The discharge valve unit includes: a valve case configured to be detachably attached to the housing and including a second reservoir for liquid configured to communicate with the first reservoir when the valve case is attached to the housing; and a second valve mechanism disposed in the second reservoir and including a second discharge hole having a larger opening diameter than that of the first discharge hole and a second valve member accommodated in the second reservoir and configured to open and close the second discharge hole. The second valve mechanism includes a spring configured to bias the second valve member in a valve opening direction. When a pressure of the second reservoir increases to a predetermined value, the second valve member closes the second discharge hole against a biasing force of the spring.

A state determination device for a liquid pumping apparatus includes: a casing that forms a reservoir space; a feed valve that introduces working gas into the reservoir space; an exhaust valve that releases the working gas from the reservoir space; and a valve operating mechanism having a float arranged in the reservoir space, and performing a pumping stroke in which the liquid is pumped from the reservoir space under a pressure of the working gas and an inflow stroke in which the liquid flows into the reservoir space and the working gas is released. The state determination device further includes a pressure sensor that detects a pressure of the reservoir space, and a determination unit that determines whether the liquid pumping apparatus is in an operating state of performing the pumping stroke or the inflow stroke based on the pressure detected by the pressure sensor.

A state determination device for a liquid pumping apparatus includes: a casing that forms a reservoir space; a feed valve that introduces working gas into the reservoir space; an exhaust valve that releases the working gas from the reservoir space; and a valve operating mechanism having a float arranged in the reservoir space, and performing a pumping stroke in which the liquid is pumped from the reservoir space under a pressure of the working gas and an inflow stroke in which the liquid flows into the reservoir space and the working gas is released. The state determination device further includes a pressure sensor that detects a pressure of the reservoir space, and a determination unit that determines whether the liquid pumping apparatus is in an operating state of performing the pumping stroke or the inflow stroke based on the pressure detected by the pressure sensor.

Disclosed is a deterioration determination device for a liquid pumping apparatus including: a casing that forms a reservoir space for storing liquid flowed thereto; a feed valve that introduces working gas into the reservoir space; an exhaust valve that releases the working gas from the reservoir space; and a valve operating mechanism having a float arranged in the reservoir space, and performing a pumping stroke in which the liquid is pumped from the reservoir space under a pressure of the working gas by opening the feed valve and closing the exhaust valve when the float moves up to a predetermined high level, and an inflow stroke in which the liquid flows into the reservoir space and the working gas is released from the reservoir space by closing the feed valve and opening the exhaust valve when the float moves down to a predetermined low level. The deterioration determination device includes a first pressure sensor arranged to communicate with a lower portion of the reservoir space to detect a pressure of a liquid layer in the reservoir space, and a deterioration determination unit that determines a degree of deterioration of the valve operating mechanism based on a change in the pressure detected by the first pressure sensor.

The discharge valve unit includes: a valve case configured to be detachably attached to the housing and including a second reservoir for liquid configured to communicate with the first reservoir when the valve case is attached to the housing; and a second valve mechanism disposed in the second reservoir and including a second discharge hole having a larger opening diameter than that of the first discharge hole and a second valve member accommodated in the second reservoir and configured to open and close the second discharge hole. The second valve mechanism includes a spring configured to bias the second valve member in a valve opening direction. When a pressure of the second reservoir increases to a predetermined value, the second valve member closes the second discharge hole against a biasing force of the spring.

A position detection sensor includes a rod-shaped contact part having a distal end and a proximal end, the contact part being configured such that an outer peripheral surface thereof at the distal end contacts an object and the contact part pivots about the proximal end in accordance with displacement of the object; a movable part configured to move with a pivot of the contact part; and a magnetic switch configured to sense a presence of the movable part and detect a position of the object when the movable part moves to approach a predetermined distance. The contact part is elastic and includes a columnar outer member constituting an outer peripheral portion of the contact part and a rod-shaped inner member inserted in the outer member and having an elastic modulus larger than that of the outer member.

A drain valve (10) includes a housing (11), a fluid inlet (12), a gas outlet (13) and at least one liquid outlet orifice (19) arranged in a liquid outlet member (20) of the housing (11). The drain valve (10) furthermore includes a float (16) connected to a lever (17) on a first end (18). The float (16) is arranged in a float chamber (15) of the housing (11). The float chamber (15) is connected to the fluid inlet (12), the gas outlet (13) and the at least one liquid outlet orifice (19). The liquid outlet orifice (19) may be opened or closed by a closing member (21) that is connected to a second end (22) of the lever (17) and is rotatably connected to the liquid outlet member (20).

A drain valve (10) includes a housing (11), a fluid inlet (12), a gas outlet (13) and at least one liquid outlet orifice (19) arranged in a liquid outlet member (20) of the housing (11). The drain valve (10) furthermore includes a float (16) connected to a lever (17) on a first end (18). The float (16) is arranged in a float chamber (15) of the housing (11). The float chamber (15) is connected to the fluid inlet (12), the gas outlet (13) and the at least one liquid outlet orifice (19). The liquid outlet orifice (19) may be opened or closed by a closing member (21) that is connected to a second end (22) of the lever (17) and is rotatably connected to the liquid outlet member (20).

A monitoring system is disclosed. The monitoring system comprises: a nozzle steam trap (3) including a supply portion (10) into which water vapor is supplied, and a discharge portion (11) which discharges liquid water contained in the water vapor; a temperature measurer (20) that measures a temperature of the discharge portion; a transmitter (24) that transmits temperature information containing the temperature measured by the temperature measurer; a receiver (7) that receives the temperature information; a determiner (8) that determines whether an abnormality is present in the nozzle steam trap based on the temperature information; and a notifier (9) that issues a notice when the determiner determines that the abnormality is present. A first discharge-side reference temperature lower than the boiling point of the water and a second discharge-side reference temperature higher than the boiling point of the water are set for the discharge portion. The determiner determines that the abnormality is present when the temperature of the discharge portion contained in the temperature information is lower than the first discharge-side reference temperature or higher than the second discharge-side reference temperature.

A position detection sensor includes a rod-shaped contact part having a distal end and a proximal end, the contact part being configured such that an outer peripheral surface thereof at the distal end contacts an object and the contact part pivots about the proximal end in accordance with displacement of the object; a movable part configured to move with a pivot of the contact part; and a magnetic switch configured to sense a presence of the movable part and detect a position of the object when the movable part moves to approach a predetermined distance. The contact part is elastic and includes a columnar outer member constituting an outer peripheral portion of the contact part and a rod-shaped inner member inserted in the outer member and having an elastic modulus larger than that of the outer member.