JPS611833A - Rotary-movement transmitting apparatus - Google Patents

Abstract

PURPOSE:To reduce the dimension of a fuel injection timing controller by varying the relative revolution angle between a housing revolved in synchronization with a driving shaft and the swing vanes on an output shaft which are accommodated into the housing by an oil pressure. CONSTITUTION:The fixed vanes 64a and 64b having a fan-shaped section are arranged into the cylindrical bore 60 of an actuator housing 56 revolved in synchronization with a driving shaft, and the swing vanes 62a and 62b formed integrally onto an output shaft 36 integrally formed with a driven shaft are arranged into two operation chambers 66a and 66b. The fuel injection timing is varied by varying the relative revolution angle position between the actuator housing 56 and the swing vanes 62a and 62b through the inflow of the pressurized working oil into the operation chambers 66a and 66b. Thus, the dimension of the fuel injection timing controller can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a rotary motion for transmitting the rotational motion of a drive shaft to a driven shaft while making the relative rotational angular position between the drive shaft and the driven shaft variable. It relates to a transmission device.

The above-mentioned rotational motion transmission device is a variable injection type that is arranged between the input shaft of a fuel injection pump of a diesel engine and a drive shaft that rotates at the engine crankshaft VcPI period to vary the injection timing according to engine parameters. It can be used as a suspension device, and can be installed between the camshaft that drives the engine's intake and exhaust valves and the drive shaft to change the operating timing of the intake and exhaust valves according to engine parameters. It can also be used as a variable pulp timing device.

Conventional technology A typical rotary motion transmission device that transmits the rotational motion of the drive shaft to the driven shaft while varying the relative rotational angular position between the drive shaft and the driven shaft is the variable timing of a fuel injection pump. Conventionally, there is an automatic timer type device that is equipped with flyweights, springs, etc., and automatically changes the relative angle between the drive shaft and the injection pump input shaft according to the engine speed. There is.

However, in such a variable tie mechanism, the engine parameters used for control are very limited.

Furthermore, a variable timing mechanism has been proposed that uses an eccentric cam and a hydraulic piston to control the relative angle between the drive shaft and the driven shaft (Japanese Utility Model Publication No. 58-18034). The problem is that a large hydraulic piston is required to make this work, and the entire mechanism becomes very large.

Furthermore, a type in which the relative angle between the driving shaft and the driven shaft can be varied by a combination of a hydraulic piston and a helical spline has been proposed (Japanese Utility Model Publication No. 58-2337). In order for the timing mechanism to function stably, a large diameter piston is required.
The disadvantage is that the device becomes extremely large.

Problems to be Solved by the Invention The present invention provides a rotational motion transmission device that transmits rotational motion of a drive shaft to a driven shaft while varying the relative rotational angular position between the drive shaft and the driven shaft. The present invention aims to provide a rotary motion transmission device which is simple and compact, has stable control, and is effective as a variable timing mechanism.

Means for Solving the Problems In order to solve the above problems, the present invention includes a variable timing actuator that controls the relative angular position between a drive shaft and a driven shaft, the actuator controlling the relative angular position of the drive shaft. The actuator housing includes an actuator housing that rotates in synchronization with the actuator housing, and an output shaft that has a swing vane housed in the housing and is connected to the driven shaft, and the swing vane of the output shaft rotates in synchronization with the drive shaft. The oil pressure introduced into the working chamber provided in the housing is supported so that the relative rotation angle position with respect to the housing can be changed, and a defoaming device for separating air bubbles in the hydraulic oil is provided in the oil pressure introduction circuit. A rotary motion transmission device is configured.

Function: In the present invention, the actuator housing rotates in synchronization with the drive shaft, and when no hydraulic pressure is introduced into the housing, the swing vane and the output shaft also rotate in the same direction as the actuator housing, and the actuator housing at this time rotates in the same direction as the actuator housing. The relative rotation angle position of the output shaft with respect to the housing becomes the rearmost reference position.

The driven shaft is therefore rotated synchronously with the actuator housing.

When hydraulic pressure is introduced into the working chamber in the actuator housing, the swinging vane rotates in the forward direction of rotation relative to the hydraulic pressure actuator housing. Therefore, the output shaft advances relative to the actuator housing, thereby advancing the drive of the driven shaft connected thereto. When the hydraulic pressure in the working chamber is discharged, the swinging bay 7 returns to the lagging side in the rotational direction with respect to the actuator housing,
Therefore, the drive of the driven shaft is delayed. By controlling the hydraulic pressure introduced into the working chamber in this manner, the advance angle of the drive of the driven shaft can be freely controlled.

When introducing the above hydraulic pressure, the hydraulic oil is passed through a defoaming device)
Since the air bubbles are separated, the hydraulic oil is not affected by air bubbles and acts as an incompressible fluid, and stable and strong torque can be obtained even during advance angle control of the driven shaft. The operation of the equipment will be stable.

Embodiments Examples of the present invention will be described below with reference to the drawings.

FIG. 1 shows the application of the present invention as a variable timing mechanism for a fuel injection pump 200 for a diesel engine.

The rotational motion transmission device 10 includes a stationary housing 14, and the stationary housing 14 is composed of a rear plate 16 and a front cover 18. The rear plate 16 is provided with a 2° round hole into which the input shaft 202 of the fuel injection pump 200 is inserted. Stationary housing 14
A drive shaft 22 is rotatably supported via roller bearings 24,26. Drive shaft 22 daughter, oil seal 2
It is sealed by 8. A drive gear 3o schematically shown by a broken line is keyed to the drive shaft 22, and this drive gear 3o has teeth 32 formed on the outer periphery of the actuator housing of the swing vane actuator 12 (described later). (see). An output shaft 36 of the device 10 is rotatably supported on the front cover 18 via a roller p-bearing 34. This output shaft 36 constitutes the output shaft of the swing vane type actuator 12, and is a hollow shaft in the illustrated embodiment. An internal thread is provided at the left end of the internal cavity 38 of the output shaft 36 of this hollow shaft, and a threaded plug 4o is screwed into the internal thread.
One end is sealed liquid-tight. A tapered portion 42 is formed on the right side of the internal cavity 38. An input shaft 202 of the injection pump is keyed to this tapered portion 42, and a threaded end of the input shaft 202 is connected to the input shaft 202 through a washer. bag nuts 4
4, the output shaft 36 and input shaft 202 are connected.

The actuator housing 46 of the oscillating vane actuator 12 is rotatably mounted relative to the output shaft 36 by roller bearings 48,50. The actuator housing 46 is composed of a front side plate 52, a rear side plate 54, and a cylinder 56, which are connected to each other by screws 58. A cylindrical bore 60 is formed inside the actuator housing 46 by these front side plate 52, rear side plate 54, and cylinder 56, and this bore 60 is coaxial with the axis of the wire output shaft 36. (
(See Figure 2). As described above, the cylinder 56 has teeth 32 formed on its outer periphery and meshes with the drive gear 30. This cylinder 56 with integrally formed teeth 32 constitutes an input gear of the actuator 12. Therefore, when the drive shaft 22 rotates, the actuator housing 46 is rotationally driven.

In the illustrated embodiment, the swing vane type actuator 12 is a double vane type, and as shown in FIG. 2, two swing vanes 62g and 62b are integrally formed on the output shaft 36. These swing vanes 152a, 62b extend generally radially outward and axially from the output shaft 36, with a slight clearance provided between the swing vanes and the inner wall of the housing 46. This allows the swing vane to swing smoothly inside the housing 46.

As can be seen from FIG. 2, two fixed vanes 64a and 64b each having a female sector-shaped cross section are disposed inside the cylindrical bore 60 of the actuator housing 46. Two working chambers 66a, 66b and two spring chambers 68a* are diametrically opposed to each other between each fixed vane 64 and the swinging vane 62, which extend along the entire length of the cylindrical bore 60. 68 b t- are formed respectively. The rear plate 54 of the housing 46 and the fixed vane 6
4 are joined to each other by four through bolts 70.

, a protrusion 72 constituting a stopper of the swinging vane 62 is provided on the side surface of each of the fixed vanes 64a and 64b on the advancing side in the rotational direction.
a and 72b are provided so that when the swinging table 762 swings clockwise in FIG. It has become.

respective spring chambers 68a;

68b KU coil springs 74a and 74b are provided, one end of these springs is supported by fixed vanes 64g and 64b, and the other end is a spherical spring receiver 76a provided on a swinging vane.#76 It is supported by b.

Therefore, these coil springs 74B, 74b urge the swing vane 62, and hence the output shaft 36, toward the rear side in the rotational direction (clockwise in FIG. 2). Each of the working chambers 66 and spring chambers 68 is constructed to be substantially liquid-tight.

Each working chamber 66a of the swinging burn type actuator 12,
Hydraulic oil is supplied to 66b from the hydraulic pump 204 via the defoaming tank 300. The defoaming tank 300 has a casing 301
A lid member 303 is integrally fixed to the upper end of the housing. The lid member 303 is provided with an oil inflow pipe 306, and the tip of the oil inflow pipe 306 is bent in the horizontal tangential direction of the defoaming chamber 307. Further, the lid member 303 is provided with a drain pipe 304 including an orifice 305 and connected to the discharge pipe 214. A bottom plate 302 is caulked to the lower part of the casing 301, and a supply pipe 308 is provided on the bottom plate 302. For this purpose, a passage 78 is provided in the rear plate 16 of the stationary housing 14, and this passage 78 is connected to a swivel joint 8 fixed to the rear plate 16.
It communicates with the internal passage 82 of 0. This swivel a hand
An output shaft 36 is rotatably inserted through the shaft 9, and an annular passage 84 communicating with the passage 82 is provided on the inner peripheral surface of the swivel joint. The output shaft 36 is provided with a radial communication passage 86 at a position aligned with the annular passage 84, so that even when the output shaft 36 rotates, the hydraulic oil from the pump 204 flows into the internal cavity 38 of the output shaft 36. is about to be introduced. The hydraulic fluid in the internal cavity 38 is supplied to the respective working chambers 66g, 66b via radial communication passages 88a, 88b bored in the output shaft 36.

As shown in FIG. 2, the actuator housing 46
The front side plate 52 has a drain bow) 90a.

90b is formed through the reed so that the hydraulic oil in the spring chamber 68 can be discharged to the outside of the actuator 12. The discharged hydraulic oil is discharged to the outside of the housing 14 through a reservoir in the lower part of the stationary housing 14 and a drain (not shown) provided in the front cover 18.

In order to detect the relative rotational angular position of the output shaft 36 with respect to the actuator housing 46, a first magnetic sensor 92 is attached to the front force /<-18 at a position facing the front side plate 52. For example, 16 pulsers 94 are provided on the front plate 52 at equal intervals in the circumferential direction, facing the magnetic sensor 92. In addition, swivel joint 80
A second magnetic sensor 96 is fixed facing the output shaft 36, and for example, 16 second pulsers 98 are arranged in a circle on the outer periphery of the output shaft 36 at positions facing the second magnetic sensor 96. They are provided at equal intervals in the circumferential direction.

Next, as shown in FIG. 1, the mode of operation will be described when the rotary motion transmission device 10 of the present invention is used as a variable timer mechanism of the injection pump 200.

Signals from magnetic sensors 92,96 are input to an electronic control unit 206 (EOU). ] 130U206 also receives an engine rotational speed signal S1, a signal S2 representing the engine load, that is, the accelerator opening, and signals representing other engine parameters. EOU20
6 calculates the optimal injection timing from these parameters,
As will be described later, the operating chambers 66a and 66b of the swing vane type actuator 12 are controlled by controlling the electromagnetic shutoff valves 20B and 210.
Controls the pressure of hydraulic oil supplied to the

During operation of the engine, the actuator housing 46 is rotationally driven in the direction indicated by arrow R in FIG. 2 by the drive shaft 22 and drive gear 30, which rotate in synchronization with the rotation of the engine crankshaft. ECU206 is electromagnetic cutoff valve 208
When the valve is closed and no hydraulic pressure is supplied to the working chamber 66, the swinging vane 62 is moved to the second position by the coil spring 74.
When it is pushed clockwise in the figure, it comes into contact with a protrusion of the fixed vane 64, that is, a stopper 72. Therefore, the swing page 762 and the output shaft 36 are
6, and the relative rotational angular position of the output shaft 36 with respect to the actuator housing 46 at this time becomes the rearmost reference position. The input shaft 202 of the injection pump, which is connected to the output shaft 36 via the tapered portion 42 , is rotationally driven in synchronization with the actuator housing 46 .

The hydraulic oil sucked from the tank 212 and pressurized by the hydraulic pump 204 flows into the deoiling chamber 307 of the defoaming tank 300 through the oil inlet pipe 306 .

The air bubbles contained in the hydraulic oil that has flowed into the defoaming chamber 307 float to the top of the defoaming chamber 307 while staying there.

Since a drain pipe 304 including an orifice 305 is provided above the defoaming chamber 307, the hydraulic oil containing many air bubbles is discharged through the drain pipe 304. Note that the amount of hydraulic oil flowing out from the orifice 305 of this drain pipe 304 is sufficiently small, so that the oil pressure of the hydraulic oil does not drop significantly. On the other hand, the hydraulic oil from which air bubbles have been separated while staying in the degassing chamber 307 is supplied to the inflow cutoff valve 208 through a supply pipe 308 provided on the bottom plate 302 . Next, B
When the OU 206 opens the inflow side shutoff valve 208, the outflow 1
When the 1 m valve 2l0 is closed, hydraulic oil flows into the internal cavity 38 of the output shaft 36 via the passage 78, the internal passage 82, the annular passage 84, and the radial passage 86. The hydraulic oil that has flowed into the internal cavity 38 flows through a rear direction communication passage 88 provided in the output shaft 36.
The air flows into the respective working chambers 66a, 66b through the passage. The pressurized hydraulic oil acts on the side surface of each swinging bay 762 that faces the working chamber 66 . Since the swinging vane 62 and the actuator housing 46 are configured to be able to rotate at a fixed angle relative to each other, the swinging vane 62 is rotated by the hydraulic pressure in the working chamber against the action of the coil springs 74a and 74b. The pump 12000 Å overcomes the torque driving the force shaft 202 and rotates relative to the actuator housing 46 in the forward direction of rotation (FIG. 3). Like this,
The actuator housing 46 always rotates in synchronization with the engine crankshaft, but since the swing vane 62 and therefore the output shaft 36 are advanced relative to the actuator housing 46, the injection timing of the injection pump 200 is advanced. They will be cornered. In this advance position, the volume of each working chamber 66 increases, and the volume of the spring chamber 68 decreases. The hydraulic oil in each spring chamber 68 is discharged via a drain boat 90.

On the other hand, when delaying the injection timing, the inflow side shutoff valve 2
08 and open the outflow side shutoff valve 210. The swinging vane 62 has an injection pump 12000Å force shaft 202t-
Due to the driving torque and the elastic force of the coil spring 74, the hydraulic pressure in the working chamber 66 is at a high value, so
The hydraulic oil in each working chamber 66 returns to the tank 212 through the hydraulic oil supply passage and the return pipe 214. Therefore, the swing vane and the output shaft 36 rotate clockwise in FIG.
The fuel injection timing will be delayed.

When driving the injection pump with a constant advance timing between the maximum advance timing and the maximum retardation timing, the inflow side cutoff valve 2
If the hydraulic oil is confined in the respective working chambers 66a and 66b by closing both the shutoff valve 210 and the outflow @ shutoff valve 210, the relative rotation between the actuator housing 46 and the swing vane 62, that is, the output shaft 36 is prevented. Since the angular position is fixed to a constant value, the fuel injection timing is also constant. however,
There is a slight clearance between the swing vane 62 and the inner wall of the actuator housing 46, and since hydraulic oil actually leaks through the clearance, both electromagnetic shutoff valves 208 and 210 are closed. If left as is, the fuel injection timing will gradually shift to the retarded side. Therefore, in reality, the electromagnetic quick-release valve 208.2 by BOU 206
10 is preferably controlled as follows. That is, the fourth
The figure shows an output signal A from the first magnetic sensor 92 and an output signal B from the second magnetic sensor 96. The storage device of the EOU 206 stores a table, ie, a map, of the optimum advance angle amount T determined by engine parameters such as engine speed and engine load (accelerator opening). The EOU 206 reads the optimum advance angle amount T according to the engine parameters input thereto, measures the time difference t between the output signal person signal and the output signal B signal, and compares T and t. Then, the electromagnetic shutoff valves 208 and 210 are feedback-controlled so that the difference between them is always within a certain value.

Regarding the supply of hydraulic oil, as described above, since the hydraulic oil is supplied to the swing vane type actuator 12 after the air bubbles contained in the hydraulic oil are separated in the defoaming tank 300, the swing vane type actuator 12 Each working chamber 6 of the type actuator 12
6a and 66b are supplied with hydraulic oil from which air bubbles have been separated;
When the swing vane 62 drives the input shaft 202 of the injection pump 200 to perform fuel injection, a high torque acts on the swing vane/62. On the other hand, the swinging bay 762 has working chambers 66a, 6
Since it is rotationally driven via the oil pressure of actuator 6b, the oil pressure in the working chambers 66g and 66b increases during fuel injection, but since there are no air bubbles mixed in, the hydraulic oil can be considered almost incompressible, and the actuator The swinging vane 62 also rotates in complete synchronization with the rotation of the housing 46, so that the fuel injection characteristics do not change.

Figure 5 shows the lift of the fuel injector when a defoaming tank 300 is installed to separate air bubbles in the hydraulic oil, and Figure 6 shows the lift of the fuel injector when a defoaming tank 300 is not installed and air bubbles are included in the hydraulic oil. 7 points are shown respectively.

If air bubbles get mixed into the hydraulic oil, each working chamber 6
The air bubbles are compressed because the oil pressure in 6a and 66b increases. Therefore, the swing vane 62 lags behind the actuator housing 46 . As a result, the nozzle lift decreases as shown in FIG. 6, resulting in a significant change in fuel injection characteristics and engine performance.

Further, this rate of change also changes depending on the amount of bubbles in the hydraulic oil, resulting in a problem of lack of stability. However, since the present embodiment is provided with the degassing tank 307 as described above, it operates as shown in FIG. 5, and such a problem does not occur.

FIG. 7 shows a defoaming tank according to a second embodiment of the present invention.

The difference between this embodiment and the first embodiment is that a filter was provided in the defoaming chamber. By providing a filter 409 at the bottom of the defoaming chamber 407, air bubbles are separated and at the same time foreign substances in the hydraulic oil are separated by the filter 409, and the swing vane type actuator 12 is operated without air bubbles or foreign substances. Oil can be supplied. Not only does this rounded injection characteristic remain unchanged, but also the durability of the swing vane type actuator 12 can be greatly improved.

FIG. 8 shows a defoaming tank according to a third embodiment of the present invention.

This embodiment differs from the first embodiment in that a partition plate is provided in the degassing tank to divide it into two chambers. The degassing tank 500 is divided into upper and lower halves by a partition plate 510 into an upper deoiling chamber 507 and a lower deoiling chamber 511, and air bubbles contained in the hydraulic oil flowing into the upper deoiling chamber 507 from the oil inflow pipe 506 are retained. During this time, the hydraulic oil that floats to the top of the degassing chamber 507 and contains many bubbles flows out through the drain pipe 504. Next, the oil from which most of the air bubbles have been removed flows into the defoaming chamber 511 under the pipe 514 provided on the partition plate 510, and the air bubbles contained even slightly are discharged through the drain pipe 512 provided on the bottom plate 502. Completely defoamed hydraulic oil is supplied to the swing vane actuator 12 from the supply pipe 508 .

Effects of the Invention Since the present invention has the above-described configuration and operation, when transmitting rotational motion from the driving shaft to the driven shaft, it is possible to freely change the relative rotational angular position between the two. In addition, this mechanism can be made simple and compact, and its relative rotational angular position can always be controlled stably, thereby making it possible to obtain a rotational motion transmission device that is extremely effective as a variable timing mechanism.

[Brief explanation of the drawing]

FIG. 1 is a partially vertical overall view of the first embodiment of the present invention. FIGS. 1, 2, and 3 are sectional views taken along the line ■-■ in FIG. FIG. 3 shows the output shaft when the angle is advanced; FIG. 4 is a graph showing the rotation detection signals of the actuator housing and the output shaft in the same embodiment; and FIG. FIG. 6 is a graph showing the nozzle lift characteristics of the conventional example, FIG. 7 is a vertical cross-sectional view of the defoaming tank in the second embodiment of the present invention, and FIG. 8 is the graph showing the nozzle lift characteristics of the conventional example. It is a longitudinal cross-sectional view of the defoaming tank in 3rd Example. DESCRIPTION OF SYMBOLS 10... Rotational motion transmission device, 12... Swinging vane type actuator, 22... Drive shaft, 36... Output shaft,
46...actuator housing, 62a162b・
... Swinging vane, 64a, 64b... Fixed vane, f
i6a, 66b - working chamber, 74. a, 74b-coil spring, 200! -・Fuel injection pump, 201・・Input shaft,
208.210...Shutoff valve, 300,400°500
...Defoaming tank, 304,404,504,512...
Drain pipe, 305, 405, 505, 513... orifice.

Claims (1)

[Claims] 1. A variable timing actuator that controls the relative angle between a drive shaft and a driven shaft, the actuator comprising an actuator housing that rotates in synchronization with the drive shaft, and the housing. an output shaft having a swing vane housed in the housing and connected to the driven shaft, the swing vane of the output shaft being rotated relative to the housing by hydraulic pressure introduced into the housing. 1. A rotary motion transmission device, which is supported so as to be able to change its angular position, and further comprises a defoaming device for separating air bubbles in hydraulic oil in the hydraulic pressure introduction circuit. 2. The rotational motion transmission device according to claim 1, wherein the defoaming device comprises a defoaming tank and a drain pipe disposed above the defoaming tank. 3. The rotary motion transmission device according to claim 2, further comprising a filter provided in the defoaming tank to separate foreign matter in the hydraulic oil. 4. A partition is provided in the defoaming tank to divide it into two chambers, and a drain pipe is provided in each chamber to separate air bubbles in the hydraulic oil into two stages. The rotary motion transmission device according to item 2. 5. Claims characterized in that the drive shaft is an engine crankshaft, the driven shaft is an input shaft of a fuel injection pump, and the actuator housing is driven in synchronization with rotation of the crankshaft. The rotational motion transmission device according to item 1.