Electric hydraulic tool capable of quickly returning oil and resetting

Abstract

The utility model discloses an electric hydraulic tool capable of quickly returning oil and resetting, which comprises a hydraulic pump and an oil bag, the hydraulic pump comprises a pump body, a piston cavity is arranged in the pump body, and a piston is arranged in the piston cavity; an oil inlet passage and an oil return passage which are not communicated with each other are arranged between the piston cavity and the oil bag; the whole piston cavity is divided into a front oil return cavity and a rear working cavity by the piston, and the rear working cavity is communicated with the oil inlet passage and the oil return passage; an independently-arranged quick oil return passage is further arranged in the pump body, the rear end of the quick oil return passage is directly communicated with the oil bag, and the front end of the quick oil return passage is communicated with the front end of the front oil return cavity; and a quick oil return valve is arranged on the piston. According to the electric hydraulic tool capable of rapidly returning oil and resetting, when the piston moves forwards to a set distance, the oil return valve can be automatically clamped to conduct rapid oil return operation, the oil return idle stroke time of the electric hydraulic tool can be effectively shortened, and the working efficiency of the hydraulic tool is improved.

Description

Technical Field

[0001] The present invention relates to an electro-hydraulic tool, specifically an electro-hydraulic tool capable of quickly returning oil and resetting. Background Art

[0002] In factory production, engineering construction or home decoration, electro-hydraulic tools are often used. Here, Patent CN111469098A discloses a power structure of an all-round electro-hydraulic tool, and specifically discloses a hydraulic pump, an oil bag, a driving motor, a battery and a control circuit board; the hydraulic pump includes a pump body, a piston chamber is arranged in the first half of the pump body, a piston is installed in the piston chamber, and a piston rod of the piston extends out from the top end of the pump body and is connected to a working jaw assembly; an oil inlet passage and an oil return passage that are not communicated with each other are arranged between the piston chamber and the oil bag; an oil inlet device for pressurizing and sending low-pressure oil in the oil bag to the piston chamber is arranged on the oil inlet passage; a pressure relief device that is opened when the oil pressure in the piston chamber exceeds a set value is arranged on the oil return passage; in the above structure, when the piston moves forward to push the jaw assembly to complete the work, the oil return operation can only be carried out by continuously feeding oil to open the safety valve in the pressure relief device, and the aperture of the pressure relief hole of the safety valve of the pressure relief device is only about 0.9 mm, which results in a very slow oil return speed, and the entire oil return process takes about more than 10 seconds, which will seriously affect the working efficiency of the hydraulic tool. Summary of the Invention

[0003] Aiming at the above problems, the present invention designs an electro-hydraulic tool capable of quickly returning oil and resetting. When the piston moves forward to a set distance, the oil return valve can be automatically unlocked for quick oil return operation, realizing oil return in 1 second, which can effectively shorten the oil return idle stroke time of the electro-hydraulic tool and improve the operation efficiency of the hydraulic tool.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] An electric hydraulic tool capable of quickly returning oil and resetting, comprising a hydraulic pump and an oil bag. The hydraulic pump includes a pump body, a piston chamber is arranged in the pump body, a piston is installed in the piston chamber, a return spring is arranged between the piston and the front end of the piston chamber, and the piston rod of the piston extends out from the top of the pump body and is connected to a clamping head assembly for work; an oil inlet passage and an oil return passage that are not communicated with each other are arranged between the piston chamber and the oil bag. An oil inlet device for pressurizing and sending low-pressure oil in the oil bag to the piston chamber is arranged on the oil inlet passage, and a pressure relief device that opens when the oil pressure in the piston chamber exceeds a set value is arranged on the oil return passage. It is characterized in that: the piston divides the entire piston chamber into a front oil return chamber and a rear working chamber, and the rear working chamber communicates with the oil inlet passage and the oil return passage; a fast oil return passage with an independent layout is also arranged in the pump body, the rear end of the fast oil return passage is directly connected to the oil bag, and the front end of the fast oil return passage is communicated with the front end of the front oil return chamber; a fast oil return valve is arranged on the piston. During work, the fast oil return valve is normally closed. When the piston moves forward to a set position, the fast oil return valve opens, so that the rear working chamber is communicated with the front oil return chamber for fast oil return operation, and when the piston moves backward to the initial position, the fast oil return valve closes.

[0006] More specifically, the above-mentioned fast oil return valve includes a mounting hole arranged on the piston. A plurality of oil return holes communicating the rear working chamber and the front oil return chamber are arranged along the circumferential direction around the mounting hole. A push rod that can move back and forth is arranged in the mounting hole. The rear end of the push rod extends into the rear working chamber and is connected to a valve flap. An oil return valve spring is arranged on the neck of the push rod. The oil return valve spring has an initial compression amount so that the push rod always has a certain tendency to move backward. In the initial state, the piston is held against the rear end face of the rear working chamber under the action of the return spring, so that the valve flap seals each of the oil return holes. The front end of the push rod extends out and extends forward for a part; at the same time, a stop bushing is arranged on the front side of the front oil return chamber of the pump body. When the piston rod moves forward to the set position, the push rod is held against the stop bushing, so that the valve flap overcomes the high-pressure oil pressure and opens for fast oil return operation.

[0007] More specifically, an oil inlet groove is arranged at the position of the oil return hole on the side of the rear working chamber of the piston.

[0008] More specifically, a pre-stored oil groove is arranged behind the rear working chamber of the pump body.

[0009] More specifically, a buffer spring is arranged at the front end of the push rod.

[0010] More specifically, a driving device is arranged on the side of the pump body at the position of the oil inlet device.

[0011] The electric hydraulic tool capable of rapid oil return and reset designed by the present invention has a separate rapid oil return passage designed on its pump body in addition to the original oil inlet passage and oil return passage, and a rapid oil return valve is provided on the piston. In the initial state or during the pressurization process, the rapid oil return valve is in a normally closed state, at which time the rear working chamber and the front oil return chamber are not connected. This process continues until the piston moves forward to a set position, at which time the rapid oil return valve opens to connect the rear working chamber and the front oil return chamber to perform a rapid oil return operation. The entire oil return pressure relief process only takes about 1 second. Compared with the existing structure for pressure relief through a safety valve of a pressure relief device, it can reduce the idle time of the oil return exponentially, thereby effectively improving the working efficiency of the hydraulic tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 , a schematic diagram of the three-dimensional structure of the present invention;

[0013] Figure 2 , a cross-sectional view of the present invention;

[0014] Figure 3 The present invention Figure 2 A partial enlarged schematic diagram of the middle A part;

[0015] Figure 4 , a schematic diagram of the three-dimensional structure of the oil circuit in the pump body of the present invention;

[0016] Figure 5 , a schematic diagram of the three-dimensional structure of the piston, piston rod and return spring of the present invention;

[0017] in,

[0018] 1—hydraulic pump, 11—pump body, 111—piston chamber, 111a—front oil return chamber, 111b—rear working chamber, 111b1—pre-storage oil groove, 112—stop bushing, 12—piston, 121—piston rod, 13—return spring, 14—oil inlet passage, 141—oil inlet device, 142—driving device, 15—oil return passage, 151—pressure relief device, 16—rapid oil return passage;

[0019] 2—Oil bag;

[0020] 3—Clamp head assembly;

[0021] 4—quick oil return valve, 41—mounting hole, 42—oil return hole, 421—oil inlet groove, 43—top rod, 431—buffer spring, 44—valve disc, 45—oil return valve spring. DETAILED DESCRIPTION

[0022] like Figures 1-5 As shown, an electric hydraulic tool capable of rapid oil return and resetting comprises a hydraulic pump 1 and an oil bag 2.

[0023] The hydraulic pump 1 includes a pump body 11. A piston chamber 111 is provided in the pump body 11. A piston 12 is installed in the piston chamber 111. A return spring 13 is provided between the piston 12 and the front end of the piston chamber 111. In the initial state, the return spring 13 has a pre-compression amount so that the piston 12 always has a tendency to move backward, which is used for the piston 12 to move backward and reset during the oil return process. The piston rod 121 of the piston 12 extends out from the top of the pump body 1 and is connected to the clamping head assembly 3 for work.

[0024] An oil inlet passage 14 and an oil return passage 15 that do not communicate with each other are provided between the piston chamber 111 and the oil bag 2. An oil inlet device 141 for pressurizing and sending the low-pressure oil in the oil bag 2 to the piston chamber 111 is provided on the oil inlet passage 14. A pressure relief device 151 that opens when the oil pressure in the piston chamber 111 exceeds a set value is provided on the oil return passage 15.

[0025] The piston 12 divides the entire piston chamber 111 into a front oil return chamber 111a and a rear working chamber 111b. The rear working chamber 111b communicates with the oil inlet passage 14 and the oil return passage 15. An independent layout of a rapid oil return passage 16 is also provided in the pump body 1. The rear end of the rapid oil return passage 16 is directly connected to the oil bag 2, and the front end of the rapid oil return passage 16 is communicated with the front end of the front oil return chamber 111a.

[0026] A rapid oil return valve 4 is provided on the piston 12. In the initial state and during the pressurization process, the rapid oil return valve 4 is in a normally closed state. When the piston 12 moves forward to a set position, the rapid oil return valve 4 opens to make the rear working chamber 111b communicate with the front oil return chamber 111a for rapid oil return operation, and when the piston 12 moves backward to the initial position, the rapid oil return valve 4 closes again. Here, the structure of the rapid oil return valve 4 can be various. It can be a mechanical valve or an electromagnetic valve, as long as it has the function of opening after the piston 12 moves in place and closing after moving backward and resetting. It is selected according to actual needs in practice.

[0027] In this illustration, only the structure of the mechanical valve will be described. The rapid oil return valve 4 includes a mounting hole 41 provided on the piston 12. A plurality of oil return holes 42 communicating the rear working chamber 111b and the front oil return chamber 111a are provided along the circumferential direction around the mounting hole 41. A push rod 43 that can move back and forth is provided in the mounting hole 41. The rear end of the push rod 43 extends into the rear working chamber 111b and is connected to a valve flap 44. A return valve spring 45 is provided on the neck of the push rod 43. The return valve spring 45 has an initial compression amount so that the push rod 43 always has a certain tendency to move backward. The front end of the push rod 43 extends out and extends forward for a part. At the same time, a stop bushing 112 for stopping the forward movement of the push rod 43 is provided on the front side of the front oil return chamber 111a of the pump body 1.

[0028] In the initial state without pressure, since the piston 12 moves backward under the action of the return spring 13 and abuts against the rear end face of the rear working chamber 111b, it will drive the valve flap 44 to move forward together to seal each of the oil return holes 42, so that the rear working chamber 111b and the front oil return chamber 111a are not communicated, to ensure the normal oil inlet operation of the rear working chamber 111.

[0029] When starting to pressurize, the high-pressure oil entering the rear working chamber 111b will squeeze the rear end face of the valve flap 44. At this time, the squeezing force received by the valve flap 44 is much greater than the return force of the oil return valve spring 45, and the valve flap 44 still tightly adheres to the piston 12 to seal the oil return hole 42. This process continues until the piston 12 moves forward to the set position, that is, the front clamp head assembly completes the corresponding operation. At this time, the front end of the ejector rod 43 will touch the stop bushing 112. Affected by the reaction force of the stop bushing 112, the ejector rod 43 will drive the valve flap 44 to move backward relative to the piston 12 against the high-pressure oil pressure to open the quick oil return valve 4. At this time, quick oil return operation is carried out through multiple oil return holes 42. During this process, the valve flap 44 enters the high-pressure oil, so that the hydraulic force acting on it disappears, and it always moves backward under the action of only the return force of the oil return valve spring 45 to maintain the open state. Since multiple oil return holes 42 carry out oil return operation simultaneously, the entire oil return process can be completed in about 1 second.

[0030] When the oil return is completed, the piston 12 moves forward again under the action of the return spring 13 and abuts against the rear end face of the rear working chamber 111b. It will drive the valve flap 44 to move forward together to seal each of the oil return holes 42 again, so that the rear working chamber 111b and the front oil return chamber 111a are truncated again, to prepare for the next oil inlet.

[0031] In summary, for the electro-hydraulic tool with the above structure that can quickly return oil and reset, in addition to the original oil inlet passage 14 and oil return passage 15 on the pump body 1, a separate quick oil return passage 16 is designed, and a quick oil return valve 4 is provided on the piston 12. In the initial state or during the pressurization process, the quick oil return valve 4 is in the normally closed state. At this time, the rear working chamber 111b and the front oil return chamber 111a are not communicated, which can ensure normal pressurization operation. This process continues until the piston 12 moves forward to the set position. At this time, the quick oil return valve 4 is opened, so that the rear working chamber 111b is communicated with the front oil return chamber 111a to carry out quick oil return operation. The entire oil return and pressure relief process only takes about 1 second. Compared with the existing structure that uses a pressure relief device, the safety valve, for oil return and pressure relief, it can multiply reduce the dead travel time of oil return, and thus can effectively improve the working efficiency of the hydraulic tool.

[0032] A buffer spring 431 is provided at the front end of the ejector rod 43, which can effectively buffer the rigid impact when the ejector rod 43 abuts against the stop bushing 112, so as to effectively extend the service life of the ejector rod 43.

[0033] Here, to further improve the oil return speed of the quick oil return valve 4, an oil inlet groove 121 is provided at the position of the oil return hole 42 on the rear working chamber side of the piston 12, so that once the valve flap 44 is opened, large-flow oil return and pressure relief can be carried out.

[0034] Furthermore, to ensure the effective operation of the piston 12, a pre-stored oil groove 111b1 is provided behind the rear working chamber 111b of the pump body 1, and the inlet of the oil inlet passage 14 is arranged at the bottom of the pre-stored oil groove 111b1. This structural arrangement ensures that a certain amount of hydraulic oil is always stored in the rear working chamber 111b to prevent the hydraulic oil in the rear working chamber 111b from being too little at the start of pressurization to generate sufficient hydraulic pressure to push the piston forward.

[0035] A driving device 142 is provided at the position of the oil inlet device 141 on the side of the pump body 1, and a lithium battery for supplying power to the driving device is provided below the driving device 142.

[0036] The above is only the preferred embodiment of the present invention, and does not impose any form of limitation on the invention. Any simple modification, equivalent change or modification made to the above embodiments based on the technical principle of the present invention still falls within the scope of the technical solution of the present invention.

Claims

1. An electric hydraulic tool capable of rapid oil return and reset, comprising a hydraulic pump (1) and an oil bag (2), wherein the hydraulic pump (1) comprises a pump body (11), wherein a piston chamber (111) is provided in the pump body (11), wherein a piston (12) is installed in the piston chamber (111), wherein a reset spring (13) is provided between the piston (12) and the front end of the piston chamber (111), wherein a piston rod (121) of the piston (12) extends from the top end of the pump body (11) and is connected to a working pliers assembly (3); wherein an oil inlet passage (14) and an oil return passage (15) which are not connected to each other are provided between the piston chamber (111) and the oil bag (2), wherein an oil inlet device (141) is provided on the oil inlet passage (14) for pressurizing low-pressure oil in the oil bag (2) and sending it to the piston chamber (111), wherein a pressure relief device (151) is provided on the oil return passage (15) which is opened when the oil pressure in the piston chamber (111) exceeds a set value, wherein: The piston (12) divides the entire piston chamber (111) into a front oil return chamber (111a) and a rear working chamber (111b), wherein the rear working chamber (111b) is connected to the oil inlet passage (14) and the oil return passage (15); the pump body (11) is also provided with an independently arranged quick oil return passage (16), wherein the rear end of the quick oil return passage (16) is directly connected to the oil bag (2), and the front end of the quick oil return passage (16) is connected to the front end of the front oil return chamber (111a); a quick oil return valve (4) is provided on the piston (12), wherein the quick oil return valve (4) is in a normally closed state during operation; when the piston (12) moves forward to a set position, the quick oil return valve (4) opens to connect the rear working chamber (111b) to the front oil return chamber (111a) to perform a quick oil return operation; and when the piston (12) moves backward to an initial position, the quick oil return valve (4) closes.

2. An electric hydraulic tool capable of rapid oil return and reset as claimed in claim 1, characterized in that: The quick oil return valve (4) comprises a mounting hole (41) provided on the piston (12); a plurality of oil return holes (42) are provided around the mounting hole (41) along the circumferential direction and are connected to the rear working chamber (111b) and the front oil return chamber (111a); a push rod (43) that can move forward and backward is provided in the mounting hole (41); the rear end of the push rod (43) extends into the rear working chamber (111b) and is connected to a valve flap (44); an oil return valve spring (45) is provided on the neck of the push rod (43); the oil return valve spring (45) has an initial compression amount so that the push rod (43) always has a certain In the initial state, the piston (12) is supported on the rear end surface of the rear working chamber (111b) by the action of the return spring (13), so that the valve flap (44) seals each of the oil return holes (42), and the front end of the push rod (43) extends out and extends forward a part; at the same time, the pump body (11) is provided with a stop bushing (112) on the front side of the front oil return chamber (111a), and when the piston rod (121) moves forward to a set position, the push rod (43) is supported on the stop bushing (112), so that the valve flap (44) overcomes the high-pressure oil pressure and opens to perform a rapid oil return operation.

3. An electric hydraulic tool capable of rapid oil return and reset as claimed in claim 2, characterized in that: The piston (12) is provided with an oil inlet groove (421) at the position of the oil return hole (42) on the rear working chamber (111b) side.

4. An electric hydraulic tool capable of rapid oil return and reset as claimed in any one of claims 1 to 3, characterized in that: The pump body (11) is provided with a pre-storage oil groove (111b1) behind the rear working chamber (111b).

5. An electric hydraulic tool capable of rapid oil return and reset as claimed in claim 2 or 3, characterized in that: A buffer spring (431) is provided at the front end of the push rod (43).

6. An electric hydraulic tool capable of rapid oil return and reset as claimed in any one of claims 1 to 3, characterized in that: A driving device (142) is provided on the side of the pump body (11) at the position of the oil inlet device (141).

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