Gear pump with anti-stiction oil lubrication

Abstract

The utility model discloses a gear pump with anti -stuck oil lubrication function is equipped with the unloading groove on the side plate of rear cover side, and the unloading groove two ends communicate with the axle hole, and the wear -resistant cover inner wall on the rear cover is equipped with the oil guide groove, and the oil guide groove far away one end of side plate communicates with the oil absorption cavity, the utility model discloses the unloading groove of being equipped with on the rear cover side side plate and the oil guide groove of being equipped with on the wear -resistant cover inner wall of opposite, two structures cooperate, solve the problem that the oil liquid of present gear pump stuck oil area can not discharge in time, and the unloading groove guides stuck oil and flows into the axle hole, and the oil guide groove forms low pressure area in the axle hole because communicating with the oil absorption cavity, and through the negative pressure effect accelerates stuck oil and discharges, and the stuck oil residue is reduced greatly, avoids oil liquid heating, pump body vibration and noise, and makes oil liquid direct action on the friction contact surface of driving shaft, driven shaft and wear -resistant cover simultaneously, realizes the shaft system sustained lubrication, reduces processing and maintenance cost, improves equipment service life.

Description

Technical Field

[0001] This utility model relates to a gear pump, specifically a gear pump with anti-trapped oil lubrication function. Background Technology

[0002] Gear pumps are common power components in hydraulic systems, with their core consisting of a pump body structure and an internal gear set. During operation, an external power source drives the drive gear to rotate, which in turn drives the driven gear to rotate synchronously in the opposite direction. The meshing line of the two gears divides the pump body into an oil suction chamber and an oil discharge chamber. The volume between the teeth in the suction chamber expands to draw in oil, while the volume between the teeth in the discharge chamber decreases to compress and output oil, thus converting mechanical energy into hydraulic pressure energy. Due to their compact structure and high reliability, gear pumps are widely used in engineering machinery, machine tools, and other fields.

[0003] Existing gear pumps have significant shortcomings in use. When the gears mesh, the front teeth do not disengage while the rear teeth have already engaged, forming a closed oil trapping zone. The oil cannot be discharged from the trapped zone in time, which can easily cause oil overheating, pump vibration, and noise. Utility Model Content

[0004] The purpose of this invention is to provide a gear pump with anti-trapped oil lubrication function to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, this utility model provides the following technical solution: A gear pump with anti-trapped oil lubrication function includes a pump body structure and a gear set. The two ends of the two gear shafts in the gear set are installed in the mounting holes of the pump body structure through wear-resistant sleeves. Side plates are provided between the end faces of the two gears of the gear set and the inner wall of the pump body structure. The two gear shafts of the gear set pass through the shaft holes of the side plates. An unloading groove is opened on the side plate on one side of the rear cover, which is opposite to the trapped oil area. The two ends of the unloading groove are connected to the shaft holes. An oil guide groove is opened on the inner wall of the wear-resistant sleeve inside the rear cover. The end of the oil guide groove away from the side plate is connected to the oil suction chamber.

[0006] As a further embodiment of this utility model: the unloading groove is an arc-shaped groove, the oil guide groove is a U-shaped structure, the oil guide groove extends along the axial direction of the wear-resistant sleeve, and passes through from one end of the wear-resistant sleeve near the side plate to one end near the inner wall of the rear cover, with the groove opening of the oil guide groove facing the inner hole of the wear-resistant sleeve.

[0007] As a further embodiment of this utility model: the pump body structure consists of a pump body and a front cover and a rear cover disposed on both sides of the pump body, and the pump body, the front cover and the rear cover are fastened together by connecting bolts.

[0008] As a further embodiment of this utility model: the gear set includes a drive shaft and a driven shaft, and a drive gear and a driven gear respectively mounted on the drive shaft and the driven shaft, wherein the drive gear and the driven gear are meshed together.

[0009] As a further embodiment of this utility model: the two ends of the drive shaft and the driven shaft are installed in the front cover and the rear cover through wear-resistant sleeves. The wear-resistant sleeves are fixedly connected in the mounting holes of the front cover and the rear cover. The drive shaft and the driven shaft are rotatably connected to the inner wall of the wear-resistant sleeves. One end of the drive shaft passes through the front cover and is connected to an external power source. A seal is provided at the point where the drive shaft passes through the front cover.

[0010] As a further improvement of this utility model: the side plate is positioned by the steps on the inner wall of the pump body and is pressed and fixed by the front cover and the rear cover, and the end face of the side plate near the gear is in contact with the end faces of the driving gear and the driven gear.

[0011] As a further improvement of this utility model: the side plate has an 8-shaped structure, and two shaft holes are symmetrically opened along the center line of the width direction of the side plate. The shaft holes correspond to the driving shaft and the driven shaft. The driving shaft and the driven shaft are respectively located in the two shaft holes and are rotatably connected to the inner wall of the shaft holes.

[0012] As a further improvement of this utility model, both the driving gear and the driven gear adopt a helical gear structure.

[0013] Compared with the prior art, the beneficial effects of this utility model are as follows: A gear pump with anti-trapped oil lubrication function solves the problem of oil not being discharged in time in the oil trapping zone of existing gear pumps by using an unloading groove opened on the side plate of the rear cover and an oil guide groove opened on the inner wall of the wear-resistant sleeve. The two structures work together to solve the problem of oil not being discharged in time in the oil trapping zone of existing gear pumps. The unloading groove guides the trapped oil into the shaft hole, and the oil guide groove forms a low-pressure zone in the shaft hole because it is connected to the oil suction chamber. The negative pressure effect accelerates the discharge of trapped oil, greatly reduces trapped oil residue, and avoids oil heating, pump body vibration and noise. At the same time, the trapped oil transported by the unloading groove provides a stable oil source for the oil guide groove, so that the oil directly acts on the friction contact surface of the drive shaft, driven shaft and wear-resistant sleeve, realizes continuous lubrication of the shaft system, reduces processing and maintenance costs, and improves the service life of the equipment. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a gear pump with anti-trapped oil lubrication function.

[0015] Figure 2 This is a schematic diagram of the internal structure of a gear pump with anti-trapped oil lubrication function.

[0016] Figure 3 This is a schematic diagram of the unloading groove and oil guide groove in a gear pump with anti-trapped oil lubrication function.

[0017] Figure 4 This is an enlarged view of point A in a gear pump with anti-trapped oil lubrication function.

[0018] Figure 5 This is a partial cross-sectional view of a gear pump with anti-trapped oil lubrication function.

[0019] Figure 6 This is an enlarged view of point B in a gear pump with anti-trapped oil lubrication function.

[0020] Figure 7 This is a schematic diagram of the side plate in a gear pump with anti-trapped oil lubrication function.

[0021] In the diagram: pump body 1, front cover 2, rear cover 3, drive shaft 4, driven shaft 5, drive gear 6, driven gear 7, wear-resistant sleeve 8, side plate 9, shaft hole 91, seal 10, unloading groove 11, oil guide groove 12, oil suction chamber 20, oil discharge chamber 30. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] Please see Figure 1 and Figure 2 In this embodiment of the utility model, a gear pump with anti-trapped oil lubrication function includes a pump body structure and a gear set installed inside it. The gear set drive shaft is connected to an external power source and drives it to rotate. The meshing line of the two gears of the gear set divides the inner cavity of the pump body structure into an oil suction chamber 20 and an oil discharge chamber 30 (not shown in the figure), realizing the conversion of mechanical energy into oil pressure energy.

[0024] The pump body structure consists of a pump body 1 and a front cover 2 and a rear cover 3 located on both sides of the pump body. The pump body 1, the front cover 2 and the rear cover 3 are fastened together by connecting bolts.

[0025] The gear set includes a drive shaft 4 and a driven shaft 5 (not shown in the diagram), and a drive gear 6 and a driven gear 7 respectively mounted on the drive shaft 4 and the driven shaft 5. The drive gear 6 and the driven gear 7 are meshed together. Figure 3 As shown, the two ends of the drive shaft 4 and the driven shaft 5 are installed in the front cover 2 and the rear cover 3 through the wear-resistant sleeve 8. The wear-resistant sleeve 8 is fixedly connected in the mounting holes of the front cover 2 and the rear cover 3. The drive shaft 4 and the driven shaft 5 are rotatably connected to the inner wall of the wear-resistant sleeve 8. One end of the drive shaft 4 passes through the front cover 2 and is connected to an external power source. A seal 10 is provided at the point where the drive shaft 4 passes through the front cover 2 to prevent high-pressure oil from leaking out of the body.

[0026] like Figure 4 and Figure 7As shown, the two end faces of the driving gear 6 and the driven gear 7 are respectively provided with side plates 9 between the front cover 2 and the rear cover 3. The side plates 9 are positioned by the steps on the inner wall of the pump body 1 and are pressed and fixed by the front cover 2 and the rear cover 3. The end face of the side plate 9 near the gear is in contact with the end face of the driving gear 6 and the driven gear 7.

[0027] The side plate 9 has an 8-shaped structure, with two shaft holes 91 symmetrically opened along the centerline of the width direction of the side plate 9. The shaft holes 91 correspond to the driving shaft 4 and the driven shaft 5. The driving shaft 4 and the driven shaft 5 are respectively located in the two shaft holes 91 and are rotatably connected to the inner wall of the shaft holes 91.

[0028] Both the driving gear 6 and the driven gear 7 adopt a helical gear structure. Compared with spur gears, the meshing process of helical gears is smoother, which can effectively eliminate meshing impact and reduce the operating noise of the gear pump from about 80 decibels of spur gears to about 70 decibels.

[0029] When the gears of the gear pump mesh, the first pair of meshing teeth has not completely disengaged while the second pair has already engaged. These two sets of meshing teeth, together with the pump body, form a closed, small space, namely the oil trapping zone. The inability to drain oil from this zone in a timely manner can cause damage such as oil overheating, noise, and vibration. To solve this problem, this invention provides an unloading groove 11 on the side plate 9 of the rear cover 3, opposite to the oil trapping zone. The two ends of the unloading groove 11 are connected to the shaft hole 91, allowing the oil in the oil trapping zone to flow into the shaft hole through the unloading groove 11. The unloading groove 11 can be an arc-shaped groove or a straight groove. In this embodiment, an arc-shaped groove is preferred. The curve of the arc-shaped groove wall better conforms to the gear meshing rotation trajectory, reducing oil flow resistance and improving the efficiency of oil trapping discharge. Preferably, the center radius of the unloading groove 11 is 8.5-9.5 mm, the groove depth is 1.5-2.5 mm, and the groove width is 2.8-3.2 mm.

[0030] A U-shaped oil guide groove 12 is provided on the inner wall of the wear-resistant sleeve 8 inside the rear cover 3. The oil guide groove 12 extends axially along the wear-resistant sleeve 8, passing through one end of the wear-resistant sleeve 8 near the side plate 9 and the other end near the inner wall of the rear cover 3. The opening of the oil guide groove 12 faces the inner hole of the wear-resistant sleeve 8, and can receive trapped oil flowing into the shaft hole 91 through the unloading groove 11 on the side plate 9. Figure 5 and Figure 6 As shown, the end of the oil guide groove 12 away from the side plate 9 is connected to the oil suction chamber 20, so that trapped oil can flow into the gap of the shaft hole 91 through the unloading groove 11 and into the oil suction chamber 20 through the oil guide groove 12. At the same time, the flowing oil lubricates the drive shaft 4 and the driven shaft 5.

[0031] This invention features an unloading groove 11 located on the side plate 9 of the rear cover 3, precisely aligned with the oil trapping area to ensure timely discharge of trapped oil. Simultaneously, the design of the unloading groove 11 connecting to the shaft hole 91 allows trapped oil to directly enter the mating gap between the shaft and the wear-resistant sleeve 8, directly providing an oil source for the oil guide groove 12. Because the oil guide groove 12 connects to the oil suction chamber 20, a "low-pressure zone" is formed within the shaft hole 91. This negative pressure effect accelerates the flow of trapped oil from the unloading groove 11 into the shaft hole 91. Compared to the traditional method of relying solely on the trapped oil's own pressure for discharge, the oil discharge speed is increased, reducing trapped oil residue. Furthermore, as the oil flows through the oil guide groove 12 into the oil suction chamber 20, it directly acts on the friction contact surfaces of the drive shaft 4, driven shaft 5, and wear-resistant sleeve 8, forming an oil film to achieve shaft lubrication and reduce friction loss.

[0032] The working principle of this utility model is as follows: During the gear meshing process of the gear pump, the first pair of meshing teeth is not completely disengaged while the second pair of meshing teeth has already entered the meshing, forming a closed oil trapping zone. Under the pressure of the gears, the oil in the oil trapping zone flows into the shaft hole 91 through the arc-shaped unloading groove 11 on the side plate 9 of the rear cover 3, which is precisely aligned with the oil trapping zone. Since the oil guide groove 12 is connected to the oil suction chamber 20, a low-pressure zone is formed in the shaft hole 91. The negative pressure effect accelerates the flow of trapped oil from the unloading groove 11 into the shaft hole 91, reducing trapped oil residue. The trapped oil flowing into the shaft hole 91 enters the fitting gap between the drive shaft 4, the driven shaft 5 and the wear-resistant sleeve 8, and then flows back to the oil suction chamber 20 through the U-shaped oil guide groove 12 on the inner wall of the wear-resistant sleeve 8 to complete the recovery. At the same time, during the conveying process of the flowing trapped oil in the oil guide groove 12, it directly acts on the friction contact surface of the drive shaft 4, the driven shaft 5 and the wear-resistant sleeve 8, forming an oil film to achieve shaft lubrication and reduce friction loss.

[0033] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A gear pump with anti-trapped oil lubrication function, characterized in that, The system includes a pump body structure and a gear set. The two ends of the two gear shafts in the gear set are installed in the mounting holes of the pump body structure through wear-resistant sleeves (8). The two end faces of the two gears in the gear set are respectively provided with side plates (9) between them and the inner wall of the pump body structure. The two gear shafts of the gear set pass through the shaft holes (91) of the side plates (9). An unloading groove (11) opposite to the oil trapping area is provided on the side plate (9) on one side of the rear cover (3). The two ends of the unloading groove (11) are connected to the shaft holes (91). An oil guide groove (12) is provided on the inner wall of the wear-resistant sleeve (8) inside the rear cover (3). The end of the oil guide groove (12) away from the side plate (9) is connected to the oil suction chamber (20).

2. A gear pump with anti-trapped oil lubrication function according to claim 1, characterized in that, The unloading groove (11) is an arc-shaped groove, and the oil guide groove (12) is a U-shaped structure. The oil guide groove (12) extends along the axial direction of the wear-resistant sleeve (8), passing through from one end of the wear-resistant sleeve (8) near the side plate (9) to one end near the inner wall of the rear cover (3). The opening of the oil guide groove (12) faces the inner hole of the wear-resistant sleeve (8).

3. A gear pump with anti-trapped oil lubrication function according to claim 2, characterized in that, The pump body structure consists of a pump body (1) and a front cover (2) and a rear cover (3) located on both sides of the pump body. The pump body (1), the front cover (2) and the rear cover (3) are fastened together by connecting bolts.

4. A gear pump with anti-trapped oil lubrication function according to claim 3, characterized in that, The gear set includes a drive shaft (4) and a driven shaft (5), and a drive gear (6) and a driven gear (7) respectively mounted on the drive shaft (4) and the driven shaft (5), and the drive gear (6) and the driven gear (7) are meshed together.

5. A gear pump with anti-trapped oil lubrication function according to claim 4, characterized in that, The two ends of the drive shaft (4) and driven shaft (5) are installed in the front cover (2) and rear cover (3) through wear-resistant sleeves (8). The wear-resistant sleeves (8) are fixedly connected in the mounting holes of the front cover (2) and rear cover (3). The drive shaft (4) and driven shaft (5) are rotatably connected to the inner wall of the wear-resistant sleeves (8). One end of the drive shaft (4) passes through the front cover (2) and is connected to an external power source. A seal (10) is provided at the point where the drive shaft (4) passes through the front cover (2).

6. A gear pump with anti-trapped oil lubrication function according to claim 5, characterized in that, The side plate (9) is positioned by the steps on the inner wall of the pump body (1) and is pressed and fixed by the front cover (2) and the rear cover (3). The end face of the side plate (9) near the gear is in contact with the end face of the driving gear (6) and the driven gear (7).

7. A gear pump with anti-trapped oil lubrication function according to claim 6, characterized in that, The side plate (9) has an 8-shaped structure. Two shaft holes (91) are symmetrically opened along the center line of the width direction of the side plate (9). The shaft holes (91) correspond to the driving shaft (4) and the driven shaft (5). The driving shaft (4) and the driven shaft (5) are respectively located in the two shaft holes (91) and are rotatably connected to the inner wall of the shaft holes (91).

8. A gear pump with anti-trapped oil lubrication function according to claim 4, characterized in that, Both the driving gear (6) and the driven gear (7) adopt a helical gear structure.

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