Variable supercharger with low fluctuation pressure ratio

Abstract

The utility model discloses a variable supercharger with a low fluctuation pressure ratio. The variable supercharger comprises a pressure applying end and a pressed end, the pressure applying end comprises a large pressure applying end and a small pressure applying end; the large pressure applying end comprises a large cylinder body, a large piston and a large piston rod, the large piston is arranged in an inner cavity of the large cylinder body in a sliding mode, one end of the large piston rod is fixed to the large piston, and the other end of the large piston rod extends into an inner cavity of the pressed end; the small pressure applying end comprises a small cylinder body and a small piston rod, a low-pressure pressurizing hole is formed in the large piston, and an inner cavity of the small cylinder body is formed by the low-pressure pressurizing hole; one end of the small piston rod is fixed at the bottom of the large cylinder body, and the other end of the small piston rod extends into an inner cavity of the small cylinder body; and a low-pressure conveying channel is arranged in the small piston rod. The supercharger has a low pressure ratio, a medium pressure ratio and a high pressure ratio, corresponding pressure ratios can be selected under different working conditions, the pressure fluctuation value can be reduced, especially under the low-pressure working condition, and the product forming quality is improved.

Description

Technical Field

[0001] The utility model relates to a supercharger, in particular to a low-fluctuation pressure ratio variable supercharger. Background Art

[0002] With the development of internal high (ultra-high) pressure molding technology, products in certain fields have increasingly higher requirements for molding water pressure during the molding process. For example, the molding process of some products is:

[0003] 1. Inject low-pressure water first: the water pressure fluctuation is required to be within 5Mpa-50Mpa and is ±0.5Mpa-±1Mpa.

[0004] 2. Then inject medium and high pressure water: the water pressure fluctuation value is required to be within 50Mpa-100Mpa and is ±3Mpa.

[0005] 3. Finally, inject ultra-high pressure water: the water pressure fluctuation value above ﹥100Mpa is required to be ±5Mpa.

[0006] The existing ultra-high pressure supercharger has a constant and large ratio of oil pressure to water pressure, which cannot meet the water pressure requirements of some products:

[0007] For example, when the water pressure needs to reach 250Mpa, based on the maximum operating pressure of the hydraulic system of 25Mpa, the ratio of the oil pressure of the booster to the water pressure is 1:10, or even higher. Assuming that the oil pressure fluctuation of the hydraulic system is ±0.3Mpa, the water pressure fluctuation value is: ±0.3MpaX10=±3Mpa﹥±1Mpa, which far exceeds the limit of low-pressure working conditions and does not meet the requirements of low-pressure working conditions. The product quality needs to be improved. Utility Model Content

[0008] The purpose of the present utility model is to overcome the above-mentioned problems and provide a low-fluctuation pressure ratio variable supercharger. The supercharger has low, medium and high pressure ratios, and the corresponding pressure ratio can be selected under different working conditions, which is beneficial to reducing the pressure fluctuation value, especially under low-pressure working conditions, and improving the quality of product molding.

[0009] The purpose of the utility model is achieved through the following technical solutions:

[0010] A low-fluctuation pressure ratio variable supercharger comprises a pressure-applying end and a pressure-receiving end;

[0011] The pressure-applying end includes a large pressure-applying end and a small pressure-applying end; the large pressure-applying end includes a large cylinder, a large piston, and a large piston rod, wherein the large piston is slidably disposed in the inner cavity of the large cylinder, one end of the large piston rod is fixed to the large piston, and the other end of the large piston rod extends into the inner cavity of the pressure-receiving end;

[0012] The small pressure-applying end includes a small cylinder and a small piston rod. A low-pressure boosting hole is provided on the large piston, and the low-pressure boosting hole constitutes the inner cavity of the small cylinder. One end of the small piston rod is fixed to the bottom of the large cylinder, and the other end of the small piston rod extends into the inner cavity of the small cylinder. A low-pressure delivery channel is provided in the small piston rod.

[0013] The area of ​​the pressurized end surface of the large piston acted upon by the hydraulic oil is larger than the cross-sectional area of ​​the inner cavity of the small cylinder, and the cross-sectional area of ​​the inner cavity of the small cylinder is larger than or equal to the cross-sectional area of ​​the inner cavity of the pressure end.

[0014] The working principle of the above low-fluctuation pressure ratio variable supercharger is as follows:

[0015] Under low-pressure conditions, hydraulic oil is only injected into the low-pressure delivery channel of the small piston rod. The hydraulic oil enters the inner cavity of the small cylinder and acts on the inner bottom surface of the small cylinder cavity, pushing the large piston toward the pressure end (equivalent to the small cylinder moving to increase pressure while the small piston rod remains stationary). The water at the pressure end is then pressurized through the large piston rod. Under this condition, assuming that the ratio of the cross-sectional area of ​​the inner cavity of the small cylinder to the cross-sectional area of ​​the inner cavity of the pressure end is 2:1, that is, the pressure ratio is 1:2, and the oil pressure fluctuation is ±0.3Mpa, then the water pressure fluctuation is ±0.3MpaX2=±0.6Mpa﹤±1Mpa, which meets the requirements of low-pressure conditions.

[0016] Under medium- and high-pressure operating conditions, hydraulic oil is only injected into the inner cavity of the large cylinder. After the hydraulic oil enters the inner cavity of the large cylinder, it acts on the pressurized end surface of the large piston (except for the area corresponding to the small piston rod), pushing the large piston toward the pressure end, and then pressurizing the water at the pressure end through the large piston rod. Under this operating condition, assuming that the ratio of the area of ​​the hydraulic oil acting on the pressurized end surface of the large piston to the cross-sectional area of ​​the inner cavity of the pressure end is 8:1, that is, the pressure ratio is 1:8, and the oil pressure fluctuation is ±0.3Mpa, then the water pressure fluctuation value is ±0.3MpaX8=±2.4Mpa﹤±3Mpa, which meets the requirements of medium- and high-pressure operating conditions.

[0017] Under high-pressure conditions, hydraulic oil is simultaneously injected into the inner cavity of the large cylinder and into the low-pressure delivery channel of the small piston rod. The two hydraulic oils act on the pressurizing end surface of the large piston and the inner bottom surface of the inner cavity of the small cylinder, respectively, pushing the large piston toward the pressure-receiving end. The water pressure at the pressure-receiving end is then increased through the large piston rod. Under this condition, assuming the ratio of the total area of ​​the pressure-receiving end to the cross-sectional area of ​​the inner cavity of the pressure-receiving end is 10:1, that is, the pressure ratio is 1:10, and the oil pressure fluctuation is ±0.3 MPa, then the water pressure fluctuation is ±0.3 MPa x 10 = ±3 MPa < ±5 MPa, which meets the requirements of high-pressure conditions.

[0018] In a preferred embodiment of the present invention, a mounting hole is provided at the bottom of the large cylinder, through which one end of the small piston rod passes and is fixed to the bottom of the large cylinder. Thus, under the propulsion of hydraulic oil, the small piston rod remains stationary while the small cylinder (large piston) moves relative to it, thereby also achieving the boosting effect.

[0019] In a preferred embodiment of the present invention, the small pressure-applying end further includes a small piston, and the small piston is integrally provided with the small piston rod.

[0020] In a preferred embodiment of the present invention, the small piston rod is dynamically sealed to the hole wall of the low-pressure boost hole of the large piston.

[0021] In a preferred embodiment of the present invention, the ratio of the area of ​​the hydraulic oil acting on the pressurizing end surface of the large piston to the cross-sectional area of ​​the inner cavity of the pressure-receiving end is greater than or equal to 2:1.

[0022] In a preferred embodiment of the present invention, the ratio of the cross-sectional area of ​​the inner cavity of the small cylinder to the cross-sectional area of ​​the inner cavity of the pressure-receiving end is less than or equal to 2:1.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. The low-fluctuation pressure ratio variable supercharger of the utility model is provided with a large pressure end and a small pressure end. Not only can the large pressure end or the small pressure end be used separately, but the large pressure end and the small pressure end can also be used simultaneously to obtain low, medium and high different pressure ratios, thereby selecting the corresponding pressure ratio under different working conditions, which is beneficial to reducing the pressure fluctuation value, especially under low-pressure working conditions, and improving the quality of product molding.

[0025] 2. By integrating the small pressure end into the large pressure end, the large piston acts as a small cylinder, which not only makes the structure very compact and occupies a smaller space, but also reduces the cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1-3 This is a cross-sectional view of the low-fluctuation pressure ratio variable supercharger of the present invention under different working conditions, where the arrows indicate the flow direction of the hydraulic oil. DETAILED DESCRIPTION

[0027] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described below in conjunction with embodiments and drawings, but the implementation methods of the present invention are not limited thereto.

[0028] Referring to 1-3, the low-fluctuation pressure ratio variable supercharger of this embodiment includes a pressure-applying end (oil cylinder) and a pressure-receiving end 1 (water cylinder); the pressure-applying end includes a large pressure-applying end and a small pressure-applying end, that is, a large oil cylinder and a small oil cylinder; the large oil cylinder includes a large cylinder body 2, a large piston 3 and a large piston rod 4, the large piston 3 is slidably arranged in the inner cavity of the large cylinder body 2, one end of the large piston rod 4 is fixed on the large piston 3, and the other end of the large piston rod 4 extends to the inner cavity of the water cylinder 1.

[0029] The small oil cylinder includes a small cylinder body and a small piston rod 5. A low-pressure boosting hole 3-1 is provided on the large piston 3, and the low-pressure boosting hole 3-1 constitutes the inner cavity of the small cylinder body; one end of the small piston rod 5 is fixed to the bottom of the large cylinder body 2, and the other end of the small piston rod 5 extends into the inner cavity of the small cylinder body; a low-pressure delivery channel 5-1 is provided in the small piston rod 5; the area of ​​the boosting end face of the large piston 3 on which the hydraulic oil acts is larger than the cross-sectional area of ​​the inner cavity of the small cylinder body, and the cross-sectional area of ​​the inner cavity of the small cylinder body is greater than or equal to the cross-sectional area of ​​the inner cavity of the water cylinder 1.

[0030] Furthermore, a mounting through hole is provided at the bottom of the large cylinder 2, and one end of the small piston rod 5 passes through the mounting through hole and is fixed to the bottom of the large cylinder 2. In this way, under the push of the hydraulic oil, the small piston rod 5 remains stationary, and the small cylinder (large piston 3) moves relatively, which can also complete the boosting work.

[0031] Furthermore, the small oil cylinder also includes a small piston, which is integrally arranged with the small piston rod 5.

[0032] Furthermore, the small piston rod 5 is dynamically sealed to the hole wall of the low-pressure boost hole 3 - 1 of the large piston 3 .

[0033] Furthermore, the ratio of the area of ​​the pressurized end surface of the large piston 3 acted upon by the hydraulic oil to the cross-sectional area of ​​the inner cavity of the water cylinder 1 is greater than or equal to 2:1.

[0034] Furthermore, the ratio of the cross-sectional area of ​​the inner cavity of the small cylinder body to the cross-sectional area of ​​the inner cavity of the water tank 1 is less than or equal to 2:1.

[0035] Referring to 1-3, the working principle of the low-fluctuation pressure ratio variable supercharger of this embodiment is as follows:

[0036] Under low-pressure working conditions, only the hydraulic oil is injected into the low-pressure delivery channel 5-1 of the small piston rod 5, such as Figure 1, hydraulic oil enters the inner cavity of the small cylinder and acts on the inner bottom surface of the small cylinder, pushing the large piston 3 toward the water cylinder 1 (equivalent to the small cylinder moving to increase pressure while the small piston rod 5 remains stationary). This in turn increases the pressure of the water in water cylinder 1 via the large piston rod 4. Under this operating condition, assuming the ratio of the cross-sectional area of ​​the inner cavity of the small cylinder to the cross-sectional area of ​​the inner cavity of water cylinder 1 is 2:1, that is, the pressure ratio is 1:2, and the oil pressure fluctuation is ±0.3 MPa, then the water pressure fluctuation is ±0.3 MPa X 2 = ±0.6 MPa < ±1 MPa, which meets the requirements of low-pressure operating conditions.

[0037] Under medium and high pressure working conditions, only hydraulic oil is injected into the inner cavity of the large cylinder 2, such as Figure 2 After the hydraulic oil enters the inner cavity of the large cylinder 2, it acts on the pressurizing end surface of the large piston 3 (except for the area corresponding to the small piston rod 5), pushing the large piston 3 toward the water cylinder 1. The water in the water cylinder 1 is then pressurized via the large piston rod 4. Under this operating condition, assuming the ratio of the area of ​​the hydraulic oil acting on the pressurizing end surface of the large piston to the cross-sectional area of ​​the inner cavity of the pressure-receiving end is 8:1, that is, the pressure ratio is 1:8, and the oil pressure fluctuation is ±0.3 MPa, then the water pressure fluctuation is ±0.3 MPa X 8 = ±2.4 MPa < ±3 MPa, which meets the requirements of medium- and high-pressure operating conditions.

[0038] Under high pressure working conditions, hydraulic oil is injected into the inner cavity of the large cylinder 2 and hydraulic oil is injected into the low pressure delivery channel 5-1 of the small piston rod 5 at the same time. Figure 3 Hydraulic oil acts on the pressurizing end surface of large piston 3 and the inner bottom surface of the small cylinder cavity, respectively, pushing large piston 3 toward water cylinder 1. This in turn pressurizes the water in water cylinder 1 via large piston rod 4. Under these operating conditions, assuming the ratio of the total area of ​​the oil cylinder to the cross-sectional area of ​​the water cylinder cavity is 10:1, or a pressure ratio of 1:10, and the oil pressure fluctuation is ±0.3 MPa, then the water pressure fluctuation is ±0.3 MPa x 10 = ±3 MPa < ±5 MPa, meeting the high-pressure operating requirements.

[0039] The above is a preferred embodiment of the present invention, but the embodiment of the present invention is not limited to the above content. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be considered as equivalent replacement methods and are included in the scope of protection of the present invention.

Claims

1. A low-fluctuation pressure ratio variable supercharger, comprising a pressure-applying end and a pressure-receiving end; characterized in that: The pressure-applying end includes a large pressure-applying end and a small pressure-applying end; the large pressure-applying end includes a large cylinder, a large piston, and a large piston rod, wherein the large piston is slidably disposed in the inner cavity of the large cylinder, one end of the large piston rod is fixed to the large piston, and the other end of the large piston rod extends into the inner cavity of the pressure-receiving end; The small pressure-applying end includes a small cylinder and a small piston rod. A low-pressure boosting hole is provided on the large piston, and the low-pressure boosting hole constitutes the inner cavity of the small cylinder. One end of the small piston rod is fixed to the bottom of the large cylinder, and the other end of the small piston rod extends into the inner cavity of the small cylinder. A low-pressure delivery channel is provided in the small piston rod. The area of ​​the pressurized end surface of the large piston on which the hydraulic oil acts is larger than the cross-sectional area of ​​the inner cavity of the small cylinder, and the cross-sectional area of ​​the inner cavity of the small cylinder is larger than or equal to the cross-sectional area of ​​the inner cavity of the pressure-receiving end.

2. The low-fluctuation pressure ratio variable supercharger according to claim 1, characterized in that: A mounting through hole is provided at the bottom of the large cylinder body, and one end of the small piston rod passes through the mounting through hole and is fixed to the bottom of the large cylinder body.

3. The low-fluctuation pressure ratio variable supercharger according to claim 1, characterized in that: The small pressure-applying end further comprises a small piston, which is integrally arranged with the small piston rod.

4. The low-fluctuation pressure ratio variable supercharger according to claim 1, characterized in that: The small piston rod is dynamically sealed with the hole wall of the low-pressure boost hole of the large piston.

5. The low-fluctuation pressure ratio variable supercharger according to claim 1, characterized in that: The ratio of the area of ​​the pressurizing end surface of the large piston on which the hydraulic oil acts to the cross-sectional area of ​​the inner cavity of the pressure-receiving end is greater than or equal to 2:

1.

6. The low-fluctuation pressure ratio variable supercharger according to claim 1, characterized in that: The ratio of the cross-sectional area of ​​the inner cavity of the small cylinder to the cross-sectional area of ​​the inner cavity of the pressure-receiving end is less than or equal to 2:1.

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