KR102453608B1 - A gear pump - Google Patents

Abstract

The gear pump is started. A gear pump according to an embodiment of the present invention includes: a casing in which an inlet and an outlet are formed; a driving gear rotatably installed around a driving shaft in the casing; and a driven gear meshed with the driving gear in the casing and rotatably installed about a driven shaft by rotation of the driving gear, wherein when the driving gear and the driven gear rotate, the driving gear and the driven gear The angle between the trajectory drawn by the end of the gear teeth of the first straight line simultaneously contacting the suction port and the second straight line contacting the inner wall of the casing while passing the point where the first straight line meets the trajectory is 5 to 30 degrees.

Description

Gear Pump {A GEAR PUMP}

The present invention relates to a gear pump for pumping a fluid.

The gear pump is installed inside the casing so that the mutual teeth of the driving gear and the driven gear are meshed with each other. Fluid is supplied to one side of the casing, and the driving gear drives the driven gear to rotate while meshing with each other to pump the fluid to flow to the other side of the casing. That is, the gear pump puts a pump gear consisting of a driving gear and a driven gear that mesh with each other in a casing circumscribed thereto, and rotates the driving gear and the driven gear to flow the fluid through the space formed between the groove of the gear tooth and the inner wall of the casing. It is structured to make

However, pressure pulsation is generated when the gear pump pumps the fluid. Pulsation refers to a change in the pressure of the fluid discharged from the gear pump. As the magnitude of the pulsation generated during pumping of the gear pump increases, internal shock and vibration are generated in the device receiving the fluid from the gear pump, and the durability of the device receiving the fluid There is a problem in that it adversely affects the gear pump and generates noise when pumping the gear pump.

An object of the present invention is to provide a gear pump capable of reducing pulsation in order to solve the problems of the prior art.

In order to solve the above problems, an embodiment of the present invention includes a casing in which an inlet and an outlet are formed; a driving gear rotatably installed around a driving shaft in the casing; and a driven gear meshed with the driving gear in the casing and rotatably installed by rotation of the driving gear, wherein when the driving gear and the driven gear rotate, the end of the gear teeth of the driving gear and the driven gear The angle between the drawing trajectory and the first straight line in contact with the suction port at the same time and the second straight line in contact with the inner wall of the casing while passing the point where the first straight line meets the trajectory may provide a gear pump of 5 to 30 degrees. .

In this case, the angle may be 10 degrees to 15 degrees.

In addition, the ratio of the width to the outer diameter of the driving gear and the driven gear may be 1.76 to 2.10.

In addition, the ratio of the width to the outer diameter of the driving gear and the driven gear may be 1.91.

According to one embodiment of the present invention, the suction angle is set within the range of 5 to 30 degrees, there is an effect that the generation of pulsations is reduced.

In addition, according to an embodiment of the present invention, since the suction angle is set within the range of 10 to 15 degrees, there is an effect that the generation of pulsations is reduced as much as possible.

In addition, according to an embodiment of the present invention, since the ratio of the width to the outer diameter of the gear is set within the range of 1.76 to 2.10, the generation of pulsations is reduced and the pump efficiency is improved.

In addition, according to an embodiment of the present invention, since the ratio of the width to the outer diameter of the gear is set to 1.94, the generation of pulsations is reduced to the maximum and the pump efficiency is maximized.

1 is a view showing the overall internal structure of a gear pump according to an embodiment of the present invention.
2 is a plan view of a gear of a gear pump according to an embodiment of the present invention.
3 is a side view of a gear of a gear pump according to an embodiment of the present invention.
4 is a graph showing the pulsation according to the change of the suction angle in the gear pump according to the embodiment of the present invention.
5 is a graph illustrating flow rate/torque and pulsation according to a change in a ratio of a width to an outer diameter of a gear of a gear pump according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in adding reference numerals to the components of each drawing, it should be noted that the same components are given the same reference numerals as much as possible even though they are indicated on different drawings. In the description of the present embodiment, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present embodiment, the detailed description thereof will be omitted.

1 is a view showing the overall internal structure of a gear pump according to an embodiment of the present invention. 2 is a plan view of a gear of a gear pump according to an embodiment of the present invention, and FIG. 3 is a side view of a gear of a gear pump according to an embodiment of the present invention.

As shown in FIG. 1 , the gear pump 10 according to an embodiment of the present invention includes a casing 20 , an inlet 22 , an outlet 28 , a driving gear 30 , and a driven gear 40 . can do.

The casing 20 accommodates the driving gear 30 and the driven gear 40 therein, and provides a space in which the fluid can be pumped. At one side of the casing 20, a suction port 22 through which the fluid flows into the casing 20 from the outside is formed. On the other side of the casing 20, that is, on the opposite side of the side where the suction port 22 is formed with the driving gear 30 and the driven gear 40 interposed therebetween, the pumped fluid is discharged to the outside of the casing 20 A discharge port 28 is formed In this embodiment, the fluid flows into the casing 20 in a direction intersecting the plane on which the driving gear 30 and the driven gear 40 are placed, and the pumped fluid is the driving gear 30 and the driven gear 40. It can be discharged parallel to the plane on which it is placed. If necessary, the fluid may be introduced into the casing 20 in a direction perpendicular to a plane on which the driving gear 30 and the driven gear 40 are placed. Between the suction port 22 and the driving gear 30 and the driven gear 40, the fluid introduced into the casing 20 passes through to flow toward the driving gear 30 and the driven gear 40. The suction part ( 24) and a discharge unit 26 that is a region through which the fluid pumped by the driving gear 30 and the driven gear 40 passes before being discharged through the discharge port 28 may be provided.

The driving gear 30 and the driven gear 40 are rotatably installed around the driving shaft 32 and the driven shaft 42 inside the casing 20 , respectively. The driving gear 30 is configured to pump the fluid and at the same time provide a rotational force to the driven gear 40 . The driving gear 30 may be installed inside the casing 20 with the driving shaft 32 as a rotation center. The driven gear 40 is rotated by the rotational driving of the driving gear 30 to pump the fluid. The driven gear 40 is disposed to mesh with the driving gear 30 inside the casing 20 , and may be rotated by the rotation of the driving gear 30 with the driven shaft 42 as a rotation center.

When the driving gear 30 is rotated by the driving means, the driven gear 40 meshed with the driving gear 30 rotates in the opposite direction to the driving gear 30, thereby discharging the liquid introduced through the suction port 22 through the discharge port 28. A pumping action of pumping to the side is made. In the gear pump 10 according to an embodiment of the present invention, the driving gear 30 rotates counterclockwise and the driven gear 40 rotates clockwise, thereby discharging the fluid from the suction unit 24 side to the discharge unit 26 ) to the side of the pump. However, the rotation direction of the driving gear 30 and the driven gear 40 may vary depending on the positions of the suction unit 24 and the discharge unit 26 , and the arrangement of the driving gear 30 and the driven gear 40 .

The driving gear 30 and the driven gear 40 may have the same structure and dimensions. That is, the driving gear 30 and the driven gear 40 may have the same outer diameter, width, and number of gear teeth. Hereinafter, the driving gear 30 and the driven gear 40 are referred to as gears 30 and 40 for convenience.

Factors affecting the pulsation generated during pumping of the gear pump include the outer diameter D1, the width W1, and the suction angle θ1 of the gears 30 and 40. The gear pump 10 according to an embodiment of the present invention can reduce the pulsation phenomenon by optimizing these factors.

First, the effect of the suction angle θ1 on the pulsation will be examined. Referring to FIG. 1 , the suction angle θ1 may be defined as follows. When the gears 30 and 40 are rotated, the trajectory drawn by the end of the gear teeth and the first straight line in contact with the suction port 22 at the same time are referred to as L1, and the first straight line L1 passes through the point where the trajectory meets the trajectory, and the inner wall of the casing 20 When the second straight line tangent to (29) is L2, the angle between the first straight line L1 and the second straight line L2 can be defined as the suction angle θ1. The suction angle θ1 may be equally applied to the driving gear 30 side and the driven gear 40 side.

In a typical gear pump, the suction angle θ1 is set to almost 0 degrees. When the suction angle θ1 is set to 0 degrees, the fluid does not smoothly flow into the space between the gears 30 and 40 and the inner wall of the casing 20, so that the possibility of pulsation increases. On the other hand, even when the suction angle θ1 becomes larger than an appropriate degree, the pulsation performance may be deteriorated.

4 is a graph illustrating pulsation according to a change in a suction angle in a gear pump according to an embodiment of the present invention. As shown in FIG. 4 , it can be seen that the generation of pulsations is suppressed when the suction angle θ1 is 5 degrees to 30 degrees. In addition, it can be confirmed that the generation of pulsation is best suppressed when the suction angle θ1 is 10 degrees to 15 degrees. Therefore, in this embodiment, the suction angle θ1 for each of the driving gear 30 and the driven gear 40 side may be set to 5 degrees to 30 degrees, and when set to 10 degrees to 15 degrees, optimal pulsation performance is obtained. can perform

Next, the influence of the outer diameter D1 and the width W1 of the gears 30 and 40 on the pulsation will be examined. The outer diameters D1 and widths W1 of the gears 30 and 40 may be variously changed according to performance conditions required for the gear pump. However, by adjusting the ratio (D1/W1) of the width W1 to the outer diameter D1 of the gears 30 and 40, the pulsation can be significantly reduced.

5 is a graph illustrating flow rate/torque and pulsation according to a change in a ratio of a width to an outer diameter of a gear of a gear pump according to an embodiment of the present invention. 5, when the ratio (D1/W1) of the width W1 to the outer diameter D1 of the gears 30 and 40 is 1.76 or more and 2.10 or less, it can be confirmed that the flow rate per torque is high and the pulsation pressure is low have. A high flow rate per torque means that a large flow rate can be generated with a small torque, which means that the efficiency of the gear pump is high. On the other hand, when the ratio (D1/W1) of the width W1 to the outer diameter D1 of the gears 30 and 40 exceeds 2.10, it can be seen that the flow rate per torque drops sharply and the pulsation pressure also rises. Accordingly, in the present embodiment, the ratio (D1/W1) of the width W1 to the outer diameter D1 of the gears 30 and 40 may be 1.76 to 2.10. 5, when the ratio (D1/W1) of the width W1 to the outer diameter D1 of the gears 30 and 40 is 1.91, the generation of pulsation is reduced to the maximum and the pump efficiency is maximized can be improved

Table 1 below shows the results of testing the flow rate, torque, and pulsation pressure of the fluid according to various dimensions of the gears 30 and 40.

number Gear outer diameter (D1) [mm] Gear width (W1) [mm] Ratio of width to outer diameter (D1/W1) Suction angle (θ1)
[do] flux
[ℓ/min] talk
[Nm] pulsation
[bar] One 44 19 2.32 0 56.2 4.6 1.9 2 44 21 2.10 10˚ 66.6 5.0 1.1 3 44 23 1.91 20˚ 72.3 5.4 1.2 4 56.8 14 4.06 20˚ 71.7 6.5 1.3 5 56.8 16 3.55 0 68.3 6.4 2.5 6 59 12.5 4.72 10˚ 70.5 7.2 1.5 7 59 14.5 4.07 20˚ 82.2 7.7 1.6 8 59 16.5 3.58 0 83.5 9.1 3.5

As can be seen in Table 1, when the ratio (D1/W1) of the width W1 to the outer diameter D1 of the gears 30 and 40 is 2.10 or less, it can be seen that the pulsating pressure is low and the flow rate per torque is high. . In addition, it can be seen that the pulsation pressure is low when the suction angle θ1 is between 10 degrees and 15 degrees.

As such, the gear pump 10 according to an embodiment of the present invention sets the suction angle θ1 between 10 degrees and 15 degrees, and the width W1 with respect to the outer diameter D1 of the gears 30 and 40. By setting the ratio (D1/W1) to 1.76 to 2.10, it is possible to suppress the pulsation as much as possible and to improve the pump efficiency.

The above description is merely illustrative of the technical idea of the present invention, and various modifications, changes and substitutions will be possible without departing from the essential characteristics of the present invention by those of ordinary skill in the art to which the present invention pertains. . Accordingly, the present embodiment is intended to explain, not to limit the technical spirit of the present invention, and the scope of the technical spirit of the present invention is not limited by these embodiments. The protection scope of the present invention should be construed by the following claims, and all technical ideas within the equivalent range should be construed as being included in the scope of the present invention.

10: gear pump 20: casing
22: suction port 24: suction unit
26: discharge unit 28: discharge port
30: drive gear 32: drive shaft
40: driven gear 42: driven shaft
D1: outer diameter of gear W1: width of gear
θ1: suction angle

Claims (4)

a casing in which the inlet and outlet are formed;
a driving gear rotatably installed around a driving shaft in the casing; and
and a driven gear meshed with the driving gear in the casing and rotatably installed about a driven shaft by rotation of the driving gear,
The casing is
A portion of the inner wall of the casing between the driving gear and the suction port is recessed in a direction away from the trajectory drawn by the ends of the gear teeth of the driving gear and the driven gear when the driving gear and the driven gear rotate,
The angle between the first straight line in contact with the trajectory and the suction port at the same time and the second straight line in contact with a region of the inner wall of the casing recessed while passing a point where the first straight line meets the trajectory is 5 degrees to 30 degrees gear pump. According to claim 1,
The angle is 10 degrees to 15 degrees gear pump. According to claim 1,
The ratio of the width to the outer diameter of the driving gear and the driven gear is 1.76 to 2.10 of the gear pump. 4. The method of claim 3,
The ratio of the width to the outer diameter of the driving gear and the driven gear is 1.91.

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