An oil returning valve set with multi-stage throttling control includes an oil returning channel implemented in oil in an oil hydraulic equipment. The two ends of the oil returning channel are connected to a pressurized oil collecting cavity and a pressurized oil discharging cavity respectively. A plurality of throttling valve plugs and oil returning valve plug are arranged in the oil returning channel, and a normally-open draining gap is also formed among the plurality of throttling valve plugs. When the oil returning valve plug is opened, a plurality of the throttling valve plugs are arranged in series to generate multi-stage throttling oil hydraulic draining control, which improves the problem that the valve opening allowance of the throttling valve for oil returning and pressure relief of traditional oil hydraulic equipment is not sufficient.

Pressure valve for a liquid comprising a housing with an inlet and an outlet for directing the liquid from the inlet through the housing to the outlet along a flow direction, wherein valve further comprises movable member which is movable in the housing towards and away from the outlet between a blocked position wherein the movable member blocks the outlet and an unblocked position wherein the movable member is moved away from the outlet in a direction opposite the flow direction.

A pressure reducing valve includes a piston disposed in a cylinder chamber; a valve element that is coupled to the piston and opens and closes a valve seat; a valve spring that biases the valve element in a direction in which the valve element is moved away from the valve seat; and a biasing member that biases the valve seat toward a side opposite to the piston. The pressure reducing valve is configured to reduce a primary pressure of a fluid to a secondary pressure. The valve seat is disposed such that the valve seat reciprocates in the same direction as a direction in which the valve element reciprocates in the primary pressure chamber. As a difference between the primary pressure and the secondary pressure increases, the valve seat moves toward the secondary pressure chamber.

An oil returning valve set with multi-stage throttling control includes an oil returning channel implemented in oil in an oil hydraulic equipment. The two ends of the oil returning channel are connected to a pressurized oil collecting cavity and a pressurized oil discharging cavity respectively. A plurality of throttling valve plugs and oil returning valve plug are arranged in the oil returning channel, and a normally-open draining gap is also formed among the plurality of throttling valve plugs. When the oil returning valve plug is opened, a plurality of the throttling valve plugs are arranged in series to generate multi-stage throttling oil hydraulic draining control, which improves the problem that the valve opening allowance of the throttling valve for oil returning and pressure relief of traditional oil hydraulic equipment is not sufficient.

A flow regulating valve and a compressor with the flow regulating valve are disclosed. The flow regulating valve includes: a valve seat in which a passage is formed to allow fluid to enter; a guide member protruded outwards from the valve seat; a piston which is disposed on the outside of the valve seat, forms a fluid inlet with the valve seat, and is capable of being reciprocated along the guide member; and a biasing member biasing the piston in a direction away from the valve seat. A force exerted by the incoming fluid on the piston is opposite in direction to a biasing force exerted by the biasing member on the piston. The piston is able to be moved to different positions under the action of different forces to form fluid inlets of different widths with the valve seat, thereby controlling the mass flow rate of the incoming fluid (especially liquid). With the technical solutions of the present invention, the flow rate of the fluid entering the compressor can be effectively adjusted with a simple structure and low cost.

A check valve assembly includes a valve, cam and arm with float rotatably connected to the valve for insertion into a fluid storage container for filling of the container without overfilling. The valve includes a channel of narrowing diameter and restricting member movably retained within the channel. One end of the restricting member rides along the cam profile as the arm rotates the cam with the changing fluid levels. When the fluid reaches maximum fill level, the restricting member contacting the cam drops into the cam valley, driving the restricting member head into engagement with the channel neck walls and automatically sealing off the valve. First and second biasing members are disposed in the channel, preferably around the stem, and collectively provide counter force sufficient to overcome the frictional forces of the seal to open valve and move the restricting member upward.

A self-acting pressure activated drain valve includes at least one inlet configured to receive a fluid. A drainage passage delivers the fluid to at least one outlet where the fluid is expelled. The self-acting pressure activated drain valve further includes a flexible diaphragm configured to operate in an open position and a closed position based on a pressure. The flexible diaphragm is normally biased in the open position such that fluid is delivered from the at least one inlet to the at least one outlet via the drainage passage. The pressure, however, initiates the closed position such that air is prevented from flowing through the drainage passage.

A pressure reducing valve includes a piston disposed in a cylinder chamber; a valve element that is coupled to the piston and opens and closes a valve seat; a valve spring that biases the valve element in a direction in which the valve element is moved away from the valve seat; and a biasing member that biases the valve seat toward a side opposite to the piston. The pressure reducing valve is configured to reduce a primary pressure of a fluid to a secondary pressure. The valve seat is disposed such that the valve seat reciprocates in the same direction as a direction in which the valve element reciprocates in the primary pressure chamber. As a difference between the primary pressure and the secondary pressure increases, the valve seat moves toward the secondary pressure chamber.

A self-sealing safety valve (10) for a container of pressurised fluid (12) comprises a substantially solid body (14) and attachment means (24) for connecting to a dispensing valve. The self-sealing safety valve includes a substantially central bore (16) extending through both the attachment means and the solid body, and the bore connects an inlet (20) to an outlet (18). The bore comprises at least three parts each of a different diameter: a first part (16a) immediately adjacent the outlet has a first diameter; a second part (16b) located immediately adjacent the first part has a second diameter that is wider diameter than the first diameter; and a third (16c) part located immediately adjacent the second part has a third diameter that is wider than the second diameter. The second part of the bore houses a first biasing means (30). The third part of the bore houses a sealing ball (28) and a second biasing means (38), and the sealing ball is located between the first and second biasing means. The diameter of the sealing ball is greater than the first diameter but smaller than the second diameter and is capable of sealing the second part of the bore. Under normal flow conditions of fluid through the bore, the first biasing means is configured to bias the sealing ball away from the second part of the bore. Under conditions of high pressure fluid flow through the bore, the sealing ball is forced towards a junction (21) between the second and third parts of the bore, against the first biasing means, sealing the outlet.

A check valve assembly includes a valve, cam and arm with float rotatably connected to the valve for insertion into a fluid storage container for filling of the container without overfilling. The valve includes a channel of narrowing diameter and restricting member movably retained within the channel. One end of the restricting member rides along the cam profile as the arm rotates the cam with the changing fluid levels. When the fluid reaches maximum fill level, the restricting member contacting the cam drops into the cam valley, driving the restricting member head into engagement with the channel neck walls and automatically sealing off the valve. First and second biasing members are disposed in the channel, preferably around the stem, and collectively provide counter force sufficient to overcome the frictional forces of the seal to open valve and move the restricting member upward.