JPH05863Y2 - - Google Patents

Description

[Detailed description of the invention] [Summary of the invention] The present invention is capable of obtaining positive and negative pressure signals at a certain rotation speed of a rotary pump, and uses the discharged pressurized oil as the drive source of the actuator. The present invention relates to a rotation signal extraction device that can be used as a rotation signal.

[Conventional technology]

Detecting the rotation speed of an internal combustion engine is necessary for normal operation of the internal combustion engine, and various rotation speed sensors have been proposed.

Typical rotation speed sensors include centrifugal weight sensors and electrical sensors. The centrifugal weight type sensor uses the centrifugal force of the centrifugal weight itself as an actuator, and because it uses unstable centrifugal force, it is difficult to obtain a large control force. Also, in order to obtain a large control force, it is necessary to increase the weight of the weight itself.
It has been difficult to obtain a miniaturized device.
In the case of electric sensors, stepping motors or solenoid valves are used as actuators, but these have the drawbacks of complex mechanisms and circuits, poor reliability, and disadvantages in terms of cost.

For example, Japanese Utility Model Application Publication No. 57-662 has been proposed as a rotational speed detection device for an internal combustion engine. This device is
Instead of detecting fuel injection pressure or explosion pressure vibration in the combustion chamber, a pressure detector is installed in the lubricating oil passage to detect the pulsation of the lubricating oil pressure that occurs inside the lubricating oil passage of the internal combustion engine. The detected signal is electrically processed by an electrical signal processing device that converts it into an electrical signal proportional to the engine rotational speed, and the obtained electrical signal is displayed as the engine rotational speed.

This device is superior to the method described above in that it detects the rotational speed of the internal combustion engine from the pulsation of the lubricating oil, but the device is complicated and the signal is used to drive the actuator. This requires a separate electrically operated device, which makes the device expensive.

On the other hand, a vehicle speed sensor pump is attached to the power steering system of an automobile to detect the speed of the vehicle, detect the level of response sensitivity to steering operations, and supply pressure oil to the power steering system in accordance with the vehicle speed. A device for controlling the supply of is proposed in Japanese Utility Model Application Publication No. 56-94961.

However, the device only functions as a vehicle speed sensor, and a separate pump must be used as a power source for driving the actuator, which inevitably complicates the device.

[Purpose of invention]

The present invention eliminates the drawbacks of the conventional rotation speed sensor and provides a rotation signal extraction device that can simultaneously perform the functions of a rotation speed sensor and a pump serving as a drive source for an actuator. It is.

[Summary of the idea]

To achieve the above object, the present invention provides a rotary pump with a cylindrical rotating body having a centrifugal opening/closing valve, connects an inlet and a discharge port of the pump to a hydraulic outlet via the valve, and The rotation signal extracting device is such that the suction port or the discharge port is selectively connected to the hydraulic pressure outlet by the valve as the rotating body rotates.

〔Example〕

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

FIG. 1 is a cross-sectional view of a rotation signal extraction device according to an embodiment of the present invention, FIG. 2 is a cross-sectional view of FIG. 1,
FIG. 3 is a cross-sectional view of FIG. 1, and the rotational signal extracting device 1 is composed of a rotary pump section 2 and a signal extracting section 3 installed adjacent to the rotary pump section 2.

In this embodiment, a trochoid type oil pump is used as the rotary pump section 2. This rotary pump includes a pump housing 4 and a groove 5 provided around the opening surface of the pump housing 4.
An inner rotor 7 and an outer rotor 8 are installed in a housing that is closed with a cover 6 and has an O-ring installed inside.
is provided eccentrically, and by driving the inner rotor 7 fixed to the drive shaft 9, the outer rotor 8 is driven to pressurize the oil O sucked in from the suction port 10 and discharged from the discharge port 11. It is configured as follows.

A rotation signal detection device 1 is provided adjacent to the pump wall 4a of the rotary pump section 2. In this rotation signal detection device 1, a cylindrical rotating body 21 is rotatably housed in a cap-shaped housing 20 by a drive shaft 9, and the housing 20 is provided with a hydraulic pressure outlet 26, which is not shown in the figure. Not connected to actuator.

A centrifugal opening/closing valve 24 consisting of a cylinder 22 and a plunger 23 is provided in the diametrical direction of this cylindrical rotating body 21, and a groove 25 connected to the hydraulic pressure outlet 26 is provided along the outer periphery.

A discharge side annular groove 28 formed on the outside and a suction side annular groove 29 formed on the inside are concentrically provided on the side where the cylindrical rotating body 21 contacts the pump wall 4a. The discharge side annular groove 28 is formed on the pump wall 4a.
It is connected to the discharge side of the rotary pump section 2 through a discharge side oil hole 30 provided in the rotary pump section 2 . Further, the suction side annular groove 29 is connected to the suction side of the rotary pump section 2 through a suction side oil hole 31 provided in the pump wall 4a.

The cylinder 22 constituting the centrifugal opening/closing valve 24, the discharge side annular groove 28, and the suction side annular groove 29 are connected through oil holes 30a, 30a, respectively. Note that 2a is a discharge port formed in the cover 6, and 2b is a discharge port formed in the cover 6.
is a suction port formed in the pump housing 4.

Plunger 23 constituting centrifugal opening/closing valve 24
As shown in FIG. 4, a first large diameter portion 23A, a small diameter portion 23a, and a second large diameter portion 23B are formed, and a through hole 23b is formed in the vertical direction, and an outer surface of the small diameter portion 23a is formed. A conductive hole 23c is formed by connecting the through hole 23b and the through hole 23b. As shown in FIG. 5, when the plunger 23 is fitted into the cylinder 22, it is pressed by a spring 33 whose one end is supported by a stopper 34 provided on the outer diameter side of the cylindrical rotating body 21. ing. If the stopper 34 is screwed to the cylinder 22 and its position can be adjusted, the set force of the spring 33 can be finely adjusted.

Next, the operation of the rotation signal extracting device according to the present invention will be explained with reference to FIGS. 5 to 7.

The drive shaft 9 rotates as the internal combustion engine rotates,
Inner rotor 7 fixed to this drive shaft 9
The outer rotor 8 rotates and functions as a pump, and the cylindrical rotating body 21 rotates and the centrifugal opening/closing valve 24 built into it rotates the inlet side and outlet side of the rotary pump section 2. This means switching between the two sides.

[Closed state]

A cylindrical rotating body 21 rotated by the drive shaft 9
Centrifugal force acts on the plunger 23 due to the rotation of
Spring 3 that presses this plunger 23
3, but if the set force of this sprig 33 is greater than the centrifugal force, the state shown in FIG. 5 will occur, and the plunger 23 will come into contact with one end of the cylinder 22 (the top surface on the drive shaft 9 side) and stop. . In this state, the first large diameter portion 23A of the plunger 23 closes the discharge side hole 30a, but the second large diameter portion 23B has moved to a position away from the suction side hole 31a. This suction side hole 31a is not closed.

Therefore, the negative pressure V generated by the suction of the rotary pump section 2 via the suction side oil hole 31a connected to the suction port 10 of the rotary pump section 2 and the suction port 2b is transferred to the small diameter portion of the plunger 23. Conduction hole 2 of 23a
3c, it acts on the through hole 23b, and acts on the hydraulic pressure outlet 26 via the groove 25 provided in a strip shape at the center of the outer circumference of the cylindrical rotating body 21.

When an actuator (not shown) is connected to this hydraulic pressure outlet 26, the action of this negative pressure V causes the actuator to move backward, for example.

[Signal switching status]

Next, as the rotation speed of the internal combustion engine increases, the rotation of the cylindrical rotating body 21 of the rotation signal extraction device 1 also increases,
When the centrifugal force acting on the plunger 23 fitted into the cylinder 22 provided on the cylindrical rotating body 21 increases and this centrifugal force exceeds the set force of the spring 33, the plunger 23 moves inside the cylinder 22 as shown in FIG. Move in the outer diameter direction (upward in the figure).

This state usually occurs instantaneously, but since the two large diameter portions 23A and 23B of the plunger 23 simultaneously close the suction side oil hole 31a and the discharge side oil hole 30a, the pressure inside the cylinder 22 instantly increases. is maintained at 0 or the previous state.

[Positive pressure operating state]

As the rotational speed of the internal combustion engine further increases from the signal switching state shown in FIG. As a result, the state shown in FIG. 7 is reached.

In this state, the plunger 23 is stopped from moving by the protrusion of the stopper 34, and the first large diameter portion 23A opens the oil hole 30a on the discharge side, but the second large diameter portion 23B opens the oil hole 30a on the suction side. The oil hole 31a is closed. In this state, the oil O under the positive pressure P pressurized by the pump part 1 flows through the small diameter part 23a of the plunger 23, the through hole 23b, and the hole 34a formed in the center of the protrusion of the stopper 34 from the discharge side oil hole 30a. Oil O at positive pressure P is discharged to the oil pressure outlet 26 via the oil pressure outlet 26.

As mentioned above, the rotary pump section 2 is operated under the positive pressure P.
The oil O sent out from the rotation detecting section 1 is taken out via the oil pressure outlet 26 to an external circuit such as an actuator.

FIG. 8 shows the signal pattern accompanying the oil pressure fluctuation explained with reference to FIGS. 5 to 7, and assumes the negative pressure operating state shown in FIG. A switching state is shown, and a positive pressure operating state shown in FIG. 7 is shown.

[Effect of idea]

In the present invention, a rotary pump is provided with a cylindrical rotating body having a centrifugal opening/closing valve, and an inlet and a discharge port of the pump are connected to a hydraulic pressure outlet through the valve. The present invention is a rotation signal extracting device in which the suction port or the discharge port is selectively connected to the hydraulic pressure outlet by the valve, and the following effects can be achieved.

The negative pressure and positive pressure generated in the rotary pump section are moved by the centrifugal force of the plunger that constitutes the centrifugal opening/closing valve mechanism as the rotation signal extraction device rotates, and the negative pressure and positive pressure generated in the rotary pump section are moved through the discharge port side passage (positive pressure side oil Since switching is selectively performed between the suction port side passage (hole) and the suction side passage (negative pressure side oil hole), a pressure signal consisting of negative pressure and positive pressure as shown in FIG. 8 can be obtained.

This pressure signal that changes from negative pressure to positive pressure is generated at a predetermined pressure level depending on the weight of the plunger that makes up the valve mechanism, the strength of the spring that presses the plunger and provides set force, and the rotational speed of the cylindrical rotating body. It is possible to obtain positive and negative oil pressure signals.

Moreover, since the oil pressure signal is generated as the rotary pump rotates in conjunction with the rotation of the internal combustion engine, it is possible, for example, to control various devices by using the change in positive and negative pressure. Various actuators can be controlled using the oil sent out from the pump.

That is, according to the rotation signal extraction device according to the present invention, it is possible to extract the rotation signal of the cylindrical rotor that constitutes the rotation signal detection device interlocked with the rotary pump driven by the internal combustion engine as a hydraulic pressure. Since the pressure oil sent out from the rotary pump can be extracted via the signal extraction section, it can also be used as a drive source for a hydraulic actuator.

In the embodiment, a trochoid type pump is shown as an example of the rotary pump, but the present invention is not limited to this, and for example, a vane pump, a gear pump, or other rotary pump can be used.

The rotation signal extraction device according to the present invention can be effectively used as an autotimer for controlling a fuel injection pump of an internal combustion engine.

For example, the piston rod inserted into the cylinder is provided with a spring that pulls the piston back, and the discharge amount of the fuel injection pump is controlled by an actuator that controls the position of the piston by the pressure acting on the cylinder. be able to.

In the above device, for example, (a) when the rotation speed of the internal combustion engine is below a certain first value and the negative pressure generated by the rotation signal extraction device is lower than a certain value, the piston is pulled back by the elastic force of the spring; .

(b) When the rotation speed of the internal combustion engine is larger than the first value and smaller than the second value, the negative pressure becomes large and the piston overcomes the elastic force of the spring and is drawn into the cylinder. do.

(c) Furthermore, when the rotational speed of the internal combustion engine increases to a value larger than the second value, positive oil pressure is obtained from the rotational signal extraction device, and the piston is activated as described in (a) above. is pushed out in the elastic direction of the spring.

In this way, by configuring the actuator to perform the three operations (a) to (c), the autotimer can be operated at the position of the piston.

As described above, the rotation signal extraction device according to the present invention can be used in various applications such as controlling oil pressure according to the rotation speed.

[Brief explanation of the drawing]

The figure shows an embodiment of the present invention.
The figure is a cross-sectional view of the rotation signal extraction device, and the second figure is the first
FIG. 3 is a sectional view taken along the - arrow in FIG. 1. Figure 4 is a perspective view of the plunger that constitutes the centrifugal opening/closing valve;
6 and 7 are cross-sectional views showing the operating state of the centrifugal opening/closing valve, and FIG. 8 is a diagram showing the hydraulic signal obtained by the device according to the present invention. DESCRIPTION OF SYMBOLS 1... Rotation signal detection device, 2... Rotary pump part, 3... Signal extraction part, 4... Pump housing, 7... Inner rotor, 8... Outer rotor, 9... Drive shaft, 10... Suction port, 11... Discharge port, 20... Housing, 21... Cylindrical rotating body, 22... Cylinder, 23... Plunger, 2
4...Centrifugal opening/closing valve, 25...Groove, 26...
Hydraulic pressure outlet, 28...discharge side annular groove, 29...suction side annular groove, 30...discharge side oil hole, 31...suction side oil hole, 33...spring, 34...stopper.

Claims (1)

[Scope of utility model registration request] A rotary pump is provided with a cylindrical rotating body having a centrifugal opening/closing valve, and an inlet and a discharge port of the pump are connected to a hydraulic pressure outlet through the valve. A rotation signal extraction device in which the suction port or the discharge port is selectively connected to a hydraulic pressure extraction port.