Pressure differential reversing impact cylinder

Abstract

The application discloses a differential pressure reversing impact oil cylinder, which comprises a cylinder body and a piston rod, one end of the piston rod is slidably connected in the cylinder body, and the other end is an impact end; the piston rod and the cylinder body are provided with a first cavity and a second cavity, the first cavity is located between the second cavity and the impact end, the end area of the second cavity is larger than that of the first cavity, and the volume of the first cavity and the second cavity reversibly changes with the sliding of the piston rod; the cylinder body is provided with an oil inlet oil way and an oil return oil way, the oil inlet oil way is communicated with the first cavity, and the oil inlet oil way and the oil return oil way are communicated with the second cavity in a staggered manner during the sliding of the piston rod. The application is applied to the field of hydraulic oil cylinders, the oil way switching only lies in whether the second cavity is communicated with the oil inlet oil way and the oil outlet oil way, and the oil way switching is realized by the impact and return movement of the piston rod, so that the reversing is realized without reversing valve, the impact performance is strong, the structure of the impact oil cylinder is effectively simplified, and the cost is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydraulic oil cylinder, in particular to a differential pressure reversing impact oil cylinder. BACKGROUND

[0002] Impact oil cylinder is widely used in various industries for impact operation, but there are problems such as complex structure, high cost and large size.

[0003] The traditional impact oil cylinder, such as the structure of the breaking hammer, relies on the reversing valve core to switch the oil circuit, and the reversing valve is also in high-frequency reciprocating motion while the impact piston is in high-frequency motion. As disclosed in patent publication No. CN109519441A, a straight push type impact oil cylinder. Therefore, it is necessary to ensure the wear resistance and machining accuracy of the reversing valve and the impact piston. At the same time, since the reversing relies on the reversing valve core to switch the oil circuit, it is necessary to ensure the corresponding connection of the connected oil circuit, and the structure is relatively complex. Impact relies on the impact piston, and reversing relies on the reversing valve. In order to ensure smooth oil circuit and performance, the volume is often large. SUMMARY

[0004] In view of the problems of complex structure, high cost and large size of the impact oil cylinder in the prior art, the present application provides a differential pressure reversing impact oil cylinder, which can realize reversing without reversing valve and has strong impact performance, and can effectively simplify the structure of the impact oil cylinder and reduce the cost.

[0005] To achieve the above purpose, the present application provides a differential pressure reversing impact oil cylinder, which comprises a cylinder body and a piston rod, one end of the piston rod being slidably connected in the cylinder body, and the other end being an impact end;

[0006] The first cavity and the second cavity are provided between the piston rod and the cylinder body, the first cavity is located between the second cavity and the impact end, the end area of the second cavity is larger than that of the first cavity, and the volume of the first cavity and the second cavity changes reversely with the sliding of the piston rod;

[0007] The cylinder body is provided with an oil inlet oil circuit and an oil return oil circuit, the oil inlet oil circuit communicates with the first cavity, and the oil inlet oil circuit and the oil return oil circuit communicate with the second cavity in a staggered manner during the sliding of the piston rod.

[0008] In one embodiment, a first oil circuit is provided in the cylinder body, one end of the first oil circuit communicates with the oil inlet oil circuit, and the other end communicates with the first cavity.

[0009] In one embodiment, the impact oil cylinder further comprises a first oil storage structure, a second oil circuit is provided in the cylinder body, and a first end of the second oil circuit communicates with the first oil storage structure.

[0010] The first oil passage is provided with a first one-way valve, and the second end of the second oil passage is communicated with the first oil passage, and the communication position is located between the first one-way valve and the first cavity.

[0011] In one of the embodiments, a first overflow valve is arranged on the first connecting pipeline between the first oil storage structure and the second oil passage.

[0012] In one of the embodiments, a third oil passage is arranged in the cylinder body, the first end of the third oil passage is communicated with the oil inlet passage, and the second end is located on the inner wall of the cylinder body.

[0013] The third oil passage is provided with a second one-way valve, and the second end of the third oil passage is communicated with the second cavity or is blocked by the piston rod during the sliding process of the piston rod.

[0014] In one of the embodiments, a fourth oil passage is arranged on the piston rod, and the first end of the fourth oil passage is communicated with the second cavity.

[0015] The second end of the third oil passage is communicated with the second end of the fourth oil passage or is blocked by the piston rod during the sliding process of the piston rod.

[0016] In one of the embodiments, the piston rod is a straight rod structure.

[0017] The first cavity is located between the side wall of the piston rod and the inner wall of the cylinder body, and the second cavity is located between the end wall of the piston rod and the inner wall of the cylinder body.

[0018] The first end of the fourth oil passage is located on the side wall of the piston rod, and the second end of the fourth oil passage is located on the end wall of the piston rod.

[0019] In one of the embodiments, the piston rod includes coaxial first rod body and second rod body, and the first end of the second rod body is connected with the first end of the first rod body, and the second end of the first rod body is the impact end.

[0020] The first cavity is located between the side wall of the first rod body and the inner wall of the cylinder body, and the second cavity is located between the side wall of the second rod body and the inner wall of the cylinder body.

[0021] The first end of the fourth oil passage is located on the side wall of the first rod body, and the second end of the fourth oil passage is located on the side wall of the second rod body.

[0022] In one of the embodiments, the fourth oil passage has a plurality of first ends, and each first end of the fourth oil passage is annularly and uniformly distributed on the side wall of the second rod body.

[0023] In one embodiment, an oil drain chamber is provided between the second end of the second rod and the inner wall of the cylinder, and an oil drain hole communicating with the oil drain chamber is provided on the cylinder.

[0024] In one embodiment, the impact cylinder further includes a second oil storage structure, and the cylinder body is provided with a fifth oil passage, one end of which is connected to the second oil storage structure and the other end of which is connected to the second cavity.

[0025] In one embodiment, a second overflow valve is provided on the connecting pipeline between the second oil storage structure and the fifth oil circuit.

[0026] In one embodiment, the impact cylinder further includes a third oil storage structure, and the cylinder body is provided with a sixth oil passage, the first end of which is connected to the third oil storage structure.

[0027] The second end of the sixth oil passage is located on the inner wall of the cylinder, and the second end of the sixth oil passage is connected to or separated from the first cavity during the sliding of the piston rod.

[0028] The present invention has the following beneficial technical effects:

[0029] 1. The oil circuit switching in this invention is only determined by whether the second chamber is connected to the inlet oil circuit and the outlet oil circuit, and the oil circuit switching is achieved by the impact and return movement of the piston rod. While achieving the switching without a reversing valve, it also has strong impact performance.

[0030] 2. The present invention has a simple structure. Due to the different impact realization principle, the impact cylinder of the present invention does not need to be configured with a complex reversing valve or designed with a complex reversing oil circuit.

[0031] 3. Because this invention has no complex reversing valve and no complex reversing oil circuit, its volume is smaller than that of a traditional impact cylinder of the same specification, and its processing is simple.

[0032] 4. Because the present invention has a closed pressurized energy storage process in both the impact deceleration stage and the return deceleration stage, in conjunction with the one-way valve and the oil storage structure, the initial acceleration is relatively high in both the impact acceleration stage and the return acceleration stage. Therefore, it has higher performance and higher frequency compared with traditional impact cylinders of the same specifications.

[0033] 5. This invention can adjust the performance without changing the size by adjusting the stroke (overall stroke of the impact cylinder, length of the piston rod impact oil inlet step), oil inlet position, oil outlet position, end area of ​​the first cavity and end area of ​​the second cavity, so as to meet the needs of different application scenarios and reduce the size and specifications of the product, which is conducive to standardization and serialization.

[0034] 6. In a preferred embodiment of the present invention, the uniformly distributed oil ports of the second cavity can effectively increase the stability of the piston rod operation and prevent the piston rod from running unstablely due to the oil continuously flowing out from the same direction during high-frequency operation.

[0035] 7. In a preferred embodiment of the present invention, the piston rod tail is fitted with the cylinder to limit the possible jumping of the piston rod, which can also effectively prevent the piston rod from deflecting and improve the impact stability. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0037] Figure 1 This is a cross-sectional view of the impact cylinder in Embodiment 1 of the present invention;

[0038] Figure 2 This is a cross-sectional view of the cylinder block in Embodiment 1 of the present invention;

[0039] Figure 3 This is a cross-sectional view of the piston rod in Embodiment 1 of the present invention;

[0040] Figure 4 This is a cross-sectional view of the impact cylinder at its initial position during the return acceleration phase in Embodiment 1 of the present invention;

[0041] Figure 5 This is a cross-sectional view of the impact cylinder at the end of the return acceleration phase in Embodiment 1 of the present invention;

[0042] Figure 6 This is a cross-sectional view of the impact cylinder at its initial position during the impact acceleration stage in Embodiment 1 of the present invention;

[0043] Figure 7 This is a cross-sectional view of the impact cylinder at the end of the impact acceleration stage in Embodiment 1 of the present invention;

[0044] Figure 8 This is a cross-sectional view of the impact cylinder at the end of the impact deceleration stage in Embodiment 1 of the present invention;

[0045] Figure 9 This is a cross-sectional view of the impact cylinder in Embodiment 2 of the present invention;

[0046] Figure 10 This is a cross-sectional view of the impact cylinder in Embodiment 3 of the present invention;

[0047] Figure 11A cross-sectional view of a first embodiment of the impact oil cylinder in Example 4 of the present application;

[0048] Figure 12 A cross-sectional view of a second embodiment of the impact oil cylinder in Example 4 of the present application;

[0049] Figure 13 A cross-sectional view of a third embodiment of the impact oil cylinder in Example 4 of the present application;

[0050] Figure 14 A cross-sectional view of a fourth embodiment of the impact oil cylinder in Example 4 of the present application

[0051] Figure 15 A cross-sectional view of an embodiment of the impact oil cylinder in Example 5 of the present application.

[0052] Reference signs:

[0053] Cylinder 1, oil inlet oil way 101, oil return oil way 102, first sliding cavity 103, second sliding cavity 104, second step structure 105, fourth step structure 106, oil leakage cavity 107, oil leakage hole 108, first oil way 109, second oil way 1010, third oil way 1011, fifth oil way 1012, sixth oil way 1013;

[0054] Piston rod 2, first rod body 201, second rod body 202, first step structure 203, third step structure 204, fourth oil way 205, groove 206, uniform oil port 207;

[0055] First cavity 3, second cavity 4, first oil storage structure 5, first one-way valve 6, second one-way valve 7, oil inlet step cavity 8, second oil storage structure 9, third oil storage structure 10, first overflow valve 11, second overflow valve 12.

[0056] The implementation, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0057] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the protection scope of the present application.

[0058] It should be noted that all the direction indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative position relationship, movement condition, etc. between components in a certain specific posture (as shown in the drawings), and if the specific posture changes, the direction indications will also change accordingly.

[0059] In addition, the descriptions such as "first", "second" and the like in the present application are only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first", "second" can be explicitly or implicitly included at least one of the features. In the description of the present application, the meaning of "a plurality of" is at least two, such as two, three, etc., unless otherwise specifically limited.

[0060] In the present application, unless otherwise specifically defined and limited, the terms "connection", "fixation" and the like should be understood in a broad sense, for example, "fixation" can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection, or physical connection or wireless communication connection; can be directly connected, or indirectly connected through intermediate medium, can be the internal communication of two elements or the interaction relationship of two elements, unless otherwise specifically limited. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0061] In addition, the technical solutions of each embodiment of the present application can be combined with each other, but it must be based on the fact that a person skilled in the art can realize it, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, nor is it within the scope of protection required by the present application.

[0062] Embodiment 1

[0063] As Figures 1-3 The differential pressure reversing impact oil cylinder disclosed in the present embodiment mainly comprises a cylinder body 1 and a piston rod 2, one end of the piston rod 2 is slidably connected in the cylinder body 1, and the other end is an impact end.

[0064] The piston rod 2 and the cylinder body 1 have a first cavity 3 and a second cavity 4, the first cavity 3 is located between the second cavity 4 and the impact end, the end area of the second cavity 4 is larger than that of the first cavity 3, and the volumes of the first cavity 3 and the second cavity 4 change reversely with the sliding of the piston rod 2, that is, during the sliding of the piston rod 2, either the volume of the first cavity 3 becomes larger and the volume of the second cavity 4 becomes smaller, or the volume of the first cavity 3 becomes smaller and the volume of the second cavity 4 becomes larger.

[0065] The cylinder 1 is provided with an oil inlet passage 101 and an oil return passage 102. The oil inlet passage 101 is in communication with the first cavity 3. The oil inlet passage 101 and the oil return passage 102 are in communication with the second cavity 4 in the sliding process of the piston rod 2. Specifically, one impact cycle of the impact cylinder can be divided into a return acceleration stage, a return deceleration stage, an impact acceleration stage and an impact deceleration stage according to the sliding process of the piston rod 2.

[0066] In the return acceleration stage, the oil inlet passage 101 is only in communication with the first cavity 3, and the oil return passage 102 is in communication with the second cavity 4. In this stage, the piston rod 2 is only accelerated by the oil pressure of the first cavity 3. In this stage, as the piston rod 2 retracts, the volume of the first cavity 3 gradually increases, and the volume of the second cavity 4 gradually decreases, until the second cavity 4 is in communication with the oil inlet passage 101 and the second cavity 4 is disconnected from the oil return passage 102, and then the return deceleration stage is entered.

[0067] In the return deceleration stage, the oil inlet passage 101 is in communication with the first cavity 3 and the second cavity 4, and the oil return passage 102 is disconnected from the second cavity 4. In this stage, the piston rod 2 is subjected to the oil pressure of the first cavity 3 and the second cavity 4 in opposite directions. Due to the inertia of the piston rod 2 in the return process, the piston rod 2 continues to move in the return direction until the second cavity 4 is filled with oil, and then the impact acceleration stage is entered.

[0068] In the impact acceleration stage, the oil inlet passage 101 is in communication with the first cavity 3 and the second cavity 4, and the oil return passage 102 is disconnected from the second cavity 4. At the beginning of this stage, since the second cavity 4 is filled with oil, the piston rod 2 no longer has the space to continue the return, so the speed is reduced to 0. In this stage, the piston rod 2 is subjected to the oil pressure of the first cavity 3 and the second cavity 4 in opposite directions, but since the end area of the second cavity 4 is larger than that of the first cavity 3, the oil pressure of the second cavity 4 is larger, so that the piston rod 2 slides in the opposite direction, that is, the impact stroke begins. In this stage, the volume of the first cavity 3 gradually decreases, and the volume of the second cavity 4 gradually increases, until the second cavity 4 is disconnected from the oil inlet passage 101 and the second cavity 4 is in communication with the oil return passage 102, and then the impact deceleration stage is entered.

[0069] In the impact deceleration stage, the oil inlet passage 101 is only in communication with the first cavity 3, and the oil return passage 102 is in communication with the second cavity 4. In this stage, the piston rod 2 is only subjected to the oil pressure of the first cavity 3, but due to the inertia, the piston rod 2 continues to perform the impact stroke until the speed is reduced to 0. At this time, the oil inlet passage 101 is only in communication with the first cavity 3, and the oil return passage 102 is in communication with the second cavity 4, which is the initial state of the return acceleration stage.

[0070] Thus, one impact cycle is completed, and the reciprocating impact of the impact cylinder is realized without complex reversing valves or reversing oil lines.

[0071] In the embodiment, the piston rod 2 comprises coaxial first rod body 201 and second rod body 202, and the first end of the second rod body 202 is connected with the first end of the first rod body 201, and the second end of the first rod body 201 is the impact end. The diameter / thickness of the second rod body 202 is smaller than that of the first rod body 201. The cylinder body 1 has coaxial first sliding cavity 103 and second sliding cavity 104, the first rod body 201 and the inner wall of the first sliding cavity 103 are in sliding fit, and the second rod body 202 and the inner wall of the second sliding cavity 104 are in sliding fit. By designing the two-stage sliding fit structure between the piston rod 2 and the cylinder body 1, the possible runout of the piston rod 2 can be effectively limited, and the piston rod 2 is also prevented from being deflected, so that the impact stability is improved.

[0072] The side wall of the first rod body 201 is provided with outward first step structure 203, and the inner wall of the cylinder body 1 is provided with inward second step structure 105, both the first step structure 203 and the second step structure 105 are annular structures, and the first cavity 3 is located between the first step structure 203 and the second step structure 105, and the first cavity 3 is an annular cavity. In the sliding process of the piston rod 2, the second step structure 105 remains stationary, while the first step structure 203 moves with the piston rod 2, so that the first step structure 203 and the second step structure 105 approach or move away from each other, so that the volume of the first cavity 3 changes.

[0073] The connection between the first rod body 201 and the second rod body 202 forms a third step structure 204, and the transition between the first sliding cavity 103 and the second sliding cavity 104 forms a fourth step structure 106. The third step structure 204 and the fourth step structure 106 are both annular structures. The second cavity 4 is located between the third step structure 204 and the fourth step structure 106, and the second cavity 4 is an annular cavity. During the sliding of the piston rod 2, the fourth step structure 106 remains stationary, while the third step structure 204 moves with the piston rod 2, causing the third step structure 204 and the fourth step structure 106 to move closer to or away from each other, thereby changing the volume of the second cavity 4. Further, the first step structure 203, the second step structure 105, the third step structure 204, and the fourth step structure 106 are sequentially and spacedly distributed. Since the first step structure 203 and the third step structure 204 are both fixedly arranged on the piston rod 2, i.e., the relative positions of the first step structure 203 and the third step structure 204 are fixed, when the first step structure 203 and the second step structure 105 move closer to each other, the third step structure 204 and the fourth step structure 106 must move away from each other. When the first step structure 203 and the second step structure 105 move away from each other, the third step structure 204 and the fourth step structure 106 must move closer to each other, thereby causing the volumes of the first cavity 3 and the second cavity 4 to change in opposite directions with the sliding of the piston rod 2.

[0074] As a preferred embodiment, an oil leakage cavity 107 is arranged between the second end of the second rod body 202 and the inner wall of the cylinder body 1, and an oil leakage hole 108 is arranged on the cylinder body 1 and communicates with the oil leakage cavity 107. The oil leakage cavity 107 is part of the second sliding cavity 104, i.e., during the design of the size, the length of the second sliding cavity 104 is designed to have a certain space surplus at the tail end as the oil leakage cavity 107, even if the piston rod 2 returns to the limit position.

[0075] In the embodiment, the impact oil cylinder further comprises a first oil storage structure 5, the cylinder body 1 is provided with a first oil channel 109 and a second oil channel 1010, one end of the first oil channel 109 is communicated with the oil inlet channel 101, and the other end is communicated with the first cavity 3. The first oil channel 109 is provided with a first one-way valve 6, the first end of the second oil channel 1010 is communicated with the first oil storage structure 5, the second end of the second oil channel 1010 is communicated with the first oil channel 109, and the communication position is located between the first one-way valve 6 and the first cavity 3. In the specific application process, the energy accumulator can be used as the first oil storage structure 5, and in the impact acceleration stage and the impact deceleration stage, the volume of the first cavity 3 is gradually reduced, and the first cavity 3 always maintains the state of being filled with oil. In this process, the first one-way valve 6 can effectively prevent the oil from flowing back to the oil inlet channel 101, and the first oil storage structure 5 can also play the roles of energy storage, oil storage and buffering. At the same time, in the return acceleration stage, the first oil storage structure 5 can release the stored oil and act on the oil inlet channel 101 at the same time, so that the piston rod 2 has a higher speed in the return acceleration stage.

[0076] In the embodiment, the cylinder body 1 is provided with a third oil channel 1011, the first end of the third oil channel 1011 is communicated with the oil inlet channel 101, and the second end is located on the inner wall of the cylinder body 1. The third oil channel 1011 is provided with a second one-way valve 7, so that the oil inlet channel 101 is communicated with the second cavity 4 in the return deceleration stage and the impact acceleration stage.

[0077] The second end of the third oil channel 1011 and the second cavity 4 are communicated or blocked by the piston rod 2 in the sliding process of the piston rod 2. Specifically, the piston rod 2 is provided with a fourth oil channel 205, and the first end and the second end of the fourth oil channel 205 are located on the outer wall of the piston rod 2. Among them, the first end of the fourth oil channel 205 is located on the side wall of the second rod body 202 and close to the position of the first rod body 201, and the second end of the fourth oil channel 205 is located on the outer wall of the first rod body 201 and between the second step structure 105 and the third step structure 204. Therefore, in the sliding process of the piston rod 2, when the second end of the fourth oil channel 205 and the second end of the third oil channel 1011 partially coincide or fully coincide, the oil inlet channel 101 is communicated with the second cavity 4; when the second end of the fourth oil channel 205 and the second end of the third oil channel 1011 are staggered, the oil inlet channel 101 and the second cavity 4 are blocked.

[0078] As a preferred embodiment, the position corresponding to the second end of the fourth oil channel 205 on the piston rod 2 is provided with a recess 206 of an annular structure, the recess 206 and the inner wall of the cylinder body 1 form an annular oil inlet step cavity 8, and the second end of the fourth oil channel 205 is located at the bottom of the recess 206, so as to effectively avoid the circumferential rolling of the piston rod 2 in the impact process, so that the second end of the fourth oil channel 205 and the second end of the third oil channel 1011 cannot coincide.

[0079] As a preferred embodiment, the fourth oil path 205 has a plurality of first ends, each of which is annularly and evenly distributed on the side wall of the second rod body 202 as an oil distribution port 207, so as to increase the running stability of the piston rod 2 and prevent the piston rod 2 from running unstably due to the oil being discharged from the same direction during high-frequency operation.

[0080] In the embodiment, the impact oil cylinder further comprises a second oil storage structure 9, and the cylinder body 1 is provided with a fifth oil path 1012, one end of the fifth oil path 1012 being in communication with the second oil storage structure 9 and the other end being in communication with the second cavity 4. In specific applications, an accumulator can be used as the second oil storage structure 9, and the second oil storage structure 9 also plays the roles of energy storage, oil storage and buffering. Specifically, during the return deceleration stage, since the oil inlet path 101 is in communication with both the first cavity 3 and the second cavity 4 and the oil return path 102 is disconnected from the second cavity 4, when the second cavity 4 is filled with oil, the oil in the second cavity 4 can only flow to the second oil storage structure 9 and compress the second oil storage structure 9, and at this time, the second oil storage structure 9 simultaneously applies a counterforce to the second cavity 4, which can further improve the deceleration effect of the piston rod 2 during the return deceleration stage under the action of the counterforce and the oil inlet pressure of the second cavity 4. Meanwhile, the counterforce of the second oil storage structure 9 to the second cavity 4 also acts on the acceleration process of the piston rod 2 during the impact acceleration stage, so that the piston rod 2 has a higher speed during the impact acceleration stage.

[0081] In the embodiment, the impact oil cylinder further comprises a third oil storage structure 10, and the cylinder body 1 is provided with a sixth oil path 1013, one end of the sixth oil path 1013 being in communication with the third oil storage structure 10 and the other end of the sixth oil path 1013 being located on the inner wall of the cylinder body 1 and being in communication with or being disconnected from the first cavity 3 during the sliding process of the piston rod 2. That is, during the sliding process of the piston rod 2, when the first end of the sixth oil path 1013 is located between the first step structure 203 and the second step structure 105, the first end of the sixth oil path 1013 is in communication with the first cavity 3, otherwise it is disconnected. In specific applications, an accumulator can be used as the third oil storage structure 10, and during the impact deceleration stage, the volume of the first cavity 3 is gradually reduced and the first cavity 3 is always filled with oil, and during this process, the oil return from the oil inlet path 101 can be effectively avoided through the first one-way valve 6, and the first oil storage structure 5 and the third oil storage structure 10 jointly play the roles of energy storage, oil storage and buffering. Meanwhile, during the return acceleration stage, the first oil storage structure 5 and the third oil storage structure 10 can release the stored oil and act on the oil inlet path 101 at the same time, so that the piston rod 2 has a higher speed during the return acceleration stage.

[0082] The principle of the impact oil cylinder in the embodiment is further described below in combination with specific legends.

[0083] Reference is made to Figure 4 At this time, the impact oil cylinder is in the initial position, and the oil inlet route is the oil inlet oil route 101→the first oil route 109→the first cavity 3, the oil outlet route is the second cavity 4→the oil return oil route 102, and the process is the return stroke acceleration stage.

[0084] Reference is made to Figure 5 At this time, the impact oil cylinder is in the initial position, and the oil inlet route is the oil inlet oil route 101→the first oil route 109→the first cavity 3, the oil outlet route is the second cavity 4→the oil return oil route 102, and the process is the return stroke acceleration stage.

[0085] Because the end area of the second cavity 4 is larger than that of the first cavity 3, the force of the second cavity 4 is greater than that of the first cavity 3, so the piston rod 2 is subjected to a leftward force; at the same time, the oil return oil route 102 is closed, and the oil in the second cavity 4 can only flow to the second oil storage structure 9, compressing the diaphragm of the second oil storage structure 9, at this time, the second oil storage structure 9 and the second oil inlet route simultaneously apply a counterforce to the second cavity 4, and under the action of the two forces, the piston rod 2 starts to decelerate, and the process is the return stroke deceleration stage.

[0086] In this return stroke deceleration stage, the second oil storage structure 9 has three main functions: energy storage, oil storage, and buffering. Because the reversing valve is not used for reversing, the oil route switching is only whether the second cavity 4 is connected with the oil inlet oil route 101 and the oil return oil route 102. Therefore, the impact needs to accumulate enough potential energy to ensure the impact effect, and in the return stroke deceleration process, because the second one-way valve 7 exists, the second cavity 4 is connected with the oil inlet oil route 101 in one direction, and all the oil discharged from the second cavity 4 can only be stored by the second oil storage structure 9, at this time, the pressure in the second cavity 4 is gradually higher than the pressure in the first cavity 3 and the oil inlet pressure, realizing oil storage and energy storage to ensure that the potential energy is sufficient for impact acceleration.

[0087] Reference is made to Figure 6At this time, the oil cylinder is the impact starting position, and the impact piston speed is zero at this position. At this time, the first oil inlet line is the oil inlet oil path 101→the first oil path 109→the first cavity 3, and the second oil inlet line is the oil inlet oil path 101→the third oil path 1011→the fourth oil path 205→the second cavity 4. Meanwhile, the oil return oil path 2 is closed, and the second oil storage structure 9 is compressed to the maximum value. Under the action of the two forces, i.e., the force applied to the piston rod 2 by the second cavity 4 and the reaction force applied to the second cavity 4 by the second oil storage structure 9, the piston rod 2 starts to accelerate to the left. This process is the impact acceleration stage.

[0088] At this time, the impact acceleration stage is due to the accumulated pressure of the return deceleration stage and the action of the second one-way valve 7. The pressure in the second cavity 4 is higher than the oil inlet pressure and the pressure in the first cavity 3. Therefore, the impact oil cylinder has higher impact acceleration and stronger impact performance than the same specification impact oil cylinder.

[0089] Reference Figure 7 At the intermediate position to the left, the piston rod 2 is suddenly reduced to 0 due to the communication between the second cavity 4 and the oil return oil path 102. The force of the first cavity 3 on the left side of the piston rod 2 remains unchanged, and the piston rod 2 starts to impact deceleration. At this time, the first oil storage structure 5 and the third oil storage structure 10 play a buffering role. When running to Figure 8 the position, the first one-way valve 6 starts to act, and the oil inlet oil path 101 is connected to the first cavity 3 in one direction. At this time, the first oil storage structure 5 plays a role in energy storage, oil storage, and buffering. Due to the accumulated pressure of the impact deceleration stage and the action of the first one-way valve 6, the pressure in the first cavity 3 is gradually higher than the oil inlet pressure, and the first oil storage structure 5 accumulates a large potential energy. Therefore, the impact acceleration is stronger than the same specification impact oil cylinder. Figure 8 After running to Figure 4 the position, the return acceleration stage is under the action of the first oil storage structure 5 and the pressure difference. Therefore, the return acceleration is also higher than that of the same specification impact oil cylinder. Therefore, the overall impact oil cylinder frequency is also higher than that of the same specification impact oil cylinder, thereby improving the impact efficiency.

[0090] In summary, the entire cycle is an entire impact cycle. The impact reversing does not rely on a reversing valve, and a large number of reversing oil paths are not designed to improve the processing difficulty. On the basis of simpler structure and lower processing difficulty, the performance is stronger, the frequency is higher, and the impact efficiency is higher. Figures 4 to 8 Embodiment 2

[0091] As shown in

[0092] the embodiment, a differential pressure reversing impact oil cylinder is disclosed. The implementation manner of the embodiment is basically the same as that of embodiment 1, and the difference is only that: Figure 9

[0093] ​The first and second oil storage structures 5 and 9 are provided with overflow mechanisms to prevent damage to hydraulic elements caused by excessive pressure. Specifically, a first overflow valve 11 is arranged on the first connecting pipeline between the first oil storage structure 5 and the second oil passage 1010, and a second overflow valve 12 is arranged on the connecting pipeline between the second oil storage structure 9 and the fifth oil passage 1012. The working principle of the impact cylinder in this embodiment is the same as that in Embodiment 1, and thus will not be described again.

[0094] Embodiment 3

[0095] As Figure 10 shown in FIG. 6, the impact cylinder disclosed in this embodiment is a differential pressure reversing impact cylinder, and its implementation is basically the same as that in Embodiment 1, except that:

[0096] In this embodiment, the piston rod 2 is a straight rod structure, i.e., the first cavity 3 is located between the side wall of the piston rod 2 and the inner wall of the cylinder body 1, the second cavity 4 is located between the end wall of the piston rod 2 and the inner wall of the cylinder body 1, the first end of the fourth oil passage 205 is located on the side wall of the piston rod 2, and the second end of the fourth oil passage 205 is located on the end wall of the piston rod 2. In this embodiment, the oil drain chamber and the oil drain hole are no longer arranged to optimize the size structure of the impact cylinder. The working principle of the impact cylinder in this embodiment is the same as that in Embodiment 1, and thus will not be described again.

[0097] Embodiment 4

[0098] As Figure 11 shown in FIG. 6, the impact cylinder disclosed in this embodiment is a differential pressure reversing impact cylinder, and its implementation is basically the same as that in Embodiment 1, except that:

[0099] In this embodiment, the third oil storage structure 10 is cancelled. Although the cancellation of the third oil storage structure 10 has an impact on the deceleration effect, it does not affect the principle. The working principle of the impact cylinder in this embodiment is the same as that in Embodiment 1, and thus will not be described again.

[0100] It is worth noting that in the specific application process, the first and / or second oil storage structures 5 and 9 can also be cancelled, i.e., Figures 12 to 14 as shown in FIG. 6.

[0101] Embodiment 5

[0102] The impact cylinder disclosed in this embodiment is a differential pressure reversing impact cylinder, and its implementation is basically the same as that in Embodiment 1, except that two or three of the three schemes in Embodiments 2 to 4 are combined, for example, Figure 15 as shown in FIG. 6.

[0103] The above merely describes the preferred embodiments of the present application, and is not intended to limit the patent scope of the present application. Any equivalent structural changes made according to the content of the present application specification and drawings, or direct / indirect application in other related technical fields, are included in the patent protection scope of the present application.

Claims

1. A pressure differential reversing impact cylinder, comprising a cylinder body and a piston rod, one end of the piston rod being slidably connected in the cylinder body and the other end being an impact end; characterized in that a first cavity and a second cavity being provided between the piston rod and the cylinder body, the first cavity being located between the second cavity and the impact end, the end area of the second cavity being larger than that of the first cavity, and the volume of the first cavity and the second cavity changing reversely with the sliding of the piston rod; an oil inlet passage and an oil return passage being provided on the cylinder body, the oil inlet passage being in communication with the first cavity, the oil inlet passage and the oil return passage being in communication with the second cavity alternately during the sliding of the piston rod; a third oil passage being provided in the cylinder body, a first end of the third oil passage being in communication with the oil inlet passage, and a second end of the third oil passage being located on the inner wall of the cylinder body; a fourth oil passage being provided on the piston rod, a first end of the fourth oil passage being in communication with the second cavity, and a second end of the fourth oil passage being in communication with or being blocked by the second end of the third oil passage during the sliding of the piston rod.

2. The pressure differential reversing impact ram as set forth in claim 1, wherein, a first oil passage being provided in the cylinder body, one end of the first oil passage being in communication with the oil inlet passage, and the other end of the first oil passage being in communication with the first cavity.

3. The pressure differential reversing impact ram as set forth in claim 2, wherein, a first oil storage structure being further included, a second oil passage being provided in the cylinder body, a first end of the second oil passage being in communication with the first oil storage structure; a first check valve being provided on the first oil passage, a second end of the second oil passage being in communication with the first oil passage, and the communication being located between the first check valve and the first cavity.

4. The pressure differential reversing impact ram as set forth in claim 3, wherein, a first overflow valve being provided on the first connecting pipeline between the first oil storage structure and the second oil passage.

5. The pressure differential reversing impact ram as set forth in claim 1, wherein, a second check valve being provided on the third oil passage.

6. A pressure differential reversing impact ram as claimed in any one of claims 1 to 5, characterised in that, the piston rod is a straight rod structure; the first cavity is located between the side wall of the piston rod and the inner wall of the cylinder body, and the second cavity is located between the end wall of the piston rod and the inner wall of the cylinder body; the first end of the fourth oil passage is located on the side wall of the piston rod, and the second end of the fourth oil passage is located on the end wall of the piston rod.

7. A pressure differential reversing impact ram as claimed in any one of claims 1 to 5 wherein, the piston rod comprises a coaxial first rod body and a second rod body, and a first end of the second rod body is connected with a first end of the first rod body, and a second end of the first rod body is the impact end; the first cavity is located between the side wall of the first rod body and the inner wall of the cylinder body, and the second cavity is located between the side wall of the second rod body and the inner wall of the cylinder body; the first end of the fourth oil passage is located on the side wall of the first rod body, and the second end of the fourth oil passage is located on the side wall of the second rod body.

8. A pressure differential reversing impact ram as claimed in claim 7, wherein, the fourth oil passage has a plurality of first ends, and each first end of the fourth oil passage is annularly and uniformly distributed on the side wall of the second rod body.

9. The pressure differential reversing impact ram as set forth in claim 7, wherein, a drain cavity is provided between the second end of the second rod body and the inner wall of the cylinder body, and a drain hole in communication with the drain cavity is provided on the cylinder body.

10. A pressure differential reversing impact ram as claimed in any one of claims 1 to 5, characterised in that, a second oil storage structure is further included, a fifth oil passage is provided in the cylinder body, one end of the fifth oil passage is in communication with the second oil storage structure, and the other end of the fifth oil passage is in communication with the second cavity.

11. A pressure differential reversing impact ram as claimed in claim 10, wherein, a second overflow valve is provided on the connecting pipeline between the second oil storage structure and the fifth oil passage.

12. A pressure differential reversing impact ram as claimed in any one of claims 1 to 5 wherein, The third oil storage structure is further included, the sixth oil path is arranged in the cylinder body, and a first end of the sixth oil path is communicated with the third oil storage structure; A second end of the sixth oil path is located on an inner wall of the cylinder body, and the second end of the sixth oil path is communicated with or blocked by the piston rod in the sliding process of the piston rod.

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