion converter according to an embodiment of the present invention.

FIG. 2 is a partial sectional perspective view showing a hydraulic pressure generating device according to the first embodiment of the present invention.

FIG. 3 is a perspective view showing a meshing state of first and second toothless gears and gears of the hydraulic pressure generating device.

FIG. 4 is a perspective view showing a spiral shaft of the hydraulic pressure generating device.

FIGS. 5A and 5B are diagrams for explaining a hydraulic pressure generating operation of the hydraulic pressure generating device, wherein FIG. 5A is a configuration diagram and FIG. 5B is a hydraulic pressure generation timing diagram.

FIG. 6 is an explanatory diagram showing a flow rate of the hydraulic pressure generating device of the present invention.

FIG. 7 is a perspective view showing a hydraulic pressure generating device according to a second embodiment of the present invention.

FIG. 8 is a perspective view showing a spiral shaft of the hydraulic pressure generating device.

FIG. 9 is a perspective view showing a hydraulic pressure generating device according to a third embodiment of the present invention.

FIG. 10 is a perspective view showing a hydraulic pressure generating device according to a fourth embodiment of the present invention.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 drive means 4 first power transmission element (first missing gear) 5 second power transmission element (second missing gear) 6 third power transmission element (gear) 7 fourth power transmission element (gear) 8 helical shaft 9,10 Spiral groove 11,12 Projection 15,16 Guide plate 25,26 Piston 27,28 Cylinder 29,30 Hydraulic tank 33 Hydraulic line 34 Output line

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) F16H 35/00 F16H 25/24 F16H 27/08

Claims (4)

(57) [Claims] And 1. A first power transmission element 4 forming a power transmission unit to at least a portion of the circumferential direction, and the first power transmission element circumferential portion not forming a power transmission part 4 corresponding A rotary drive section 2 having a second power transmission element 5 having a power transmission section only in a portion to be driven, the first and second power transmission elements 4 and 5, and the power transmission section
And third and fourth power transmitting elements 6, 7 rotatable directly or indirectly connected respectively through these third and
Consists linear movement portion 3 and having a helical axis 8 formed with helical grooves 9 and 10 four power transmission elements 6, 7 are engaged each independently engaged in the opposite directions, the linear movement of the spiral shaft 8 Converting the rotational movement of the first and second power transmission elements 4 and 5 or the rotational movement of the first and second power transmission elements 4 and 5 into the linear movement of the spiral shaft 8; Characteristic rotary motion-linear reciprocating motion conversion device. 2. The first and second power transmission elements 4, 5 are constituted by toothless gears having gears formed in the power transmission section, and the third and fourth power transmission elements 6, 7 are constituted by gears. 2. A rotary motion-linear reciprocating motion converter according to claim 1. 3. The first and second power transmission elements 4, 5 are constituted by friction wheels having friction surfaces formed on the power transmission portion, and the third and fourth power transmission elements 6, 7 are constituted by friction wheels. 3. The rotary motion-linear reciprocating motion converter according to claim 2, wherein the conversion device comprises: 4. A hydraulic pressure generating device using the rotary motion / linear reciprocating motion converter according to claim 1, wherein the hydraulic pressure generating device is located in the cylinders 27 and 28. And a piston 25, 26 attached to the end of the helical shaft 8, respectively, and continuously pumps oil by the linear reciprocating motion of the helical shaft 8.