WO2018163089A1 - Flow control valve for a single-action cylinder - Google Patents

Abstract

The flow control valve for a single-action cylinder comprises: a control shaft that can be moved between at least three positions, a central chamber for receiving the shaft, an oil inlet for receiving oil from a pump, a tank connection to return the oil, and a link to actuate the cylinder, in which the positions are as follows: neutral position, in which the inlet and the link to the tank are connected, and the link to the cylinder is closed; rising position, in which the inlet and the link to the cylinder are connected; and descending position, in which the link to the cylinder and the link to the tank are connected. The control shaft can be coupled to the cylinder or to a movement system actuated by the cylinder, so that the end-of-travel of the cylinder moves the shaft to the neutral position. The valve can include two pneumatic chambers for moving the shaft between the rising position and the descending position.

Description

 DESCRIPTION

 FLOW DIRECTION VALVE FOR SIMPLE EFFECT CYLINDER

 Technical Domain

The present disclosure relates to an open center flow direction valve which can be operated pneumatically or mechanically.

Background

[0002] Today's valves do not have an efficient mechanical end stop system as a flow control valve for single acting cylinder operation. An important difference from the single acting cylinder operation flow direction valve described herein for existing valves is that in the present disclosure the limit switch may be mechanical or pneumatic, or simultaneously mechanical and pneumatic.

These facts are described to illustrate the technical problem solved by the embodiments of this document.

General description

[0004] The present disclosure relates to a pneumatically or mechanically operated 3/3 configuration (three port / three state) open center flow control valve. Said valve is intended for operation of single acting cylinders and is arranged to be fixed directly thereto through a commercially available standard flange.

One aspect of the present disclosure relates to a flow control valve between a pump and a cylinder comprising at least:

a main body; a first, a second, and a third link connected by shaft and cams;

a sensitive pressure limiter attached to the cylinder to protect against bumps, oscillations, disruption of movement;

wherein the first port receives pump oil, a second port connected to a reservoir, and a third port responsible for connection to the cylinder; a positioning spring and

a flange integrated in the valve body comprising at least two fixing holes which allows the valve body to be connected axially with respect to the cylinder.

Mechanical drive may be possible because the adapter flange (17) allows the distributor to be mounted axially relative to the cylinder (18) due to the positioning spring and two pump mounting holes. This feature makes it possible to mount the limit cable on the shaft and perform the limit switch when the cylinder (18) moves angularly during tilting.

In one embodiment, for better results the valve of the present disclosure may further comprise a sensitive pressure limiter attached to the third port, used to protect against bumps, oscillations, movement disruption and other phenomena to which the cylinders are subjected.

In one embodiment, for best results the valve of the present disclosure may comprise 4 cylinder fixing holes.

Another aspect of the present disclosure relates to a single acting cylinder interconnected to the flow direction valve described in the present disclosure, preferably a cylinder comprising a flange, in particular the SAE 61 flange.

Another aspect of the present disclosure relates to a pump connected to the flow direction valve described in the present disclosure.

[0011] A flow control valve for single acting cylinder operation is described, comprising:

a steering shaft movable between at least three positions; a central chamber for receiving the steering shaft;

an oil inlet to receive oil from a hydraulic pump;

a tank connection to return single acting cylinder oil to a tank; a cylinder connection for driving said cylinder,

wherein the three positions of the steering shaft are: a neutral position, wherein the oil inlet and tank connection are connected together, and the cylinder connection is closed; a rising position, wherein the oil inlet and cylinder connection are connected together; a down position, wherein the cylinder connection and the tank connection are connected to each other.

In one embodiment, the steer shaft is coupled to the cylinder or a cylinder driven drive system such that the cylinder stroke ends the steer shaft to engage the neutral position.

One embodiment comprises two pneumatic chambers for driving the steer shaft between two positions, the up position and the down position, in particular the drive shaft being coupled to a piston reciprocating in these two chambers, and more particularly the drive shaft is coaxially coupled to the piston.

In one embodiment, in the down position, the oil inlet and tank connection are connected to each other to protect if the pump is not turned off when descending.

One embodiment comprises a sensitive pressure limiter attached to the cylinder port for emptying flow to the tank port in case of overpressure.

In one embodiment, the sensitive pressure limiter is connected to the cylinder connection when the cylinder connection is closed by the steering shaft and when it is connected to the oil inlet by the steering shaft. In one embodiment, the sensitive pressure limiter is configured to deflate flow to the tank connection to protect it from bumps, swings, disruption of movement, or combinations thereof.

One embodiment comprises a sensitive pressure limiter attached to the cylinder port for emptying flow to the tank port in case of overpressure.

One embodiment comprises a main pressure limiter connected to the oil inlet to empty the flow rate for connection to the tank in case of excess pressure.

In one embodiment, the oil inlet comprises a backstop that prevents oil from returning to the pump.

One embodiment comprises a positioning spring for returning the drive shaft to neutral position.

One embodiment comprises a flange for direct attachment to the cylinder, in particular a standard flange, in particular SAE 61 or SAE 62 flange.

Further described is a single acting cylinder interconnected to the flow direction valve according to any of the described embodiments.

Further described is a single acting cylinder comprising an adapter flange for mounting the steering valve axially or transversely with respect to the cylinder, in particular such that a cylinder end-stop cable acts the steering shaft towards the cylinder. neutral position as the cylinder moves angularly during tilting.

Further described is an assembly comprising a flow control valve according to any of the described embodiments, a single acting cylinder interconnected to said flow control valve and a hydraulic pump interconnected to said flow control valve. Brief Description of the Figures

For easier understanding, attached are the figures, which represent preferred embodiments not intended to limit the object of the present disclosure.

Fig. 1 - Illustrates an embodiment of the axial section of the valve in neutral state.

Fig. 2 - Illustrates an embodiment of the axial section of the rising valve.

Fig. 3 - Represents the realization of an axial section of the valve in descent state.

Fig. 4 - An embodiment of the valve axial section with a view to the tank connection in neutral state.

Fig. 5 - Front view of one embodiment of the distributor mounted on the cylinder and positioned axially through the adapter flange.

Fig. 6 - Side view of one embodiment of the cylinder mounted manifold and axially positioned through the adapter flange.

[0033] Fig. 7 - Front view of one embodiment of the cylinder mounted distributor, transversely positioned and without adapter flange.

Fig. 8 - Side view of one embodiment of the cylinder mounted manifold, transversely positioned and without adapter flange.

[0035] Fig. 9 - Exploded view of one embodiment of the axially positioned cylinder-mounted manifold (18) through an adapter flange.

Where numeric references represent:

 (1) represents an oil inlet;

 (2) represents the backstop;

 (3) represents the chamber;

 (4) represents a tangue or reservoir;

(5) represents a cylinder; (6) represents valve body;

 (7) represents a camera;

 (8) represents a pressurized air chamber to support shaft movement, and causes oil to flow into the tank / reservoir;

 (9) represents the major limiter;

 (10) represents the end of stroke;

 (11) represents a positioning spring;

 (12) represents cylinder fixing holes;

 (13) represents the pressure limiter;

 (14) represents a shaft;

 (15) represents an instrumentation and control system, for example pressure and temperature;

 (16) represents lever that activates mechanical command or limit switch;

(17) represents an adaptation flange allowing the distributor to be mounted in the axial direction relative to the cylinder;

 (18) represents the cylinder.

The present disclosure relates to a 3/3 configuration (three port / three state) open center flow direction valve; this is a 3 inlet valve: pressure, reservoir / tank, and cylinder (18). Said valve is intended for single acting cylinder operation (18) and is arranged to be attached directly thereto via a commercially available standard flange, such as a SAE Code 61 or SAE Code flange. 62.

In one embodiment, the valve described in the present disclosure may be pneumatically and mechanically operated.

In one embodiment, the valve described in the present disclosure may further comprise additional protections such as pressure limiting in all states and limit switches.

In one embodiment, the valve described in the present disclosure may comprise an oil inlet (1) which receives oil from the pump, backstop (2) which prevents oil from returning to the pump, a tank connection (4) to return single acting system oil, single acting cylinder connection (18), valve body (6), riser ( 7), lowering chamber (8), main limiter (9), limit switch (10), positioning spring (11), single acting cylinder fixing holes (18) according to flange SAE 61 (12 ), sensitive pressure limiter (13), driven shaft (14), pressure take-off (15) and mechanical control (16).

In one embodiment, the valve described in the present disclosure in neutral state (FIG. 1) does not require actuation of any kind, because the positioning spring (11) ensures position. In this state the valve receives oil from the pump through the oil inlet (1) and passes into the tank (4) through the backstop (2) following the chamber (3) until the connection to the tank (4). In this state the connection to the cylinder (18) (5) is closed, which allows the stop of the cylinder (18) at any stage of its course. The connection to the cylinder (18) (5) when closed is protected by the sensitive pressure limiter (13), used to protect against bumps, oscillations, movement interruption and other phenomena to which the cylinders (18) are subjected.

In one embodiment, to cause the single acting cylinder 18 to rise, the valve may be switched to the rising state, for this purpose the shaft must be moved to the right as shown in Fig. 2. The shaft (14) can be moved to the right by air supply in the chamber (7) or mechanical drive. With this movement it is intended that the oil will move from the oil inlet (1) to the connection to the cylinder (18) through the chamber (3).

In this state we have three active safety systems, the sensitive pressure limiter (13) that absorbs the peaks to which the system is subjected, the main limiter

(9) Able to empty all pump flow and limit switch

(10) that being pulled to the left of fig. 2 cancels the rising state, transitioning to the neutral state and nullifying the movement of the single acting cylinder (18).

In one embodiment, the lowering state may be actuated mechanically or by inflating the lowering chamber 8, causing the directed shaft 14 to shift to the left as shown in FIG. The pump can be switched off or not in this state when the oil coming from the pump enters the oil inlet (1) and passes to the tank (4) through the backstop (2) following the chamber (3) to the tank (4). Oil returning from the cylinder (18) passes from the connection to the cylinder (18) (5) to the tank through the connection to the tank (4).

The present invention is, of course, not in any way restricted to the embodiments described herein and a person of ordinary skill in the art may foresee many possibilities for modification thereof and substitution of technical characteristics for other equivalents, depending on the requirements of the invention. each situation as defined in the appended claims.

The described embodiments are obviously combinable with each other. The following dependent claims further define preferred embodiments of the present invention.

Claims

Single acting cylinder operation flow control valve comprising: a steering shaft movable between at least three positions; a central chamber for receiving the steering shaft; an oil inlet to receive oil from a hydraulic pump; a tank connection to return single acting cylinder oil to a tank; a cylinder connection for driving said cylinder, where the three positions of the steering shaft are:  a neutral position, in which the oil inlet and tank connection are connected together, and the cylinder connection is closed;  a rising position, wherein the oil inlet and cylinder connection are connected together;  a down position, wherein the cylinder connection and the tank connection are connected to each other. Flow control valve according to the preceding claim, wherein the steering shaft is coupled to the cylinder, or to a cylinder driven drive system, so that the cylinder end-stroke drives the steering shaft towards the cylinder. neutral position. Flow control valve according to any one of the preceding claims, comprising two pneumatic chambers for driving the steering shaft between two positions, the up position and the down position, in particular the directing shaft being coupled to a piston reciprocating in these two chambers, and more particularly the steering shaft is coupled coaxially to the piston. Flow control valve according to any one of the preceding claims, wherein in the down position, the oil inlet and tank connection are connected together to protect against the pump being turned off when descending. Flow control valve according to any one of the preceding claims, comprising a sensitive pressure limiter connected to the cylinder port for emptying the flow to the tank port in case of overpressure. Flow rate control valve according to the preceding claim, wherein the sensitive pressure limiter is connected to the cylinder connection when the cylinder connection is closed by the steering shaft and when it is connected to the oil inlet by the steering shaft. A flow direction valve according to the preceding claim, wherein the sensitive pressure limiter is configured to deflate flow to the tank connection to protect against bumps, oscillations, movement interruption, or combinations thereof. Flow control valve according to any one of the preceding claims, comprising a sensitive pressure limiter connected to the cylinder port for emptying the flow to the tank port in case of excess pressure. Flow control valve according to any one of the preceding claims, comprising a main pressure limiter connected to the oil inlet to empty the flow to the tank in case of overpressure. Flow control valve according to any one of the preceding claims, wherein the oil inlet comprises a non-return valve that prevents oil from returning to the pump. Flow control valve according to any one of the preceding claims, which comprises a positioning spring for returning the steering shaft to neutral position. Flow control valve according to any one of the preceding claims, which comprises a flange for direct attachment to the cylinder, in particular a standard flange, in particular SAE 61 or SAE 62 flange. Single acting cylinder interconnected to the flow control valve according to any one of the preceding claims. Single acting cylinder according to the preceding claim comprising an adapter flange for mounting the steering valve axially or transversely to the cylinder, in particular such that a cylinder end-stop cable acts the steering shaft towards the cylinder. neutral position as the cylinder moves angularly during tilting. An assembly comprising a flow direction valve according to any one of claims 1-12, a single acting cylinder interconnected to said direction valve mounted on said cylinder and a hydraulic pump interconnected to said flow direction valve.