A hydraulic rotary oil replenishment system

Abstract

The present invention discloses a hydraulic rotary oil replenishment system, comprising: a controller, an oil tank, a hydraulic pump, a first reversing valve, a rotary motor, a first pressure sensor, an oil replenishment control valve, an accumulator and an oil replenishment source, wherein the hydraulic pump is connected to the rotary motor through the first reversing valve, the accumulator is connected to the rotary motor through the oil replenishment control valve, the first pressure sensor is connected to the oil circuit between the first reversing valve and the rotary motor, the controller is connected to the first pressure sensor and the oil replenishment control valve, and the controller is also connected to the rotary motor. The hydraulic oil output from the oil replenishment source replenishes the hydraulic oil to the accumulator through the oil replenishment control valve, when the first reversing valve is closed and the first pressure sensor detects low pressure, the controller controls the oil replenishment control valve to open, and the hydraulic oil stored in the accumulator quickly replenishes the oil to the rotary motor through the oil replenishment control valve, thereby avoiding the rotary motor from sucking air, thereby improving the service life of the components of the hydraulic rotary system.

Description

Technical Field

[0001] The invention relates to the field of hydraulic technology, and in particular to a hydraulic rotary oil replenishing system. Background Art

[0002] During the operation of rotary actuators such as hydraulic motors, the problem of cavitation caused by untimely oil replenishment in the system is one of the important reasons that affect the life of the components and even cause system failures. Rotary actuators and their loads have a certain inertia. When the main oil circuit is cut off by the control valve, the load still rotates at a certain speed due to inertia. At this time, due to the cut-off of the oil supply of the main oil circuit, the pressure of the rotary actuator oil inlet circuit drops rapidly, and cavitation is prone to occur. In the conventional hydraulic excavator rotary system, when the rotary platform brakes, it will maintain a rotating trend under the action of the platform inertia, causing the oil outlet pressure to rise rapidly and exceed the set pressure of the relief valve. The high-pressure oil flows to the rotary motor oil inlet through the relief valve and the check valve to achieve oil replenishment.

[0003] However, in the excavator's rotary energy recovery system that uses hydraulic energy storage, since the high-pressure oil on the brake side is recovered and stored in the high-pressure accumulator, the conventional back-pressure oil return method has a low oil replenishment pressure, making it difficult to achieve rapid oil replenishment, which can easily cause motor air absorption problems. Summary of the invention

[0004] The object of the present invention is to provide a hydraulic rotary oil replenishing system which can replenish oil in a timely and effective manner to avoid damage to components caused by cavitation.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A hydraulic rotary oil replenishment system comprises: a controller, an oil tank, a hydraulic pump, a first reversing valve, a rotary motor, a first pressure sensor, an oil replenishment control valve, an accumulator and an oil replenishment source, wherein the hydraulic pump is connected to the rotary motor via the first reversing valve, the accumulator is connected to the rotary motor via the oil replenishment control valve, the hydraulic pump is used to transport the hydraulic oil in the oil tank to the rotary motor via the first reversing valve, the oil replenishment source is used to replenish the hydraulic oil to the accumulator, the first pressure sensor is connected to the oil circuit between the first reversing valve and the rotary motor, the controller is connected to the first pressure sensor and the oil replenishment control valve, and the controller is used to control the oil replenishment control valve to open when the first pressure sensor detects low pressure.

[0007] Preferably, the oil replenishment control valve comprises a first one-way valve, a second reversing valve and a throttle valve, the oil replenishment source is connected to the accumulator via the throttle valve, and the accumulator is connected to the rotary motor via the second reversing valve and the first one-way valve in turn.

[0008] Preferably, the hydraulic rotary oil replenishing system further comprises a first overflow valve, and the first overflow valve is connected in parallel with the rotary motor.

[0009] Preferably, the hydraulic rotary oil replenishing system further comprises a second overflow valve, and the second overflow valve is connected to the accumulator.

[0010] Preferably, the hydraulic rotary oil replenishing system further includes a pilot pump, a shuttle valve and a rotary handle valve, the pilot pump is connected to the rotary handle valve, the rotary handle valve is connected in parallel with the shuttle valve, and the shuttle valve is connected in parallel with two reversing ends of the first reversing valve.

[0011] Preferably, it further comprises a second pressure sensor, wherein the second pressure sensor is connected to the shuttle valve and the controller.

[0012] Preferably, the first reversing valve is a hydraulically controlled reversing valve or an electrically controlled reversing valve.

[0013] Preferably, the replenishing oil source is the hydraulic pump or the pilot pump.

[0014] Preferably, the hydraulic swing oil replenishing system further comprises a swing motor braking energy recovery device connected in parallel with the swing motor.

[0015] Preferably, the hydraulic rotary oil replenishment system also includes a rotary valve group connected in parallel with the rotary motor, the rotary valve group includes a third overflow valve, a fourth overflow valve, a third check valve and a fourth check valve, the third overflow valve and the fourth overflow valve are interconnected and connected in parallel with the rotary motor, the third check valve and the fourth check valve are connected to each other and connected in parallel with the rotary motor, the oil replenishment control valve is connected to the oil circuit of the third check valve and the fourth check valve, and is also connected to the oil circuit of the third overflow valve and the fourth overflow valve.

[0016] Compared with the prior art, the above technical solution has the following advantages:

[0017] The hydraulic rotary oil replenishment system provided by the present invention includes: a controller, an oil tank, a hydraulic pump, a first reversing valve, a rotary motor, a first pressure sensor, an oil replenishment control valve, an accumulator and an oil replenishment source. The hydraulic pump is connected to the rotary motor through the first reversing valve, the accumulator is connected to the rotary motor through the oil replenishment control valve, the first pressure sensor is connected to the oil circuit between the first reversing valve and the rotary motor, the controller is connected to the first pressure sensor and the oil replenishment control valve, and the controller is also connected to the rotary motor. The hydraulic oil output by the oil replenishment source replenishes the hydraulic oil to the accumulator through the oil replenishment control valve. When the first reversing valve is closed and the first pressure sensor detects low pressure, the controller controls the oil replenishment control valve to open, and the hydraulic oil stored in the accumulator quickly replenishes the rotary motor through the oil replenishment control valve, thereby avoiding the rotary motor from sucking air, thereby improving the service life of the components of the hydraulic rotary system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0019] Figure 1 A structural schematic diagram of a hydraulic rotary oil replenishing system provided by a specific embodiment of the present invention;

[0020] Figure 2 A structural schematic diagram of a hydraulic rotary oil replenishing system provided in another specific embodiment of the present invention.

[0021] The reference numerals are as follows:

[0022] 1 is a controller, 2 is an oil tank, 3 is a back pressure valve, 4 is a hydraulic pump, 5 is a pilot pump, 6 is a second pressure sensor, 7 is a shuttle valve, 8 is a swing handle valve, 9 is a first reversing valve, 10 is a first overflow valve, 11 is a swing motor, 12 is a swing load, 13 is a first pressure sensor, 14 is an oil replenishment control valve, 141 is a first check valve, 142 is a second reversing valve, 143 is a throttle valve, 15 is an oil replenishment source, 16 is an accumulator, 17 is a second check valve, 18 is a second overflow valve, 19 is a swing valve group, 191 is a third check valve, 192 is a fourth check valve, 193 is a third overflow valve, 194 is a fourth overflow valve, and 20 is a brake energy recovery device for a swing motor. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Please refer to Figure 1 , Figure 1 A structural schematic diagram of a hydraulic rotary oil replenishing system provided in a specific embodiment of the present invention.

[0025] A hydraulic rotary oil replenishment system provided in an embodiment of the present invention comprises: a controller 1, an oil tank 2, a hydraulic pump 4, a first reversing valve 9, a rotary motor 11, a first pressure sensor 13, an oil replenishment control valve 14, an accumulator 16 and an oil replenishment source 15, wherein the hydraulic pump 4 is connected to the rotary motor 11 through the first reversing valve 9, and the rotary motor 11 is connected to the rotary load 12, such as Figure 1 As shown, the C port of the rotary motor 11 is connected to the A port of the first reversing valve 9, the D port of the rotary motor 11 is connected to the B port of the first reversing valve 9, the P port of the first reversing valve 9 is connected to the hydraulic pump 4, the T port of the first reversing valve 9 is connected to the oil tank 2 through the back pressure valve 3, the accumulator 16 is connected to the rotary motor 11 through the oil replenishment control valve 14, and the first pressure sensor 13 is connected to the oil circuit between the first reversing valve 9 and the rotary motor 11, as shown in FIG. Figure 1 As shown, the first pressure sensor 13 is connected between the C port and the A port, the controller 1 is connected to the first pressure sensor 13 and the oil replenishment control valve 14 , and the controller 1 is also connected to the rotary motor 11 .

[0026] In the initial state of the system, the rotary motor 11 is in a stationary state, and the first reversing valve 9 is in the middle working position. When starting to work, the first reversing valve 9 is in the left working position. At this time, the hydraulic oil output by the hydraulic pump 4 passes through the first reversing valve 9 to the C port of the rotary motor 11, and the rotary motor 11 is turned on. Figure 1 The rotation is accelerated clockwise in the direction shown, and the hydraulic oil output by the replenishing oil source 15 replenishes the hydraulic oil to the accumulator 16 through the replenishing oil control valve 14. When the first reversing valve 9 is closed, the pressure on the C side of the swing motor 11 decreases rapidly. When the first pressure sensor 13 detects low pressure, the controller 1 controls the replenishing oil control valve 14 to open, and the hydraulic oil stored in the accumulator 16 replenishes the C side of the swing motor 11 rapidly through the replenishing oil control valve 14, thereby avoiding the cavitation phenomenon of the swing motor 11, thereby improving the service life of the components of the hydraulic swing system.

[0027] In some embodiments, the oil replenishment control valve 14 includes a first one-way valve 141, a second reversing valve and a throttle valve 143. The oil replenishment source 15 is connected to the accumulator 16 through the throttle valve 143. The throttle valve 143 can be replaced by a fixed damper. The accumulator 16 is connected to the rotary motor 11 through the second reversing valve and the first one-way valve 141 in sequence. The hydraulic rotary oil replenishment system also includes a first relief valve 10 and a second relief valve 18. The first relief valve 10 is connected in parallel with the rotary motor 11, and the second relief valve 18 is connected to the accumulator 16. When the pressure exceeds the pressure set by the first relief valve 10, part of the high-pressure oil output by the hydraulic pump 4 flows out from the first relief valve 10. Under the action of the first one-way valve 141, the high-pressure oil output by the hydraulic pump 4 cannot pass through the oil replenishment control valve 14. The hydraulic oil output from the replenishing oil source 15 is used to charge the accumulator 16 via the throttle valve 143. Due to the throttling effect of the throttle valve 143, the accumulator 16 is slowly charged. When the outlet pressure of the accumulator 16 reaches the set maximum pressure, the hydraulic oil will overflow from the second relief valve 18, thereby avoiding overcharging of the accumulator 16.

[0028] In some embodiments, the hydraulic rotary oil replenishment system further includes a pilot pump 5, a second pressure sensor 6, a shuttle valve 7 and a rotary handle valve 8, the pilot pump 5 is connected to the rotary handle valve 8, the rotary handle valve 8 is connected in parallel to the shuttle valve 7, the shuttle valve 7 is connected in parallel to the two reversing ends of the first reversing valve 9, and the second pressure sensor 6 is connected to the shuttle valve 7 and the controller 1. The reversing of the first reversing valve 9 can be controlled by the pilot pump 5, the rotary handle valve 8 and the shuttle valve 7. In addition to using hydraulic pressure to control the reversing of the first reversing valve 9, the first reversing valve 9 can also be selected as an electrically controlled reversing valve. The oil replenishment source 15 is a hydraulic pump 4 or a pilot pump 5.

[0029] In some embodiments, Figure 2 As shown, the hydraulic swing oil replenishing system further includes a swing motor braking energy recovery device 20 connected in parallel with the swing motor 11. The swing motor braking energy recovery device 20 can recover the braking energy of the hydraulic swing system.

[0030] In some embodiments, Figure 2 As shown, the hydraulic rotary oil replenishing system also includes a rotary valve group 19 connected in parallel with the rotary motor 11, the rotary valve group 19 includes a third one-way valve 191, a fourth one-way valve 192, a third overflow valve 193, and a fourth overflow valve 194. The third overflow valve 193 and the fourth overflow valve 194 are interconnected and connected in parallel with the rotary motor 11, the third one-way valve 191 and the fourth one-way valve 192 are interconnected and connected in parallel with the rotary motor 11, and the oil replenishing control valve 14 is connected to the oil circuit of the third one-way valve 191 and the fourth one-way valve 192, and is also connected to the oil circuit of the third overflow valve 193 and the fourth overflow valve 194.

[0031] The working method of a hydraulic rotary oil replenishing system provided by an embodiment of the present invention is as follows:

[0032] Step S1: the controller 1 receives a signal PC from the first pressure sensor 13 and a signal Pi from the second pressure sensor 6;

[0033] Step S2: Determine whether PC is less than PC1, where PC1 is a preset oil replenishment pressure. If yes, proceed to step S6, open the second reversing valve 142, and replenish oil from the oil replenishment system to the rotary system; if no, proceed to step S3.

[0034] Step S3: Determine whether Pi is less than Pi1, where Pi1 is a preset swing pilot control pressure. If yes, proceed to step S6 to open the second reversing valve 142; if no, proceed to step S4.

[0035] Step S4: Determine whether Pw is less than α, where Pw is the rate of change of the output signal Pi of the second pressure sensor 6 and α is a preset rate of change. If yes, proceed to step S6 to open the second reversing valve 142; if no, proceed to step S5.

[0036] Step S5: close the second reversing valve 142.

[0037] Step S6: Open the second reversing valve 142.

[0038] It should be noted that, in this specification, relational terms such as first and second are merely used to distinguish one entity from other entities, but do not necessarily require or imply any actual relationship or order between these entities.

[0039] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0040] The above is a detailed introduction to a hydraulic rotary oil replenishing system provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A hydraulic rotary oil replenishment system, characterized in that: include: A controller (1), an oil tank (2), a hydraulic pump (4), a first reversing valve (9), a rotary motor (11), a first pressure sensor (13), an oil replenishment control valve (14), an accumulator (16), and an oil replenishment source (15), wherein the hydraulic pump (4) is connected to the rotary motor (11) via the first reversing valve (9), the accumulator (16) is connected to the rotary motor (11) via the oil replenishment control valve (14), the hydraulic pump (4) is used to transport the hydraulic oil in the oil tank (2) to the rotary motor (11) via the first reversing valve (9), the oil replenishment source (15) is used to replenish the hydraulic oil to the accumulator (16), and the first pressure sensor (13) is connected to the In the oil circuit between the first reversing valve (9) and the rotary motor (11), the controller (1) is connected to the first pressure sensor (13) and the oil replenishment control valve (14). The controller (1) is used to control the oil replenishment control valve (14) to open when the first pressure sensor (13) detects low pressure. The oil replenishment control valve (14) comprises a first check valve (141), a second reversing valve (142) and a throttle valve (143). The oil replenishment source (15) is connected to the accumulator (16) via the throttle valve (143). The accumulator (16) is connected to the rotary motor (11) via the second reversing valve (142) and the first check valve (141) in sequence. It also comprises a pilot pump (5), a shuttle valve (7) and a rotary handle valve (8), wherein the pilot pump (5) is connected to the rotary handle valve (8), the rotary handle valve (8) is connected in parallel to the shuttle valve (7), and the shuttle valve (7) is connected in parallel to two reversing ends of the first reversing valve (9); It also includes a first overflow valve (10), wherein the first overflow valve (10) is connected in parallel with the rotary motor (11); It also includes a second overflow valve (18), wherein the second overflow valve (18) is connected to the accumulator (16); It also includes a second pressure sensor (6), wherein the second pressure sensor (6) is connected to the shuttle valve (7) and the controller (1); The oil replenishment source (15) is the hydraulic pump (4) or the pilot pump (5); It also includes a rotary motor braking energy recovery device (20) connected in parallel with the rotary motor (11); Alternatively, the invention further comprises a rotary valve group (19) connected in parallel with the rotary motor (11), the rotary valve group (19) comprising a third one-way valve (191), a fourth one-way valve (192), a third overflow valve (193) and a fourth overflow valve (194), the third overflow valve (193) and the fourth overflow valve (194) being connected to each other and connected in parallel with the rotary motor (11), the third one-way valve (191) and the fourth one-way valve (192) being connected to each other and connected in parallel with the rotary motor (11), the oil replenishment control valve (14) being connected to the oil circuits of the third one-way valve (191) and the fourth one-way valve (192), and also being connected to the oil circuits of the two third overflow valves (193) and the fourth overflow valve (194); The controller (1) receives a signal PC from the first pressure sensor (13) and a signal Pi from the second pressure sensor (6), and determines whether PC is less than PC1, where PC1 is a preset oil replenishment pressure. If so, the second reversing valve (142) is opened to replenish oil from the oil replenishment system to the rotary system; if not, it is determined whether Pi is less than Pi1, where Pi1 is a preset rotary pilot control pressure; if so, the second reversing valve (142) is opened; if not, it is determined whether Pw is less than α, where Pw is a change rate of the output signal Pi of the second pressure sensor (6), and α is a preset change rate; if so, the second reversing valve (142) is opened; if not, the second reversing valve (142) is closed.

2. The hydraulic rotary oil replenishing system according to claim 1, characterized in that: The first reversing valve (9) is a hydraulically controlled reversing valve or an electrically controlled reversing valve.

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