JPS5825131Y2 - Fluid sequential operation circuit device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid circuit device, ie a hydraulic or pneumatic circuit device, in which two cylinders operate in sequence.

(Only the hydraulic circuit will be explained below.) Conventionally, in a hydraulic circuit equipped with two cylinders, when the cylinders are operated in the first and second order when pressure oil is supplied, an OFF signal is generated, i.e. When discharging pressure oil, the cylinders operate in the second and first order, contrary to when pressure oil is supplied.

For example, as shown in Fig. 1, a first cylinder 1 and a second cylinder 2 are connected in parallel, and the operation start pressure of the first cylinder is Pl, and the operation start pressure of the second cylinder is P2.
The spring force and piston action cross-sectional area are selected so that 2>P1 is set, and by energizing the solenoid 51 of the solenoid valve 5, pressure oil is supplied from the pressure oil source 6 to both cylinders through the ports 53 and 54. When the pressure is supplied to P1, the pipe pressure starts to rise, and first, at low pressure P1, the first cylinder 1 starts operating against the spring 13, and the first piston 12 moves to the right.

The operating speed at this time is determined by the flow path area of the ports 53-54 of the valve 5 and the differential pressure (Ps-Pl).

When this first piston 12 moves rightward and stops at the end, the pressure increases, and when it reaches P2 from P1, the second piston 22 starts moving rightward.

In this state, the pipe pressure is P2Ps, so the first cylinder 1
The piston 12 remains stopped at the right end.

When the second piston 22 reaches the right side and stops, the pipe pressure P
=Ps.

By providing a difference in operating pressure in this manner, the pistons can perform sequential operations.

Next, the operation of each cylinder when lowering the line pressure will be explained with reference to the graph of FIG. 2, in which the horizontal axis is time t and the vertical axis is line pressure P.

(In order to simplify the explanation in the graph, it is assumed that the spring force is always constant and the operation is steady.

) First, when the solenoid valve 5 is turned off at time to and the pipe is connected to the tank via ports 54 and 55, the pipe pressure P becomes
The pressure P2 is determined by the force of the spring 23 and the piston area A2.

The return speed of the piston 22 is determined by the pressure P2 and the fluid resistance of the ports 54 and 55 of the solenoid valve 5.

Then, at time t1 when the piston 22 reaches the left end, the pipe pressure P becomes a pressure P1 determined by the spring force of the spring 13 and the piston area A, and the piston 12 starts its return operation.

In this case as well, the operating speed of the piston 12 is determined by the pressure P1 and the fluid resistance of the ports 54 and 55.

When the piston 12 reaches the left end at time t2, the flow rate passing through the ports t-54, 55 of the valve 5 becomes zero, so the line pressure P becomes atmospheric pressure.

In this way, conventionally, the two cylinders were operated in sequence, and if the first and second cylinders were operated in the order when supplying pressure oil, the second and second cylinders were operated in reverse order when discharging pressure oil. The cylinders operate in the order of 1.

However, depending on the requirements of the equipment, the first, second, first,
A second cylinder operating sequence is often required.

However, no hydraulic or pneumatic circuit device has been seen to date that uses two cylinders and provides a first, second, first, second cylinder operating order depending on whether pressure oil is supplied or discharged.

The present invention was created in response to such demands, and one embodiment of the present invention will be described below with reference to FIG. 3.

In the figure, 1 is the first cylinder similar to the conventional device,
The spring force of the spring 13 and the working cross-sectional area of the piston 12 are selected so that the actuation starts at the working pressure P1.

3 is a second cylinder, and this piston 32 has a poppet 34 and a valve seat 35 as a valve body that opens and closes a left end pressure oil supply part (pressure supply part) 36, and the operation start pressure of this poppet, that is, the pressure oil supply The operating cross-sectional area A35 of the pressure oil supply section 36 and the spring force of the spring 33 are selected so that the opening pressure P3 of the section is higher than Pl.

Immediately after the poppet 34 as a valve body separates from the valve seat 35 and starts operation, the piston 3 is activated at a pressure P3' lower than P1.
The working cross-sectional area A32 of the piston 32 so that the piston 2 moves to the right
is set large, and this cross-sectional area A32 and the spring 33
The piston 32 moves to the right at the low pressure P3' determined by the spring force.

The second cylinder 3 and the first cylinder 1 are connected in parallel as shown in FIG. 2, and this hydraulic circuit is connected to a pressure oil source 6 via a solenoid valve 5.

Also, the throttle 7 connects the second cylinder 3 in parallel with the first cylinder 1.
The ports 53, 5 of the solenoid valve 5 are interposed in the middle of the circuit to the
This is a diaphragm having an aperture with a smaller cross-sectional area than 4.

The operation of the configuration of the present invention will be explained below.

Now, when the solenoid 51 of the solenoid valve 5 is energized, pressure oil flows through the ports 53 and 54, and the line pressure P starts to rise, which is higher than the operation start pressure P3 of the poppet 34, which is higher than the operation start pressure P1 of the first cylinder 1. Since the pressure is low, the piston 12 first moves to the right.

When the piston 12 reaches the right end, the line pressure P further increases from Pl, and when it reaches P3, the poppet 34 serving as a valve body is removed from the valve seat 35.

Immediately after this, hydraulic pressure acts on the end surface of the piston 32, so
The pressure decreases to the actuation starting pressure P3' of the piston 32 and moves the piston 32 to the right.

As mentioned above, the operation start pressure P 3' is set to be lower than Pl, so if the piston 32 continues to operate in this state, the pipe pressure P will become P 3' and the piston 12 will return to the left side. It turns out.

To deal with this problem, a throttle 7 is provided, and the fluid resistance in this part due to the flow during operation of the piston 32 keeps the pipe line pressure P from decreasing below P1, and the piston 32 is held at the right end. Stop at .

In this way, when the solenoid valve 5 is turned ON, the first cylinder and the second cylinder operate in this order, but when the solenoid valve 5 is then turned OFF, the first cylinder and the second cylinder are operated in that order. Explain how it works.

When the electromagnetic valve 5 is turned off in the above-mentioned state, the pipe line is connected to the tank through the ports 54 and 55, and the pipe line pressure P decreases.

In this case, the operation start pressures PI and P3' of both cylinders are PI>
P 3', first the first piston 12 moves to the left.

During this operation, the pipe pressure P2 is constant at P1, so the second piston 32 can move. When the piston 12 returns to the left end, the pipe pressure P decreases, oil is discharged through the throttle 7, and the pipe pressure When P=P3', the piston 32 moves and the poppet 34
The pipe pressure is kept constant at P 3' and moved to the left until it reaches the valve seat 35.

In this way, even when the solenoid valve 5 is turned OFF, the cylinders operate in the first and second order, similar to when the solenoid valve 5 is turned ON.

According to the present invention described above, the first cylinder has an operation start pressure set to Pl, and the opening pressure P3 is greater than Pl.
By applying a signal pressure directly to the first cylinder and through a throttle to the second cylinder to the second cylinder having an operation start pressure P3' lower than Pl, both the ON operation and the OFF operation can be performed. A hydraulic or pneumatic circuit arrangement may be provided that operates in the order of the first cylinder and the second cylinder.

[Brief Description of the Drawings] Fig. 1 is a schematic diagram showing a conventional fluid sequential operation circuit device, Fig. 2 is a graph explaining the operation when the solenoid valve is OFF, and Fig. 3 is a fluid sequential operation circuit device according to the present invention. FIG. In the figure, 1 is a first cylinder, 3 is a second cylinder, 34 is a poppet, 35 is a valve seat, 36 is a pressure oil supply section, 6 is a pressure oil source, and 7 is a throttle.

Claims (1)

[Scope of utility model registration request] In a system in which first and second cylinders having different operation start pressures are connected in parallel to a pressure source to perform sequential operations, the second cylinder is set at a lower pressure than the operation start pressure of the first cylinder. The pressure supply section of the second cylinder is opened and closed by a valve body configured integrally with the piston of the second cylinder, and the opening pressure thereof is set to a higher pressure than the operation start pressure of the first and second cylinders. When the second cylinder is operated, the pipe pressure is applied to the first stage before the pressure supply section of the cylinder.
A fluid sequential operation circuit device characterized in that a throttle is inserted to prevent the pressure from decreasing below the operating start pressure of the cylinder.