Hydraulic gear pump for agricultural machinery

Abstract

The utility model discloses a hydraulic gear pump for agricultural machine, including the pump shell, the inside installation of pump shell has two mutually meshed transmission's meshed gear, the front end cover is installed to the front end of pump shell, the rear end cover is installed to the rear end of pump shell, the oil inlet and oil outlet are equipped respectively in the suction chamber and the discharge chamber department on the pump shell, the first inner circulation flow channel and the second inner circulation flow channel are equipped in the pump shell, and the first inner circulation flow channel is linked together with the oil outlet, and the second inner circulation flow channel is linked together with the oil inlet, be equipped with solenoid valve on the rear end cover, and the oil inlet of solenoid valve is linked together with the first inner circulation flow channel, and the oil outlet of solenoid valve is linked together with the second inner circulation flow channel, when the multiway valve is inaction, the oil that the oil outlet flows in the first inner circulation flow channel enters solenoid valve, and from the second inner circulation flow channel, flows back to the oil tank. The utility model can make the multiway valve inaction, open the inner circulation, reduce the pressure loss, reduce the energy consumption.

Description

Technical Field

[0001] This utility model relates to a hydraulic gear pump for agricultural machinery, belonging to the technical field of hydraulic gear pumps. Background Technology

[0002] A gear pump is a rotary pump that transports or pressurizes liquids by relying on the change and movement of the working volume formed between the pump cylinder and meshing gears. It consists of two gears, a pump body, and front and rear covers forming two enclosed spaces. When the gears rotate, the volume of the space on the disengaged side increases, creating a vacuum that draws in the liquid. Conversely, the volume of the space on the meshing side decreases, forcing the liquid into the pipeline. The suction and discharge chambers are separated by the meshing line of the two gears.

[0003] The gear pump supplies oil to the multi-way valve, and then the oil flows back to the oil tank from the multi-way valve. The pipeline of the above hydraulic oil circuit is 1-2 meters long in agricultural tractors. When the multi-way valve is not activated, the gear pump is in an idling state, and the hydraulic oil still needs to flow through the multi-way valve to return to the oil tank. The hydraulic oil loses 0.5-1 MPa of pressure in the above 1-2 meter oil pipe (the lost pressure is eventually converted into heat, causing the hydraulic oil to heat up), thus causing unnecessary energy loss.

[0004] In conclusion, the existing technology obviously has inconveniences and defects in practical use, so it is necessary to improve it. Utility Model Content

[0005] This utility model addresses the shortcomings of the prior art by providing a hydraulic gear pump for agricultural machinery, which enables internal circulation to be activated when the multi-way valve is not in operation, thereby reducing pressure loss and energy consumption.

[0006] To solve the above technical problems, the present invention adopts the following technical solution: A hydraulic gear pump for agricultural machinery includes a pump casing, inside which two meshing gears are installed. A front cover is installed at the front end of the pump casing, and a rear cover is installed at the rear end of the pump casing. An oil inlet and an oil outlet are respectively provided on the pump casing at the suction chamber and the discharge chamber. The pump casing is provided with a first internal circulation channel and a second internal circulation channel. The first internal circulation channel is connected to the oil outlet, and the second internal circulation channel is connected to the oil inlet. A solenoid valve is provided on the rear end cover. The oil inlet of the solenoid valve is connected to the first internal circulation channel, and the oil outlet of the solenoid valve is connected to the second internal circulation channel. When the multi-way valve is not activated, the oil flowing out of the outlet enters the solenoid valve through the first internal circulation channel and flows back to the oil tank through the second internal circulation channel.

[0007] Furthermore, a third internal circulation channel and a fourth internal circulation channel are provided on the rear end cover. The third internal circulation channel is connected to the first internal circulation channel, and the fourth internal circulation channel is connected to the second internal circulation channel.

[0008] Furthermore, the solenoid valve is a two-position two-way valve, with its inlet connected to the inner end of the third internal circulation channel and its outlet connected to the inner end of the fourth internal circulation channel.

[0009] Furthermore, the third and fourth internal circulation channels extend to the inner end face of the rear end cover, and the first and second internal circulation channels extend to the end face where the pump housing mates with the rear end cover.

[0010] Furthermore, the flow port of the third internal circulation channel is opposite to the flow port of the first internal circulation channel, and the flow port of the fourth internal circulation channel is opposite to the flow port of the second internal circulation channel.

[0011] Furthermore, the two-position two-way valve includes a sliding valve core connected to an electromagnetic coil. The sliding valve core is slidably installed in the upper section of the sliding cavity of the two-position two-way valve. The interior of the sliding valve core is a hollow flow channel with an opening at the lower end. The sliding valve core includes a skirt at its lower end. An oil hole communicating with the hollow flow channel is opened on the upper side of the skirt. A third internal circulation flow channel extends to the lower section of the sliding cavity of the two-position two-way valve, and a fourth internal circulation flow channel extends to the sliding valve core of the sliding cavity of the two-position two-way valve. When the sliding valve core is at the bottom dead center, the hydraulic oil enters the lower section of the sliding chamber of the two-position two-way valve from the third internal circulation channel, enters the hollow flow channel from the lower opening of the sliding valve core, and flows from the oil hole to the fourth internal circulation channel. When the sliding valve core is at the top dead center, the skirt blocks the flow port of the fourth internal circulation channel, thereby blocking the internal circulation.

[0012] Furthermore, a stud is threaded onto the lower section of the sliding chamber of the two-position two-way valve, and the lower opening of the sliding valve core is directly opposite the top of the stud. Adjusting the insertion length of the stud adjusts the opening size of the third internal circulation channel.

[0013] Compared with the prior art, the present invention, by adopting the above technical solution, has the following advantages: When the multi-way valve is not activated, the 2-position 2-way valve activates, causing the sliding valve core to move down to the lower dead center, opening the internal circulation circuit. This allows hydraulic oil to flow from the outlet through the first internal circulation channel into the third circulation channel, then through the 2-position 2-way valve, and finally back to the inlet for internal circulation. During internal circulation, the oil circuit circulates within the oil pump, avoiding pressure loss caused by flowing through the multi-way valve, thereby reducing energy consumption.

[0014] The present invention will now be described in detail with reference to the accompanying drawings and embodiments. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is a top view of the present invention; Figure 3 yes Figure 2 Sectional view at point AA along the middle; Figure 4 This is a schematic diagram of the sliding valve core in this utility model; Figure 5 This is a side view of the rear cover; Figure 6 It is a 3D view of the rear end cap; Figure 7 This is a schematic diagram of one side of the pump casing; Figure 8 This is a schematic diagram of the other side of the pump casing; Figure 9 It's an oil circuit diagram.

[0016] In the picture, 1-Pump housing, 2-Meshing gear, 3-Front end cover, 4-Rear end cover, 5-Oil outlet, 6-Oil inlet, 7-First internal circulation channel, 8-Second internal circulation channel, 9-Sliding valve core, 901-Skirt, 10-Stud, 11-Oil hole, 12-Multi-way valve, 13-Oil tank, 14-Two-position two-way valve, 15-Third internal circulation channel, 16-Fourth internal circulation channel. Detailed Implementation

[0017] To provide a clearer understanding of the technical features, objectives, and effects of this utility model, the specific embodiments of this utility model are now described with reference to the accompanying drawings.

[0018] like Figure 1-8 As shown, this utility model provides a hydraulic gear pump for agricultural machinery, including a pump housing 1. Two meshing gears 2 that mesh with each other are installed inside the pump housing 1. A front cover 3 is installed at the front end of the pump housing 1, and a rear cover 4 is installed at the rear end of the pump housing 1. An oil inlet 6 and an oil outlet 5 are respectively provided on the pump housing 1 at the suction chamber and the discharge chamber. The pump casing 1 is provided with a first internal circulation channel 7 and a second internal circulation channel 8. The first internal circulation channel 7 is connected to the oil outlet 5, and the second internal circulation channel 8 is connected to the oil inlet 6. A solenoid valve is provided on the rear cover 4. The oil inlet of the solenoid valve is connected to the first internal circulation channel 7, and the oil outlet of the solenoid valve is connected to the second internal circulation channel 8. When the multi-way valve does not operate, the oil flowing out of the oil outlet 5 enters the solenoid valve through the first internal circulation channel 7, and flows back to the oil tank 13 through the second internal circulation channel 8.

[0019] The rear cover 4 is provided with a third internal circulation channel 15 and a fourth internal circulation channel 16. The third internal circulation channel 15 is connected to the first internal circulation channel 7, and the fourth internal circulation channel 16 is connected to the second internal circulation channel 8.

[0020] The solenoid valve is a two-position two-way valve 14. The oil inlet of the two-position two-way valve 14 is connected to the inner end of the third internal circulation channel 15, and the oil outlet of the two-position two-way valve 14 is connected to the inner end of the fourth internal circulation channel 16.

[0021] The third internal circulation channel 15 and the fourth internal circulation channel 16 extend to the inner end face of the rear end cover 4, such as Figure 6 The first internal circulation channel 7 and the second internal circulation channel 8 extend to the end face of the pump casing 1 that mates with the rear end cover 4, as shown below. Figure 7 The flow port of the third internal circulation channel 15 is opposite to the flow port of the first internal circulation channel 7, and the flow port of the fourth internal circulation channel 16 is opposite to the flow port of the second internal circulation channel 8.

[0022] The two-position two-way valve 14 includes a sliding valve core 9 connected to an electromagnetic coil. The sliding valve core 9 is slidably mounted on the upper section of the sliding cavity of the two-position two-way valve 14. The interior of the sliding valve core 9 is a hollow flow channel with an opening at the lower end. The sliding valve core 9 includes a skirt 901 disposed at its lower end. An oil hole 11 communicating with the hollow flow channel is opened on the upper side of the skirt 901. The third internal circulation flow channel 15 extends to the lower section of the sliding cavity of the two-position two-way valve 14, and the fourth internal circulation flow channel 16 extends to the sliding valve core 9 of the sliding cavity of the two-position two-way valve 14. When the sliding valve core 9 is at the lower dead point, hydraulic oil enters the lower section of the sliding cavity of the two-position two-way valve 14 from the third internal circulation flow channel 15, enters the hollow flow channel from the lower opening of the sliding valve core 9, and flows to the fourth internal circulation flow channel 16 from the oil hole 11. When the sliding valve core 9 is at the upper dead point, the skirt 901 blocks the flow port of the fourth internal circulation flow channel 16, thereby blocking the internal circulation.

[0023] The lower section of the sliding chamber of the two-position two-way valve 14 is threaded with a stud 10, and the lower opening of the sliding valve core 9 is directly opposite the top of the stud 10. Adjusting the insertion length of the stud 10 adjusts the opening of the third internal circulation channel 15.

[0024] The specific working principle of this utility model: like Figure 9 When the multi-way valve 12 drives the actuator to operate, the internal circulation is blocked, and the hydraulic oil returns directly to the oil tank 13 through the multi-way valve 12. When the multi-way valve 12 does not operate, the two-position two-way valve 14 operates, causing the sliding valve core 9 to move down to the lower dead point, opening the internal circulation circuit, so that the hydraulic oil enters the third circulation channel 15 from the oil outlet 5 through the first internal circulation channel 7, flows through the two-position two-way valve 14, then flows to the second internal circulation channel 8, and finally flows back to the oil inlet 6 to perform internal circulation. In the internal circulation, the oil circuit circulates inside the oil pump, avoiding the pressure loss caused when flowing through the multi-way valve 12, thereby reducing energy consumption.

[0025] Preferably, during the internal circulation process, the insertion length of the adjusting stud 10 is adjusted to regulate the opening of the third internal circulation channel 15, so that four-fifths of the oil flows through the internal circulation oil circuit, and the remaining one-fifth flows to the multi-way valve 12 and then back to the oil tank 13. The one-fifth of the hydraulic oil flowing through the multi-way valve 12 serves to dissipate heat and prevent the oil temperature from becoming too high during the internal circulation process.

[0026] The above description provides examples of the preferred embodiments of this utility model. Any aspects not detailed herein are common knowledge to those skilled in the art. The scope of protection of this utility model is determined by the claims. Any equivalent modifications based on the technical teachings of this utility model are also within the scope of protection of this utility model.

Claims

1. A hydraulic gear pump for agricultural machinery, comprising a pump housing (1), wherein two meshing gears (2) are installed inside the pump housing (1) for mutual meshing and transmission, a front end cover (3) is installed at the front end of the pump housing (1), a rear end cover (4) is installed at the rear end of the pump housing (1), and an oil inlet (6) and an oil outlet (5) are respectively provided on the pump housing (1) at the suction chamber and the discharge chamber, characterized in that: The pump casing (1) is provided with a first internal circulation channel (7) and a second internal circulation channel (8). The first internal circulation channel (7) is connected to the oil outlet (5), and the second internal circulation channel (8) is connected to the oil inlet (6). A solenoid valve is provided on the rear cover (4). The oil inlet of the solenoid valve is connected to the first internal circulation channel (7), and the oil outlet of the solenoid valve is connected to the second internal circulation channel (8). When the multi-way valve (12) is not activated, the oil flowing out of the outlet (5) enters the solenoid valve through the first internal circulation channel (7) and flows back to the oil tank (13) through the second internal circulation channel (8).

2. The hydraulic gear pump for agricultural machinery as described in claim 1, characterized in that: The rear cover (4) is provided with a third internal circulation channel (15) and a fourth internal circulation channel (16). The third internal circulation channel (15) is connected to the first internal circulation channel (7), and the fourth internal circulation channel (16) is connected to the second internal circulation channel (8).

3. The hydraulic gear pump for agricultural machinery as described in claim 2, characterized in that: The solenoid valve is a two-position two-way valve (14). The oil inlet of the two-position two-way valve (14) is connected to the inner end of the third internal circulation channel (15), and the oil outlet of the two-position two-way valve (14) is connected to the inner end of the fourth internal circulation channel (16).

4. A hydraulic gear pump for agricultural machinery as described in claim 3, characterized in that: The third internal circulation channel (15) and the fourth internal circulation channel (16) extend to the inner end face of the rear end cover (4), and the first internal circulation channel (7) and the second internal circulation channel (8) extend to the end face of the pump housing (1) that mates with the rear end cover (4).

5. A hydraulic gear pump for agricultural machinery as described in claim 4, characterized in that: The flow port of the third internal circulation channel (15) is opposite to the flow port of the first internal circulation channel (7), and the flow port of the fourth internal circulation channel (16) is opposite to the flow port of the second internal circulation channel (8).

6. A hydraulic gear pump for agricultural machinery as described in claim 3, characterized in that: The two-position two-way valve (14) includes a sliding valve core (9) connected to an electromagnetic coil. The sliding valve core (9) is slidably installed in the upper section of the sliding cavity of the two-position two-way valve (14). The interior of the sliding valve core (9) is a hollow flow channel with an opening at the lower end. The sliding valve core (9) includes a skirt (901) located at its lower end. An oil hole (11) communicating with the hollow flow channel is opened on the upper side of the skirt (901). The third internal circulation flow channel (15) extends to the lower section of the sliding cavity of the two-position two-way valve (14). The fourth internal circulation flow channel (16) extends to the sliding valve core (9) of the sliding cavity of the two-position two-way valve (14). When the sliding valve core (9) is at the bottom dead center, the hydraulic oil enters the lower section of the sliding chamber of the two-position two-way valve (14) from the third internal circulation channel (15), enters the hollow flow channel from the lower opening of the sliding valve core (9), and flows from the oil hole (11) to the fourth internal circulation channel (16). When the sliding valve core (9) is at the top dead center, the skirt (901) blocks the flow port of the fourth internal circulation channel (16), thereby blocking the internal circulation.

7. A hydraulic gear pump for agricultural machinery as described in claim 6, characterized in that: The lower section of the sliding chamber of the two-position two-way valve (14) is threaded with a stud (10), and the lower opening of the sliding valve core (9) is directly opposite the top of the stud (10). Adjusting the insertion length of the stud (10) adjusts the opening of the third internal circulation channel (15).

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