Punch cylinder control method, punch cylinder, and punch press

Abstract

The present application belongs to the technical field of oil cylinder, and particularly relates to a stamping oil cylinder control method, a stamping oil cylinder and a punch press. The stamping oil cylinder control method comprises the following steps: S1, a servo control valve is configured to be in a conduction state to make an inner ring oil path connect an upper chamber and a lower chamber of an oil cylinder body, and a piston rod is driven to move downward relative to the oil cylinder body to make the oil in the lower chamber flow into the upper chamber through the inner ring oil path; and S3, the servo control valve is configured to be in a closed state to cut off the inner ring oil path, and the oil in the lower chamber of the oil cylinder body is pumped into the upper chamber through an outer ring oil path to make the piston rod feed at a low speed to a lowest point of a stroke. The stamping oil cylinder control method, the stamping oil cylinder and the punch press connect the upper chamber and the lower chamber of the oil cylinder body through the inner ring oil path, make the oil in the lower chamber quickly flow into the upper chamber through the extrusion of the piston rod in the process of moving downward of the piston rod, cancel the intervention of the oil pump, and thus the displacement demand of the oil pump is smaller.

Description

Technical Field

[0001] This invention belongs to the field of hydraulic cylinder technology, specifically relating to stamping hydraulic cylinders, and more particularly to a stamping hydraulic cylinder control method, a stamping hydraulic cylinder, and a stamping machine. Background Technology

[0002] A stamping press is a type of equipment widely used in the field of metal sheet processing. It achieves precise cutting, punching, and forming of sheet metal through stamping. The core component of a stamping press is the stamping cylinder.

[0003] The precision stamping process is generally divided into four stages: 1. High-speed pressing and feeding stage; 2. Deceleration die and clamping stage; 3. Low-speed working pressing and holding stage; 4. Demolding and return stage. Among them, the single stamping cycle is generally only two seconds. At the same time, the third stage of stamping has a low speed and a fixed duration requirement. Therefore, the first, second and fourth stages need to be completed as quickly as possible.

[0004] For example, a sheet metal filling and forming hydraulic press with the publication number "CN100594078C" uses a composite main cylinder and a large filling valve for synchronous use; however, the composite main cylinder in the above structure uses an external oil pump connected to an external ring oil circuit to directly pump oil to the upper and lower chambers to control the piston rod to lift and lower to achieve four stages of stamping. This control method has a large demand for oil and requires a large flow oil pump.

[0005] Therefore, how to reduce the flow rate of the oil pump while maintaining stamping efficiency is a technical problem that urgently needs to be solved by those skilled in the art.

[0006] It should be noted that the information disclosed in this background section is only for understanding the background technology of the present application concept, and therefore, the above description is not considered to constitute prior art information. Summary of the Invention

[0007] This disclosure provides at least one method for controlling a stamping cylinder, a stamping cylinder, and a stamping machine.

[0008] In a first aspect, embodiments of this disclosure provide a method for controlling a stamping cylinder, comprising: step S1, a servo control valve is configured to be in an on state, such that an inner ring oil circuit connects the upper chamber and the lower chamber of the cylinder body, and a piston rod is driven to move downward relative to the cylinder body, causing oil in the lower chamber to flow into the upper chamber through the inner ring oil circuit; step S2, during the downward movement of the piston rod, the upper die pushes the upper die to press against the stamped part, and moves the upper die to its lowest stroke point; step S3, the servo control valve is configured to be in a closed state to cut off the inner ring oil circuit, and oil in the lower chamber of the cylinder body is pumped into the upper chamber through an outer ring oil circuit, so that the piston rod is fed at a low speed to its lowest stroke point; step S4, the servo control valve is configured to be in an on state, such that an inner ring oil circuit connects the upper chamber and the lower chamber of the cylinder body, and a piston rod is driven to move upward relative to the cylinder body, causing oil in the upper chamber to flow into the lower chamber through the inner ring oil circuit.

[0009] In an optional embodiment, in step S3, the method of pumping the oil in the lower chamber of the cylinder body into the upper chamber through the outer ring oil circuit includes: the outer ring oil circuit is used to connect an external oil pump, and the oil in the lower chamber of the cylinder body is pumped into the upper chamber by the drive of the oil pump.

[0010] In an optional embodiment, the outer ring oil circuit includes an upper chamber oil port and a lower chamber oil port; wherein the control end of the servo control valve extends into the inner ring oil circuit; both the upper chamber oil port and the lower chamber oil port are connected to the inner ring oil circuit; the connection point between the upper chamber oil port and the inner ring oil circuit and the connection point between the lower chamber oil port and the inner ring oil circuit are respectively located on both sides of the control end of the servo control valve; in step S3, the method of pumping the oil in the lower chamber of the cylinder body into the upper chamber through the outer ring oil circuit includes: the upper chamber oil port and the lower chamber oil port are used to connect to an external oil pump, and the oil in the lower chamber of the cylinder body is pumped into the upper chamber by the drive of the oil pump.

[0011] Secondly, embodiments of this disclosure provide a method for controlling a stamping cylinder, comprising: dividing the cylinder body into an upper chamber and a lower chamber by setting a piston rod; connecting the upper chamber and the lower chamber by setting an inner ring oil circuit, and setting a servo control valve to control the opening and closing of the inner ring oil circuit; connecting the upper chamber and the lower chamber of the cylinder body by setting an outer ring oil circuit that can be connected to an external oil pump; when the piston rod is driven downward by an auxiliary cylinder, the servo control valve is configured to be in an on state so that the inner ring oil circuit connects the upper chamber and the lower chamber of the cylinder body, that is, the oil in the lower chamber flows into the upper chamber through the inner ring oil circuit until the mold is closed; and when the piston rod is driven downward by an oil pump, the servo control valve is configured to be in a closed state to cut off the inner ring oil circuit, and the oil in the lower chamber of the cylinder body is pumped into the upper chamber through the outer ring oil circuit so that the piston rod is fed at a low speed to its lowest stroke point.

[0012] In one optional embodiment, the outer ring oil circuit includes an upper chamber oil port and a lower chamber oil port; wherein the control end of the servo control valve extends into the inner ring oil circuit; both the upper chamber oil port and the lower chamber oil port are connected to the inner ring oil circuit; the connection point between the upper chamber oil port and the inner ring oil circuit and the connection point between the lower chamber oil port and the inner ring oil circuit are respectively located on both sides of the control end of the servo control valve; the upper chamber oil port and the lower chamber oil port are used to connect to an external oil pump, and the oil in the lower chamber of the cylinder body is pumped into the upper chamber by the drive of the oil pump.

[0013] Thirdly, embodiments of this disclosure provide a stamping cylinder, comprising: a cylinder body; a piston rod, wherein a piston portion thereon is located within the cylinder body to divide a chamber within the cylinder body into an upper chamber and a lower chamber; an inner ring oil passage, one end of which is connected to the upper chamber and the other end of which is connected to the lower chamber; an outer ring oil passage, one end of which is connected to the upper chamber and the other end of which is connected to the lower chamber; and a servo control valve configured to control the on / off state of the inner ring oil passage; wherein when the piston rod is driven downward by an auxiliary cylinder, the servo control valve is configured to be in an on state, so that oil in the lower chamber of the cylinder body flows into the upper chamber through the inner ring oil passage; and when the piston rod is driven downward by an oil pump, the servo control valve is configured to be in a closed state, so that oil in the lower chamber of the cylinder body is pumped into the upper chamber through the outer ring oil passage.

[0014] In one optional embodiment, the cylinder body includes: an upper mounting flange, a cylinder barrel, and a lower cylinder bottom; the upper mounting flange has at least one upper oil passage communicating with the upper chamber; the lower cylinder bottom has at least one lower oil passage communicating with the lower chamber; wherein the corresponding upper oil passage and the corresponding lower oil passage are connected by an oil pipe.

[0015] In one optional embodiment, the servo control valve is mounted on the upper mounting flange; wherein the control end of the servo control valve extends into the upper oil circuit to control the on / off state of the inner ring oil circuit; the outer ring oil circuit includes an upper chamber oil port and a lower chamber oil port; wherein the upper chamber oil port and the lower chamber oil port are located on the upper mounting flange; the upper chamber oil port and the lower chamber oil port are used to connect to an oil pump; the connection point between the upper chamber oil port and the inner ring oil circuit and the connection point between the lower chamber oil port and the inner ring oil circuit are respectively located on both sides of the control end of the servo control valve.

[0016] In one optional embodiment, an exhaust passage is provided inside the piston rod; wherein the inner end of the exhaust passage communicates with the lower chamber, and the outer end of the exhaust passage extends upward to the outside of the cylinder body; an exhaust connector is provided at the outer end of the exhaust passage to block the exhaust passage.

[0017] Fourthly, this disclosure provides a stamping machine, comprising: a frame on which an auxiliary oil cylinder, an oil pump, and a displacement sensor are mounted; a stamping oil cylinder as described above; the auxiliary oil cylinder being used to drive the lifting and lowering of a piston rod; the oil pump being used to connect to the outer annular oil circuit of the stamping oil cylinder; the displacement sensor being used to acquire position data of the piston rod; and a control module configured to be electrically connected to the auxiliary oil cylinder, the oil pump, the displacement sensor, and the servo control valve, and configured to execute the stamping oil cylinder control method as described above.

[0018] The beneficial effect of this invention is that the stamping cylinder control method, the stamping cylinder, and the stamping machine connect the upper and lower chambers of the cylinder body through an inner ring oil circuit. During the downward movement of the piston rod, the oil in the lower chamber is quickly discharged into the upper chamber by the compression of the piston rod, eliminating the need for the oil pump and thus reducing the displacement requirement of the oil pump.

[0019] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention are realized and obtained through the structures particularly pointed out in the description and the drawings.

[0020] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, preferred embodiments are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0021] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0022] Figure 1 A schematic diagram illustrating the principle of a stamping cylinder control method provided in this embodiment of the present disclosure; Figure 2 A simplified schematic diagram illustrating the principle of a stamping cylinder control method provided in this embodiment of the present disclosure; Figure 3 This is a schematic diagram of the structure of a stamping cylinder provided in an embodiment of the present disclosure; Figure 4 This is a schematic diagram of an inner ring oil circuit provided in an embodiment of the present disclosure; Figure 5 This is a schematic diagram of an oil supply circuit provided in an embodiment of the present disclosure; Figure 6 This is a schematic diagram of an exhaust channel provided in an embodiment of the present disclosure.

[0023] In the picture: 1. Cylinder body; 11. Upper chamber; 12. Lower chamber; 13. Upper mounting flange; 131. Upper oil passage; 14. Cylinder barrel; 15. Lower cylinder bottom; 151. Lower oil passage; 2. Piston rod; 20. Piston section; 21. Exhaust passage; 22. Exhaust connector; 3. Oil pipe; 31. Inner ring oil circuit; 51. Upper chamber oil port; 52. Lower chamber oil port; 32. Servo control valve; 4. Displacement sensor. Detailed Implementation

[0024] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the figures, the thickness of parts may be exaggerated or reduced for the purpose of effectively depicting the technical content.

[0026] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0027] like Figure 1 As shown, at least one embodiment provides a method for controlling a stamping cylinder, including steps S1 to S4.

[0028] like Figure 1 , Figure 2 As shown, in some embodiments, step S1 includes: the servo control valve 32 is configured to be in an on state so that the inner ring oil passage 31 connects the upper chamber 11 and the lower chamber 12 of the cylinder body 1, and the piston rod 2 is driven to move downward relative to the cylinder body 1 so that the oil in the lower chamber 12 flows into the upper chamber 11 through the inner ring oil passage 31.

[0029] In this embodiment, the piston rod 2 falls rapidly under the drive of the auxiliary cylinder to obtain greater kinetic energy. During the falling process, the piston rod 2 quickly discharges the oil in the lower chamber 12 to the upper chamber 11 through the inner ring oil passage 31 to achieve rapid feeding. During this process, the flow of oil does not require the intervention of the oil pump, and the displacement requirement of the oil pump is smaller.

[0030] like Figure 1 , Figure 2 As shown, in some embodiments, step S2 includes: the piston rod 2 pushes the upper die of the mold to press against the stamped part during the downward movement, and moves the upper die of the mold to the lowest point of its stroke.

[0031] Specifically, piston rod 2 is a double-ended piston rod, that is, the upper end of piston rod 2 extends out of the cylinder body 1 and is connected to the auxiliary cylinder, and the lower end of piston rod 2 extends out of the cylinder body 1 and can be used to install the upper mold.

[0032] In this embodiment, the downward movement of piston rod 2 is still driven by the auxiliary oil cylinder until piston rod 2 drives the upper mold to move to the lowest point of the upper mold stroke. At this time, the auxiliary oil cylinder stops driving piston rod 2 to move downward.

[0033] like Figure 1 , Figure 2 As shown, in some embodiments, step S3 includes: the servo control valve 32 is configured to be closed to cut off the inner ring oil circuit 31, and the oil in the lower chamber 12 of the cylinder body 1 is pumped into the upper chamber 11 through the outer ring oil circuit 5 so that the piston rod 2 is fed at low speed to its lowest point of stroke.

[0034] In this embodiment, after the displacement sensor 4 detects that the upper mold has been in place, the servo control valve 32 quickly disconnects the inner ring oil circuit 31, and the oil pump connected to the outer ring oil circuit 5 pumps the oil in the lower chamber 12 to the upper chamber 11. Driven by the oil pump, the piston rod 2 continues to feed and fall at a low speed until the lowest point of the piston rod 2's stroke, pushing the punch on the mold to complete the stamping. During this process, the descent height of the piston rod 2 accounts for a very small proportion of the entire stroke, so only a small displacement oil pump is needed to complete this action.

[0035] like Figure 1 , Figure 2 As shown, in some embodiments, step S4 includes: the servo control valve 32 is configured to be in an on state so that the inner ring oil passage 31 connects the upper chamber 11 and the lower chamber 12 of the cylinder body 1, and the piston rod 2 is driven to move upward relative to the cylinder body 1 so that the oil in the upper chamber 11 flows into the lower chamber 12 through the inner ring oil passage 31.

[0036] In this embodiment, after the displacement sensor 4 detects that the piston rod 2 has reached its lowest point of stroke, the servo control valve 32 quickly opens the inner ring oil circuit 31, the oil pump stops working, and the auxiliary oil cylinder drives the piston rod 2 to quickly rise back to allow the oil in the upper chamber 11 to flow into the lower chamber 12; during this process, the oil pump also does not need to work.

[0037] like Figure 1 , Figure 2As shown, in some embodiments, in step S3, the method of pumping the oil in the lower chamber 12 of the cylinder body 1 into the upper chamber 11 through the outer ring oil passage 5 includes: the outer ring oil passage 5 is used to connect an external oil pump, and the oil in the lower chamber 12 of the cylinder body 1 is pumped into the upper chamber 11 by the drive of the oil pump.

[0038] like Figure 1 , Figure 2 As shown, in some embodiments, the outer ring oil circuit 5 includes: an upper chamber oil port 51 and a lower chamber oil port 52; wherein the control end of the servo control valve 32 extends into the inner ring oil circuit 31; both the upper chamber oil port 51 and the lower chamber oil port 52 are connected to the inner ring oil circuit 31; the connection point between the upper chamber oil port 51 and the inner ring oil circuit 31 and the connection point between the lower chamber oil port 52 and the inner ring oil circuit 31 are respectively located on both sides of the control end of the servo control valve 32; in step S3, the method of pumping the oil in the lower chamber 12 of the cylinder body 1 into the upper chamber 11 through the outer ring oil circuit 5 includes: the upper chamber oil port 51 and the lower chamber oil port 52 are used to connect to an external oil pump, and the oil in the lower chamber 12 of the cylinder body 1 is pumped into the upper chamber 11 by the drive of the oil pump.

[0039] like Figure 2 As shown, at least one embodiment also provides a method for controlling a stamping cylinder, including: dividing the cylinder body 1 into an upper chamber 11 and a lower chamber 12 by setting a piston rod 2; connecting the upper chamber 11 and the lower chamber 12 by setting an inner ring oil passage 31, and setting a servo control valve 32 to control the opening and closing of the inner ring oil passage 31; and connecting the upper chamber 11 and the lower chamber 12 of the cylinder body 1 by setting an outer ring oil passage 5 that can be connected to an external oil pump.

[0040] In some embodiments, when the piston rod 2 is driven downward by the auxiliary cylinder, the servo control valve 32 is configured to be in an open state so that the inner ring oil passage 31 connects the upper chamber 11 and the lower chamber 12 of the cylinder body 1, that is, the oil in the lower chamber 12 flows into the upper chamber 11 through the inner ring oil passage 31 until the mold is closed; and when the piston rod 2 is driven downward by the oil pump, the servo control valve 32 is configured to be in a closed state to cut off the inner ring oil passage 31, and the oil in the lower chamber 12 of the cylinder body 1 is pumped into the upper chamber 11 through the outer ring oil passage 5 so that the piston rod 2 is fed at a low speed to its lowest stroke point.

[0041] In some embodiments, when the piston rod 2 is driven upward by the auxiliary oil cylinder, the servo control valve 32 is configured to be in the open state so that the inner ring oil passage 31 connects the upper chamber 11 and the lower chamber 12 of the cylinder body 1, that is, the oil in the upper chamber 11 flows into the lower chamber 12 through the inner ring oil passage 31 until it is reset.

[0042] In some embodiments, the outer ring oil circuit 5 includes an upper chamber oil port 51 and a lower chamber oil port 52; wherein the control end of the servo control valve 32 extends into the inner ring oil circuit 31; both the upper chamber oil port 51 and the lower chamber oil port 52 are connected to the inner ring oil circuit 31; the connection point between the upper chamber oil port 51 and the inner ring oil circuit 31 and the connection point between the lower chamber oil port 52 and the inner ring oil circuit 31 are located on both sides of the control end of the servo control valve 32; the upper chamber oil port 51 and the lower chamber oil port 52 are used to connect to an external oil pump, and the oil in the lower chamber 12 of the cylinder body 1 is pumped into the upper chamber 11 by the drive of the oil pump.

[0043] like Figures 3 to 6 As shown, at least one embodiment also provides a stamping cylinder, including: a cylinder body 1; a piston rod 2, on which a piston portion 20 is located within the cylinder body 1 to divide the chamber within the cylinder body 1 into an upper chamber 11 and a lower chamber 12; an inner ring oil passage 31, one end of which is connected to the upper chamber 11 and the other end of which is connected to the lower chamber 12; an outer ring oil passage 5, one end of which is connected to the upper chamber 11 and the other end of which is connected to the lower chamber 12; and a servo control valve 32 configured to control the on / off state of the inner ring oil passage 31.

[0044] In some embodiments, when the piston rod 2 is driven downward by the auxiliary cylinder, the servo control valve 32 is configured to be open so that the oil in the lower chamber 12 of the cylinder body 1 flows into the upper chamber 11 through the inner ring oil passage 31.

[0045] In this embodiment, the piston rod 2 falls rapidly under the drive of the auxiliary cylinder to obtain greater kinetic energy. During the falling process, the piston rod 2 quickly discharges the oil in the lower chamber 12 to the upper chamber 11 through the inner ring oil passage 31 to achieve rapid feeding. During this process, the flow of oil does not require the intervention of the oil pump, and the displacement requirement of the oil pump is smaller. At the same time, the piston rod 2 is not driven by the oil pump to fall, which makes the falling speed of the piston rod 2 faster.

[0046] In some embodiments, when the piston rod 2 is driven downward by the oil pump, the servo control valve 32 is configured to be closed, so that the oil in the lower chamber 12 of the cylinder body 1 is pumped into the upper chamber 11 through the outer ring oil circuit 5.

[0047] In this embodiment, the piston rod 2 continues to feed and fall at a low speed under the drive of the oil pump until the lowest point of the piston rod 2's stroke, pushing the punch on the mold to complete the stamping. During this process, the descent height of the piston rod 2 accounts for a very small proportion of the entire stroke, so only a small displacement oil pump is needed to complete this action.

[0048] In some embodiments, the piston rod 2 is a double-ended piston rod, that is, the upper end of the piston rod 2 extends out of the cylinder body 1 and is connected to the auxiliary cylinder, and the lower end of the piston rod 2 extends out of the cylinder body 1 and can be used to install the upper mold.

[0049] like Figure 3 As shown, in some embodiments, the cylinder body 1 includes: an upper mounting flange 13, a cylinder barrel 14, and a lower cylinder bottom 15.

[0050] like Figure 5 As shown, in some embodiments, the upper mounting flange 13 has at least one upper oil passage 131 communicating with the upper chamber 11.

[0051] like Figure 4 As shown, in some embodiments, at least one lower oil passage 151 communicating with the lower chamber 12 is provided in the lower cylinder bottom 15.

[0052] like Figure 4 As shown, in some embodiments, the corresponding upper oil passage 131 and the corresponding lower oil passage 151 are connected by an oil pipe 3.

[0053] like Figure 3 As shown, in some embodiments, a servo control valve 32 is disposed on the upper mounting flange 13; wherein the control end of the servo control valve 32 extends into the upper oil passage 131 to control the on / off state of the inner ring oil passage 31.

[0054] like Figure 3 As shown, in some embodiments, the outer ring oil passage 5 includes an upper chamber oil port 51 and a lower chamber oil port 52.

[0055] Specifically, the upper chamber oil port 51 and the lower chamber oil port 52 are provided on the upper mounting flange 13; the upper chamber oil port 51 and the lower chamber oil port 52 are used to connect to the oil pump; the connection point between the upper chamber oil port 51 and the inner ring oil circuit 31 and the connection point between the lower chamber oil port 52 and the inner ring oil circuit 31 are respectively located on both sides of the control end of the servo control valve 32.

[0056] In this embodiment, because the stamping cylinder moves at a high speed, air bubbles are easily formed inside. The accumulation of air bubbles inside the cylinder can easily cause problems such as damage to seals, abnormal noise, and reduced control accuracy. Therefore, in this embodiment, all the oil ports of the stamping cylinder are located at the top of the cylinder, which can expel the air inside the cylinder as much as possible.

[0057] like Figure 6 As shown, in some embodiments, an exhaust passage 21 is provided inside the piston rod 2; wherein the inner end of the exhaust passage 21 is connected to the lower chamber 12, and the outer end of the exhaust passage 21 extends upward to the outside of the cylinder body 1; an exhaust connector 22 is provided at the outer end of the exhaust passage 21 to block the exhaust passage 21.

[0058] In this embodiment, since the lower chamber 12 is an inverted structure, it is not conducive to gas discharge and is prone to gas accumulation. Therefore, this embodiment provides an exhaust channel 21 in the piston rod 2 and an exhaust connector 22 to facilitate the operator to exhaust gas periodically.

[0059] The stamping process of this stamping cylinder is as follows: In the first stage (high-speed downward feed stage): the servo control valve 32 is in the open state, the upper chamber 11 and the lower chamber 12 are connected through the inner ring oil circuit 31, the piston rod 2 falls rapidly under the drive of the auxiliary oil cylinder, at this time the oil flows rapidly from the lower chamber 12 to the upper chamber 11, realizing rapid feed.

[0060] In the second stage (deceleration mold and clamping stage): the stamping cylinder has obtained a large movement speed after the rapid feed in the first stage, and because the piston rod 2 itself is relatively heavy, the moving element has a large kinetic energy. In the clamping stage, the piston rod 2 impact force pushes the upper mold of the mold to clamp the stamped part.

[0061] In the third stage (low-speed pressing and holding stage): At this time, the upper die has been pressed and reached the lowest point of the upper die's stroke. After the displacement sensor 4 detects that the stroke has reached the end, the servo control valve 32 quickly disconnects the inner ring oil circuit 31, so that the upper chamber 11 and the lower chamber 12 are not connected. At this time, the outer ring oil circuit 5 pumps the oil from the lower chamber oil port 52 to the upper chamber oil port 51 through the oil pump. The piston rod 2 continues to feed and fall at a low speed under the drive of the oil pump, pushing the punch to complete the pressing process. At the same time, the oil will also pass through the heat exchanger to cool down the oil during the process of pumping from the lower chamber oil port 52 to the upper chamber oil port 51.

[0062] In the fourth stage (demolding return stage): At this time, the piston rod 2 has reached the lowest point of the stroke. The displacement sensor 4 detects again that the stroke has ended. The servo control valve 32 quickly opens the inner ring oil circuit 31, so that the upper chamber 11 and the lower chamber 12 are connected. The piston rod 2 of the stamping cylinder rises rapidly under the drive of the auxiliary cylinder to complete the rapid return.

[0063] Therefore, it can be seen that, except for the third stage, the stamping cylinder is in an unloaded state in the other stages; the first and second stages can also be combined into one stage.

[0064] At least one embodiment also provides a stamping machine, including: a frame on which an auxiliary cylinder, an oil pump, and a displacement sensor are disposed; a stamping cylinder; the auxiliary cylinder is used to drive the lifting and lowering of a piston rod 2; the oil pump is used to connect to the outer annular oil circuit 5 of the stamping cylinder; the displacement sensor is used to acquire position data of the piston rod 2; and a control module is configured to be electrically connected to the auxiliary cylinder, the oil pump, the displacement sensor, and the servo control valve 32, and is configured to execute the stamping cylinder control method described above.

[0065] In this embodiment, the control module receives signal data from the displacement sensor 4 to obtain the downward movement distance of the piston rod 2, thereby precisely controlling the on / off state of the servo control valve 32; wherein, the displacement sensor 4 can obtain the position of the upper mold by obtaining the downward movement distance of the piston rod 2.

[0066] In summary, this stamping cylinder control method, stamping cylinder, and stamping machine, by setting an inner ring oil circuit 31 to connect the upper chamber 11 and the lower chamber 12 of the cylinder body 1, allows the oil in the lower chamber 12 to be quickly discharged into the upper chamber 11 by the compression of the piston rod 2 during the downward movement of the piston rod 2, thus eliminating the need for the intervention of the oil pump and reducing the displacement requirement of the oil pump.

[0067] In this document, when it is said that the first component is located on the second component, this can mean that the first component can be directly formed on the second component, or that the third component can be inserted between the first component and the second component.

[0068] In this document, when an element or layer is referred to as being “located,” “joined to,” “connected to,” “attached to,” or “coupled to” another element or layer, it may be directly located, joined, connected, attached to, or coupled to the other element or layer, or there may be an intermediate element or layer.

[0069] In the description of the embodiments of the present invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the present invention based on the specific circumstances.

[0070] Spatially relative terms, such as “inside,” “outside,” “below,” “below,” “down,” “above,” “up,” etc., may be used herein to describe the relationship between one element or feature illustrated in the figures and another element or feature. In addition to the orientations depicted in the figures, spatially relative terms may be intended to cover different orientations of the apparatus in use or operation.

[0071] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A method for controlling a stamping cylinder, characterized in that, include: In step S1, the servo control valve (32) is configured to be in the open state so that the inner ring oil passage (31) connects the upper chamber (11) and the lower chamber (12) of the cylinder body (1), and the piston rod (2) is driven to move down relative to the cylinder body (1) so that the oil in the lower chamber (12) flows into the upper chamber (11) through the inner ring oil passage (31). In step S2, the piston rod (2) pushes the upper die of the mold to press the stamped part during the downward movement, and moves the upper die of the mold to the lowest point of its stroke; In step S3, the servo control valve (32) is configured to be closed to cut off the inner ring oil circuit (31), and the oil in the lower chamber (12) of the cylinder body (1) is pumped into the upper chamber (11) through the outer ring oil circuit (5) so that the piston rod (2) is fed at low speed to its lowest point of stroke. In step S4, the servo control valve (32) is configured to be in the on state so that the inner ring oil passage (31) connects the upper chamber (11) and the lower chamber (12) of the cylinder body (1), and the piston rod (2) is driven to move upward relative to the cylinder body (1) so that the oil in the upper chamber (11) flows into the lower chamber (12) through the inner ring oil passage (31).

2. The stamping cylinder control method as described in claim 1, characterized in that, In step S3, the method of pumping the oil in the lower chamber (12) of the cylinder body (1) into the upper chamber (11) through the outer ring oil passage (5) includes: The outer ring oil circuit (5) is used to connect an external oil pump, which drives the oil in the lower chamber (12) of the cylinder body (1) to the upper chamber (11).

3. The stamping cylinder control method as described in claim 2, characterized in that, The outer ring oil passage (5) includes: an upper chamber oil port (51) and a lower chamber oil port (52); wherein The control end of the servo control valve (32) extends into the inner ring oil circuit (31); Both the upper cavity oil port (51) and the lower cavity oil port (52) are connected to the inner ring oil circuit (31); The connection point between the upper chamber oil port (51) and the inner ring oil circuit (31) and the connection point between the lower chamber oil port (52) and the inner ring oil circuit (31) are located on both sides of the control end of the servo control valve (32); In step S3, the method of pumping the oil in the lower chamber (12) of the cylinder body (1) into the upper chamber (11) through the outer ring oil passage (5) includes: The upper chamber oil port (51) and the lower chamber oil port (52) are used to connect to an external oil pump. The oil pump drives the oil in the lower chamber (12) of the cylinder body (1) to the upper chamber (11).

4. A method for controlling a stamping cylinder, characterized in that, include: The cylinder body (1) is divided into an upper chamber (11) and a lower chamber (12) by setting a piston rod (2). The upper chamber (11) and the lower chamber (12) are connected by setting an inner ring oil circuit (31), and a servo control valve (32) is set to control the opening and closing of the inner ring oil circuit (31); By setting an outer ring oil circuit (5) that can be connected to an external oil pump, the outer ring oil circuit (5) is connected to the upper chamber (11) and the lower chamber (12) of the cylinder body (1). When the piston rod (2) is driven downward by the auxiliary oil cylinder, the servo control valve (32) is configured to be open, so that the inner ring oil passage (31) connects the upper chamber (11) and the lower chamber (12) of the cylinder body (1), that is, the oil in the lower chamber (12) flows into the upper chamber (11) through the inner ring oil passage (31) until the mold is closed; and When the piston rod (2) is driven down by the oil pump, the servo control valve (32) is configured to close to cut off the inner ring oil circuit (31). The oil in the lower chamber (12) of the cylinder body (1) is pumped into the upper chamber (11) through the outer ring oil circuit (5) so that the piston rod (2) is fed at low speed to the lowest point of its stroke.

5. The stamping cylinder control method as described in claim 4, characterized in that, The outer ring oil passage (5) includes: an upper chamber oil port (51) and a lower chamber oil port (52); wherein The control end of the servo control valve (32) extends into the inner ring oil circuit (31); Both the upper cavity oil port (51) and the lower cavity oil port (52) are connected to the inner ring oil circuit (31); The connection point between the upper chamber oil port (51) and the inner ring oil circuit (31) and the connection point between the lower chamber oil port (52) and the inner ring oil circuit (31) are located on both sides of the control end of the servo control valve (32); The upper chamber oil port (51) and the lower chamber oil port (52) are used to connect to an external oil pump. The oil pump drives the oil in the lower chamber (12) of the cylinder body (1) to the upper chamber (11).

6. A stamping cylinder, characterized in that, include: Hydraulic cylinder body (1); The piston rod (2) has a piston part (20) located inside the cylinder body (1) to divide the chamber inside the cylinder body (1) into an upper chamber (11) and a lower chamber (12). The inner ring oil circuit (31) is connected at one end to the upper chamber (11) and at the other end to the lower chamber (12); The outer ring oil circuit (5) is connected at one end to the upper chamber (11) and at the other end to the lower chamber (12); The servo control valve (32) is configured to control the on / off state of the inner loop oil circuit (31); in When the piston rod (2) is driven to move downward by the auxiliary oil cylinder, the servo control valve (32) is configured to be open so that the oil in the lower chamber (12) of the cylinder body (1) flows into the upper chamber (11) through the inner ring oil passage (31); as well as When the piston rod (2) is driven to move downward by the oil pump, the servo control valve (32) is configured to be closed, so that the oil in the lower chamber (12) of the cylinder body (1) is pumped into the upper chamber (11) through the outer ring oil circuit (5).

7. The stamping cylinder as described in claim 6, characterized in that, The cylinder body (1) includes: an upper mounting flange (13), a cylinder barrel (14), and a lower cylinder bottom (15); The upper mounting flange (13) has at least one upper oil passage (131) that communicates with the upper chamber (11). At least one lower oil passage (151) communicating with the lower chamber (12) is provided in the bottom of the lower cylinder (15). The upper oil passage (131) and the lower oil passage (151) are connected by an oil pipe (3).

8. The stamping cylinder as described in claim 7, characterized in that, The servo control valve (32) is mounted on the upper mounting flange (13); wherein The control end of the servo control valve (32) extends into the upper oil circuit (131) to control the opening and closing of the inner ring oil circuit (31); The outer ring oil passage (5) includes: an upper chamber oil port (51) and a lower chamber oil port (52); wherein The upper cavity oil port (51) and the lower cavity oil port (52) are opened on the upper mounting flange (13); The upper chamber oil port (51) and the lower chamber oil port (52) are used to connect to the oil pump; The connection point between the upper chamber oil port (51) and the inner ring oil circuit (31) and the connection point between the lower chamber oil port (52) and the inner ring oil circuit (31) are located on both sides of the control end of the servo control valve (32).

9. The stamping cylinder as described in claim 8, characterized in that, An exhaust passage (21) is provided inside the piston rod (2); wherein The inner end of the exhaust passage (21) is connected to the lower chamber (12), and the outer end of the exhaust passage (21) extends upward to the outside of the cylinder body (1). An exhaust connector (22) is provided at the outer end of the exhaust passage (21) to block the exhaust passage (21).

10. A stamping machine, characterized in that, include: The frame is equipped with an auxiliary hydraulic cylinder, an oil pump, and a displacement sensor (4). The stamping cylinder as described in any one of claims 6-9; The auxiliary hydraulic cylinder is used to drive the piston rod (2) to rise and fall; The oil pump is used to connect to the outer ring oil circuit (5) of the stamping cylinder. The displacement sensor (4) is used to acquire the position data of the piston rod (2); The control module is configured to be electrically connected to the auxiliary cylinder, the oil pump, the displacement sensor, the servo control valve (32), and is configured to perform the stamping cylinder control method as described in claim 1 or 4.

Images