CN105257495A - Flow dispersion switch control digital axial plunger pump and control method thereof - Google Patents

Abstract

The invention discloses a flow discrete switch controlled digital axial piston pump and a control method thereof. The plunger pump casing, the rear end cover and the rear end cover are sealed in sequence; the swash plate is installed inside the plunger pump casing through the first bearing; the main shaft passes through the plunger pump casing, the swash plate, and the plunger cavity in sequence and the second bearing; the main shaft is connected with the swash plate through a key; the plunger is installed in the spherical sleeve of the sliding shoe; the sliding shoe is tightly pressed on the swash plate, and the rotation of the main shaft drives the swash plate to rotate, and then drives the plunger in the plunger cavity The reciprocating movement is realized in the center; the inlet switch valve with the same number as the number of plungers is inserted on the oil road connected to the inlet oil passage in the axial direction of the rear end cover; the oil passage connected to the outlet oil passage in the radial direction of the rear end cover is inserted with The same number of outlet switching valves as the number of plungers; by adjusting the working sequence of the inlet switching valve and outlet switching valve corresponding to each plunger, the variable control of the output flow of the digital axial piston pump with discrete flow switch control can be realized.

Description

Flow Discrete Switch Control Digital Axial Piston Pump and Its Control Method

technical field

The invention relates to digital hydraulic component technology, in particular to designing a digital axial piston pump controlled by a flow discrete switch and a control method thereof.

Background technique

Digital hydraulic technology is a new type of hydraulic control technology, which is characterized by controlling and adjusting the output flow of components by using on-off valves. The switch valve has only two output variables, namely fully open "1" and fully closed "0". Through the adjustment of the switch valve, the discrete control of the output flow of the component can be realized. When the response frequency of the switch valve increases, the average value of the discretized output flow can be used to approximately replace the traditional continuous flow output. Since the digital hydraulic based on switch control has the advantages of strong anti-pollution ability of switch control, low processing cost and simple structure, as well as the advantages of high flexibility of digital control, strong operability and high degree of integration, it is the future development of hydraulic technology. an important direction.

At the same time, for hydraulic pump components, there is a serious wear problem in the flow distribution pair of the traditional variable plunger hydraulic pump. Pumps are more expensive. By introducing the switch valve digital control technology into the field of axial piston pump, its structure can be simplified, and at the same time, the variable control of the pump output can be realized through the combined adjustment of the switch valve, which greatly increases the operability of the axial variable pump. .

Contents of the invention

The purpose of the present invention is to design a flow discrete switch control digital axial piston pump, through the control of the inlet switch valve and the outlet switch valve, the variable characteristics of the axial piston pump can be realized.

In order to achieve the above object, the technical scheme adopted in the present invention is as follows:

A digital axial piston pump controlled by a flow discrete switch includes a plunger pump housing, a plunger, a plunger cavity, a swash plate, a main shaft, an inlet on-off valve, an outlet on-off valve, a rear end cover, a shoe, a key, The first bearing, the second bearing, the rear end cover;

The plunger pump casing, the rear end cover and the rear end cover are sealed in sequence; the swash plate is installed inside the plunger pump casing through the first bearing; the main shaft passes through the plunger pump casing, the swash plate, and the plunger cavity in turn and the second bearing; the main shaft is connected with the swash plate through a key; the plunger is installed in the spherical sleeve of the sliding shoe; the sliding shoe is tightly pressed on the swash plate, and the rotation of the main shaft drives the swash plate to rotate, and then drives the plunger in the plunger cavity The reciprocating movement is realized in the center; the inlet switch valve with the same number as the number of plungers is inserted on the oil road connected to the inlet oil passage in the axial direction of the rear end cover; the oil passage connected to the outlet oil passage in the radial direction of the rear end cover is inserted with The same number of outlet switch valves as the number of plungers.

The inlet on-off valve and the outlet on-off valve realize the control of the input flow and output flow of each plunger through pulse control. The key is a flat key, a semicircular key, a wedge key, a tangential key or a spline. The number of plungers installed in the plunger pump can be even or odd.

Preferably, the digital axial piston pump controlled by flow discrete switches further includes an oil inlet and an oil outlet, and the oil inlet and oil outlet are arranged on the rear end cover.

The flow control method of the plunger pump is divided into three modes, namely full flow output, combined working condition output and zero flow output;

When outputting at full flow, open all inlet on-off valves when the plunger absorbs oil, and open all outlet on-off valves when the plunger discharges oil;

When outputting in combined working conditions, determine the number n of plungers used for oil discharge. The number of plungers that do not need to output oil flow in the plunger pump is m-n, and m is the total number of plungers. When the plunger pump sucks oil, open all Inlet on-off valve, when the plunger pump discharges oil, open the outlet on-off valves corresponding to the n plunger cavities used for flow output to discharge oil from the pump, and the remaining m-n plungers open their corresponding inlet on-off valves to make the cavities The internal oil flows back into the oil inlet of the pump to realize the idle speed function, so as to adjust the output flow of the plunger pump;

At zero flow output, all the inlet on-off valves are opened when the plunger sucks oil, and all inlet on-off valves are opened when the plunger discharges oil. At this time, the plunger pump has no flow output.

The beneficial effects that the present invention has are:

1. Adjust the output variable of the pump by adjusting the switching sequence of the inlet on-off valve and the outlet on-off valve;

2. The flow discrete switch control digital axial piston pump has the advantages of digital control technology, flexible control, strong anti-interference ability and good control characteristics;

3. Discrete flow switch control The digital axial piston pump applies switch control technology, which has the advantages of simple structure, fast action, strong anti-pollution ability, high reliability and low processing cost.

4. The traditional valve control method is replaced by the switch control method, which effectively improves the service life of the plunger pump.

Description of drawings

Figure 1 is a schematic diagram of the structure of a digital axial piston pump controlled by a flow discrete switch;

Figure 2 is a cross-sectional view of the pump body structure of a digital axial piston pump controlled by a flow discrete switch;

Fig. 3 is a schematic diagram of the structure of the rear end cover of the digital axial piston pump controlled by the flow discrete switch;

Fig. 4 is a schematic diagram of a control method of a digital axial piston pump controlled by a flow discrete switch.

In the figure: 1. Piston pump housing, 2. Plunger, 3. Plunger cavity, 4. Swash plate, 5. Main shaft, 6. Inlet on-off valve, 7. Outlet on-off valve, 8. Rear end cover, 9, sliding shoe, 10, key, 11, first bearing, 12, second bearing, 13, rear end cover plate, 14, oil inlet, 15, oil outlet.

detailed description

The present invention will be further described below in conjunction with the accompanying drawings and specific examples, and this embodiment should not be regarded as a limitation of the present invention.

As shown in Figure 1 and Figure 2, a digital axial piston pump controlled by a flow discrete switch includes a plunger pump housing 1, a plunger 2, a plunger cavity 3, a swash plate 4, a main shaft 5, and an inlet switch valve 6. Outlet switching valve 7, rear end cover 8, sliding shoe 9, key 10, first bearing 11, second bearing 12, rear end cover 13;

The plunger pump casing 1, the rear end cover 8 and the rear end cover plate 13 are sequentially sealed and connected; the swash plate 4 is installed inside the plunger pump casing 1 through the first bearing 11; the main shaft 5 passes through the plunger pump casing 1 in sequence , swash plate 4, plunger cavity 3 and second bearing 12; the main shaft 5 is connected with the swash plate 4 through the key 10; the plunger 2 is installed in the spherical sleeve of the sliding shoe 9; the sliding shoe 9 is tightly pressed on the swash plate 4 , through the rotation of the main shaft 5, the swash plate 4 is driven to rotate, and then the plunger 2 is driven to reciprocate in the plunger cavity 3; number of inlet on-off valves 6; the outlet cover valve 7 with the same number as the number of plungers is inserted on the oil road connected to the outlet oil passage in the radial direction of the rear end cover 8.

The inlet on-off valve 6 and the outlet on-off valve 7 realize the control of the input flow and output flow of each plunger through pulse control. The key 10 is a flat key, a semicircular key, a wedge key, a tangential key or a spline. The number of plungers installed in the plunger pump can be even or odd.

As shown in Fig. 3, preferably, the described a kind of flow discrete switch control digital axial piston pump also includes oil inlet 14 and oil outlet 15, and described oil inlet 14 and oil outlet 15 are set On the rear end cover 8.

As shown in Figure 4, by adjusting the working sequence of the inlet switch valve and outlet switch valve corresponding to each plunger, the variable control of the output flow of the digital axial piston pump controlled by the flow discrete switch can be realized. The flow rate of the plunger pump The control method is divided into three ways, namely full flow output, combined working condition output and zero flow output;

At full flow output, open all inlet on-off valves 6 when plunger 2 absorbs oil, and open all outlet on-off valves 7 when plunger 2 discharges oil;

When outputting in combined working conditions, determine the number n of plungers used for oil discharge. The number of plungers that do not need to output oil flow in the plunger pump is m-n, where m is the total number of plungers. When the plunger pump sucks oil, open all Inlet on-off valve 6, when the plunger pump discharges oil, open the outlet on-off valve 7 corresponding to n plunger cavities for flow output to make the pump discharge oil, and the remaining m-n plungers open their corresponding inlet on-off valve 6, Make the oil in the chamber flow back into the oil inlet of the pump to realize the idle speed function, so as to adjust the output flow of the plunger pump;

At zero flow output, all inlet on-off valves 6 are opened when plunger 2 absorbs oil, and all inlet on-off valves 6 are opened when plunger 2 discharges oil. At this time, the plunger pump has no flow output.

Claims (6)

1. a flow discrete switch control figure formula axial piston pump, it is characterized in that: comprise plunger pump shell (1), plunger (2), plunger cavity (3), swash plate (4), main shaft (5), inlet switch valve (6), gate out switch valve (7), rear end cover (8), piston shoes (9), key (10), clutch shaft bearing (11), the second bearing (12), rear-end plate (13);

Plunger pump shell (1), rear end cover (8) and rear-end plate (13) are tightly connected successively; It is inner that swash plate (4) is arranged on plunger pump shell (1) by clutch shaft bearing (11); Main shaft (5) is successively through plunger pump shell (1), swash plate (4), plunger cavity (3) and the second bearing (12); Main shaft (5) is connected with swash plate (4) by key (10); Plunger (2) is arranged in piston shoes (9) sphere cover; Piston shoes (9) are pressed on swash plate (4), rotarily drive swash plate (4) and rotate, then drive plunger (2) to realize to-and-fro motion in plunger cavity (3) by main shaft (5); Rear end cover (8) axial direction and the inlet switch valve (6) oil circuit that import oil duct is connected being fitted with the identical number with plunger number; The oil circuit that rear end cover (8) radial direction is connected with outlet oil duct is fitted with the gate out switch valve (7) of the identical number with plunger number.

2. a kind of flow discrete switch control figure formula axial piston pump according to claim 1, is characterized in that: described inlet switch valve (6), gate out switch valve (7) realize the control to each plunger input flow rate and output flow by Pulse Width Control.

3. a kind of flow discrete switch control figure formula axial piston pump according to claim 1, is characterized in that: described key (10) is flat key, woodruff key, wedge key, tangent key or spline.

4. a kind of flow discrete switch control figure formula axial piston pump according to claim 1, is characterized in that: the plunger number installed in described plunger pump can be even number also can be odd number.

5. a kind of flow discrete switch control figure formula axial piston pump according to claim 1, characterized by further comprising filler opening (14) and oil outlet (15), described filler opening (14) and oil outlet (15) are arranged on rear end cover (8).

6. a flow control method for plunger pump as claimed in claim 1, is characterized in that: described flow control method is divided into three kinds of modes, and namely full flow exports, composite condition exports and zero delivery exports;

When full flow exports, open whole inlet switch valve (6) during plunger (2) oil suction, during plunger (2) oil extraction, open whole gate out switch valve (7);

When composite condition exports, determine the plunger number n of oil extraction, plunger pump does not need the plunger number carrying out the output of fluid flow to be m-n, m is plunger sum, when plunger pump oil suction, open whole inlet switch valve (6), during plunger pump oil extraction, the gate out switch valve (7) opened for n plunger cavity volume of flow output is corresponding makes pump oil extraction, remain the inlet switch valve (6) that m-n plunger then opens its correspondence, make its chamber inner fluid pass back into pump filler opening, realize idling function, with the output flow of this pilot plunger pump;

When zero delivery exports, open whole inlet switch valve (6) during plunger (2) oil suction, open whole inlet switch valve (6) during plunger (2) oil extraction, now plunger pump does not have flow to export.