JP4044980B2 - pump - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a pump for supplying fluid to a consuming device.
[0002]
[Prior art]
In the case of the types of pumps mentioned here, there is a problem that negative pressure may occur in the suction area. This negative pressure causes cavitation, which on the one hand generates loud noise and on the other hand can cause damage.
[0003]
[Problems to be solved by the invention]
The object of the present invention is to construct a pump without these disadvantages.
[0004]
[Means for Solving the Problems]
In order to solve the above-mentioned problems, the present invention provides a pump for supplying a fluid to a consuming device, wherein the fluid in a state of receiving pressure returned from the consuming device to pressurize the suction chamber. in the pump so as to use, the wall portion that separates the suction chamber of the pump from the suction connection part is provided, said wall portion, flow through the suction connection section by narrowing the suction connection section in the transition region to the suction chamber Oil collection by separating the suction connection portion and the suction chamber so that the first function of accelerating the fluid and the transition region between the suction connection portion and the suction chamber are positioned above the oil collection chamber. it has a second function of securing the chamber in communication with the working pressure side of the pump, the pressure discharge portion of the press section is also to be located upward enough to ensure oil collecting chamber Characterized by being placed in Is shall. The pump suction chamber is pressurized by the fluid under pressure returned from the consumption device, that is, the overpressure fluid is supplied to the suction chamber, thereby ensuring the cavitation action. Can be prevented. Also, by providing the wall portion , it is possible to accelerate the flow of the fluid flowing through the suction connection portion, and to prevent the pump chamber from becoming empty when the pump is stopped, so that the pump can be started better. Behavior occurs. Furthermore, the communication part (transition area) between the suction connection part and the suction chamber and the pressure discharge part in the pressurization area, which is in communication with the working pressure side of the pump, are located above the oil collection chamber. The starting characteristics of the pump are further improved.
[0005]
The present invention can be used for, for example, a roller-type rotary pump, a blade-type rotary pump, and a gear rotary pump.
The following embodiments of the present invention are advantageous. That is, in this embodiment, the fluid returned from the consuming device, is sent into the pressure chamber having a pressure chamber outlet is open to the suction chamber of the pump. The cross section of the pressure chamber outlet is smaller than the cross section of the reflux connection that guides the fluid returned from the consuming device to the pressure chamber. With this arrangement, the guided fluid is accelerated as it flows out through the pressure chamber outlet. Therefore, the fluid that flows into the suction chamber at a relatively high speed can entrain the fluid in the suction chamber and supply it to the suction region of the pump.
[0006]
Furthermore, the following embodiment of the pump is advantageous. That is, in this embodiment, the cross section of the suction chamber is larger than the cross section of the pressure chamber discharge port. By the energy conversion by the fluid, the pressure in the suction chamber is increased by the fluid flowing out from the pressure chamber outlet at a high speed. This increased pressure contributes to preventing cavitation in the suction area of the pump.
[0008]
Other configurations are described in other dependent claims.
[0009]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be described in detail below with reference to the drawings.
The present invention relates to a gear pump, a roller-type rotary pump, and a blade-type rotary pump. In the following, a vane rotary pump is described purely as an example. However, the pressurizing means in the suction region of the blade-type rotary pump described here can also be input in the case of a roller-type rotary pump and a gear pump.
[0010]
A blade-type rotary pump 1 shown in FIG. 1 has a rotor 3. A slit 5 extending in the radial direction is provided in the peripheral wall portion of the rotor 3, and the slit 5 receives the movable blade 7 in the radial direction.
[0011]
The rotor 3 is rotatably arranged in a contour ring 9 (Konturring). The inner surface 11 of the contour ring 9 is formed in such a way that two transport chambers 13 and 15 are formed which are located facing each other and in this case are identically formed. Their carrying chambers 13 and 15 are approximately crescent shaped. When the rotor 3 rotates inside the contour ring 9, the blades in the slit come in and out. As a result, a suction area and a pressure area are formed in the transport chambers 13 and 15. When the rotor 3 rotates, two suction areas 17 and 19 that face each other and two pressure areas 21 and 23 that face each other are generated. Their arrangement shown in FIG. 1 is given during the counterclockwise rotation of the rotor.
[0012]
The contour ring 9 is inserted into the pump casing 25, and the suction connection portion 27 opens inside the pump casing 25. A connecting portion that leads to the tank is connected to the suction connection portion 27. The tank is introduced with fluid, possibly under slightly pressure, returned from the consuming device. The suction connection is in communication with a suction chamber 29 that substantially completely surrounds the contour ring 9. Suction chamber 29 is fluidly coupled to pump suction areas 17 and 19. The suction chamber 29 is closed by a packing pad 31 at the end opposite to the suction connection portion 27. A pressure chamber 33 is located on the opposite side of the packing pad. The pressure chamber 33 is limited on the one hand by the casing 25 and on the other hand by the contour ring 9 and has a pressure chamber outlet 35 to the suction chamber 29. A reflux connection portion 37 is opened in the pressure chamber 33, and the fluid under pressure reaches the vane-type rotary pump 1 from the consumption device via the reflux connection portion 37. The cross section of the reflux connection is much larger than the cross section of the pressure chamber outlet 35.
[0013]
It can be seen from FIG. 1 that the wall portion 39 is located between the pressure chamber 33 and the suction connection portion 27. The wall portion 39 diverts the fluid flowing from the suction connection portion 27 to the suction chamber 29. If necessary, the wall portion 39 tapers the cross section in the reflux connection 37 or in the transition region between the pressure chamber 33 and the suction chamber 29, and as a result, from the reflux connection 37 to the suction chamber 29. The flowing fluid is accelerated.
[0014]
The fluid flowing out from the pressure chamber outlet 35, specifically the working fluid, entrains the working fluid in the region of the suction connection. That is, the fluid under pressure, which is returned directly from the consuming device to the pump, transfers its energy to the fluid entrained from the suction connection.
[0015]
Since the cross section of the suction chamber 29 immediately after the pressure chamber discharge port 35 is larger than the cross section of the discharge port itself, energy conversion is performed in the suction chamber, and the pressure in the suction chamber 29 is increased and increased by the energy conversion. As a result, the blade-type rotary pump 1 can suck the fluid with less cavitation.
[0016]
A modified embodiment of the vane-type rotary pump is shown in FIG. Here, the same parts are denoted by the same reference numerals. Therefore, the detailed description of the code is not performed as long as that.
[0017]
Also in the case of the embodiment shown here, the blade-type rotary pump 1 has a rotor 3 that is rotatably mounted inside the contour ring 9. The suction areas 17 and 19 of both pump parts are outlined by broken lines, and the pressurization areas 21 and 23 are similar. For the sake of clarity, the blades 7 are not shown here.
[0018]
In the case of the embodiment shown here, the reflux connection 37 opens into a pressure chamber 33 arranged at a distance from the contour ring 9, which pressure chamber 33 is connected to the pressure chamber outlet 35a. And 35b open to the suction connection 27. The cross sections of the pressure chamber discharge ports 35 a and 35 b are much smaller than the cross section of the reflux connection portion 37. Therefore, the fluid sent to the pressure chamber 33 through the reflux connection 37 flows out through the pressure chamber outlets 35a and 35b at a speed much higher than the speed given at the reflux connection 37.
[0019]
The fluid flowing into the suction connection 27 at a high speed entrains the fluid at the suction connection 27 and transfers energy to the fluid. The wall portion 39 provides the best mixing of both fluids so that the energy of the fluid supplied through the reflux connection 37 under overpressure is optimally transferred to the fluid at the suction connection 27. .
[0020]
The pressure chamber discharge ports 35a and 35b are arranged and formed as follows. That is arranged so as not to cause energy losses rebounding against the boundary wall 41 of the suction connection that fluid flowing out of the pressure chamber outlet 35a and 35b are positioned on opposite side of the pressure chamber outlet 35a and 35b, and is formed ing. The boundary wall 41 is part of the pipe connection leading to the tank, extending perpendicular to the plane of the drawing.
[0021]
The wall portion 39 also narrows the suction connection 27 in the transition region to the suction chamber 29. As a result, a so-called mixing chamber is formed here. By narrowing, the fluid flowing through is accelerated. Immediately behind the end of the wall portion 39, the cross section of the suction chamber 29 is enlarged. As a result, the pressure is now increased based on energy conversion. Based on this increased pressure, an overpressure fluid is brought into the suction areas 17 and 19.
[0022]
The embodiment shown in FIG. 2 of the blade-type rotary pump 1 is characterized by the following. That is, the wall portion 39 divides the inner chamber of the pump that houses the rotor 3 from the reflux connection portion 37 and from the suction connection portion 27. As a result, it is reliably prevented that the blade-type rotary pump 1 is emptied in a stopped state. Thus, the rotor is completely submerged in the fluid after the pump is stopped and therefore exhibits the best starting behavior. In other words, it is ensured that the vane-type rotary pump 1 does not run idle at the start and starts to convey the fluid without delay. However, the following is important. A communication portion (transition region) between the suction connection portion 27 and the suction chamber 29, and pressure discharge portions of the kidney-shaped pressurization regions 21 and 23 communicated with the working pressure side of the blade-type rotary pump 1, It arrange | positions so that it may be located upwards so that an oil collection chamber can be ensured. The oil in the oil collection chamber improves the starting characteristics of the pump.
[0023]
From the description of FIGS. 1 and 2, the following can be easily understood. That is, whether it is customary in the case of conventional pumps of the type mentioned here, or whether a flow control valve is used, for example in the case of a blade-type rotary pump for a steering assist system, the blade-type rotary pump 1 Does not have a flow control valve. Similarly, roller type rotary pumps and gear pumps not described in detail here do not have flow control valves as well. Such a flow control valve is expensive to assemble and causes high manufacturing costs. Moreover, pressurized in the suction chamber of the pump with the flow control valve is working flow control valve, only guaranteed when and returning to the suction region directly to the pump fluid from the pressure side of the pump.
[0024]
Thus, in comparison, the structure of the pump described on the basis of FIGS. 1 and 2 is much simpler. In addition, the pressurization of the suction area is always guaranteed when the fluid under pressure is returned from the consuming device.
[0025]
As described above, the pump described based on FIGS. 1 and 2 is characterized by a very simple structure. Cavitation in the suction area of the pump is prevented with high certainty by pressurizing the suction area with the fluid of the consuming device under pressure. As a result, noise generation and wear can be greatly reduced, and the pump speed limit can be increased.
[Brief description of the drawings]
FIG. 1 is a plan view of a first embodiment of a bladed rotary pump that has been cut open.
FIG. 2 is a plan view of a second embodiment of an incised blade-type rotary pump.
[Explanation of symbols]
1 Pump 27 Suction connection 29 Suction chamber 33 Pressure chamber 35; 35a; 35b Pressure chamber outlet 39 Wall portion

Claims (5)

A pump for supplying fluid to a consuming device, wherein the pump is configured to utilize a fluid under pressure returned from the consuming device for pressurization of the suction chamber (29).
A wall portion (39) for separating the suction chamber (29) of the pump (1) from the suction connection portion (27) is provided, and the wall portion (39) connects the suction connection portion (27) to the suction chamber (29). The first function of accelerating the fluid flowing through the suction connection portion (27) by narrowing in the transition region, and the transition region between the suction connection portion (27) and the suction chamber (29) secure an oil collecting chamber. Having a second function of securing the oil collecting chamber by separating the suction connecting portion (27) and the suction chamber (29) so as to be positioned as high as possible ;
And it communicates with the operating pressure side of the pump (1), a pressure discharge of the pressurized area (21, 23) also, that it is positioned above enough to ensure oil collecting chamber,
Features a pump.   The fluid returned from the consuming device is introduced into the pressure chamber (33), and the pressure chamber (33) is open to the suction chamber (29) in the pump (1). ) And the cross section of the pressure chamber outlet (35; 35a; 35b) is smaller than the cross section of the reflux connection (37) leading the fluid returned from the consuming device to the pressure chamber (33) The pump according to claim 1, characterized in that:   3. The suction chamber (29) according to claim 1 or 2, characterized in that the suction chamber (29) is fluidly coupled to the suction connection (27) and fluid is sucked from the tank via the suction connection (27). pump.   3. Pump according to claim 2, characterized in that the suction chamber (29) has a larger cross section than the pressure chamber outlet (35; 35a; 35b).   Pump according to claim 2 or 4, characterized in that the pressure chamber outlet (35a; 35b) opens directly into the suction connection (27).

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