JPH0771372A - Pressure oil dischrge adjustment in viscous fluid pump and its device - Google Patents

Abstract

PURPOSE:To lighten a burden to an operator by way of facilitating discharge adjusting operation of an oil pump by adjusting discharge by wag of previously setting the required discharge and automatically controlling engine speed and an oil pump inclined rotation angle in accordance with this set value. CONSTITUTION:Engine speed of an engine 3 driving a variable capacity oil pump 2 is adjusted by an adjusting lever 15 operated by an electromagnetic proportional actuator 16. Additionally, an inclination of the variable capacity oil pump 2 is adjusted by an adjusting lever 17 operated by an electromagnetic proportional actuator 18. Additionally, to both of the electromagnetic proportional actuators 16, 18, each of amplifiers 19, 20 is respectively connected. So as to previously set required discharge, discharge setting commanding voltage is added to both of the amplifiers 19, 20 by a voltage regulator VR1. In the meantime, when priority driving whether it is engine speed priority or inclined rotation angle priority is selected, after it becomes the maximum value in either case, an excessive portion of the discharge setting commanding voltage is added to an objective amplifier and discharge is adjusted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention adjusts the discharge amount of pressure oil discharged from an oil pump in a so-called piston type viscous fluid pump that sucks and discharges viscous fluid by advancing and retracting a piston. Method and apparatus.

[0002]

2. Description of the Related Art Of the conventional viscous fluid pumps of this type, which employs an oscillating valve type as an intake / discharge switching valve, as an example, as shown in FIG. 4, a variable displacement oil pump connected to a tank 1 is shown. 2 is driven by the power of the engine 3, and in the middle of a pressure oil supply / discharge line 6 connecting the discharge side of the oil pump 2 and the head side pressure chambers of the tank 1 and the two main hydraulic cylinders 4 and 5. Is provided with an electromagnetic four-way valve 7, and the rod-side pressure chambers of both the main hydraulic cylinders 4 and 5 are connected by a sealing circuit 8, and the pressure oil discharged from the oil pump 2 is switched by switching the electromagnetic four-way valve 7. Alternately main hydraulic cylinder 4 or 5
Of the main hydraulic cylinders 4 and 5 supplied to the head side pressure chamber of
Are alternately moved forward and backward, the two liquid pressure feeding cylinders (not shown) are alternately switched to the suction side or the discharge side, and the viscous fluid in the hopper can be sucked and discharged. Is done.

Further, in the middle of a pressure oil supply / discharge line 11 for supplying / discharging pressure oil to / from the rocking cylinders 9 and 10 for switching the rocking valves as the main hydraulic cylinders 4 and 5 alternately move forward and backward. Is provided with an electromagnetic four-way valve 12, and the electromagnetic four-way valve 1
By switching 2, the rocking cylinders 9 and 10 are alternately moved forward and backward to switch the rocking valves.

In the viscous fluid pump having the above-described structure, the most basic pump performance is to stabilize the discharge amount of the pressure oil to a required value.

[0005]

However, in the conventional viscous fluid pump, the variable displacement oil pump 2 is used, and the discharge amount thereof is adjusted by the two-dimensional control of the engine speed and the oil pump tilt angle. Therefore, there is a problem that the operator must set the discharge amount while operating each adjustment lever.

Therefore, according to the present invention, the required discharge amount is set in advance, and the discharge amount is adjusted by automatically controlling the engine speed and the oil pump tilt angle in accordance with the set values. Is what you are trying to do.

[0007]

In order to solve the above problems, the present invention inputs a discharge amount setting command voltage, then selects engine speed priority, and keeps the oil pump tilt angle at a minimum. The engine speed is increased to a value corresponding to the discharge amount setting command voltage to adjust the discharge amount, and when the engine speed does not reach the discharge amount setting command voltage even if the engine speed is the maximum, the excess voltage of the command voltage is automatically used for oil Either increase the pump tilt angle to adjust the discharge amount to the set value, or select tilt angle priority and keep the engine speed at a minimum until the oil pump tilt angle is reached until the discharge amount setting command voltage is reached. The discharge amount is adjusted by increasing the turning angle, and when the tilt angle becomes maximum and the discharge amount setting command voltage is not reached, the surplus voltage of the command voltage automatically increases the engine speed and discharges. How to adjust the amount to the set value and That.

Further, the engine speed and the oil pump tilt angle are adjusted by a preset engine speed setting command voltage and oil pump tilt angle setting command voltage to adjust the discharge amount.

Furthermore, the variable displacement oil pump is connected so that it is driven by the engine, and the adjustment of the engine speed and the oil pump tilt angle are performed by separate electromagnetic proportional actuators. In the pressure oil discharge amount adjusting device in, the voltage for adding the discharge amount setting command voltage to the amplifier connected to the electromagnetic proportional actuator for adjusting the rotation speed and the amplifier connected to the electromagnetic proportional actuator for adjusting the tilt angle. The regulator is connected separately by switching the rotation speed priority and the tilt angle priority switch, and the surplus of the discharge amount setting command voltage added to the one amplifier is transmitted to the other amplifier. , A structure in which the surplus of the discharge amount setting command voltage added to the other amplifier can be connected to each other so as to be transmitted to one amplifier To.

Further, a voltage regulator for adding a rotation speed setting command voltage can be connected to the rotation speed adjusting amplifier, and a voltage adjustment for adding the tilt angle setting command voltage to the tilt angle adjusting side amplifier. A preset operation can be performed by connecting a device, and a priority operation of rotation speed priority and tilt angle priority and a preset operation can be selected by switching a switch.

[0011]

In both the engine speed priority and the oil pump tilt angle priority, the required discharge amount is set in advance by adding the discharge amount setting command voltage. The engine rotation speed is increased until the rotation speed reaches the maximum value, and the tilt angle of the oil pump is increased by the surplus of the command voltage when the speed does not reach the command command voltage for setting the discharge amount. Can be adjusted to When the oil pump tilt angle is prioritized, the tilt angle is increased to adjust the discharge amount, but when the maximum tilt angle does not reach the discharge amount setting command voltage, the surplus of the command voltage causes the engine speed to increase. Is automatically raised, so that the set discharge amount is adjusted.

When the rotation speed setting command voltage and the tilt angle setting command voltage are applied to each amplifier, the rotation speed and the tilt angle are adjusted to the set values by the setting command voltage.

[0013]

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

1 and 2 show an embodiment of the present invention. In a circuit configuration similar to that of the piston type viscous fluid pump shown in FIG. 4, the variable displacement oil pump 2 and the engine 3 are shown in FIG. As shown, the variable displacement oil pump 2 is driven by the power from the engine 3 by being integrally coupled through the coupling member 13, and the engine 3 is provided with an engine governor 14 for controlling the rotation speed. An electromagnetic proportional actuator 16 is provided which operates the adjusting lever 15 of the engine governor 14 to continuously set the rotation speed from the minimum to the maximum.

On the other hand, the variable displacement oil pump 2 is provided with an electromagnetic proportional actuator 18 for adjusting the tilt angle by operating an adjusting lever 17 for adjusting the tilt angle.

Amplifiers 19 and 20 are connected to the electromagnetic proportional actuator 16 on the side of the engine 3 and the electromagnetic proportional actuator 18 on the side of the variable displacement oil pump 2, respectively. The discharge amount setting command voltage for setting is added by the voltage regulator VR1, and between the amplifiers 19 and 20, the amplifier 19 to the amplifier 20 and vice versa. So that a voltage is applied to 19,
When the discharge amount setting command voltage is added to the amplifier 19 by the voltage regulator VR1 in order to set the required discharge amount in advance,
The engine speed is increased by the electromagnetic proportional actuator 16 until it corresponds to the command voltage, and the adjusting lever 1
Even if 5 reaches the limit switch LS1 and the number of revolutions reaches the maximum, if the command voltage is not reached, the surplus voltage is transmitted from the amplifier 19 to the amplifier 20 and the tilt angle is increased by the electromagnetic proportional actuator 18. Further, when the discharge amount setting command voltage is added to the amplifier 20 by the voltage regulator VR1, the tilt angle is increased by the electromagnetic proportional actuator 18 until it corresponds to the above command voltage, and the adjusting lever 17 reaches the limit. If the command voltage is not reached even if the tilt angle is maximized by reaching the switch LS2, the surplus voltage is transmitted from the amplifier 20 to the amplifier 19 so that the engine speed is increased.

Further, the rotation speed setting command voltage and the tilt angle setting command voltage are added to the amplifiers 19 and 20 by the voltage regulators VR2 and VR3 in order to enable the preset operation. Thus, the rotation speed and the tilt angle can be adjusted to the set values.

Switching of the rotation speed priority, tilt angle priority operation, and preset operation for presetting the required discharge amount is based on the electric circuit diagram shown in FIG. As shown in FIG. 2A, an amplifier 19 that operates the electromagnetic proportional actuator 16 to operate the adjustment lever 15 to control the rotation speed, and an electromagnetic proportional actuator 18 that operates the adjustment lever 17 to control the tilt angle. The amplifier 20 to be connected is connected to the power source DC with the a contact X1 closed, and the voltage regulator VR1 for adding the discharge amount setting command voltage is closed with the a contact X3 closed.
, And are connected to the amplifier 20 by closing the a-contact X4, and the amplifiers 19 and 20 are connected to the a-contact X5 or the a-contact X6.
It is designed to be connected when is closed. During preset operation, the a contact X2 is closed to connect the amplifiers 19 and 20 to the power source DC, the voltage regulator VR2 for adding the rotation speed setting command voltage to the amplifier 19, and the tilt angle setting command voltage. Are connected to the amplifier 20.

The opening and closing of each contact in FIG. 2A is performed as shown in FIG.
Switch operation.

In the discharge amount control of the variable displacement oil pump 2 driven by the engine 3, the relationship between the discharge pressure P and the discharge amount Q is represented by a constant horsepower line as shown in FIG. Figure 3
In the above, the engine speed N and the oil pump tilt angle q have the following relationship, but N can be set steplessly from the maximum to the minimum. ACDB has N maximum and q maximum. AFGE is N minimum and q maximum. ACH has N maximum and q minimum. AFI is N minimum and q minimum.

In the case where the required discharge amount is set in advance and the oil pump 2 is operated according to the load, when the control giving priority to the engine speed is performed, the voltage regulator is first set. After inputting the discharge amount setting command voltage to VR1 and turning on the switch SW1 in FIG. 2B, turn on the switch SW2 to the relay X2 side to excite the relay X1 on the priority operation side, and then switch S
Insert W3 to the relay X3 side which gives priority to the rotation speed. As a result, the relay X1 is excited to close the a-contact X1. When the switch SW3 is turned on, the relay X3 is excited to close the a-contact X3 in FIG. 2 (a). 19, the electromagnetic proportional actuator 16 operates to operate the adjusting lever 15 to increase the engine speed until it corresponds to the discharge amount setting command voltage added to the amplifier 19. At this time, the tilt angle of the oil pump 2 remains the minimum. When the adjusting lever 15 reaches the limit switch LS1 and the engine speed reaches the maximum, the limit switch LS1 is actuated, as shown in FIG.
At a, the contact a X5 is closed, and the amplifier 19 and the amplifier 20 are connected.

At this time, when the discharge amount setting command voltage added by the voltage regulator VR1 is equal to or smaller than the voltage required to reach the maximum rotation speed, when the engine 3 is at or before the maximum rotation speed. Is the set discharge amount, but when the discharge amount setting command voltage is higher than the voltage required to reach the maximum rotation speed, the maximum engine rotation speed does not reach the discharge quantity setting command voltage. So
The excess voltage is transmitted from the amplifier 19 to the amplifier 20 and added, whereby the electromagnetic proportional actuator 1 is automatically
8 is actuated, the tilt angle is increased by the adjusting lever 17, and the tilt angle is automatically controlled until the discharge amount reaches the discharge amount setting command voltage.

On the other hand, when the required discharge amount is set in advance and the control giving priority to the oil pump tilt angle is performed, the switches SW1 and SW2 in FIG. 2B are turned on as described above. In this state, the switch SW3 is put on the relay X4 side to excite the tilt angle priority relay X4. As a result, the a-contact X4 in FIG. 2A is closed and the voltage regulator V
The discharge amount setting command voltage is added to the amplifier 20 by R1, and the electromagnetic proportional actuator 18 operates to increase the tilt angle of the oil pump 2 by the adjusting lever 17 until it corresponds to the discharge amount setting command voltage. At this time, the engine speed remains at the minimum. Adjustment lever 17 is limit switch L
When it reaches S2 and the tilt angle becomes maximum, the contact a6 is closed and the amplifiers 20 and 19 are connected by the operation of the limit switch LS2 in FIG. At this time, when the discharge amount setting command voltage added by the voltage regulator VR1 is equal to or smaller than the voltage required to reach the maximum tilt angle, the tilt angle becomes the maximum or the tilt before this. The discharge amount at the turning angle becomes the set discharge amount,
When the discharge amount setting command voltage is higher than the voltage required to reach the maximum tilt angle, the maximum tilt angle does not reach the discharge amount setting command voltage. Therefore, the amplifier 20 to the amplifier 19 When the surplus voltage is transmitted via the a-contact X6 and added, the electromagnetic proportional actuator 16 automatically operates and the adjusting lever 15 increases the engine speed, and the discharge amount corresponding to the discharge amount setting command voltage. The engine speed is controlled so that

As described above, when the required discharge amount is set by the discharge amount setting command voltage with priority on the rotation speed or the tilt angle, the engine speed and the oil pump tilt angle are automatically controlled appropriately for the load. As a result, the pump can be operated under the most efficient conditions according to the load.

When the required discharge amount is set in advance, whether the engine speed or the oil pump tilt angle is prioritized is determined according to the property of the viscous fluid to be handled. For example, when pumping a low-viscosity fluid such as low slump concrete that has a large pumping load, in order to realize stable pumping, the engine speed adjustment that can increase or decrease the load horsepower is used as the primary operation to increase the discharge pressure. In addition to this, after the maximum rotation speed is reached, the tilt angle is adjusted as a secondary operation. On the other hand, in the case of a viscous fluid with a comparatively small load such as building concrete, the primary operation is adjusted to adjust the tilt angle to achieve low noise and high efficiency operation, and after reaching the maximum tilt angle, The engine speed is adjusted as the next operation. Therefore, if the pressure oil discharge rate is adjusted by giving priority to the engine speed, it will be easier to apply to fluids with low viscosity such as low slump concrete, and if the pressure oil discharge rate is adjusted by giving priority to the tilt angle, it will become A large amount of highly viscous fluid can be pumped.

Next, the switch SW2 in FIG.
Is switched to the relay X2 side, the operation is switched from the priority operation to the preset operation, and the relay X2 is excited, so that
The a-contact X2 at is closed. While inputting the rotation speed setting command voltage to the voltage regulator VR2,
When the tilt angle setting command voltage is input to 3, the voltage adjuster VR2 applies a rotation speed setting command voltage to the amplifier 19, the electromagnetic proportional actuator 16 operates, and the adjusting lever 15 adjusts the engine speed. The rotation speed is automatically adjusted to a set value according to the rotation speed setting command voltage, while the tilt angle setting command voltage is added to the amplifier 20 by the voltage regulator VR3, whereby the electromagnetic proportional actuator 18 operates. The tilt angle is adjusted to the set value. As a result, the adjustment position of the voltage regulator VR2 is set as the rotational speed that provides the lowest fuel consumption and low fuel consumption, and the adjustment position of the voltage regulator VR3 is set to the tilt angle at which the pump efficiency is highest. By setting as, it becomes possible to economically operate with minimum energy loss.

Although the suction / discharge valve of the viscous fluid pump is shown as the oscillating valve type, it is needless to say that it may be of the slide valve type, and other various changes are made without departing from the scope of the present invention. Of course, it is possible to add.

[0028]

As described above, according to the method and apparatus for adjusting the pressure oil discharge amount in the viscous fluid pump of the present invention, when the required discharge amount is set in advance, when the engine speed is prioritized for operation. The number of revolutions is increased by the discharge amount setting command voltage, and when the maximum number of revolutions does not reach the above-mentioned discharge amount setting command voltage, the tilt angle is automatically increased so that the discharge amount becomes the set value. When operating with priority given to the oil pump tilt angle when setting the required discharge amount, the tilt angle is increased by the discharge amount setting command voltage, and the maximum tilt angle does not reach the above discharge amount setting command voltage. In this case, the engine speed is automatically increased so that the discharge amount becomes the set value, and the speed priority and the tilt angle priority can be selected.
In addition, preset operation can be selected so that the engine speed and oil pump tilt angle are set, and the rotation speed and tilt angle are set by adding the rotation speed setting command voltage and tilt angle setting command voltage. Since it can be adjusted to, the following excellent effects can be obtained. (i) By adjusting the discharge amount by giving priority to the number of revolutions, a fluid having a large pumping load such as low slump concrete can be stably pumped, and it becomes easy to apply to a fluid having such a large pumping load. (ii) By adjusting the discharge amount by giving priority to the tilt angle, it is possible to perform large-volume pumping in the case of a fluid with a relatively small pumping load such as building concrete, and realize low noise and high efficiency operation. (iii) The preset operation allows the rotational speed to be set in advance to a low fuel consumption rotational speed, and the tilt angle to be set in advance to a position where high efficiency is achieved, enabling economical operation that minimizes energy loss. (iv) Since the adjustments (i) to (iii) are selected by operating the switch, the discharge amount adjusting operation becomes easy and the operator's burden is reduced.

[Brief description of drawings]

FIG. 1 is a schematic diagram of engine speed adjustment and oil pump tilt angle adjustment showing an embodiment of the present invention.

FIG. 2 shows an electrical circuit embodying the invention,
(A) is a circuit diagram showing the electrical connection state of FIG. 1, and (B) is a sequence diagram.

FIG. 3 is a relationship diagram of a discharge pressure and a discharge amount showing a control state of an oil pump.

FIG. 4 is a hydraulic circuit diagram showing an example of a piston-type viscous fluid pump.

[Explanation of symbols]

 2 Variable capacity oil pump 3 Engine 14 Engine governor 15 Adjustment lever 16 Electromagnetic proportional actuator 17 Adjustment lever 18 Electromagnetic proportional actuator 19, 20 Amplifier VR1, VR2, VR3 Voltage regulator LS1, LS2 Limit switch

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location G05D 16/20 D 8610-3H A 8610-3H

Claims (5)

[Claims] 1. A discharge amount setting command voltage is input, and then engine speed priority is selected to increase the engine speed until the oil pump tilt angle is at a minimum until the engine speed corresponds to the discharge amount setting command voltage. The viscous fluid is characterized in that the discharge amount is adjusted by adjusting the discharge amount, and when the maximum rotation speed does not reach the command voltage, the tilt angle is automatically increased by the surplus voltage of the command voltage to adjust the discharge amount to a set value. Method of adjusting pressure oil discharge rate in pump. 2. A discharge amount setting command voltage is input, then tilt angle priority is selected, and tilt angle adjustment is increased to a value equivalent to the discharge amount setting command voltage while the engine speed is minimized. The viscosity is characterized in that the discharge amount is adjusted by adjusting the discharge amount, and when the maximum tilt angle does not reach the command voltage, the surplus voltage of the command voltage automatically increases the engine speed to adjust the discharge amount to a set value. A method for adjusting the pressure oil discharge rate in a fluid pump. 3. The oil pump adjusts the engine speed to a set value by a preset rotation speed setting command voltage, and adjusts the tilt angle to a set value by a preset tilt angle setting command voltage. A method for adjusting the pressure oil discharge amount in a viscous fluid pump, comprising: adjusting the discharge amount of 4. A viscous fluid pump in which a variable displacement oil pump is connected to be driven by an engine, and the engine speed and the oil pump tilt angle are adjusted by separate electromagnetic proportional actuators. In the pressure oil discharge amount adjusting device in, an amplifier connected to the electromagnetic proportional actuator for adjusting the rotation speed, and an amplifier connected to the electromagnetic proportional actuator for adjusting the tilt angle,
The voltage regulator that adds the discharge amount setting command voltage is connected separately by switching the rotation speed priority and tilt angle priority switches, and the surplus of the discharge amount setting command voltage added to one of the above amplifiers. Is transmitted to the other amplifier,
Also, the pressure oil discharge amount adjusting device in a viscous fluid pump is characterized in that the surplus amount of the discharge amount setting command voltage added to the other amplifier can be connected to each other so as to be transmitted to one amplifier. 5. A voltage adjuster for adding a rotation speed setting command voltage to an amplifier on the rotation speed adjustment side, and a voltage adjustment for adding a tilt angle setting command voltage to the tilt angle adjustment side amplifier. 5. The pressure in a viscous fluid pump according to claim 4, wherein the operation can be connected so that a preset operation can be performed, and a priority operation of rotation speed priority, tilt angle priority and preset operation can be selected by switching a switch. Oil discharge amount adjusting device.