Aviation plunger pump with floating return mechanism

Abstract

The invention discloses an aviation plunger pump with a floating return mechanism. A mounting seat is communicated with an inner cavity of a shell, a cylinder body is arranged in the mounting seat, and a main shaft is coaxially and fixedly connected in the cylinder body and fixedly connected with an external power device; the swash plate is rotationally arranged on the mounting base, stepped counter bores are formed in the end face of the swash plate, a through hole for the main shaft to penetrate through is coaxially formed in the center of a bottom counter table, and an annular platform between the two stages of counter bores is a step; the wear-resistant disc is arranged at the bottom of the sinking table; the plane end of a sliding shoe in a plunger assembly is located between a return plate and a wear-resistant plate, the inner concave end of the sliding shoe penetrates through an installation hole of the return plate and is hinged to a plunger head, and plungers are arranged in a cylinder body in parallel. The inner diameter of the pressure plate is smaller than the outer diameter of the return plate; the adjusting pad is fixedly connected between the pressure plate and the swash plate; the inner diameter of the adjusting pad is larger than the outer diameter of the return plate; an oil guide groove is circumferentially formed in the face, facing the return plate, of the pressing plate. Floating contact between the return plate and the pressing plate can be achieved, the floating gap can be adjusted, and lubrication can be facilitated.

Description

Technical Field

[0001] The invention relates to the field of aviation hydraulics, and in particular to an aviation plunger pump with a floating return mechanism. Background Art

[0002] As the power element of the aircraft hydraulic system, the aviation hydraulic pump is of great significance to the flight control and flight safety of the aircraft. The return mechanism is the variable control unit of the aviation hydraulic pump, which is mainly used to adjust the pump displacement to meet the needs of the hydraulic system of the aircraft under different working conditions. During use, the return mechanism of the existing plunger pump mostly adopts a ball joint internal support return plate limiter, or a screw sleeve to press the return plate limiter. However, if a ball joint support structure is adopted, the spherical surface grinding is difficult. Under the high-speed operation condition of the pump, there is severe friction between the return plate and the ball joint, which will cause the ball joint to burn for a long time and cause the pump function to fail. If a screw sleeve is used to press the return plate, due to the existence of the thread helix angle, it is easy to cause eccentric wear between the screw sleeve and the return plate. Long-term operation will cause the screw sleeve to loosen, and there is a risk of the return plate being broken. Summary of the invention

[0003] In view of the deficiencies of the prior art, the present invention provides an aviation plunger pump with a floating return mechanism.

[0004] The specific technical solutions are as follows:

[0005] An aviation plunger pump with a floating return mechanism comprises: a mounting seat, a housing, a cylinder, a main shaft, a swash plate, a swash plate bearing, a plunger assembly, and a wear plate, a return plate, an adjustment pad, and a pressure plate coaxially arranged from front to back; the rear end face of the mounting seat is relatively sealed with the front end face of the housing, and a communicating cavity is provided inside the mounting seat and the housing; the cylinder is installed in the cavity inside the housing, and the main shaft passes through a through hole coaxially provided in the center of the cylinder and is fixedly connected thereto; the main shaft is rotatably mounted on the mounting seat and the housing through a bearing, and is fixedly connected to an external power device;

[0006] The swash plate is a flat cylinder with two-stage stepped countersunk holes coaxially opened at the front end face, the first-stage countersunk hole starts from the front end face, the second-stage countersunk hole starts from the bottom face of the first-stage countersunk hole, and its diameter is smaller than the diameter of the first-stage countersunk hole, and a through hole is coaxially opened at the center of the second-stage countersunk hole for the main shaft to pass through; the sinking structure formed by the second-stage countersunk hole is recorded as a sinking platform, and the annular platform between the two-stage countersunk holes is recorded as a step; the radial ends of the swash plate are fixedly connected with shafts, which are respectively interference-mounted on the inner ring of the swash plate bearing, and the swash plate bearing is arranged on the mounting seat; the wear-resistant plate is coaxially mounted at the bottom of the sinking platform;

[0007] The plunger assembly comprises a plunger and a sliding shoe, one end of the sliding shoe is a plane, located between the return plate and the wear-resistant plate and connected to the two, and the other end is concave, passing through the mounting hole of the return plate, and is used to accommodate the plunger head and be hinged therewith; the plunger is arranged in parallel in the cavity inside the cylinder body;

[0008] The pressure plate is fixedly mounted on the step and is an annular structure, whose inner diameter is smaller than the outer diameter of the return plate, and is used to axially constrain the return plate; the adjustment pad is arranged between the pressure plate and the inclined plate, and is an annular structure, whose inner diameter is larger than the outer diameter of the return plate; a plurality of oil guide grooves are evenly arranged in the circumferential direction on the side of the pressure plate that contacts the return plate.

[0009] Furthermore, the wear-resistant disk is a disk structure with a through hole coaxially opened in the center, the size of the through hole is the same as the size of the through hole opened in the center of the inclined disk, and the wear-resistant disk is coaxially installed at the bottom of the sinker of the inclined disk through a positioning pin.

[0010] Furthermore, the return disk is a disk structure with a through hole coaxially opened in the center for the main shaft to pass through; a plurality of mounting holes are evenly opened in the circumferential direction on the outer periphery of the through hole of the return disk for mounting the plunger assembly.

[0011] Furthermore, the pressure plate and the adjustment pad are fixedly mounted on the step of the inclined plate through threaded connection.

[0012] Furthermore, it also includes a front bearing and a rear bearing; the front bearing, the main shaft, and the rear bearing are coaxially arranged in sequence, the front bearing is fixedly connected to the mounting seat, and the rear bearing is fixedly connected to the housing; one end of the main shaft is installed on the inner ring of the front bearing, and the other end is installed on the inner ring of the rear bearing.

[0013] Furthermore, the main shaft and the cylinder body are fixedly connected via a spline pair, wherein the main shaft is provided with an external spline, and the central through hole of the cylinder body is provided with an internal spline matching with the main shaft.

[0014] The beneficial effects of the present invention are:

[0015] (1) The present invention adopts a structure without ball joint support in which the return plate and the pressure plate are floatingly installed. The return plate and the pressure plate are in intermittent floating contact during movement. The floating gap can be adjusted by using adjustment gaskets of different thicknesses to reduce the impact between the pressure plate and the return plate during pump operation.

[0016] (2) The present invention provides an oil guide groove on the pressure plate to facilitate lubrication between the pressure plate and the return plate, thereby reducing friction during the movement of the return plate and improving the working efficiency of the pump. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a cross-sectional view of an aviation plunger pump with a floating return mechanism in an embodiment of the present invention.

[0018] Figure 2 Schematic diagram of the structure of the swash plate in the embodiment of the present invention.

[0019] Figure 3 It is a partial cross-sectional view of the return mechanism assembly in the embodiment of the present invention.

[0020] Figure 4 Schematic diagram of the structure of the wear-resistant disc in the embodiment of the present invention.

[0021] Figure 5 It is a schematic diagram of the structure of the return disk in an embodiment of the present invention.

[0022] Figure 6 Schematic diagram of the structure of the adjustment pad in the embodiment of the present invention.

[0023] Figure 7 Schematic diagram of the structure of the pressure plate in the embodiment of the present invention.

[0024] In the figure, there are mounting seat 1, front bearing 2, main shaft 3, swash plate 4, wear-resistant plate 5, plunger assembly 6, housing 7, rear bearing 8, cylinder block 9, swash plate bearing 10, pressure plate 11, adjustment pad 12, and return plate 13. DETAILED DESCRIPTION

[0025] The present invention will be described in detail below according to the accompanying drawings and preferred embodiments, and the purpose and effect of the present invention will become more clear. The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0026] like Figure 1 As shown, an aviation plunger pump with a floating return mechanism includes: a mounting seat 1, a front bearing 2, a main shaft 3, a swash plate 4, a wear-resistant plate 5, a plunger assembly 6, a housing 7, a rear bearing 8, a cylinder body 9, a swash plate bearing 10, a pressure plate 11, an adjustment pad 12, and a return plate 13.

[0027] The rear end face of the mounting seat 1 is installed opposite to the front end face of the housing 7, and a sealing groove is provided at the periphery of the end faces where the two meet, in which a sealing ring is arranged to achieve sealing between the mounting seat 1 and the housing 7. A communicating cavity is provided inside the mounting seat 1 and the housing 7, and the cylinder body 9 is installed in the cavity inside the housing 7. A through hole is coaxially provided inside the cylinder body 9, and the main shaft 3 is coaxially arranged in the through hole; an external spline is provided on the main shaft 3, and an internal spline matching the main shaft 3 is provided in the through hole at the center of the cylinder body 9. The connection between the cylinder body 9 and the main shaft 3 is achieved through the spline pair, ensuring that the cylinder body 9 rotates synchronously with the main shaft 3. The front bearing 2, the main shaft 3, and the rear bearing 8 are coaxially arranged in sequence, wherein the front bearing 2 is fixedly connected to the mounting seat 1, and the rear bearing 8 is fixedly connected to the housing 7; one end of the main shaft 3 is installed on the inner ring of the front bearing 2, and the other end is installed on the inner ring of the rear bearing 8, so that the main shaft 3 can achieve free rotation around the axis and ensure the stability and precision of the rotation of the main shaft 3. According to the working conditions, the assembly relationship between the main shaft 3 and the front bearing 2 and the rear bearing 8 is determined. Under light load conditions, a transition fit or a clearance fit is adopted between the main shaft 3 and the front bearing 2 and the rear bearing 8; under heavy load conditions, a transition fit or an interference fit is adopted between the main shaft 3 and the front bearing 2 and the rear bearing 8.

[0028] like Figure 2 As shown, the swash plate 4 is a flat cylinder with two-stage stepped countersunk holes coaxially opened on one end surface, and the stepped countersunk holes are used to install the return mechanism; Figure 3 As shown, the return mechanism includes: a plunger assembly 6, and a wear-resistant plate 5, a return plate 13, an adjustment pad 12, and a pressure plate 11 arranged coaxially in sequence. The first-stage countersunk hole starts from the end face, and the second-stage countersunk hole starts from the bottom surface of the first-stage countersunk hole, and its diameter is smaller than the diameter of the first-stage countersunk hole. A through hole is coaxially opened in the center of the second-stage countersunk hole for the main shaft 3 to pass through; the sinking structure formed by the second-stage countersunk hole is recorded as a sinking platform, and the annular platform formed between the two-stage countersunk holes due to the different diameters is recorded as a step. A number of threaded holes are opened on the step for installing the adjustment pad 12 and the pressure plate 11. A through hole is also coaxially opened at the center of the swash plate 4, and the main shaft 3 can pass through the through hole, and after installation, the swash plate 4 has a certain inclination angle relative to the main shaft 3. Both radial ends of the swash plate 4 are fixedly connected with shafts. The shafts at both ends of the swash plate 4 are installed on the inner ring of the swash plate bearing 10 and are interference fit therewith. The outer ring of the swash plate bearing 10 is installed on the bearing seat. Different from the existing swash plate installation method, the bearing seat and the mounting seat 1 of the present invention are an integrated structure. There is no need to install the bearing seat on the mounting seat 1 by mechanical connection, which reduces the assembly error of parts.

[0029] like Figure 4 As shown, the wear-resistant disk 5 is a disk structure with a through hole coaxially opened in the center. The size of the through hole is larger than the diameter of the main shaft. The wear-resistant disk 5 is coaxially installed at the bottom of the sinker of the inclined disk 4 through a positioning pin to provide a stable sliding surface for the plunger assembly 6.

[0030] like Figure 5As shown, the return plate 13 is a disc structure with a through hole coaxially opened in the center, and the size of the through hole is the same as the through hole opened in the wear-resistant plate 5. A plurality of mounting holes are evenly opened in the circumferential direction on the outer periphery of the through hole of the return plate for mounting the plunger assembly 6.

[0031] There are multiple plunger assemblies 6, and their number is consistent with the number of mounting holes opened on the return plate 13. Each plunger assembly 6 consists of a plunger and a sliding shoe. One end of the sliding shoe is flat and the other end is concave, which is used to accommodate the plunger. The plunger and the sliding shoe are hinged, and the plunger can rotate flexibly therein. The plunger is arranged in parallel in the cavity inside the cylinder body (that is, its axis is parallel to the axis of the cylinder body). The concave end of the sliding shoe passes through the mounting hole of the return plate 13, and the flat end is located between the return plate 13 and the wear-resistant plate 5 and connected to both.

[0032] The pressure plate 11 is fixed to the step of the swash plate 4 by screws, and an adjustment pad 12 is installed between the pressure plate 11 and the swash plate 4, which is also fixed by screws. Figure 6 As shown, the adjustment pad 12 is an annular structure with through holes distributed along the annulus, and the number, size and position of the through holes correspond one by one to the threaded holes opened on the swash plate 4; the inner circle diameter of the adjustment pad 12 is slightly larger than the outer circle diameter of the return plate 13, so as to prevent the return plate 13 and the adjustment pad 12 from rubbing and interfering with each other during movement, and also to avoid wear of the adjustment pad 12.

[0033] like Figure 7 As shown, the pressure plate 11 is an annular structure, and through holes are also distributed along the annulus, and the number, size and position of the through holes correspond to the through holes on the adjustment pad 12 one by one; the inner diameter of the pressure plate 11 is smaller than the outer diameter of the return plate 13, which plays a role of axial constraint on the return plate 13. This embodiment also has a lubrication design: the side of the pressure plate 11 in contact with the return plate 13 is evenly provided with a number of oil guide grooves along the circumferential direction to store oil. When the pump is working normally, the oil enters the gap between the return plate 13 and the pressure plate 11 through the oil guide grooves to form an oil film, which plays a lubricating role and reduces wear. Evenly distributed oil guide grooves can achieve uniform lubrication, improve the load-bearing capacity of the oil film, and facilitate heat dissipation; if unevenly distributed, it will cause problems such as eccentric loading, eccentric wear and abnormal wear.

[0034] When the hydraulic pump is working, since the adjustment pad 12 is installed between the pressure plate 11 and the swash plate 4, there is a small axial clearance between the return plate 13 and the pressure plate 11. When the pump sucks oil, the main shaft 3 drives the cylinder body 9 to rotate, and the plunger assembly 6 extends outward under the pulling force of the return plate 13. At this time, the return plate 13 and the pressure plate 11 are theoretically in contact on the pump suction side. At the same time, since the pressure plate 11 is provided with an oil guide groove, a discontinuous oil film can be formed between the rotating return plate 13 and the pressure plate 11. Due to the existence of the oil film, the return plate 13 and the pressure plate 11 are not in direct contact. The two are in contact where the oil film is discontinuous, and the two interact through the oil film where the oil film is continuous. Therefore, the return plate 13 and the pressure plate 11 present a floating state of intermittent contact, that is, the return plate 13 and the pressure plate 11 are in floating contact during the movement. During assembly, adjusting pads 12 of different thicknesses are selected according to actual measurement conditions to control the axial clearance between the pressure plate 11 and the return plate 13 .

[0035] The present invention adopts the method of floating limit return plate 13 of pressure plate 11 to constrain return plate 13. At the same time, an adjustment pad 12 is installed between pressure plate 11 and inclined plate 4. The thickness of adjustment pad 12 is selected according to the actual processing size of parts. At the same time, a plurality of oil guide grooves are opened along the circumferential direction on the contact surface of pressure plate 11 and return plate 13 to store oil. The return plate 13 is in floating contact with pressure plate 11. When the pump is working normally, an oil film can be formed between the two.

[0036] The main shaft 3 is connected to the aircraft engine through a coupling sleeve. The main shaft 3 drives the cylinder body 9, the plunger assembly 6, and the return plate 13 to rotate together. Since the swash plate 4 has an inclination angle relative to the main shaft 3, the plunger of the plunger assembly 6 reciprocates along the axial direction under the constraint of the return plate 13 when the cylinder body 9 rotates. When the plunger extends along the cylinder body 9, the pressure plate 11 contacts the return plate 13, driving the plunger to absorb oil; when the plunger retracts, the oil is discharged. Multiple plungers operate periodically, and the pump continuously absorbs and discharges oil.

[0037] Those skilled in the art can understand that the above are only preferred examples of the invention and are not intended to limit the invention. Although the invention is described in detail with reference to the above examples, those skilled in the art can still modify the technical solutions recorded in the above examples or replace some of the technical features therein with equivalents. Any modification, equivalent replacement, etc. made within the spirit and principle of the invention shall be included in the protection scope of the invention.

Claims

1. An aviation plunger pump with a floating return mechanism, characterized in that: include: The mounting seat, the housing, the cylinder body, the main shaft, the swash plate, the swash plate bearing, the plunger assembly, and the wear-resistant plate, the return plate, the adjustment pad, and the pressure plate are coaxially arranged from front to back; the rear end face of the mounting seat is relatively sealed with the front end face of the housing, and a communicating cavity is provided inside the mounting seat and the housing; the cylinder body is installed in the cavity inside the housing, and the main shaft passes through the through hole coaxially provided in the center of the cylinder body and is fixedly connected thereto; the main shaft is rotatably mounted on the mounting seat and the housing through the bearing, and is fixedly connected to the external power device; The swash plate is a flat cylinder with two-stage stepped countersunk holes coaxially opened at the front end face, the first-stage countersunk hole starts from the front end face, the second-stage countersunk hole starts from the bottom face of the first-stage countersunk hole, and its diameter is smaller than the diameter of the first-stage countersunk hole, and a through hole is coaxially opened at the center of the second-stage countersunk hole for the main shaft to pass through; the sinking structure formed by the second-stage countersunk hole is recorded as a sinking platform, and the annular platform between the two-stage countersunk holes is recorded as a step; the radial ends of the swash plate are fixedly connected with shafts, which are respectively interference-mounted on the inner ring of the swash plate bearing, and the swash plate bearing is arranged on the mounting seat; the wear-resistant plate is coaxially mounted at the bottom of the sinking platform; The plunger assembly comprises a plunger and a sliding shoe, one end of the sliding shoe is a plane, located between the return plate and the wear-resistant plate and connected to the two, and the other end is concave, passing through the mounting hole of the return plate, and is used to accommodate the plunger head and be hinged therewith; the plunger is arranged in parallel in the cavity inside the cylinder body; The pressure plate is fixedly mounted on the step and is an annular structure, whose inner diameter is smaller than the outer diameter of the return plate, and is used to axially constrain the return plate; the adjustment pad is arranged between the pressure plate and the inclined plate, and is an annular structure, whose inner diameter is larger than the outer diameter of the return plate; a plurality of oil guide grooves are evenly arranged in the circumference of the side of the pressure plate that contacts the return plate.

2. The aviation plunger pump with a floating return mechanism according to claim 1, characterized in that: The wear-resistant disc is a disc structure with a through hole coaxially opened in the center. The size of the through hole is the same as the size of the through hole opened in the center of the inclined plate. The wear-resistant disc is coaxially installed on the bottom of the sinker of the inclined plate through a positioning pin.

3. The aviation plunger pump with a floating return mechanism according to claim 1, characterized in that: The return disk is a disk structure with a through hole coaxially opened in the center for the main shaft to pass through; a plurality of mounting holes are evenly opened in the circumferential direction on the outer periphery of the through hole of the return disk for mounting the plunger assembly.

4. The aviation plunger pump with a floating return mechanism according to claim 1, characterized in that: The pressure plate and the adjusting pad are fixedly mounted on the step of the inclined plate through threaded connection.

5. The aviation plunger pump with a floating return mechanism according to claim 1, characterized in that: It also includes a front bearing and a rear bearing; the front bearing, the main shaft and the rear bearing are coaxially arranged in sequence, the front bearing is fixedly connected to the mounting seat, and the rear bearing is fixedly connected to the housing; one end of the main shaft is mounted on the inner ring of the front bearing, and the other end is mounted on the inner ring of the rear bearing.

6. The aviation plunger pump with a floating return mechanism according to claim 1, characterized in that: The main shaft and the cylinder body are fixedly connected through a spline pair, wherein the main shaft is provided with an external spline, and the central through hole of the cylinder body is provided with an internal spline matched with the main shaft.

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