A differential oil circuit for telescopic arms of aerial work vehicles

Abstract

The utility model relates to a differential oil circuit for a telescopic arm of an aerial work vehicle. The utility model includes an electromagnetic reversing valve, a two-way balancing valve and a telescopic oil cylinder, wherein a rodless chamber and a rod chamber are arranged in the telescopic oil cylinder, and the structural features thereof are: it also includes a rodless chamber main circuit, a rod chamber main circuit, a rodless chamber bypass and a rod chamber bypass, wherein one end of the rodless chamber main circuit is connected with the rodless chamber, one end of the rod chamber main circuit is connected with the rod chamber, the other end of the rodless chamber main circuit is connected with the other end of the rod chamber main circuit, and the other end of the rodless chamber main circuit and the other end of the rod chamber main circuit are both controlled by an electromagnetic reversing valve, a first balancing valve core is installed on the rodless chamber main circuit, a second balancing valve core is installed on the rod chamber main circuit, a first non-return valve is installed on the rodless chamber bypass, a second non-return valve is installed on the rod chamber bypass, and the second balancing valve core is connected with the balancing valve control oil circuit.

Description

Technical Field

[0001] The utility model relates to a differential oil circuit for a telescopic arm of an aerial work vehicle, which is mainly used for improving the extension speed of the telescopic arm of a telescopic arm type aerial work vehicle. Background Art

[0002] The telescopic arm of a telescopic boom aerial work vehicle is generally driven by a telescopic cylinder, and the movement speed of the telescopic cylinder determines the speed of the telescopic arm; the telescopic cylinder is generally longer. In order to ensure the rigidity of the piston rod when the telescopic arm is extended, the rod diameter will be larger, and the cylinder diameter will increase accordingly, resulting in a larger flow demand when extending. The working pressure is relatively small compared to the boom ups and downs cylinder, and is much smaller than the rated pressure of the hydraulic system.

[0003] At present, the flow rate required for the extension of the telescopic cylinder in a telescopic boom aerial work vehicle is generally the maximum flow rate of the entire vehicle's upper movement. Most models increase the hydraulic pump flow rate by increasing the engine speed, thereby increasing the extension speed of the telescopic arm. The engine's fuel consumption and noise are relatively large. There are methods on the market that achieve differential speed increase by customizing a special differential balancing valve group, but the cost is relatively high, and the improved balancing valve block is larger in size than before, making it difficult to arrange the position, and is not widely used, making it unsuitable for promotion and use. There are also methods that achieve differential speed increase by adding a shuttle valve or an additional electromagnetic switching valve in the telescopic arm control circuit, but the oil circuit connection is complex and the pressure loss is large. Utility Model Content

[0004] The purpose of the utility model is to overcome the above-mentioned deficiencies in the prior art and to provide a differential oil circuit with a reasonable structural design for a telescopic arm of an aerial work vehicle.

[0005] The technical solution adopted by the utility model to solve the above-mentioned problem is: the differential oil circuit for the telescopic arm of the aerial work vehicle comprises an electromagnetic reversing valve, a two-way balancing valve and a telescopic oil cylinder, and a rodless chamber and a rod chamber are arranged in the telescopic oil cylinder, and its structural characteristics are: it also comprises a rodless chamber main circuit, a rod chamber main circuit, a rodless chamber bypass and a rod chamber bypass, one end of the rodless chamber main circuit is connected with the rodless chamber, one end of the rod chamber main circuit is connected with the rod chamber, the other end of the rodless chamber main circuit is connected with the other end of the rod chamber main circuit, and the other end of the rodless chamber main circuit and the other end of the rod chamber main circuit are both controlled by the electromagnetic reversing valve, a first balancing valve core is installed on the rodless chamber main circuit, a second balancing valve core is installed on the rod chamber main circuit, a first one-way valve is installed on the rodless chamber bypass, a second one-way valve is installed on the rod chamber bypass, and the second balancing valve core is connected to the balancing valve control oil circuit.

[0006] Furthermore, a first valve block oil outlet and a first valve block oil inlet are provided on the rodless chamber main circuit, and the first valve block oil outlet and the first valve block oil inlet are respectively connected to the two ends of the rodless chamber bypass, and a second valve block oil outlet and a second valve block oil inlet are provided on the rod chamber main circuit, and the second valve block oil outlet and the second valve block oil inlet are respectively connected to the two ends of the rod chamber bypass.

[0007] Further, the first balancing valve core is located between the oil outlet of the first valve block and the oil inlet of the first valve block, and the second balancing valve core is located between the oil outlet of the second valve block and the oil inlet of the second valve block.

[0008] Further, one end of the balancing valve control oil circuit is communicated with the oil inlet of the first valve block, and the other end of the balancing valve control oil circuit is communicated with the second balancing valve core.

[0009] Furthermore, the electromagnetic reversing valve is provided with a first oil outlet, a second oil outlet, an oil inlet and an oil return port, and the other end of the rodless chamber main path and the other end of the rod chamber main path are respectively connected to the first oil outlet and the second oil outlet.

[0010] Furthermore, the electromagnetic reversing valve is provided with a first electromagnet and a second electromagnet.

[0011] Compared with the prior art, the utility model has the following advantages: it adopts the electromagnetic reversing valve function that can realize differential connection and the second balancing valve core suitable for the differential oil circuit on the rod chamber side, without changing the valve block and the telescopic cylinder; when the electromagnetic reversing valve is switched to the extended position, the telescopic cylinder is differentially connected, and the hydraulic oil in the rod chamber and the pressure oil of the second oil outlet flow to the rodless chamber together, and the telescopic cylinder runs quickly, driving the telescopic arm to extend quickly; the use of a differential speed-increasing oil circuit can make the telescopic arm extension speed-increasing effect significant, without the need to add an additional high throttle, with good versatility, wide application range, energy saving and environmental protection. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic diagram of the flow of pressure oil when the telescopic arm of the embodiment of the utility model is extended.

[0013] In the figure: electromagnetic reversing valve 1, two-way balancing valve 2, telescopic cylinder 3, rodless chamber main line 4, rod chamber main line 5, rodless chamber bypass 6, rod chamber bypass 7,

[0014] Balance valve control oil circuit 2.1, first balance valve core 2.2, first check valve 2.3, second check valve 2.4, second balance valve core 2.5,

[0015] Rodless cavity 3.1, rod cavity 3.2,

[0016] First oil outlet A, second oil outlet B, oil inlet P, oil return port T, first electromagnet E, second electromagnet F,

[0017] The first valve block oil inlet V1, the second valve block oil inlet V2, the first valve block oil outlet C1, the second valve block oil outlet C2. DETAILED DESCRIPTION

[0018] The present invention will be further described in detail below with reference to the accompanying drawings and through examples. The following examples are provided to explain the present invention, but the present invention is not limited to the following examples.

[0019] Example

[0020] See also Figure 1 As shown, it should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the utility model, so they have no substantial technical significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the utility model, should still fall within the scope of the technical content disclosed by the utility model. At the same time, if there are references to terms such as "upper", "lower", "left", "right", "middle" and "one" in this specification, they are only for the convenience of description, and are not used to limit the scope of the implementation of the utility model. The change or adjustment of their relative relationship, without substantially changing the technical content, should also be regarded as the scope of the implementation of the utility model.

[0021] The differential oil circuit for the telescopic arm of the aerial work vehicle in this embodiment includes an electromagnetic reversing valve 1, a two-way balancing valve 2, a telescopic oil cylinder 3, a rodless cavity main circuit 4, a rod cavity main circuit 5, a rodless cavity bypass 6 and a rod cavity bypass 7. A rodless cavity 3.1 and a rod cavity 3.2 are arranged in the telescopic oil cylinder 3. One end of the rodless cavity main circuit 4 is connected to the rodless cavity 3.1, one end of the rod cavity main circuit 5 is connected to the rod cavity 3.2, the other end of the rodless cavity main circuit 4 is connected to the other end of the rod cavity main circuit 5, and the other end of the rodless cavity main circuit 4 is connected to the rod cavity main circuit The other end of 5 is controlled by the electromagnetic reversing valve 1, a first balancing valve core 2.2 is installed on the rodless chamber main circuit 4, a second balancing valve core 2.5 is installed on the rod chamber main circuit 5, a first non-return valve 2.3 is installed on the rodless chamber bypass 6, a second non-return valve 2.4 is installed on the rod chamber bypass 7, and the second balancing valve core 2.5 is connected to the balancing valve control oil circuit 2.1, that is, one end of the balancing valve control oil circuit 2.1 is connected to the oil inlet V1 of the first valve block, and the other end of the balancing valve control oil circuit 2.1 is connected to the second balancing valve core 2.5.

[0022] In this embodiment, the rodless chamber main path 4 is provided with a first valve block oil outlet C1 and a first valve block oil inlet V1, and the first valve block oil outlet C1 and the first valve block oil inlet V1 are respectively connected to the two ends of the rodless chamber bypass 6, and the rod chamber main path 5 is provided with a second valve block oil outlet C2 and a second valve block oil inlet V2, and the second valve block oil outlet C2 and the second valve block oil inlet V2 are respectively connected to the two ends of the rod chamber bypass 7, the first balancing valve core 2.2 is located between the first valve block oil outlet C1 and the first valve block oil inlet V1, and the second balancing valve core 2.5 is located between the second valve block oil outlet C2 and the second valve block oil inlet V2.

[0023] The solenoid reversing valve 1 in this embodiment is provided with a first oil outlet A, a second oil outlet B, an oil inlet P, an oil return port T, a first electromagnet E and a second electromagnet F. The other end of the rodless chamber main path 4 and the other end of the rod chamber main path 5 are connected to the first oil outlet A and the second oil outlet B respectively.

[0024] Specifically, see Figure 1 The electromagnetic reversing valve 1 is a three-position four-way electromagnetic reversing valve. The right position of the electromagnetic reversing valve 1 has a differential connection function. The rod cavity side of the two-way balancing valve 2 adopts a second balancing valve core 2.5 suitable for differential connection, that is, when the pressure of the balancing valve control oil circuit 2.1 is equal to the pressure of the second oil outlet B, the second balancing valve core 2.5 can be opened unidirectionally to pass oil.

[0025] When the second electromagnet F of the electromagnetic reversing valve 1 is energized, see Figure 1 , the electromagnetic reversing valve 1 switches to the right position, and the pressure oil enters the first oil outlet A and the second oil outlet B from the oil inlet P at the same time. The pressure oil enters the rodless chamber 3.1 of the telescopic cylinder 3 through the first one-way valve 2.3. At the same time, the pressure oil opens the second balance valve core 2.5 through the balance valve control oil circuit 2.1, and uses the area difference between the rodless chamber 3.1 and the rod chamber 3.2 of the telescopic cylinder 3 to form a thrust, pushing the piston rod to move in the extension direction. The hydraulic oil in the rod chamber 3.2 of the telescopic cylinder 3 and the pressure oil flowing in from the oil inlet P flow to the rodless chamber 3.1 of the telescopic cylinder 3 together, and the telescopic arm is quickly extended. The above description is the process of extending the telescopic arm. The process of retracting the telescopic arm and the non-working state are all prior art, which will not be repeated here.

[0026] Assuming that the flow rate of the oil inlet P is Q, the effective action areas of the rodless chamber 3.1 and the rod chamber 3.2 of the telescopic oil cylinder 3 are A1 and A2 respectively, when the differential oil circuit is used, the movement speed of the telescopic oil cylinder piston is v1=Q / (A1-A2). If the speed-increasing differential circuit is not used, the movement speed of the telescopic oil cylinder piston is v2=Q / A1, v1>v2, and it can be seen that the speed is significantly improved; it is worth noting that as the speed increases, as the effective action area changes from A1 to A1-A2, the working pressure P = load F÷action area A, when the load F is the same, the action area A decreases and the working pressure P increases. When the working pressure P is less than the rated pressure of the system, after the differential speed-increasing oil circuit is used, the working pressure will increase appropriately during extension, but it will not exceed the rated pressure of the system, and a smaller hydraulic pump output flow can be used to obtain a larger extension speed. This method is feasible.

[0027] In addition, it should be noted that the shapes and names of the parts and components of the specific embodiments described in this specification may be different, and the above content described in this specification is only an example of the structure of the utility model. All equivalent changes or simple changes made based on the structure, features and principles described in the patent concept of the utility model are included in the protection scope of the utility model patent. Technicians in the technical field of the utility model can make various modifications or supplements to the specific embodiments described or replace them in a similar manner, as long as they do not deviate from the structure of the utility model or exceed the scope defined by the claims, they should all fall within the protection scope of the utility model.

Claims

1. A differential oil circuit for a telescopic arm of an aerial work vehicle, comprising an electromagnetic reversing valve (1), a two-way balancing valve (2) and a telescopic oil cylinder (3), wherein a rodless chamber (3.1) and a rod chamber (3.2) are provided in the telescopic oil cylinder (3), characterized in that: It also includes a rodless chamber main path (4), a rod chamber main path (5), a rodless chamber bypass (6) and a rod chamber bypass (7), one end of the rodless chamber main path (4) is connected to the rodless chamber (3.1), one end of the rod chamber main path (5) is connected to the rod chamber (3.2), the other end of the rodless chamber main path (4) is connected to the other end of the rod chamber main path (5), and the other end of the rodless chamber main path (4) and the other end of the rod chamber main path (5) are both controlled by an electromagnetic reversing valve (1), a first balancing valve core (2.2) is installed on the rodless chamber main path (4), a second balancing valve core (2.5) is installed on the rod chamber main path (5), a first non-return valve (2.3) is installed on the rodless chamber bypass (6), a second non-return valve (2.4) is installed on the rod chamber bypass (7), and the second balancing valve core (2.5) is connected to the balancing valve control oil path (2.1).

2. The differential oil circuit for the telescopic arm of an aerial work vehicle according to claim 1, characterized in that: The rodless chamber main path (4) is provided with a first valve block oil outlet (C1) and a first valve block oil inlet (V1), and the first valve block oil outlet (C1) and the first valve block oil inlet (V1) are respectively connected to the two ends of the rodless chamber bypass (6); the rod chamber main path (5) is provided with a second valve block oil outlet (C2) and a second valve block oil inlet (V2), and the second valve block oil outlet (C2) and the second valve block oil inlet (V2) are respectively connected to the two ends of the rod chamber bypass (7).

3. The differential oil circuit for the telescopic arm of an aerial work vehicle according to claim 2, characterized in that: The first balancing valve core (2.2) is located between the first valve block oil outlet (C1) and the first valve block oil inlet (V1), and the second balancing valve core (2.5) is located between the second valve block oil outlet (C2) and the second valve block oil inlet (V2).

4. The differential oil circuit for the telescopic arm of an aerial work vehicle according to claim 2, characterized in that: One end of the balancing valve control oil circuit (2.1) is in communication with the first valve block oil inlet (V1), and the other end of the balancing valve control oil circuit (2.1) is in communication with the second balancing valve core (2.5).

5. The differential oil circuit for the telescopic arm of an aerial work vehicle according to claim 1, characterized in that: The electromagnetic reversing valve (1) is provided with a first oil outlet (A), a second oil outlet (B), an oil inlet (P) and an oil return port (T); the other end of the rodless chamber main path (4) and the other end of the rod chamber main path (5) are respectively connected to the first oil outlet (A) and the second oil outlet (B).

6. The differential oil circuit for the telescopic arm of an aerial work vehicle according to claim 1, characterized in that: The electromagnetic reversing valve (1) is provided with a first electromagnet (E) and a second electromagnet (F).

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