JPS5825913B2 - Cylinder piston failure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluid output control device for a double-acting cylinder-piston drive machine, and more particularly to a device for obtaining a fluid flow rate proportional to the force actuating a valve element of a valve arrangement.

U.S. Pat. No. 3,498,411 describes a control device for a cylinder-piston drive as a packet actuator in a packet truck.

In this known control device, in order to accurately displace the packet to a desired working position, a piston is actuated at a speed proportional to the operating force of a valve device that controls the supply of working fluid, and the operating part of the control device is moved to the packet. The system is configured so that the operator can directly operate the packet.

The aforementioned valve arrangements are provided in pairs for supplying pressurized working fluid to one end of the cylinder and discharging working fluid from the other end.

Therefore, in order to control these valve devices, two operating bundles are provided as operating parts in the packet, a throttle valve is connected to each operating bundle, and the two valve devices in the control device main body are controlled by these throttle valves. are operating respectively.

However, operating the two operation bundles individually requires skill and is prone to erroneous operations.

Further, since it is necessary to arrange two throttle valves in the operating portion and connect the operating portion and the main body through separate control fluid conduits, the configuration becomes complicated and large-scale.

SUMMARY OF THE INVENTION An object of the present invention is to provide a control device for a double-acting cylinder-piston drive machine that has excellent operability, is simple in construction, and is compact.

The outline of the control device according to the present invention is as follows.

Each valve element of the two valve devices that control the supply and discharge of pressurized working fluid to and from both ends of the cylinder is actuated by a common motion transmission device consisting of a swing arm.

As the rocker arm pivots in one direction, one valve arrangement supplies pressurized working fluid to one end of the cylinder and the other valve arrangement discharges working fluid from the other end of the cylinder.

When the rocking arm rotates in the other direction, the functions of the two valve devices are exchanged, with the one valve device discharging the working fluid from the one end of the cylinder and the other valve device discharging the working fluid from the other end of the cylinder. supply pressurized working fluid to the

The working fluid pressure needs to be high in order to displace the member or equipment connected to the drive machine with the required force.

Therefore, if the flow rate of the pressurized working fluid cannot be set independently of its pressure, it will not be possible to easily control the piston speed of the drive machine.

In view of this problem, in the present invention, proportional flow valves are used as the two valve devices, which supply the working fluid at a flow rate corresponding to the operating force thereof, and the flow rate of the working fluid is made independent of the supply pressure. This makes the piston speed proportional to the valve operating force.

The work output of the drive machine is adjusted by increasing or decreasing the supply pressure.

A pair of single-acting solenoids are provided to adjust the piston speed by rotating the swinging arm in each direction with a desired force.

The supply current to these solenoids can be controlled by a single control lever located on the packet.

That is, the current supplied to each solenoid, and therefore the piston speed, can be reliably controlled by easy operation of the control lever.

In order to enable the drive machine to operate even during a power outage, it is desirable to provide a manual lever on the swinging arm.

Hereinafter, the present invention will be described with reference to illustrated embodiments.

A piston rod 12 of a cylinder-piston drive machine 10 shown in FIG. 1 is connected to operating members such as upper and lower bucket arms of a packet truck.

A conduit 14 is connected to the rond end of the drive machine 10, and a conduit 16 is connected to the head end.

Due to the arrangement in the figure, the connecting portions of conduits 14 and 16 are referred to as the right and left ends of the cylinder.

A valve arrangement 18 for controlling the supply and discharge of working fluid to and from the drive machine 10 is shown diagrammatically in FIG. 1 and in detail in FIG.

1, the conduit 1 is connected to the housing 20 of the valve device 18.
4, 16, 22, 24 are connected.

The fluid discharged from the drive machine 10 passes through the conduit 22 to the liquid reservoir 2.
5.

Pump 26 draws working fluid from reservoir 25 through conduit 21 and delivers pressurized fluid through conduit 30 to pressure equalization vessel 28 .

A pressurized fluid supply conduit 24 is connected to the pressure equalization vessel 28 .

A pressure actuated switch 32 is coupled to conduit 24 to connect vessel 28.
The pressure inside is transmitted to the switch 32.

Pressure actuated switch 32 connects motor 3 that drives pump 26.
4, and stops the pump 26 when the pressure in the pressure equalizing container 28 exceeds a predetermined value.

The switch 32 has an adjustment member 36 for adjusting the pressure in the container 28 to the desired value.

Pressure activated switches of this type are commonly used in compressed air and hydraulic machinery.

When the valve arrangement is in the first position, the working fluid is in the pressure equalizing vessel 2.
8 to the drive machine 1 via a conduit 24, a valve device 18, and a conduit 16.
Flows into the left end of 0.

This causes the piston and piston rod 12 to move to the right in FIG.

At the same time, from the right end of the drive machine 10, the conduit 14, the valve device 18,
Via conduit 22 the working fluid flows into reservoir 25 .

When the pressure inside the container 28 decreases, the pressure switch 32 drives the motor 34, and the pump 26 sucks working fluid from the reservoir 25 through the conduit 21, and the pressurized working fluid is transferred to the conduit 30.
It flows into the container 28 through the.

When the valve device 18 is in the second position, the working fluid is transferred to the driver 10.
A fluid reservoir 25 flows into the right end of the drive machine 10 from the left end of the drive machine 10.
to be discharged.

The valve device 18 according to the present invention will be explained below.

Ports 14p, 16p, 22p of housing 20 for connecting conduits 14.16, 22.24.

Shown as 24p.

Two main valve chambers 4 are provided in the housing 20 and are substantially parallel to each other.
1.42 shall be provided.

Rods 44°45 slidably engaged with the upper end of each valve chamber
protrudes from the upper end of the housing 20.

O-rings 47 attached to the rods 44 and 45 prevent fluid leakage along the walls of the valve chambers 41 and 42, and the rods 44
．． 45 can be easily slid.

A plug 50 is screwed into the lower end of the valve chamber 41 to close the lower end of the valve chamber 41.

A valve seat 52 that contacts a shoulder 53 formed in the valve chamber 41 is fixed by a plug 50.

A radial opening 54 is provided in the side wall of the plug 50 , and a groove 56 is provided in the inner peripheral surface of the valve chamber 41 to communicate with the inside of the valve chamber 41 .

The groove 56 communicates with the pressurized fluid supply port 24 .

The groove 56 communicates with the pressurized fluid supply port 24 .

A valve element 58 that is slidable within the valve chamber 41 is provided.

The button is brought into contact with the valve seat 52 in the closed position shown in FIG.

The lower end of the valve element 58 slides on the cylindrical inner surface of the plug 50 as a guide.

A spring 59 is engaged between the valve element 58 and the bottom wall of the plug 50 to force the valve element 58 against the valve seat 52.

A movable valve seat element 60 with a cylindrical cross section is provided which can slide using the valve chamber 41 as a guide.

In the illustrated example, the valve seat element 60 is integrally constructed with the rod 44, so that when the rod 44 is pushed down, the valve seat surface 62 touches the valve element 58.
make contact with.

A circumferential groove 6 is connected to the valve chamber 41 in communication with the fluid discharge port 22p.
8 is provided and communicates with a lateral passage 66 provided in the valve seat element 60.

An axial passage 64 is provided within the valve seat element 60 to provide a valve seat surface 62.
and the lateral passage 66 are communicated with each other.

The lower end of the movable valve seat element 60 is provided with a cylindrical inner surface that guides the upper end of the valve element 58, allowing the movable valve seat element 60 and the valve element 58 to slide relative to each other.

A spring 72 is engaged between the fixed valve seat 52 and the underside of the valve seat element 60, forcing the valve seat element 60 upwardly.

An orifice 74 is provided in the valve chamber 41 between the fixed valve seat 52 and the movable valve seat element 60, and communicates with the port 16p communicating with the left end of the drive machine 10.

The bleed valve 16 is screwed into a hole provided in the side wall of the housing 20 using a screw 78, and the effective cross-sectional area of the orifice 74 is determined by adjusting the screw-in dimension of the bleed valve 76.

A swing arm 80 is pivoted to the upright wall of the housing 20 by a pin 82.

The swing arm 80 contacts the upper ends of the rods 44 and 45.

An adjustment screw 84 adjusts the angular position at which the swinging arm 80 contacts the rod 44,45.

Two solenoids 86.8 as actuators of the valve arrangement 18
8 will be provided.

A board 90 of each solenoid is fixed to the upper end of the housing 20, and current is supplied to a coil 94 wound around a ferrous metal magnetic core 92 to energize the required solenoid.

Screw the plunger 96 of the solenoid 86 into the holding member 98.

Opening 1 in which the cylindrical portion of the holding member 98 is provided in the magnetic core 92
Slide inside 00.

The armature ring 102 is attached to the holding member 98 by the screw 104.
When the coil 94 is energized, it is attracted to the magnetic core 92.

The lower end of the cover 106 that protects the moving parts of the solenoid 86 surrounds the base plate 90 and is removably attached to the base plate 90 by a set screw 108 .

The lower end of the plunger 96 is brought into contact with a recess 110 provided on the upper surface of the swing arm 80.

A plunger 96' of the solenoid 88 is brought into contact with a recess 110' at the other end of the swing arm 80.

The solenoid 88 has the same structure as the solenoid 86.

The threaded portion 118 at the lower end of the lever 114 having the bundle 116 at the upper end is screwed into the central portion of the swinging arm 80 .

The distance between the solenoids 86 and 88 is such that the bar 114 is the fulcrum 8.
It is possible to manually move within the required angular range around point 2.

Lever 114 is manually operated when the power supply to solenoids 86,88 is cut off.

One end of the coil 94 of the solenoid 86 is connected to a power supply conductor 120, and the other end is connected to ground through a conductor 122 and a contact 124 of a potentiometer 126.

One end of the coil of solenoid 88 is connected to power supply conductor 130 and the other end is connected to ground via conductor 132 and contact 134 of potentiometer 126.

A manual control lever 136 of the potentiometer 126 pivots about a fulcrum 138 and is maintained in a steady central position by a spring 140.

Contacts 124, 1 are located at the center position of the potentiometer.
The circuits of solenoids 86 and 88 are opened without contact with the falling of 34.

Move the potentiometer control lever 136 to the left in FIG. 2 to apply a small amount of current to the solenoid 86.

When lever 136 is moved further to the left, the effective resistance of contact resistance 124 decreases and the current supplied to solenoid 86 increases.

At this time, the solenoid 86 exerts a large downward force on the plunger 96 to rotate the swinging arm 80, pushing down the rod 44 and operating the valve device.

Move the potentiometer control lever 136 from the center position to the second position.
When the lever 136 is rotated to the right in the figure, a current is supplied to the solenoid 88, and the value of the current increases depending on the angle at which the lever 136 is moved to the right.

A scale 142 is provided on the potentiometer 126, and the lever 1
36 is shown.

Calibration of the scale may be the force acting on the solenoid or the flow of actuating fluid through the valve arrangement.

As discussed below, the fluid flow rate is proportional to the solenoid force.

Current supplied by potentiometer 126 and power supply 120.
Since the force acting on the solenoids 86, 88 varies depending on the voltage at the solenoids 86, 88, an ammeter 144,
, 144' are connected in series.

The force acting on the solenoid changes the scale of the ammeter. Alternatively, it can also be the working fluid flow rate.

Each part in the valve chamber 42 of the valve device 18 is similar to the valve chamber 41, and is indicated by the same reference numeral with III added thereto.

The operation of the valve device will be explained.

When no current is supplied to the lunoid 86, 88, each part is in the position shown in FIG.
The horizontal position is achieved by the action of .

Each valve element 58, 58' is pressed against a fixed valve seat 52, 52' to a closed position, blocking pressurized fluid from port 24p.

No pressurized fluid is supplied to the drive machine 10.

When solenoid 86 is energized, plunger 96 rotates swinging arm 80 and pushes up the other plunger 96'.

Because solenoid 88 is not energized, plunger 96'
There is almost no resistance to push up.

The swinging arm 80 rotates about the fulcrum 82, thereby pushing down the rod 44 and pushing down the valve seat surface 6 of the movable valve seat element 60.
2 contacts the valve element 58 and connects the conduit 16 and the discharge port) 22p
Cut off communication with.

If the rod 44 is further pushed down, the valve element 58 is separated from the fixed valve seat 52, and the pressurized working fluid is transferred from the port 24p to the valve seat 5.
2 and enters the valve chamber 41 above the valve seat 52.

The pressurized fluid is further supplied through orifice 74, bow) 16p, conduit 1
6 and flows into the left end of the drive machine 10.

The pressurized fluid is supplied to the piston and piston rod 12 of the drive machine 10.
Stretch it out and perform the necessary work.

A pressure drop occurs as it passes through orifice 74.

The value of the pressure drop is determined by the cross-sectional area of the orifice 14, ie by adjusting the bleed valve 76.

Furthermore, the value of the pressure drop is determined by the fluid flow rate through the orifice.

Therefore, once the cross-sectional area of the orifice 74 is determined, the value of the pressure drop is proportional to the working fluid flow rate.

A flange 150 is provided when the lower end of the movable valve seat element 60 surrounds the upper end of the valve element 58, and slides within the valve chamber 41 as a piston.

The lower side of the seven-lunge piston 150 is affected by the pressure within the valve chamber 41 upstream of the orifice 14.

The upper side of the seven-lunge piston 150 is subjected to the pressure action in the valve chamber 41 on the downstream side of the orifice 74.

The valve element 58 contacts the valve seat surface 62 and there is no fluid leakage between the valve element 58 and the valve seat surface 62.

Therefore, the pressure difference between the upper and lower surfaces of the seven-lung piston 150 is the value of the fluid pressure drop across the orifice 14 and is proportional to the working fluid flow rate through the orifice.

As the fluid flow rate increases, the pressure drop also increases, and the pressure acting on the underside of the seven-lung piston 150 increases, pushing the movable valve seat element 60 and the rod 44 against the force of the solenoid 86.

When the movable valve seat element 60 moves upward, the valve element 58 is moved by the spring 59.
moves upward together with the valve seat element 60, the distance between the valve element 58 and the fixed valve seat 52 decreases, and the working fluid flow rate decreases.

This automatically adjusts the opening dimension of the valve element 58, i.e. the pressurized fluid flow rate supplied to the left end of the drive machine 10 via the conduit 16, so that the downward force exerted by the solenoid 86 is applied to the spring 59.72. The sum of the force and the pressure difference acting on the flange piston 150 balances the upward force.

The valve arrangement according to the invention is therefore a proportional flow valve, in which the fluid flow rate through the valve arrangement is the force that opens the valve arrangement, i.e. the solenoid 8
It is proportional to the force acting on 6.

The value of the current supplied to the solenoid determines the force produced by the solenoid 86.

When the working fluid is supplied to the left end of the drive machine 10 through the valve chamber 41, the valve element 58' in the valve chamber 42 maintains the position shown in FIG. pushed by.

Since the swinging arm 80 rotates counterclockwise, the right arm of the swinging arm 80 separates from the rod 45.

When the drive piston moves to the right, fluid exits through conduit 14 through port 14p, the gap between valve element 58' and valve seat surface 62', passage 64', lateral passage 66', and port 22p.
, 22 tons of conduit! - and then discharged to the liquid reservoir 25.

To move the piston and piston rod 12 of driver 10 to the left, potentiometer 126 is operated to energize solenoid 88 and shut off solenoid 86.

As a result, the swinging arm 80 rotates clockwise and the rod 4
5 is pressed down, and the rod 44 moves upward.

Valve arrangement 18 operates in the opposite manner as previously described, supplying pressurized fluid to conduit 14 and conduit 16 passing through discharge port 22 to reservoir 2.
It connects to 5.

The piston of the drive machine 10 and the piston rod 12 move to the left.

According to the present invention, the following advantages can be obtained.

(1) The operator can easily and reliably control the double-acting cylinder-piston drive machine by operating only one control lever 136, and there is no risk of erroneous operation.

(2) The operating speed of the driver piston can be precisely controlled by the control lever 136.

That is, the supply current to the solenoid 86, 88 is adjusted by the side split lever 136, and the valve seat element 60° 60' is displaced in accordance with the supply current, thereby supplying the working fluid flow rate to the re-piston 12, and therefore the operating speed of the piston 12. It can be made exactly proportional to the current.

(3) Since the two valve devices that control the supply and discharge of working fluid to and from the drive machine can be selectively operated by a common motion device, the configuration is simple and compact.

[Brief explanation of drawings]

FIG. 1 is a diagram of a cylinder piston drive control device according to the present invention, FIG. 2 is an enlarged sectional view of the valve device in FIG. 1 in a neutral position, and FIG. 3 is an operating position of the valve device in FIG. 2. FIG. 10...-Cylinder piston drive machine, 14゜1
6.22, 24, 27.30... Conduit, 18.
... Valve device, 41.42 ... Valve chamber, 44
, 45... Rod, 50... Plug, 52... Fixed valve seat, 58... Valve element, 54, 72... Spring , 62... Valve seat surface, 64... Movable valve seat element, 14...
Orifice 80... Swinging arm, 86.88...
... Solenoid, 96 ... Plunger, 12
6... Potentiometer, 136...
Lever, 150...flange piston.

Claims (1)

[Claims] 1 A first valve device that controls the supply and discharge of working fluid to one end of the cylinder in a cylinder piston drive machine, a second valve device that controls the supply and discharge of working fluid to the other end of the cylinder, and a first button and a second valve device that controls the supply and discharge of working fluid to and from the other end of the cylinder. a housing in which two valve devices are housed substantially parallel to each other so as to move in the same direction upon similar operation; a common interlocking transmission device that moves the first and second valve devices in mutually opposite directions; and a motion transmission device. a first electromagnetic actuator for moving the motion transmission device in one direction; and a second electromagnetic actuation device for moving the motion transmission device in the other direction; a first valve element for controlling fluid discharge from the driving machine; and a second valve element for controlling fluid discharge from the driving machine, one of the first and second valve elements being configured by a valve element responsive to fluid flow rate; A movable wall is connected to the one valve element so as to be movable therewith, and a movable wall is formed on each side of the movable wall upstream of the throttle passage. Pressure on the upstream side and downstream side of the throttle passage is applied, and the pressure on the upstream side of the throttle passage presses the one valve element toward the closed position with a force that increases as the flow rate passing through the throttle passage increases. , controlling the supply current to each electromagnetically actuated device by: 1 controlling the supply current to each electromagnetically actuated device by making the flow rate of the actuating fluid through the valve device proportional to the supply current to said electromagnetically actuated device necessary to hold said one valve element in an open position; An output control device for a cylinder-piston drive machine, characterized in that the control lever comprises a double control lever, the control lever being adjustable to different positions depending on the required flow rate of fluid passing through the one valve element.