JPH0622159Y2 - pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a pump in which a cover forming a spiral chamber can be moved by an actuator to freely change the amount of water to be delivered, and in particular, it is formed by the cover. The present invention relates to a pump configured to reduce a negative pressure generated in a space.

[Description of Prior Art] In a conventional water-cooled engine pump, the maximum amount of water in the pump is set so as to match the full-load operating range in which the maximum amount of heat of the engine is discharged. Since the amount of water delivered from the pump is proportional to the number of revolutions of the pump, there is a disadvantage in that more water than necessary circulates in the partial load operation range, resulting in wasted energy consumption.

On the other hand, for example, a variable motor is used as a power source and the number of pumps or fans is changed according to operating conditions to adjust the amount of water delivered from the pump. The variable motors that can be used have not been put into practical use because they are expensive.

As an improvement of this conventional drawback, a cover which constitutes a spiral chamber is moved by an actuator so that the amount of delivery from a pump can be freely adjusted, as disclosed in Japanese Patent Application No. 61-99033 by the present applicant. Proposed by. FIG. 3 shows a state in which the amount of delivered water is minimum in the configuration in which the cover is directly connected to the actuator based on this configuration, and FIG. 4 shows a state in which the delivered water amount is maximum.

In the casing 10, a fluid inlet 12 and a fluid outlet 14 are provided.
A vortex chamber 16 that communicates with the is formed. A rotary shaft 18 is rotatably provided in the casing 10, and the rotary shaft 18 is rotated by a driving means (not shown). A plurality of blades 20 are provided on the side of the rotary shaft 18 on the side of the spiral chamber 16.
The impeller 22 integrally formed with is fixed. An annular skirt portion 24 parallel to the rotary shaft 18 is integrally formed on the outer edge of the impeller 22.

A cover 26 that slides in the axial direction of the rotary shaft 18 is attached to the impeller 22. The cover 26 is formed by integrally forming an arcuate surface 28 for forming the wall surface of the spiral chamber 16 and an annular skirt portion 30 slidably contacting the outer side of the skirt portion 24 on the outer edge of the arcuate surface 28. It is a thing. A plurality of holes 32 for inserting the blades 20 are formed on the arcuate surface 28 (FIG. 5). The blades 20 of the impeller 22 are inserted into the holes 32,
Each of these vanes 20 has a hole 32 during the stroke of the cover 26.
It is designed not to come off. A space 34 is formed between the cover 26 and the impeller 22, and the volume of the space 34 changes as the cover 26 slides. At this time, the blades 2 of the holes 32 of the cover 26 enter the space 34.
Water flows in and out through the gap between 0 and 0.

An actuator 3 having a rod 36 fixed to the center of the cover 26 and a rotation holding means 37 for sliding the rod 36 while keeping the rotation of the rod 36 in the casing 10.
8 is attached. The actuator 38 slides the cover 26 via the rod 36 by negative pressure or the like. When the cover 26 is pulled toward the spiral chamber 16 side by the actuator 38, the amount of water supply is minimized (the state shown in FIG. 3), and when the blades 20 are protruded from the holes 32 of the cover 26 to the maximum. The amount of delivered water becomes maximum (state of FIG. 4).

Thus, the actuator 26 causes the cover 26 to
Is moved to adjust the effective width of the blades, and the amount of water supply is adjusted according to the operating conditions of the engine.

[Problems to be Solved by the Invention] When the pump is operated, the water filled in the space 34 between the cover 26 and the impeller 22 is generated by the action of the centrifugal force of rotation of the blades 20. It is discharged from 32 to the outside of the space 34. As a result, negative pressure is generated in the space portion 34, and a force that pulls the cover 26 toward the space portion 34 acts due to this negative pressure. Particularly, as the rotation speed of the blade 20 increases, the negative pressure in the space 34 increases. Further, the larger the volume of the space 34, the larger the force acting on the cover 26. Therefore, in order to operate the cover in a predetermined manner, the operating force of the actuator must be increased.

[Object of the Invention] The present invention has been made in view of the above-mentioned points, and in the space between the impeller and the cover, the resistance to the actuator that operates the cover is reduced by reducing the area where negative pressure is applied. The object is to provide a pump that reduces the force.

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present invention comprises a casing in which a spiral chamber is formed, an impeller attached to a rotary shaft,
A plurality of blades attached to the impeller, a cover facing the spiral chamber and having a hole through which the blade is inserted, the cover being slidably mounted in the axial direction of the rotating shaft, and the swirl of the cover. A pump having an actuator having a sliding means for adjusting the amount of protrusion movement toward the shaping chamber, wherein a space is formed between the cover and the impeller, in a first cylinder part on the space side of the cover. A second tubular portion is formed on the space side of the impeller, and the first tubular portion and the second tubular portion are fitted and engaged so as not to come off during the entire stroke of the cover. Is.

[Operation] A chamber is formed in the space by the cover-side cylinder and the impeller-side cylinder so that negative pressure does not reach the chamber during the entire stroke of the cover. As a result, the area of the space where negative pressure is applied is narrowed, and the resistance force to actuating the actuator is reduced.

[Embodiment] Next, the present invention will be described with reference to the drawings.

1 and 2 are sectional views showing an embodiment of the pump according to the present invention, and FIG. 1 shows a state in which the amount of delivered water is minimum,
FIG. 2 shows a state in which the amount of delivered water is maximum. In FIGS. 1 and 2, the same reference numerals as those in FIGS. 3 and 4 described above indicate the same parts.

A cover 40 is attached to the tip of the actuator 38, and the cover 40 is displaced by the operation of the actuator 38. On the space portion 34 side of the cover 40, a cylindrical first tubular portion 42 centered on the rotation center position is formed. On the other hand, on the space portion 34 side of the impeller 44, an arc-shaped second cylinder portion 46 centered on the rotation center position is formed. The inner diameter of the first tubular portion 42 and the outer diameter of the second tubular portion 46 are in a fitting relationship. Then, within the entire stroke range of the cover 40, the inside of the first tubular portion 42 is always fitted to the outside of the second tubular portion 46, and the axial length of the first tubular portion 42 and the length of the second tubular portion 46. Is set. The first cylinder portion 42, the second cylinder portion 46, the cover 40, and the impeller 22 form a chamber 48.
Is formed. The gap from the chamber 48 to the space 34 is very narrow. Further, the hole 32 does not reach the chamber 48. When the pump is stopped, the chamber 48 has a first tubular portion 42 and a second tubular portion 46.
The fluid in the space 34 gradually flows in from the fitting gap with (in use, water is generally filled).

The fitting between the first tubular portion 42 and the second tubular portion 46 may be a fitting relationship between the outer diameter of the first tubular portion 42 and the inner diameter of the second tubular portion 46.

With the above configuration, when the pump operates and the blades 20 rotate, the water in the space portion 34 is discharged from the hole 32 of the cover 40, and the space portion 34 excluding the chamber 48 is in a negative pressure state. Becomes However, since the chamber 48 provided in the space 34 is filled with water, and the gap leading from the chamber 48 to the space 34 is very narrow, a negative pressure does not reach the chamber 48.

[Advantage of the Invention] As described above, according to the pump of the present invention, a region to which negative pressure is not applied is formed in the space formed by the cover and the impeller. Therefore, it is possible to reduce the area to which the negative pressure is applied as compared with the conventional space portion to reduce the resistance applied to the actuator, and to make the actuator have a smaller operating force than the conventional one.

Further, since the first cylindrical portion of the cover and the second cylindrical portion of the impeller are in a fitting relationship, it is possible to serve also as centering between the cover and the impeller.

[Brief description of drawings]

1 and 2 are cross-sectional views showing an embodiment of the pump according to the present invention. FIG. 1 is a cross-sectional view showing a state in which the amount of delivered water is minimum, and FIG. 2 is a state in which the amount of delivered water is maximum. Sectional drawing, FIG. 3 is a sectional view showing a state in which a conventional pump delivers a minimum amount of water, FIG. 4 is a sectional view showing a state in which a conventional pump delivers a maximum amount of water, and FIG. 5 is a front view of a cover. is there. 10 ... Casing, 16 ... Vortex chamber, 18 ... Rotating shaft, 20 ... Blade, 32 ... Hole, 34 ... Space part, 36 ... Sliding rod, 38 ... Actuator, 40 ... Cover , 42 ... first cylinder part, 44 ... impeller, 46 ... second cylinder part, 48 ... chamber.

Claims (1)

[Scope of utility model registration request] 1. A casing having a volute chamber formed therein, an impeller attached to a rotating shaft, a plurality of vanes attached to the impeller, and a vane facing the volute chamber. A cover having a hole formed therein and attached slidably in the axial direction of the rotary shaft; and an actuator having a sliding means for adjusting a protruding movement amount of the cover toward the volute-shaped chamber. In a pump in which a space is formed between the impeller, a first cylinder is formed on the space side of the cover, and a second cylinder is formed on the space side of the impeller. The pump and the second cylinder are fitted and engaged so as not to come off during the entire stroke of the cover.