Reciprocating pump

1. Field of the Invention

The present invention relates to a reciprocating pump.

2. Related Background Art

In a conventional reciprocating pump such as a plunger pump or a piston pump, a flow path inside a manifold curves in an approximately perpendicular direction between a suction port and a suction valve, and then curves in an approximately perpendicular direction between a discharge valve and a discharge port as described, for example, in Japanese patent No. 3983185.

Here, when the aforementioned reciprocating pump is operated, fluid sucked from the suction port flows along the flow path to a pump chamber and then is discharged from the pump chamber to the outside through the discharge port. However, at this time, the fluid passing through the inside of the manifold meets great resistance, which may result in problems such as noise or degradation of pump efficiency.

Furthermore, the shape of the manifold is complicated due to the complicated arrangement of the suction port, the suction valve, the discharge valve and the discharge port, and compact and lightweight design of the pump is therefore difficult.

The present invention was made to solve such problems and its object is to provide a reciprocating pump that has a compact and lightweight design and enables an improvement in pump efficiency and a reduction in noise.

The reciprocating pump of the present invention is a reciprocating pump for performing pumping in a pump chamber constituting an end of a cylinder by a reciprocating member reciprocating inside of the cylinder, and comprises: a manifold having the pump chamber; a suction port for sucking fluid from an outside to an inside of the manifold; a discharge port for discharging fluid from the inside to the outside of the manifold; a suction valve for opening and closing a flow path of the fluid to the pump chamber, the suction valve being provided between the suction port and the pump chamber; and a discharge valve for opening and closing a flow path of the fluid from the pump chamber, the discharge valve being provided between the pump chamber and the discharge port, the suction port, the suction valve, the discharge valve and the discharge port being arranged coaxially.

According to this reciprocating pump, since the suction port, the suction valve, the discharge valve and the discharge port are arranged coaxially, fluid flows without meeting unnecessary resistance, and therefore the fluid can be made to flow smoothly, pump efficiency can be improved, and noise can be reduced. Furthermore, as described above, since the suction port, the suction valve, the discharge valve and the discharge port are arranged coaxially, the structure of the manifold can be simplified and made compact and lightweight.

It is preferable that the manifold is fixed by a plurality of bolts to a casing accommodating a drive source side of the reciprocating member, and the bolts are mounted in equidistant positions on the same circumference viewed in a axial direction of the cylinder.

According to this reciprocating pump, since the configuration of the manifold is simplified by arranging the suction port, the suction valve, the discharge valve and the discharge port coaxially as described above, the degree of freedom of the arrangement of the plurality of bolts for fixing the manifold to the casing is increased, and the bolts can be mounted in equidistant positions on the same circumference viewed in the axial direction of the cylinder. The manifold can thereby be mounted to the casing in various rotational positions with a cylinder axis as a central axis, making installation of the reciprocating pump more convenient.

The reciprocating pump of the present invention enables an improvement in pump efficiency and a reduction in noise, with a compact and lightweight design.