Valve block of tensioning oil pump and hydraulic system

Abstract

The utility model discloses a valve block of a tensioning oil pump and a hydraulic system. The valve block comprises a three-position four-way reversing valve, a one-way valve and a stop valve. One end of the three-position four-way reversing valve is respectively provided with a first oil way and a second oil way which are used for connecting an oil pump and an oil cylinder, and the other end of the three-position four-way reversing valve is respectively provided with a third oil way and a fourth oil way which are used for connecting a rodless cavity and a rod cavity of the telescopic cylinder; the one-way valve is arranged on the third oil way, and the flow direction of the one-way valve points to the rodless cavity; a first branch used for being communicated with the oil cylinder is further arranged between the one-way valve and the rodless cavity, and the stop valve is arranged on the first branch. The fourth oil way is further provided with a second branch used for being communicated with the oil cylinder, and the second branch is provided with a first overflow valve. According to the valve block of the tensioning oil pump and the hydraulic system, the first overflow valve is additionally arranged in the oil return path in the cylinder stretching process, so that the oil path, the three-position four-way reversing valve and the like maintain safe oil pressure, and hydraulic elements and a telescopic cylinder are prevented from being damaged.

Description

Technical Field

[0001] The utility model relates to the technical field of prestressed tensioning hydraulic pressure, in particular to a valve block and a hydraulic system of a tensioning oil pump. Background Art

[0002] The traditional prestressed tensioning oil pump adopts a 500-type oil pump control valve block, which includes two sets of oil supply circuits, oil return circuits and oil pump motors. One set is connected to the rodless chamber of the telescopic cylinder, and the other set is connected to the rod chamber of the telescopic cylinder. Both sets of oil supply paths are for the oil cylinder to directly supply oil to the telescopic cylinder through the oil pump and the one-way valve in turn, and the oil return paths are directly connected to the oil cylinder through the stop valve. The operation steps are relatively cumbersome during the prestressed component tensioning process: when supplying oil to the rodless chamber, it is necessary to first tighten the oil circuit stop valve corresponding to the rodless chamber, open the stop valve corresponding to the rod chamber, open the oil pump motor, and slowly tighten the throttle valve of the oil supply circuit to deliver oil; turn off the motor when maintaining pressure; when returning oil, first tighten the stop valve corresponding to the rod chamber, unscrew the stop valve corresponding to the rodless chamber, turn on the motor, and slowly tighten the throttle valve of the return oil circuit to return oil. The oil pump valve block has the following deficiencies: when the oil circuit is switched, the stop valves of the two sets of oil circuits need to be manually operated at the same time. If the operator is negligent, a dangerous situation will occur in which the oil supply circuit and the oil return circuit are simultaneously pressurized with oil, causing the pressure in the rod chamber and the rodless chamber to rise sharply, resulting in the rear sealing plate and the clamping ring flying off.

[0003] At present, there have been some improvements to the above-mentioned defects. For example, Chinese patent CN116791601A discloses a separated stepless speed-regulating anchor cable tensioning device, including a hydraulic module and an electrical control module which are separately arranged. The electrical control module includes a control main board and a frequency converter, and the frequency converter is electrically connected to the control main board and the variable frequency motor. The hydraulic module includes a three-position four-way electromagnetic reversing valve electrically connected to the control main board, and the oil inlet of the three-position four-way electromagnetic reversing valve is connected to the output end of the oil pump, and the oil return port of the three-position four-way electromagnetic reversing valve is connected to the oil tank. The first working port and the second working port of the three-position four-way electromagnetic reversing valve are respectively connected to the two ends of the piston in the jack, and the input end of the oil pump is connected to the oil tank; it also includes a one-way valve and a relief valve, the input end of the one-way valve is connected to the input end of the relief valve and the output end of the oil pump, the output end of the one-way valve is connected to the three-position four-way electromagnetic reversing valve, and the output end of the relief valve is connected to the oil tank. The prior art uses an electrically controlled three-position four-way reversing valve to replace the two sets of oil supply and outlet oil circuits of the traditional tensioning system, and adds a relief valve at the output end of the oil pump to prevent the oil pump from over-pressure and damage to the tensioning device. However, there is a safety hazard of excessive oil pressure at the return oil end, and an electrical control module is used to control the three-position four-way electromagnetic reversing valve, variable frequency motor, etc., which is costly and has control delays. Utility Model Content

[0004] In view of the above problems, the utility model provides a valve block and a hydraulic system for a tensioning oil pump, aiming to solve the safety hazards of excessive oil pressure at the return oil end, high electrical control cost, control delay and other problems in the prior art.

[0005] The utility model adopts the following technical solutions to achieve the above purpose:

[0006] A valve block for a tensioning oil pump, used for connecting a telescopic cylinder and an oil cylinder with an oil pump, the valve block comprising a three-position four-way reversing valve, a one-way valve and a stop valve; one end of the three-position four-way reversing valve is respectively provided with a first oil circuit and a second oil circuit for connecting the oil pump and the oil cylinder, and the other end is respectively provided with a third oil circuit and a fourth oil circuit for connecting the rodless chamber and the rod chamber of the telescopic cylinder; the one-way valve is arranged on the third oil circuit, and the flow direction of the one-way valve points to the rodless chamber; a first branch for connecting the oil cylinder is also provided between the one-way valve and the rodless chamber, and the stop valve is arranged on the first branch; the fourth oil circuit is also provided with a second branch for connecting the oil cylinder, and a first overflow valve is provided on the second branch.

[0007] In the present technical scheme, during the tensioning process, that is, the oil cylinder supplies oil to the rodless chamber and the rod chamber returns oil to the oil cylinder, the stop valve is closed, the three-position four-way reversing valve is switched to the cylinder extension position, the first oil circuit is connected with the third oil circuit, the second oil circuit is connected with the fourth oil circuit, the first branch is blocked, and the oil pump supplies oil to the rodless chamber through the first oil circuit, the three-position four-way reversing valve, the third oil circuit (and the one-way valve), and the rod chamber returns oil to the oil cylinder through the fourth oil circuit, the three-position four-way reversing valve, and the second oil circuit. At this time, when the oil pressure exceeds the safety oil pressure, the first overflow valve automatically opens, and the hydraulic oil flows back directly without passing through the three-position four-way reversing valve To the oil cylinder; when the tensioning reaches a predetermined force value, the three-position four-way reversing valve switches to the middle position, and the hydraulic system maintains pressure; when the tensioning is completed, the oil cylinder supplies oil to the rod chamber and the rodless chamber returns oil to the oil cylinder, the stop valve is opened, the three-position four-way reversing valve switches to the cylinder retraction position, the first oil circuit is connected with the fourth oil circuit, the one-way valve blocks the connection between the second oil circuit and the third oil circuit, the third oil circuit is connected with the oil cylinder through the first branch, the oil pump supplies oil through the first oil circuit, the three-position four-way reversing valve, and the fourth oil circuit to the rod chamber, the rodless chamber returns oil through the third oil circuit and the first branch to the oil cylinder, and the oil pump is turned off after the cylinder retraction is completed. The technical solution adds a first overflow valve in the return oil circuit during the extension process of the cylinder, and sets a safety oil pressure. When the oil pressure exceeds the safety oil pressure (for example, the connecting station between the second oil circuit and the fourth oil circuit in the three-position four-way reversing valve is partially blocked), the first overflow valve automatically opens, and the hydraulic oil directly returns to the cylinder, so that the oil circuit, the three-position four-way reversing valve, etc. maintain a safe oil pressure, thereby preventing damage to the hydraulic components and the telescopic cylinder.

[0008] A further technical solution is that a second overflow valve is provided between the first oil circuit and the second oil circuit. In this technical solution, a second overflow valve is provided on the oil supply circuit. When the oil pressure exceeds the safety oil pressure, the second overflow valve automatically opens, and the hydraulic oil in the oil supply circuit flows back to the oil cylinder through the second overflow valve, thereby avoiding damage to the hydraulic components and the telescopic cylinder.

[0009] A further technical solution is that a throttle valve is provided between the first oil circuit and the second oil circuit. In this technical solution, the oil pressure of the oil supply is controlled by adjusting the throttle valve, thereby replacing the electrical control in the prior art, saving the tensioning cost, and there is no control delay.

[0010] A further technical solution is that the one-way valve is a hydraulically controlled one-way valve, and the control oil port of the hydraulically controlled one-way valve is connected to the fourth oil circuit. In this technical solution, by adopting a hydraulically controlled one-way valve, the oil return can be completed without closing the stop valve during the cylinder retraction process. During the oil return process of the cylinder retraction, the oil pressure of the fourth oil circuit is higher than the oil pressure of the third oil circuit, thereby opening the piston of the one-way valve, connecting the third oil circuit with the second oil circuit, and the hydraulic oil in the rodless chamber returns to the cylinder through the third oil circuit, the three-position four-way reversing valve, and the second oil circuit.

[0011] A further technical solution is that the three-position four-way reversing valve includes a wrench for adjusting its working position. In this technical solution, the working position of the three-position four-way reversing valve is switched by the wrench, which is convenient for manual operation and has no switching delay.

[0012] A hydraulic system comprises an oil cylinder, an oil pump, a telescopic cylinder and the above-mentioned valve block.

[0013] The beneficial effects of the utility model are:

[0014] The utility model provides a valve block and a hydraulic system of a tensioning oil pump, in which a first overflow valve is added to the oil return circuit during the cylinder extension process, and a safety oil pressure is set. When the oil pressure exceeds the safety oil pressure, the first overflow valve automatically opens, and the hydraulic oil directly returns to the oil cylinder, so that the oil circuit, the three-position four-way reversing valve, etc. maintain the safety oil pressure, thereby preventing damage to the hydraulic components and the telescopic cylinder; and the oil pressure of the oil supply is controlled by adjusting the throttle valve, thereby replacing the electrical control in the prior art, saving tensioning costs, and without control delay. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 The hydraulic principle diagram of the tensioning oil pump valve block of the utility model is shown in FIG.

[0016] In the figure:

[0017] 1. Oil cylinder; 2. Three-position four-way reversing valve; 3. One-way valve; 4. Stop valve; 51. First oil circuit; 52. Second oil circuit; 53. Third oil circuit; 54. Fourth oil circuit; 61. First branch; 62. Second branch; 71. First overflow valve; 72. Second overflow valve; 8. Throttle valve. DETAILED DESCRIPTION

[0018] The following is combined with Figure 1 The present invention is described in detail with specific implementation modes. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0019] like Figure 1 As shown, the present embodiment provides a valve block of a tensioning oil pump, which is used to connect the telescopic cylinder and the oil cylinder 1 with an oil pump, and the valve block includes a three-position four-way reversing valve 2, a one-way valve 3, and a stop valve 4; one end of the three-position four-way reversing valve 2 is respectively provided with a first oil circuit 51 and a second oil circuit 52 for connecting the oil pump and the oil cylinder 1, and the other end is respectively provided with a third oil circuit 53 and a fourth oil circuit 54 for connecting the rodless chamber and the rod chamber of the telescopic cylinder; the one-way valve 3 is arranged on the third oil circuit 53, and the flow direction of the one-way valve 3 points to the rodless chamber; a first branch 61 for connecting the oil cylinder 1 is also provided between the one-way valve 3 and the rodless chamber, and the stop valve 4 is arranged on the first branch 61; the fourth oil circuit 54 is also provided with a second branch 62 for connecting the oil cylinder 1, and a first overflow valve 71 is provided on the second branch 62.

[0020] Specifically, the one-way valve 3 in the present embodiment is a mechanical one-way valve, which only includes an input end connected to the three-position four-way reversing valve 2 and an output end connected to the rodless chamber; its working principle is: in the tensioning condition (the piston rod needs to extend the telescopic cylinder for tensioning), that is, the cylinder supplies oil to the rodless chamber and the rod chamber returns oil to the cylinder, the stop valve 4 is closed, the three-position four-way reversing valve 2 works in the right position (cylinder extension position), the first oil circuit 51 is connected with the third oil circuit 53, the second oil circuit 52 is connected with the fourth oil circuit 54, the first branch 61 is blocked, the oil pump supplies oil to the rodless chamber through the first oil circuit 51, the three-position four-way reversing valve 2, the third oil circuit 53 (and the one-way valve 3), the rod chamber returns oil through the fourth oil circuit 54, the three-position four-way reversing valve 2, and the second oil circuit 52 back to the cylinder. At this time, when the oil pressure exceeds the safety oil pressure, the first overflow valve 71 opens automatically, and the hydraulic oil in the rod chamber flows back to the cylinder directly through the second branch 62 without passing through the three-position four-way reversing valve 2; when the tensioning reaches the predetermined force value, the three-position four-way reversing valve 2 switches to the middle position, and the hydraulic system maintains pressure; when the tensioning is completed, that is, the cylinder 1 supplies oil to the rod chamber and the rodless chamber returns oil to the cylinder 1, the stop valve 4 is opened, the three-position four-way reversing valve 2 switches to the left position (cylinder retraction position), the first oil circuit 51 is connected with the fourth oil circuit 54, the one-way valve 3 blocks the connection between the second oil circuit 52 and the third oil circuit 53, the third oil circuit 53 is connected with the cylinder 1 through the first branch 61, the oil pump supplies oil to the rod chamber through the first oil circuit 51, the three-position four-way reversing valve 2, and the fourth oil circuit 54, the rodless chamber returns oil through the third oil circuit 53 and the first branch 61 to the cylinder 1, and the oil pump is closed after the cylinder retraction is completed. The valve body structure of this embodiment adds a first overflow valve 71 in the return oil circuit of the extension cylinder (the oil inlet circuit of the retraction cylinder) to set a safety oil pressure. When the oil pressure exceeds the safety oil pressure (for example, the connecting station between the second oil circuit 52 and the fourth oil circuit 54 in the three-position four-way reversing valve 2 at the extension cylinder station is partially blocked), the first overflow valve 71 automatically opens, and the hydraulic oil directly returns to the cylinder 1, so that the oil circuit, the three-position four-way reversing valve 2, etc. maintain a safe oil pressure to prevent damage to the hydraulic components and the telescopic cylinder.

[0021] Another embodiment, on the basis of the above embodiment, in order to further improve the safety of the valve body structure and the hydraulic system, a second overflow valve 72 is arranged between the first oil circuit 51 and the second oil circuit 52, wherein the input end of the second overflow valve 72 is connected to the first oil circuit 51, and the output end is connected to the second oil circuit 52, and the second overflow valve 72 is arranged on the oil supply circuit. When the oil pressure exceeds the safety oil pressure, the second overflow valve 72 automatically opens, and the hydraulic oil in the oil supply circuit directly flows back to the cylinder through the second overflow valve 72 and the second oil circuit 52, so as to avoid damage to the hydraulic components and the telescopic cylinder.

[0022] Another embodiment, on the basis of the above embodiment, in order to save tensioning costs and reduce the complexity of the tensioning system, a throttle valve 8 is provided between the first oil circuit 51 and the second oil circuit 52, and both ends of the throttle valve 8 are connected to the first oil circuit 51 and the second oil circuit 52 through pipelines respectively. Part of the hydraulic oil in the first oil circuit 51 can flow back to the cylinder 1 through the throttle valve 8 and the second oil circuit 52, and the oil pressure of the oil supply can be controlled by adjusting the opening and closing degree of the throttle valve 8, thereby replacing the electrical control in the prior art, saving tensioning costs, and there is no control delay.

[0023] Another embodiment is different from the above embodiment in that the one-way valve 3 is a hydraulically controlled one-way valve, and the control oil port of the hydraulically controlled one-way valve is connected to the fourth oil circuit 54. By adopting the hydraulically controlled one-way valve, the oil return can be completed without closing the stop valve 4 during the cylinder retraction process. During the oil return process of the cylinder retraction, the oil pressure of the fourth oil circuit 54 is higher than the oil pressure of the third oil circuit 54, thereby opening the piston of the hydraulically controlled one-way valve, so that the third oil circuit 53 is connected to the second oil circuit 52, and the hydraulic oil in the rodless chamber returns to the cylinder 1 through the third oil circuit 53, the three-position four-way reversing valve 2, and the second oil circuit 52.

[0024] In another embodiment, in order to facilitate manual operation and further reduce control delay, the three-position four-way directional valve 2 includes a wrench for adjusting its working position, and the working position of the three-position four-way directional valve 2 is switched by the wrench.

[0025] Another embodiment, based on the above embodiment, provides a hydraulic system, including an oil cylinder 1, an oil pump, a telescopic cylinder, and the valve block described in the above embodiment.

[0026] The utility model provides a valve block and a hydraulic system of a tensioning oil pump, in which a first overflow valve 71 is added to the oil return circuit during the cylinder extension process, and a safety oil pressure is set. When the oil pressure exceeds the safety oil pressure, the first overflow valve 71 automatically opens, and the hydraulic oil directly returns to the oil cylinder 1, so that the oil circuit, the three-position four-way reversing valve 2, etc. maintain the safety oil pressure to prevent damage to the hydraulic components and the telescopic cylinder; and the oil pressure of the oil supply is controlled by adjusting the throttle valve 8, thereby replacing the electrical control in the prior art, saving tensioning costs, and there is no control delay.

Claims

1. A valve block for a tensioning oil pump, used to connect a telescopic cylinder and an oil cylinder with an oil pump, characterized in that: The valve block includes a three-position four-way reversing valve, a one-way valve, and a stop valve; One end of the three-position four-way reversing valve is respectively provided with a first oil circuit and a second oil circuit for connecting the oil pump and the oil cylinder, and the other end is respectively provided with a third oil circuit and a fourth oil circuit for connecting the rodless chamber and the rod chamber of the telescopic cylinder; The one-way valve is arranged on the third oil circuit, and the flow direction of the one-way valve points to the rodless chamber; a first branch for connecting the oil cylinder is also arranged between the one-way valve and the rodless chamber, and the stop valve is arranged on the first branch; The fourth oil circuit is further provided with a second branch for communicating with the oil cylinder, and the second branch is provided with a first overflow valve.

2. A valve block for a tension oil pump according to claim 1, characterized in that: A second overflow valve is provided between the first oil circuit and the second oil circuit.

3. The valve block of a tension oil pump according to claim 1, characterized in that: A throttle valve is provided between the first oil circuit and the second oil circuit.

4. The valve block of a tension oil pump according to claim 1, characterized in that: The one-way valve is a hydraulically controlled one-way valve, and a control oil port of the hydraulically controlled one-way valve is connected to the fourth oil circuit.

5. The valve block of a tension oil pump according to claim 1, characterized in that: The three-position four-way reversing valve comprises a wrench for adjusting its working position.

6. A hydraulic system, characterized in that: It comprises an oil cylinder, an oil pump, a telescopic cylinder, and a valve block as described in any one of claims 1 to 5.

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