Novel hydraulic control system of cubic press

Abstract

The utility model discloses a novel hydraulic control system of a cubic press. The novel hydraulic control system comprises a low-pressure control part, a high-pressure control part and a coaxial hydraulic motor and pump set part. According to the system, a coaxial hydraulic motor is connected in series or in bypass parallel to a low-pressure control part, so that the advancing and liquid filling step control of six hinge beam oil cylinders is realized, and the synchronous advancing from the advancing of three cylinders to the hammer stopping position, the starting synchronism of the liquid filling step and the accurate control of the liquid filling displacement in the liquid filling process are realized; therefore, the cubic press has excellent synchronism.

Description

Technical Field

[0001] The utility model belongs to the field of diamond synthesis equipment, and in particular relates to a novel hydraulic control system for a six-sided top press. Background Art

[0002] The six-sided top synthesis press is a superhard material synthesis equipment commonly used in my country's superhard material industry. As an ultra-high pressure hydraulic equipment, hydraulic control is an important component. It is mainly composed of a low-pressure control part, a high-pressure control part and a pump group. Over the years, the ultra-high pressure and pressure relief parts of the hydraulic system have not changed except for the improvement of the ultra-high pressure source from a single-stroke supercharger to a two-stroke reciprocating supercharger and an ultra-high pressure oil pump and pressure relief components.

[0003] The low-pressure control part is to connect the ultra-high pressure hydraulic control check valve, two-position four-way solenoid reversing valve and throttle valve in series in the rear chambers of the six ultra-high pressure oil cylinders. The lower ends of the six throttle valves are connected in parallel to the A port of the first three-position four-way solenoid reversing valve, while the front chambers of the six hinged beam oil cylinders are connected in parallel to the balance valve and then connected to the B port of the three-position four-way solenoid reversing valve; the six ultra-high pressure hydraulic control check valves and ultra-high pressure hydraulic control seven-way valves are used as the boundary partitions between the low-pressure part and the ultra-high pressure and pressure relief parts. The electromagnet at the right end of the three-position four-way solenoid reversing valve is energized to realize the forward movement of the oil cylinder, and the electromagnet at the left end is energized to realize the return movement of the oil cylinder. When the six hinged beam oil cylinders return, the two-position four-way solenoid reversing valve that drives the ultra-high pressure hydraulic control check valve is energized, and the hydraulic oil in the rear chamber of the oil cylinder returns to the oil tank from the A port of the first two-position four-way solenoid reversing valve to the T port through the ultra-high pressure hydraulic control check valve. The control function of the low-pressure control part is to control the single-cylinder forward and backward movement of the six hinge beam cylinders, and to realize the "three-cylinder forward" step of the three movable hinge beam cylinders from the return position to the hammer stop position, which is realized by controlling the opening of the two-position four-way electromagnetic reversing valve of each cylinder. The throttle valve has the function of adjusting the speed of the corresponding hinge beam cylinder; another control function of the low-pressure control part is to realize that at the beginning of the synthesis, the six hinge beam cylinders start to move forward synchronously from the displacement "0" position of the hammer stop position with a given filling pressure. This step is the "filling" step. Generally, the hydraulic flow of the throttle valve corresponding to each cylinder is adjusted to realize the synchronous filling of the displacement of the six hinge beam cylinders. The filling pressure is generally 6-10MPa. The six-sided top hydraulic system currently used in the industry is shown in the attached Figure 1 .

[0004] At present, the shortcomings of the hydraulic system of the six-sided top press in controlling the "filling" step are: the cylinder speed is adjusted by the throttle valve. Due to the different spatial positions of the six hinged beam cylinders, the different damping sizes of the pistons of each cylinder, the different lengths of the pipelines leading to each cylinder from the hydraulic station, the different spatial positions of the hydraulic cylinders causing different gravity, and the change in hydraulic oil viscosity caused by the oil temperature and many other factors, when the single cylinder and three cylinders are moving forward, the cylinder forward speed error is large, especially at the beginning of the "filling" step, the six cylinders are not started at the same time, which will cause a starting error of up to 1 second; at the end of filling, the displacement stroke error of the six hinged beam cylinders will generally reach about 2mm, and the six-cylinder displacement synchronization in a strict sense cannot be achieved. Utility Model Content

[0005] In order to address the deficiencies in the prior art, the utility model aims to provide a novel hydraulic control system for a six-sided top press. The system utilizes a coaxial hydraulic motor to perform constant-volume oil supply and synchronous liquid filling control on six hinged beam cylinders, thereby realizing the forward synchronization of the three cylinders, the starting synchronization of the liquid filling step, and precise control of the filling displacement during the liquid filling process, so that the six-sided top press has excellent synchronization.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is:

[0007] A novel hydraulic control system for a six-sided top press comprises a low-pressure control part, a high-pressure control part and a pump group part, wherein the low-pressure control part comprises an ultra-high-pressure hydraulically controlled one-way valve, a first two-position four-way reversing valve and a throttle valve respectively connected in series with the rear chambers of six hinged beam oil cylinders; the T port of the first two-position four-way reversing valve is connected to the return oil system pipeline; the six throttle valves are connected in parallel and then connected to the A port of the three-position four-way reversing valve, and the P port of the three-position four-way reversing valve is connected to the system pressure of the pump group; it also comprises a coaxial hydraulic motor, which comprises six coaxially connected hydraulic motors, and the six hydraulic motors are connected in series between the first two-position four-way reversing valve and the three-position four-way reversing valve instead of the throttle valve, or are connected in parallel with the corresponding throttle valve and the three-position four-way reversing valve bypass; the front chambers of the six hinged beam oil cylinders are respectively connected in series with the corresponding second two-position four-way reversing valve and the balancing valve, and then connected together and then connected to the B port of the three-position four-way reversing valve.

[0008] Furthermore, when the coaxial hydraulic motors are connected in series instead of the throttle valves, the oil outlets of the six hydraulic motors are connected to the corresponding P ports of the first two-position four-way reversing valve, and the oil inlets are connected to the A port of the three-position four-way reversing valve.

[0009] Furthermore, when the coaxial hydraulic motors are bypassed in parallel, a corresponding first check valve is also connected in series between the throttle valve and the first two-position four-way reversing valve; the oil outlets of the six hydraulic motors are respectively connected in series with the corresponding second check valves and then connected between the corresponding first two-position four-way reversing valve P port and the first check valve, and the oil inlet is connected to the A port of the third two-position four-way reversing valve, and the P port of the third two-position four-way reversing valve is connected to the pump group system pressure.

[0010] Preferably, each hydraulic motor oil outlet cavity of the coaxial hydraulic motor is also provided with a pressure regulating relief valve and a third one-way valve.

[0011] Preferably, after the oil inlet passages of the six hydraulic motors of the coaxial hydraulic motor are connected, there is at least one common total oil inlet, while the oil outlets thereof are independent of each other.

[0012] Preferably, the second two-position four-way reversing valve is in a normally open state when not energized.

[0013] Compared with the prior art, the utility model has the following beneficial effects:

[0014] 1. In the new type of hydraulic control system of the six-sided top press proposed by the utility model, a coaxial hydraulic motor is added to the low-pressure control circuit, and six oil motors with the same displacement and coaxial connection are adopted, so that the coaxial hydraulic motor is forced to output hydraulic oil with equal pressure and flow, and the six hinge beam cylinders are supplied with oil and filled with liquid in a constant volume manner. When the overload of the six hinge beam cylinders is within 15%, the coaxial hydraulic motor can achieve a synchronous displacement error within 3%. In this way, the six hinge beam cylinders are not affected by the influence of the self-gravity of different hydraulic cylinder damping and different piston positions, the length and number of elbows of the hydraulic pipeline from the hydraulic station to the hinge beam cylinder, and the viscosity change caused by the oil temperature, etc. on the influence of the cylinder forward movement and liquid filling synchronization.

[0015] 2. The utility model connects normally open second two-position four-way reversing valves and balance valves in series in the front chambers of the six hinged beam oil cylinders. When the filling step starts, the six second two-position four-way reversing valves are first energized to close the front chamber oil circuit. When the rear chambers of the six hinged beam oil cylinders first build up a certain pressure, the power is cut off to make the six second two-position four-way reversing valves open. In this way, under the condition that the rear chambers of the six hinged beam oil cylinders have a certain pressure, the six hinged beam oil cylinders can improve the synchronization of filling and starting, and the respective balance valves can also fine-tune the filling and starting pressure of the six cylinders, eliminating the factors that affect the synchronization of filling and starting, such as the tightness of the seals of some hinged beam oil cylinders and the gravity deviation of the piston position, so as to achieve the highest synchronization of filling and starting. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of a six-sided top hydraulic system of the prior art;

[0017] Figure 2 This is a schematic diagram of the structure of the oil inlet and outlet of the coaxial hydraulic motor of the utility model;

[0018] Figure 3 It is a structural schematic diagram of the hydraulic control system of Example 1;

[0019] Figure 4 It is a structural schematic diagram of the hydraulic control system of Example 2. DETAILED DESCRIPTION

[0020] The principles and features of the present invention are described below in conjunction with the accompanying drawings. The examples given are only used to explain the present invention and are not intended to limit the scope of use of the present invention.

[0021] Embodiment 1:

[0022] like Figure 3 As shown, the utility model proposes a novel hydraulic control system for a six-sided top press, including a low-pressure control part, a high-pressure control part, a pump group part and a coaxial hydraulic motor 6, and an ultra-high-pressure hydraulic control one-way valve 3 and an ultra-high-pressure hydraulic control seven-way valve 8 of the high-pressure control part are used as the boundary isolation between the low-pressure and high-pressure parts. The low-pressure control part includes an ultra-high-pressure hydraulic control one-way valve 3 and a first two-position four-way reversing valve 11 respectively connected in series with the rear chambers of the six hinged beam oil cylinders, and the coaxial hydraulic motor 6 includes six coaxially connected hydraulic motors 61. The oil outlet 63 of the six hydraulic motors 61 is connected to the P port of the first two-position four-way reversing valve 11, and the oil inlet 62 thereof is connected to the A port of the three-position four-way reversing valve 7, and the P port of the three-position four-way reversing valve 7 is connected to the pump group system pressure. The corresponding second two-position four-way reversing valve 12 and the balance valve 2 are respectively connected in series in the front chambers of the six hinged beam oil cylinders, and the upper ends of the six balance valves 2 are connected in parallel and then connected to the B port of the three-position four-way electromagnetic reversing valve. The connection is a series connection between the coaxial hydraulic motor 6 and the low-pressure control part.

[0023] Specifically, Figure 2 As shown, in this embodiment, the coaxial hydraulic motor 6 is an integral structure, including six coaxially connected hydraulic gear motors. After the oil inlet passages of the six hydraulic motors 61 are connected, there is at least one common total oil inlet 62, and their oil outlets 63 are independent. The hydraulic motor 61 has a small size, low cost, and is easy to arrange on the hydraulic station.

[0024] The specific selection of the coaxial hydraulic motor 6 is: a hydraulic motor 61 with a single-piece flow rate of 40ml, a working pressure of 20MPa, and a speed range of 800-1800rpm can be selected. Taking the hydraulic system adapted to the φ850 cylinder diameter six-sided top press as an example, the cylinder diameter and piston area of ​​the φ850 hinge beam oil cylinder are 56.7dm 2 The idle stroke of the cylinder is about 70mm, and the required oil supply is 37.6L; the maximum filling displacement is about 5mm, and the required filling oil volume is 2.835L, and the filling time is 3-5 seconds.

[0025] The specific parameters of the coaxial hydraulic motor 6 are as follows: the displacement of a single oil motor is 40ml / r, the rated pressure is 20MPa, the maximum pressure is 25MPa, and the synchronous speed range is 800-1600r / min. Generally, in the "single cylinder forward" and "three cylinders forward", the single hydraulic motor 61 corresponding to each hinge beam cylinder needs to supply 37.6L of oil and needs to rotate 940r. According to the speed of the coaxial hydraulic motor 6 at 1400r / min, the cylinder stroke time is 35s, which meets the time requirement for the cylinder forward; in the "filling" step, the single hydraulic motor 61 of the coaxial hydraulic motor 6 needs to rotate 75 times according to the 3L hydraulic oil volume, and also according to the speed of 1400r / min, it takes 3 seconds to meet the filling time requirement of the six cylinders.

[0026] The coaxial hydraulic motor 6 realizes the control process of "single cylinder forward", "three cylinders forward" and "oil cylinder return": the right end of the three-position four-way reversing valve 7 is energized, and the valve position is turned to the oil cylinder forward position for oil supply; the first and second position four-way reversing valves 11 of the circuit that needs to be controlled are energized, and the hydraulic oil is supplied to the hinge beam oil cylinder through the coaxial hydraulic motor 6 through the P port and A port of the first and second position four-way electromagnetic reversing valve; and the oil cylinder that does not need to be moved, because the corresponding first and second position four-way electromagnetic reversing valve is not energized, its P port and B port are connected, and the hydraulic oil passing through the hydraulic motor 61 returns to the oil tank through the connection of the P port and the B port, and the corresponding oil cylinder does not move. When the oil cylinder needs to return, the electromagnet at the left end of the three-position four-way reversing valve 7 is energized, and the hydraulic oil is from the P port to the B port of the three-position four-way reversing valve 7 to the oil cylinder front cavity circuit, and the piston retreats to make the hydraulic oil return to the oil tank through the ultra-high pressure hydraulic control check valve 3 and the A port to the T port of the first and second position four-way reversing valve 11.

[0027] The filling process of the coaxial hydraulic motor 6: the electromagnet at the right end of the three-position four-way reversing valve 7 is energized, and the hydraulic oil output from the oil outlet 63 of the six hydraulic motors 61 of the coaxial hydraulic motor 6 passes through the first and second-position four-way reversing valves 11 and the ultra-high-pressure hydraulic-controlled one-way valve 3 to the hinged beam cylinder to push the piston upward. Since the coaxial hydraulic motor 6 is a six-piece oil motor with the same displacement and is coaxially connected, the six coaxially connected oil motors are forced to output hydraulic oil with equal pressure and flow, and supply oil and filling to the six hinged beam cylinders in a constant volume manner; when the overload of the six hinged beam cylinders is within 15%, the coaxial hydraulic motor 6 can achieve a synchronous displacement error within 3%, thereby realizing constant volume filling.

[0028] In order to further improve the synchronization of the six hinged beam oil cylinders during the filling and starting, the normally open second two-position four-way reversing valve 12 and the balance valve 2 are respectively connected in series in the front chambers of the six hinged beam oil cylinders, and the second two-position four-way reversing valve 12 is normally open when not energized. At the beginning of the filling process, the second two-position four-way reversing valve 12 is first energized to close the front chamber oil circuit, and when the rear chambers of the six hinged beam oil cylinders first build up a certain pressure, the six second two-position four-way reversing valves 12 are then de-energized, and the front chamber passage is opened. Under the condition that the rear chambers of the six hinged beam oil cylinders have a certain pressure, the six hinged beam oil cylinders can further improve the synchronization during the filling and starting, and the respective balance valves 2 can also fine-tune the filling and starting pressure of the six cylinders, eliminating the factors that affect the synchronization of the filling and starting, such as the tightness of the seals of some hinged beam oil cylinders and the gravity deviation of the piston position, so as to achieve the highest synchronization of the filling and starting.

[0029] In addition, the oil outlet 63 of each hydraulic motor 61 of the coaxial hydraulic motor 6 is also provided with a corresponding overflow valve 4 and a third one-way valve 53, which can fine-tune its output pressure and flow, fine-tune the cylinder speed and displacement more delicately, and further improve the synchronization of liquid filling.

[0030] In summary, this system achieves the synchronization of the three cylinders' forward movement, the synchronization of the start of the filling process, and the precise control of the filling displacement during the filling process, making the six-sided top press machine have excellent synchronization. The filling start error of the six hinged beam cylinder filling process can be less than 0.2 seconds, and the displacement error of the six hinged beam cylinders is less than 0.3mm after the filling is completed.

[0031] This embodiment has a simple structure and is the simplest implementation method of the utility model.

[0032] Embodiment 2:

[0033] like Figure 4 As shown, the difference from the above embodiment is that in this embodiment, the rear chamber of each hinge beam oil cylinder is connected in series with the ultra-high pressure hydraulic control check valve 3 and the first two-position four-way electromagnetic reversing valve, the corresponding first check valve 51 is connected in series between the first two-position four-way reversing valve 11 and the throttle valve 9, the lower ends of each throttle valve 9 are connected in parallel and then connected to the A port of the three-position four-way reversing valve 7, and the outlet end of the coaxial hydraulic motor 6 is connected in series with the second check valve 52 and then connected between the first two-position four-way reversing valve 11 and the first check valve 51, the oil inlet 62 of the coaxial hydraulic motor 6 is connected to the A port of the third two-position four-way reversing valve 13, and the P port of the third two-position four-way reversing valve 13 is connected to the system pressure of the pump group. This connection is a bypass parallel connection mode of the coaxial hydraulic motor 6 and the low-pressure control part.

[0034] The front chamber circuits of the six hinged beam oil cylinders still use the second two-position four-way reversing valve 12 and the balance valve 2 to be connected in series. The upper ends of the six balance valves 2 are connected in parallel and then connected to the B port of the three-position four-way reversing valve 7.

[0035] In specific implementation, the hydraulic control system provided by this embodiment can be padded with a transition valve block at the position of the first two-position four-way reversing valve 11 on the valve plate of the hydraulic station of the prior art, and the first two-position four-way reversing valve 11 is installed from the transition valve block, and the first one-way valve 51 connected in series is installed, and the three-way is connected in series with the second one-way valve 52 and then connected to the oil outlet 63 of the coaxial hydraulic motor 6, while the oil inlet 62 of the coaxial hydraulic motor 6 is connected to the installed third two-position four-way reversing valve 13, and the P port of the third two-position four-way reversing valve 13 is connected to the system pressure of the pump group. In this way, the coaxial hydraulic motor 6 is installed at the lowest cost, and the hydraulic station of the prior art is upgraded.

[0036] The control method is: control the single-cylinder and three-cylinder forward modes of the six hinged beam cylinders to remain unchanged, and only in the filling step, the third two-position four-way reversing valve 13 is energized, and the hydraulic oil is filled and supplied from the coaxial hydraulic motor 6 to the six hinged beam cylinders, and the second two-position four-way reversing valve 12 and the balance valve 2 connected in series in the front cavity circuit have the same function and control method as Example 1.

[0037] In summary, the hydraulic system of the six-sided top press provided by the utility model is provided with a coaxial hydraulic motor 6 connected in series or bypass parallel. Since the displacement of each oil motor of the coaxial hydraulic motor 6 is the same and the coaxial forced speed is the same, constant volume oil supply to the six hinged beam cylinders is realized, and is not affected by the different damping of the hydraulic cylinders, the gravity of the different piston positions, the length and number of elbows of the hydraulic pipeline from the hydraulic station to the hinged beam cylinder, and the viscosity change caused by the oil temperature, etc. on the filling synchronization, and the starting synchronization of the filling step and the precise control of the filling displacement during the filling process are realized, so that the six-sided top press has excellent synchronization.

[0038] Obviously, the embodiments described above are only some embodiments of the present application, rather than all embodiments. The preferred embodiments of the present application are given in the accompanying drawings, but they do not limit the patent scope of the present application. The present application can be implemented in many different forms. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present application more thorough and comprehensive. Although the present application is described in detail with reference to the aforementioned embodiments, for those skilled in the art, it is still possible to modify the technical solutions recorded in the aforementioned specific implementation methods, or to perform equivalent replacement of some of the technical features therein. Any equivalent structure made using the contents of the specification and drawings of this application, directly or indirectly used in other related technical fields, is similarly within the scope of patent protection of this application.

Claims

1. A new type of hydraulic control system for a six-sided top press, including a low-pressure control part, a high-pressure control part and a pump group part, wherein the low-pressure control part includes an ultra-high-pressure hydraulic control one-way valve, a first two-position four-way reversing valve and a throttle valve respectively connected in series with the rear chambers of six hinged beam oil cylinders; the T port of the first two-position four-way reversing valve is connected to the return oil system pipeline; the six throttle valves are connected in parallel and then connected to the A port of the three-position four-way reversing valve, and the P port of the three-position four-way reversing valve is connected to the pump group system pressure; the characteristics are: It also includes a coaxial hydraulic motor, which includes six coaxially connected hydraulic motors. The six hydraulic motors replace the throttle valve and are connected in series between the first two-position four-way reversing valve and the three-position four-way reversing valve, or are connected in parallel with the corresponding throttle valve and the three-position four-way reversing valve bypass; the front chambers of the six hinged beam cylinders are respectively connected in series with the corresponding second two-position four-way reversing valve and the balancing valve, and are connected together and then connected to the B port of the three-position four-way reversing valve.

2. The novel hydraulic control system of the six-sided top press according to claim 1 is characterized in that: When the coaxial hydraulic motors replace the throttle valves in series, the oil outlets of the six hydraulic motors are connected to the P ports corresponding to the first two-position four-way reversing valves, and the oil inlets are connected to the A ports of the three-position four-way reversing valves.

3. The novel hydraulic control system of the six-sided top press according to claim 1 is characterized in that: When the coaxial hydraulic motors are bypassed in parallel, a corresponding first check valve is also connected in series between the throttle valve and the first two-position four-way reversing valve; the oil outlets of the six hydraulic motors are respectively connected in series with the corresponding second check valves and then connected between the corresponding first two-position four-way reversing valve P port and the first check valve, the oil inlet is connected to the A port of the third two-position four-way reversing valve, and the P port of the third two-position four-way reversing valve is connected to the pump group system pressure.

4. The novel hydraulic control system of the six-sided top press according to any one of claims 1 to 3 is characterized in that: Each hydraulic motor oil outlet chamber end of the coaxial hydraulic motor is also provided with a pressure regulating overflow valve and a third one-way valve.

5. The novel hydraulic control system of the six-sided top press according to any one of claims 1 to 3 is characterized in that: After the oil inlet passages of the six hydraulic motors of the coaxial hydraulic motor are connected, there is at least one common total oil inlet, while the oil outlets thereof are independent of each other.

6. The novel hydraulic control system of the six-sided top press according to any one of claims 1 to 3 is characterized in that: The second two-position four-way reversing valve is in a normally open state when not energized.

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