Integral inlet valve group for vertical or oblique injection

Abstract

The utility model provides a whole inlet valve group for vertical or oblique injection, which comprises a hydraulic valve block, an electromagnetic reversing valve, a one-way back pressure valve and a hydraulic control one-way valve are arranged in the hydraulic valve block, one outlet of the electromagnetic reversing valve is sequentially communicated with the one-way valve of the one-way back pressure valve and the hydraulic control one-way valve, and the other outlet of the electromagnetic reversing valve is communicated with the hydraulic control one-way valve. The hydraulic control one-way valve is communicated with a port A of the hydraulic valve block and the two-position two-way electromagnetic valve, the other outlet of the electromagnetic reversing valve is communicated with the two-position two-way electromagnetic valve, and the two-position two-way electromagnetic valve is communicated with a port B of the hydraulic valve block. According to the utility model, oil in the large cavity of the hydraulic oil cylinder is prevented from leaking from the overflow valve in the one-way back pressure valve when the whole-feeding valve group stops for a long time, the sliding of the injection unit caused by the movement of the oil cylinder under the action of gravity is avoided, and the situation that the injection unit cannot work normally or even is damaged during alarming is effectively prevented.

Description

Technical Field

[0001] This utility model relates to a hydraulic valve assembly for vertical or oblique injection in injection molding machines. Background Technology

[0002] like Figure 1 As shown, this is a traditional injection valve assembly. The P port of the hydraulic valve block 2 is connected to the oil source of the hydraulic pump. When the solenoid directional valve 6 is pushed to the right, the hydraulic oil flows through the one-way valve of the one-way back pressure valve 5 from port A into the large chamber of the hydraulic cylinder 1. The oil in the small chamber returns to the oil tank through the two-position two-way solenoid valve 3 and the solenoid directional valve 6, causing the entire injection unit to rise. When the solenoid directional valve 6 is pushed to the left, connecting its P port to its corresponding outlet, the hydraulic oil flows through the two-position two-way solenoid valve 3 from port B into the small chamber of the hydraulic cylinder 1. The oil in the large chamber returns to the oil tank through the relief valve of the one-way back pressure valve 5 and the solenoid directional valve, causing the entire injection unit to descend. The function of the two-position two-way solenoid valve 3 is to maintain contact force when closed and to relieve load when open. The function of the one-way back pressure valve 5 is to ensure that the injection unit has no back pressure when rising and has back pressure when descending, preventing damage to components due to excessive descent speed.

[0003] The one-way back pressure valve in the above-mentioned injection valve assembly has a certain leakage. When the injection unit compresses the hydraulic cylinder due to its own weight, the large chamber of the hydraulic cylinder is loaded. If this is done for a long time, the hydraulic oil will leak from the relief valve in the one-way back pressure valve, causing the hydraulic cylinder to move, the injection unit to slide down, triggering an alarm and preventing it from working properly. In severe cases, it may damage the components. Summary of the Invention

[0004] The technical problem to be solved by this utility model is: how to prevent the injection unit from sliding down due to oil leakage from the inlet valve group.

[0005] To address the aforementioned problems, this utility model provides a pre-injection valve assembly for vertical or oblique injection, comprising a hydraulic valve block. The P port of the hydraulic valve block is connected to an oil source via a hydraulic pump. The hydraulic valve block contains an electromagnetic directional valve, a one-way back pressure valve, and a hydraulically controlled one-way valve. The P port of the hydraulic valve block is connected to the P port of the electromagnetic directional valve. The T port of the hydraulic valve block is connected to the T port of the electromagnetic directional valve, the overflow valve of the one-way back pressure valve, and the outlet of the safety valve. One outlet of the electromagnetic directional valve is sequentially connected to the one-way valve of the one-way back pressure valve and the hydraulically controlled one-way valve. The hydraulically controlled one-way valve is connected to the A port of the hydraulic valve block and a two-position two-way electromagnetic valve. The other outlet of the electromagnetic directional valve is connected to the two-position two-way electromagnetic valve. The two-position two-way electromagnetic valve is connected to the B port of the hydraulic valve block. The A port of the hydraulic valve block is connected to the large chamber of the hydraulic cylinder, and the B port is connected to the small chamber of the hydraulic cylinder.

[0006] Preferably, the T port of the hydraulic valve block is also connected to the B port of the hydraulic valve block through a safety valve.

[0007] Preferably, when the P port of the solenoid directional valve is connected to its corresponding outlet, the hydraulic oil enters the large chamber of the hydraulic cylinder through the check valve of the one-way back pressure valve, the hydraulically controlled check valve, and the A port. The oil in the small chamber returns to the oil tank through the two-position two-way solenoid valve, the hydraulically controlled check valve, the one-way back pressure valve, and the solenoid directional valve, causing the entire injection unit to rise. When the solenoid directional valve is connected to another outlet, the hydraulic oil enters the small chamber of the hydraulic cylinder through the solenoid directional valve, the one-way back pressure valve, the hydraulically controlled check valve, and the two-position two-way solenoid valve. At this time, the hydraulically controlled check valve is open under the pressure of the control oil. The oil in the large chamber returns to the oil tank through the hydraulically controlled check valve, the relief valve of the one-way back pressure valve, and the solenoid directional valve, causing the entire injection unit to descend.

[0008] This invention prevents the oil in the large chamber of the hydraulic cylinder from leaking through the overflow valve in the one-way back pressure valve when the machine is shut down for a long time. It also prevents the injection unit from sliding due to the movement of the cylinder under gravity, effectively preventing the components from failing to work properly or even being damaged when an alarm is triggered. Attached Figure Description

[0009] Figure 1 This is a schematic diagram of a traditional inlet valve assembly;

[0010] Figure 2 A schematic diagram of the infeed valve assembly for vertical or oblique injection provided by this utility model. Detailed Implementation

[0011] To make this utility model more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings.

[0012] Example

[0013] A pre-injection valve assembly for vertical or oblique injection includes a hydraulic valve block 2. The P port of the hydraulic valve block 2 is connected to an oil source via a hydraulic pump. The hydraulic valve block 2 is characterized by having an electromagnetic directional valve 6, a one-way back pressure valve 5, and a hydraulically controlled one-way valve 4 within it. The P port of the hydraulic valve block 2 is connected to the P port of the electromagnetic directional valve 6, and the T port of the hydraulic valve block 2 is connected to the T port of the electromagnetic directional valve 6, the relief valve of the one-way back pressure valve 5, and a safety valve 7. When the injection unit encounters external force and the pressure in the small chamber of the cylinder increases, the pressure can be released through the safety valve 7 to protect the system pressure. One outlet of the solenoid directional valve 6 is sequentially connected to the check valve of the one-way back pressure valve 5 and the hydraulically controlled check valve 4. The hydraulically controlled check valve 4 is connected to port A of the hydraulic valve block 2 and the two-position two-way solenoid valve 3. The other outlet of the solenoid directional valve 6 is connected to the two-position two-way solenoid valve 3, which is connected to port B of the hydraulic valve block 2. Port A of the hydraulic valve block 2 is connected to the large chamber of the hydraulic cylinder 1, and port B is connected to the small chamber of the hydraulic cylinder 1. A pressure gauge 8 is installed on port B of the hydraulic valve block 2 to display the pressure at port B in real time.

[0014] When the solenoid directional valve 6 is pushed to the left so that its P port connects with its corresponding outlet, the hydraulic oil enters the large chamber of the hydraulic cylinder 1 through the one-way valve of the one-way back pressure valve 5, the hydraulically controlled one-way valve 4, and the A port. The oil in the small chamber returns to the oil tank through the two-position two-way solenoid valve 3, the hydraulically controlled one-way valve 4, the one-way back pressure valve 5, and the solenoid directional valve 6, and the entire injection unit rises. When the solenoid directional valve 6 is pushed to the right, the hydraulic oil enters the small chamber of the hydraulic cylinder 1 through the solenoid directional valve 6, the one-way back pressure valve 5, the hydraulically controlled one-way valve 4, and the two-position two-way solenoid valve 3. At this time, the hydraulically controlled one-way valve 4 is in the open state under the pressure of the control oil. The oil in the large chamber returns to the oil tank through the hydraulically controlled one-way valve 4, the relief valve of the one-way back pressure valve 5, and the solenoid directional valve 6, and the entire injection unit descends.

[0015] The function of the two-position two-way solenoid valve 3 is to maintain contact force when closed and to relieve load when open.

[0016] The function of the one-way back pressure valve 5 is to prevent the injection unit from having back pressure when it rises and to have back pressure when it falls, so as to prevent the components from being damaged by excessive speed when it falls.

[0017] The function of the hydraulic check valve 4 is that when the machine is stationary, since there is no pressure in the control oil, the hydraulic check valve is closed, and the oil in the large chamber of the hydraulic cylinder 1 cannot return to the oil tank, so the injection unit will not slide down.

Claims

1. A feed valve assembly for vertical or oblique injection, comprising a hydraulic valve block (2), wherein the P port of the hydraulic valve block (2) is connected to an oil source, characterized in that, The hydraulic valve block (2) is equipped with an electromagnetic directional valve (6), a one-way back pressure valve (5), and a hydraulically controlled one-way valve (4). The P port of the hydraulic valve block (2) is connected to the P port of the electromagnetic directional valve (6), and the T port of the hydraulic valve block (2) is connected to the T port of the electromagnetic directional valve (6) and the overflow valve of the one-way back pressure valve (5). One of the outlets of the electromagnetic directional valve (6) is connected to the one-way valve of the one-way back pressure valve (5) and the hydraulically controlled one-way valve (4) in sequence. The hydraulically controlled one-way valve (4) is connected to the A port of the hydraulic valve block (2) and the two-position two-way electromagnetic valve (3). The other outlet of the electromagnetic directional valve (6) is connected to the two-position two-way electromagnetic valve (3). The two-position two-way electromagnetic valve (3) is connected to the B port of the hydraulic valve block (2). The A port of the hydraulic valve block (2) is connected to the large cavity of the hydraulic cylinder (1), and the B port is connected to the small cavity of the hydraulic cylinder (1).

2. The infeed valve assembly for vertical or oblique injection as described in claim 1, characterized in that, The T port of the hydraulic valve block (2) is also connected to the B port of the hydraulic valve block (2) through a safety valve (7).

3. The infeed valve assembly for vertical or oblique injection as described in claim 1, characterized in that, When the P port of the solenoid directional valve (6) is connected to its corresponding outlet, the hydraulic oil enters the large chamber of the hydraulic cylinder (1) through the check valve of the one-way back pressure valve (5), the hydraulic control check valve (4), and the A port. The oil in the small chamber returns to the oil tank through the two-position two-way solenoid valve (3), the hydraulic control check valve (4), the one-way back pressure valve (5), and the solenoid directional valve (6), and the entire injection unit rises. When the T port of the solenoid directional valve (6) is connected to the outlet, the hydraulic oil enters the small chamber of the hydraulic cylinder (1) through the solenoid directional valve (6), the one-way back pressure valve (5), the hydraulic control check valve (4), and the two-position two-way solenoid valve (3). At this time, the hydraulic control check valve (4) is in the open state under the pressure of the control oil. The oil in the large chamber returns to the oil tank through the hydraulic control check valve (4), the overflow valve of the one-way back pressure valve (5), and the solenoid directional valve (6), and the entire injection unit descends.

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