JPH0511359Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a pump that freely changes the amount of water delivered by moving a cover constituting a vortex chamber by an actuator, and in particular shortens the overall length and This invention relates to a pump that can reduce the operating force of the cover.

[Description of Prior Art] In conventional pumps for water-cooled engines, the maximum water flow rate of the pump is set to match the full-load operating range in which the engine releases the maximum amount of heat. Since the amount of water delivered by this pump is proportional to the number of revolutions of the pump, there is a drawback that in a partial load operating range, more water than necessary is circulated, resulting in wasted energy consumption.

On the other hand, there are systems that use a variable motor as a power source to adjust the amount of water delivered from the pump by changing the rotational speed of the pump or fan depending on the operating conditions. Variable motors for this purpose have not been put into practical use due to their high cost.

In order to improve this conventional drawback, the cover constituting the vortex chamber is moved by an actuator, thereby making it possible to vary the effective length of the vane and freely adjust the amount delivered from the pump. This was proposed in Utility Model Application No. 61-99033 by the applicant of the present application. This main structure is shown in cross section in FIG.

A volute chamber 16 is formed within the casing 10 and connects a fluid suction passage 12 and a fluid discharge passage 14 . A rotary shaft 18 is rotatably held within the casing 10. An impeller 22 having a plurality of integrally formed blades 20 is fixed to the end of the rotating shaft 18 on the spiral chamber 16 side.
The tip of the rotary shaft 18 is installed so as to extend beyond the rotating shaft 18. A cylindrical cover 24 with one end closed is attached from the tip side of the blade 20 so as to cover the blade 20 and the impeller 22. This cover 24 has a substantially conical end surface 2 for forming the wall surface of the spiral chamber 16.
6 and a cylindrical portion 28 having a cross-sectional shape that receives the outer edge of the impeller 22 at the outer edge of the end surface 26 thereof are integrally formed. A hole 30 is formed. This cover 24 is fixed to a sliding rod 32 which is a component of the actuator, and is slid in the direction of extension of the blade 20 depending on the operating situation. The blade 20 is set to always be inserted into the hole 30 of the cover 24 in any sliding position of the cover 24.

In this way, the cover 24 is moved by the actuator according to the operating condition of the engine, and the effective width of the blade 20 is adjusted to adjust the amount of water delivered.

[Problems to be solved by the invention] In a pump with a conventional configuration in which the cover 24 is inserted from the tip side of the blade 20 and the cover 24 is moved to adjust the effective width of the blade 20, the overall length of the pump is shortened. In order to do this, it is conceivable to utilize the space at the center of rotation of the blades arranged radially as shown in FIG. That is, by making the central portion, which is the center of rotation of the impeller 22, protrude toward the side where the blades 20 are attached, the lengths of the blades 20 and the rotating shaft 18 are made to overlap, and the overall length is shortened by the overlapped portion. I thought about that.

However, there is a limit to how much the central portion of the impeller 22 can protrude toward the extension side of the blades 20. This is because the aperture height cannot be increased by pressing the central part of the impeller 22, if the central part of the impeller 22 is too high, it will create resistance to the flow, and if the central part of the impeller 22 is made to protrude too high, it will cover the wall. For example, contact with the tip of the sliding rod 32 that holds the For these reasons, it was conventionally thought that the overall length of the pump could not be reduced much.

In addition, in the conventional configuration, when sliding the cover 24 in a direction that increases the effective length of the blade 20,
The volume of the space 34 between the impeller 22 and the end surface 26 of the cover 24 increases, and a negative pressure is generated in this space 34, and this negative pressure acts as resistance to the sliding direction of the cover 24. Furthermore, the water pressure from the vortex chamber 16 also provides resistance to the sliding direction of the cover 24. As described above, when the cover 24 slides, sliding resistance occurs due to both the negative pressure in the space 34 and the water pressure in the spiral chamber 16, resulting in the problem that the cover operation force must be increased. .

[Purpose of the invention] The present invention has been made in view of the above points.The length of the blade in the extending direction is within the range of the length position of the rotating shaft, and the cylindrical cover with one end closed is placed at the base of the blade. The purpose of this invention is to provide a pump which is inserted into the tip of the blade from the side, and which shortens the overall length of the pump and reduces the sliding resistance of the cover.

[Means for Solving the Problems] In order to achieve the above object, the present invention includes a casing in which a spiral chamber is formed, a rotary shaft that can be rotated freely within the casing, and a plurality of blades. an impeller fixed to the rotating shaft; a cylindrical cover with one end closed that engages with and rotates with the impeller and is slidable in the direction of extension of the blades of the impeller; and an actuator that adjusts the amount of sliding of the cover in the extension direction of the blade, the cover being engaged with the impeller so as to cover the blade from the root side to the tip side, and The blades are attached to the impeller with the tip side facing the direction of movement of the cover.

[Operation] The free tips of the impeller blades are arranged in the opposite direction to the cover. That is, the blades are arranged around the rotating shaft in the axial direction, so that the length of the blade in the extending direction is within the range of the length of the rotating shaft. This reduces the total length of the pump by omitting the length of the blade.

Further, a cylindrical cover with one end closed is inserted from the root side of the blade to the tip side of the blade, so that the open end of the cover projects into the spiral chamber. By this,
Water pressure in the swirl chamber acts on the cover in a direction that opposes the sliding resistance of the cover due to negative pressure or the like. Therefore, there is no sliding resistance when the cover slides.

[Example] Next, the present invention will be explained based on the drawings.

1 and 2 are cross-sectional views showing an embodiment of the pump according to the present invention. FIG. 1 shows a state where the discharge amount is minimum, and FIG. 2 shows a state where the discharge amount is close to the maximum. Inside this casing 40 is a bearing 4.
A rotating shaft 44 is rotatably provided via 2. A pulley 46 is fixed to the outer side of the casing 40 of the rotating shaft 44, and the pulley 46 is driven by a driving means (not shown) to rotate the rotating shaft 44. A suction passage 48 is provided in the casing 40 at a position close to the bearing 42,
A discharge passage 50 is provided adjacent to the suction passage 48, and a spiral chamber 52 is formed near the tip of the rotary shaft 44 to communicate with the suction passage 48 and the discharge passage 50 by going around the same.

An impeller 56 having a plurality of blades 54 integrally formed therein is fixed to one end of the rotating shaft 44 , and the blades 54 and the impeller 56 are housed in the spiral chamber 52 . As shown in the front view in FIG. 3, this impeller 56 has a shape having a plurality of radial protruding arms 58, and each of these protruding arms 58 has a blade 54 perpendicular to its outer edge on the rotation direction side. It is formed in one piece. The free tip of this blade 54 is similar to that shown in FIG.
As shown in the figure, it is arranged toward the bearing 42 side that holds the rotating shaft 44. That is, the blades 54 are arranged around the rotating shaft 44 in the axial direction, so that the length of the blades 54 in the extending direction is within the length of the rotating shaft 44. At the same time, the passages of the suction passage 48 and the discharge passage 50 are also connected to the rotation shaft 44 on the side surface of the rotation shaft 44.
Fit within the length range.

A cover 60 for adjusting the effective length of the blade 54 is shown in a longitudinal cross-sectional view in FIG. 4, and in a cross-sectional view taken along the line A--A in FIG. 4 in FIG. This cover 60
has a substantially conical closed end surface 62 and the impeller 56.
A cylindrical portion 6 with an inner wall cross-sectional shape capable of accommodating an external shape of
It consists of 4. The impeller 56 is inserted into the space 66 in the cylindrical part 64 of the cover 60 from the root side of the blade 54 toward the tip side of the blade 54, and during the sliding stroke of the cover 60, the impeller 56 is inserted into the space 66 in the cylindrical part 64 of the cover 60. 5
6 is set so that it does not deviate from this space 66.

The cover 60 is slid in the axial direction of the rotating shaft 44 by an actuator 68 depending on the operating situation. This actuator 68 is connected to a sliding rod 7 fixed at the center of rotation of the cover 60.
0, a diaphragm 72 fixed to the casing 40, an atmospheric chamber 74 and a negative pressure chamber 76 defined by the diaphragm 72, and a rod attached to the diaphragm 72 to rotatably hold the sliding rod 70. It consists of a rotation holding means 78 and a spring 80 provided in the negative pressure chamber 76 and urging the diaphragm 72 in a predetermined direction. The negative pressure chamber 7
6, negative pressure is introduced from a negative pressure introduction passage 82 according to the operating conditions, and the cover 60 is slid by the movement of the diaphragm 72 via the rotation holding means 78 and the sliding rod 70, The effective width of the blade 54 is adjusted.

In the pump configured as above, the cover 6
0 is arranged to cover the blade 54 from the root to the tip of the blade 54. That is, the edge of the open end of the cover 60 is located in the spiral chamber 52.
When the actuator 68 is actuated and the cover 60 moves from the minimum discharge amount state shown in FIG. 1 to the state where the discharge amount is close to the maximum amount shown in FIG. Pressure is generated, and a force that pulls the cover 60 toward the impeller 56 acts. Furthermore,
The back surface of the closed end surface 62 of the cover 60 and the casing 4
0 is compressed by the sliding movement of the cover 60, a force is applied to the cover 60 to press it toward the impeller 56. That is, cover 6
0, a resistance force opposite to the sliding direction (force pushing leftward in FIGS. 1 and 2) acts. On the other hand, the edge of the opening of the cylindrical portion 64 of the cover 60 has a spiral chamber 5.
When the pressure 2 is applied, the force that presses the cover 60 in the sliding direction (the force that presses it to the right in Figures 1 and 2)
It takes. As a result, the left and right forces applied to the cover 60 are canceled, and the actuator 6
8 does not cause any resistance to the operation of the cover 60.

[Effects of the invention] As described above, according to the pump according to the invention, the tip of the vane is directed in the opposite direction to the cover,
The length of the blade is kept within the installation length of the rotating shaft. This allows the overall length of the pump to be shortened by the length of the vane.

In addition, the cover that adjusts the effective length of the blade is inserted from the root of the blade toward the tip of the blade so that the open end of the cover is located in the spiral chamber. The sliding resistance is canceled out by the pressing force of the water in the spiral chamber. As a result, the operating force for the cover can be reduced compared to the conventional one.

[Brief explanation of drawings]

Figures 1 and 2 are cross-sectional views showing one embodiment of the pump according to the present invention. Figure 1 is a cross-sectional view showing a state where the discharge amount is at a minimum, and Figure 2 is a cross-sectional view showing a state where the discharge amount is close to the maximum. 3 is a front view of an impeller with blades, FIG. 4 is a longitudinal sectional view of the cover, FIG. 5 is a sectional view taken along line A-A of the cover shown in FIG. 4, and FIG. is a sectional view of a conventional pump. 40...Casing, 44...Rotating shaft, 54...
...Blade, 56...Impeller, 60...Cover, 62
. . . Closed end surface, 64 . . . Cylindrical portion, 68 . . . Actuator.

Claims (1)

[Scope of utility model registration request] A casing having a spiral chamber formed therein, a rotating shaft rotatably rotated within the casing, an impeller having a plurality of blades fixed to the rotating shaft, and engaging with the impeller. A pump consisting of a cylindrical cover with one end closed that rotates together with the impeller and is slidable in the direction of extension of the blades of the impeller, and an actuator that adjusts the amount of sliding of the cover in the direction of extension of the blades. , the cover is engaged with the impeller so as to cover the blade from the base side to the tip side, and the blade is attached to the impeller with the tip side of the blade facing the direction of travel of the cover. Features a pump.