Hydraulic tools

Abstract

The present invention provides a hydraulic tool, which includes a driving device and a hydraulic component. The hydraulic component includes: a body extending in a longitudinal direction; a piston pump including a pump chamber and a piston reciprocating in the pump chamber; a hydraulic cylinder including a hydraulic chamber and a piston reciprocating in the hydraulic chamber; the pump chamber and the hydraulic chamber are defined in the body, arranged in series along the longitudinal direction and in fluid communication; and a hydraulic fluid storage device for supplying hydraulic fluid to the pump chamber. Wherein, the driving device is arranged in a direction intersecting with the longitudinal direction, the hydraulic fluid storage device is arranged on a longitudinal section of the outer surface of the body, and the hydraulic fluid storage device extends along the longitudinal direction to cover the longitudinal range of the longitudinal section and extends along the circumferential direction of the body to cover at least a part of the 360-degree circumferential range of the longitudinal section, so that the hydraulic fluid storage device and the outer surface it covers together define a volume for accommodating hydraulic fluid.

Description

Technical Field

[0001] The present application relates to a hydraulic tool, and particularly to a hydraulic tool having an L-shaped arrangement. Background Art

[0002] Hydraulic tools are commonly used driving devices in the industrial field, which can be connected to various different tool heads to perform corresponding industrial operations, such as crimping, flanging, shearing, punching operations, etc. Existing hydraulic tools are usually in an inline arrangement, that is, the hydraulic oil tank, the driving device, the pump device, the hydraulic cylinder and related components are arranged in sequence along the longitudinal direction, which makes the longitudinal dimension of the hydraulic tool larger, and thus is not conducive to operating in a space-limited area. In addition, since the hydraulic oil tank is arranged at the rearmost part of the hydraulic tool, the components of the driving device have to be immersed in the hydraulic oil, thereby shortening the service life of the driving device.

[0003] In order to release the pressure when the operation ends or the hydraulic pressure in the hydraulic cylinder reaches a certain threshold, a pressure relief valve is usually provided in the hydraulic tool. In the existing design, the pressure relief valve is usually arranged transversely to the longitudinal direction of the hydraulic tool, which in turn increases the lateral dimension of the hydraulic tool to a certain extent, which is also undesirable.

[0004] In addition, due to easy wear, the cylinder body where the hydraulic cylinder piston is located needs to be maintained or replaced regularly. However, since the cylinder body of the hydraulic cylinder is relatively bulky, and even the cylinder body may be an integral body of the entire hydraulic tool, the maintenance or replacement work is difficult and costly.

[0005] Hydraulic tools usually have a separate working head for connecting to the tool head and then manipulating the tool head. Conventional working heads are made of bar stock or forged steel materials by machining means. Due to the structure of the working head, a large amount of machining is required, which increases the cost to a certain extent.

[0006] Therefore, there is a need for a hydraulic tool with a compact structure and a small longitudinal dimension to be suitable for operating in a space-limited situation. At the same time, there is a need for a hydraulic tool improved in the above aspects.

[0007] It should be noted that this background art section is intended to illustrate the technical background of the present application and is not intended to limit the scope of the present application. It should also be pointed out that the technical content provided in this section is intended to help those skilled in the art understand the present invention and does not necessarily constitute prior art. Summary of the Invention

[0008] In this section, a general overview of the present invention is provided, rather than a full disclosure of the entire scope of the present invention or all features of the present invention.

[0009] The object of the present invention is to provide a hydraulic tool with a compact structure and reduced longitudinal dimensions.

[0010] Another object of the present invention is to provide a hydraulic tool that is easy to install and maintain and has a lower cost.

[0011] A further object of the present invention is to provide a hydraulic tool that is easier to manufacture.

[0012] According to one aspect of the present invention, there is provided a hydraulic tool, the hydraulic tool comprising:

[0013] a driving device; and

[0014] a hydraulic assembly, the hydraulic assembly comprising:

[0015] a body that extends in a longitudinal direction,

[0016] a plunger pump that includes a pump chamber and a plunger, the plunger reciprocating within the pump chamber, wherein the plunger is coupled to the driving device;

[0017] a hydraulic cylinder that includes a hydraulic chamber and a piston, the piston reciprocating within the hydraulic chamber;

[0018] wherein the pump chamber and the hydraulic chamber are defined within the body and are arranged in series in the longitudinal direction, and the pump chamber is in fluid communication with the hydraulic chamber; and

[0019] a hydraulic fluid storage device for supplying hydraulic fluid to the pump chamber,

[0020] wherein the driving device is arranged in a direction intersecting the longitudinal direction, and the hydraulic fluid storage device is provided on a longitudinal section of the outer surface of the body, and the hydraulic fluid storage device extends in the longitudinal direction to cover the longitudinal range of the longitudinal section and extends in the circumferential direction of the body to cover at least a part of the 360-degree circumferential range of the longitudinal section, such that the hydraulic fluid storage device and the outer surface it covers together define a volume for accommodating the hydraulic fluid.

[0021] In one aspect, the driving device is arranged in a direction perpendicular to the longitudinal direction such that the driving device and the hydraulic assembly form an "L" - shaped arrangement.

[0022] In one aspect, the plunger pump of the hydraulic component is provided with a first check valve that only allows the hydraulic fluid to flow from the hydraulic fluid storage device into the pump chamber and a second check valve that only allows the hydraulic fluid to flow from the pump chamber into the hydraulic chamber. The inlet end of the first check valve is in fluid communication with the hydraulic fluid storage device, the outlet end of the first check valve is in fluid communication with the pump chamber, the inlet end of the second check valve is in fluid communication with the pump chamber, and the outlet end of the second check valve is in fluid communication with the hydraulic chamber.

[0023] In one aspect, corresponding reset devices are respectively provided in the pump chamber and the hydraulic chamber to respectively reset the plunger and the piston.

[0024] In one aspect, the drive device includes a motor and a motion conversion mechanism. The drive device is coupled to the plunger via the motion conversion mechanism, and the motion conversion mechanism converts the rotational motion of the motor into a reciprocating motion along the longitudinal direction.

[0025] In one aspect, the motion conversion mechanism is an eccentric cam, and the rotational axis of the eccentric cam is perpendicular to the longitudinal direction.

[0026] In one aspect, the hydraulic fluid storage device is provided on a longitudinal section of the outer surface of the body corresponding to the pump chamber and is in the form of an annular body that fluid-tightly surrounds the longitudinal section along the circumferential direction.

[0027] In one aspect, the hydraulic component is provided with a pressure relief valve arranged parallel to the longitudinal direction. The pressure relief valve is used to allow the hydraulic fluid to flow back from the hydraulic chamber to the hydraulic fluid storage device to relieve pressure. The inlet end of the pressure relief valve is in fluid communication with the hydraulic chamber, and the outlet end of the pressure relief valve is in fluid communication with the hydraulic fluid storage device.

[0028] In one aspect, the body is formed as a "two-piece", that is, it includes a pump body and a cylinder block. The cylinder block is fluid-tightly connected to one end of the pump body, and the cylinder block and the pump body are made of different materials.

[0029] In one aspect, the hydraulic tool further includes a working head. The working head is coupled to the piston to move under the drive of the piston, and the working head is formed by casting from Al or Mg material.

[0030] In one aspect, the working head is provided with a hole portion, and a reinforcing bushing is inserted into the hole portion. The reinforcing bushing is made of a material with a higher stiffness than the material of the working head.

[0031] Compared with the prior art, which usually arranges the drive device and the hydraulic component in series and / or arranges the main body of the hydraulic component and the hydraulic fluid storage device in series, the present invention arranges the drive device and the hydraulic component to form an "L"-shaped arrangement, and arranges the hydraulic fluid storage device to cover the circumferential range of a longitudinal section of the outer surface of the main body of the hydraulic component in the circumferential direction, so that the longitudinal size of the hydraulic tool is reduced, and it is also more convenient to install and disassemble the hydraulic fluid storage device, thereby facilitating maintenance and replacement. In addition, in the arrangement proposed by the present invention, the hydraulic fluid storage device is arranged away from the drive device, which is advantageously avoided from unnecessary loss of the components of the drive device, thereby significantly saving costs, compared with the prior art, which arranges the hydraulic fluid storage device at the rear end of the drive device and thus immerses the components of the drive device in the hydraulic fluid. At the same time, the arrangement of the hydraulic fluid storage device of the present invention allows it to be made of materials such as rubber, which is further conducive to cost savings.

[0032] Moreover, since the pressure relief valve of the present invention is arranged parallel to the longitudinal direction of the hydraulic assembly, the lateral size of the hydraulic tool is reduced. Furthermore, since the pressure relief valve is arranged parallel to the longitudinal direction, the pressure relief valve can be arranged in the body side by side with the pump chamber or the plunger, which also further reduces the longitudinal size of the hydraulic tool. Therefore, the overall size of the hydraulic tool is more compact.

[0033] In addition, since the present invention can be provided with a "two-piece" body, that is, a separate cylinder body and pump body, the cylinder body and the pump body can be made of different materials. This makes it possible to use only relatively expensive but highly wear-resistant materials to manufacture the cylinder body, thereby avoiding material waste and greatly saving costs. At the same time, forming the cylinder body and the pump body in a "two-piece" manner also makes replacement and maintenance more convenient.

[0034] Finally, since the working head of the present invention can be formed by a casting method using Al or Mg materials, this avoids the large amount of machining required for traditional hydraulic tool working heads using bars or forged steel, thereby reducing processing time, thereby reducing costs, and also reducing weight. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The features and advantages of one or more embodiments of the present invention will become more easily understood through the following detailed description with reference to the accompanying drawings. It should be understood that the drawings are shown in a schematic manner only, and the embodiments of the present invention are not limited to the manner shown in the drawings. For clarity, the same or similar components in the drawings are indicated by the same reference numerals. In the drawings:

[0036] Figure 1 shows a cross-sectional view of a hydraulic tool according to the present invention;

[0037] Figure 2 Shows a partial cross-sectional view of a hydraulic tool according to the present invention;

[0038] Figure 3 Shows a partial exploded perspective view of the cylinder block and the pump body of the hydraulic tool according to the present invention;

[0039] Figure 4 Shows a partial cross-sectional view of the cylinder block and the pump body of the hydraulic tool according to the present invention;

[0040] Figure 5 Shows a perspective view of the working head of the hydraulic tool according to the present invention; and

[0041] Figure 6 Shows a cross-sectional view of the working head of the hydraulic tool according to the present invention. Detailed Description of the Invention

[0042] The present invention will be described in detail below with reference to the accompanying drawings by means of exemplary embodiments. It should be understood that the following detailed description of the present invention is only for the purpose of illustration and is not intended to limit the present invention and its application or use.

[0043] In the specification, orientation terms such as "upper", "lower", "front", "rear", "proximal", "distal", "vertical", "horizontal", etc. are only intended to serve the purpose of clear illustration in combination with the drawings and are not intended to limit the orientation of the relevant components. In actual operation, the positional orientation relationship between the components can be changed according to specific applications.

[0044] Figure 1 Shows a cross-sectional view of a hydraulic tool according to an embodiment of the present invention. Figure 2 Shows Figure 1 A partial cross-sectional view of the hydraulic tool in. The hydraulic tool is generally denoted by reference numeral 1, which has a driving device 10 for providing power to the hydraulic tool and a hydraulic component 12 coupled to the driving device 10. Both the driving device 10 and the hydraulic component 12 are housed in the hydraulic tool housing.

[0045] The hydraulic assembly 12 generally has an axis extending in the longitudinal direction Z, which is shown as horizontal in the drawings of the present application. The hydraulic assembly 12 includes a piston pump 141 and a hydraulic cylinder 142 arranged in series along the longitudinal direction. The piston pump 141 is connected to the driving device 10 at its proximal side (right in the figure) in its longitudinal direction and is connected to the hydraulic cylinder 142 in a fluid communication manner at its distal side (left in the figure) in its longitudinal direction. The piston pump 141 includes a pump body 143 extending in the longitudinal direction, a pump chamber 145 extending in the longitudinal direction defined in the pump body 143, and a piston 147 that can reciprocate in a fluid-tight manner within the pump chamber 145. The hydraulic cylinder 142 includes a cylinder body 144 extending in the longitudinal direction, a hydraulic chamber 146 extending in the longitudinal direction defined in the cylinder body 144, and a piston 148 that can reciprocate in a fluid-tight manner within the hydraulic chamber 146. The pump chamber 145 is in fluid communication with the hydraulic chamber 146, and preferably, the longitudinal axis of the pump chamber 145 is arranged coaxially with the longitudinal axis of the hydraulic chamber 146.

[0046] The driving device 10 is generally arranged in a direction intersecting the longitudinal direction Z. Preferably, as shown in FIG. 1 and Figure 2 as shown, the driving device 10 is generally arranged in a direction perpendicular to the longitudinal direction Z, so that the driving device 10 and the hydraulic assembly 12 form an "L" arrangement. This intersecting arrangement, more specifically, the "L" arrangement reduces the overall longitudinal dimension of the hydraulic tool. The driving device 10 may include a motor (not shown) and a motion conversion mechanism 101, as well as a speed-changing device (not shown in detail) arranged between the motor and the motion conversion mechanism 101, such as a planetary gear, etc. The motor is preferably powered by a battery. The motor can also be replaced by other power sources powered in other ways. The motor is arranged so that it can generate the following rotational motion, that is, the axis T around which the rotational motion rotates is perpendicular to the longitudinal direction Z. In the drawings of the present application, the axis T is shown as extending in the vertical direction.

[0047] The motor inputs its rotational motion to the motion conversion mechanism 101, and the motion conversion mechanism 101 converts this rotational motion into a reciprocating motion along the longitudinal direction Z. The motion conversion mechanism 101 is arranged to be connected to the piston pump 141, more specifically, the piston 147. Therefore, via the motion conversion mechanism 101, the rotational motion of the motor around the vertical axis can be converted into the reciprocating motion of the piston 147 along the longitudinal direction.

[0048] Preferably, the motion conversion mechanism 101 is implemented as an eccentric cam device, which is connected to the motor and installed so that its rotational axis is coaxial or parallel to the axis T of the rotational motion of the motor. The eccentric cam device performs a periodic rotational motion around the vertical rotational axis under the drive of the motor and correspondingly converts this rotational motion into a periodic reciprocating motion along the longitudinal direction Z.

[0049] As Figure 1 and Figure 2 shown, the hydraulic component 12 further includes a hydraulic fluid storage device 16, and the hydraulic fluid storage device 16 is configured to supply hydraulic fluid to the plunger pump 141, and more specifically to the pump chamber 145, so that the plunger pump 141 drives the hydraulic fluid into the hydraulic cylinder 142. More specifically, the proximal section of the pump chamber 145 of the plunger pump 141 near the motion conversion mechanism 101 is configured to accommodate the plunger 147, such that the plunger 147 reciprocates therein in a fluid-tight manner under the drive of the motion conversion mechanism 101, while the distal section of the pump chamber 145 away from the motion conversion mechanism 101 and near the hydraulic cylinder 142 is configured to receive and hold the hydraulic fluid so that the plunger 147 drives the hydraulic cylinder 142 through the hydraulic fluid.

[0050] As Figure 2 shown in detail, the hydraulic fluid storage device 16 is disposed on a longitudinal section of the outer surface of the hydraulic component 12. Preferably, it is disposed on a longitudinal section of the outer surface of the pump body 143. More preferably, it is disposed on a longitudinal section of the outer surface of the pump body 143 corresponding to the distal section of the pump chamber 145 for holding the hydraulic fluid.

[0051] Further as Figure 2 shown, the hydraulic fluid storage device 16 is arranged to extend in the longitudinal direction to cover the longitudinal range of the above-mentioned longitudinal section of the outer surface of the pump body 143, and to extend in the circumferential direction of the pump body 143 to cover the entire circumference of this longitudinal section, that is, the circumferential range of 360 degrees, such that the hydraulic fluid storage device 16 defines a volume for holding the hydraulic fluid together with the outer surface it covers at this longitudinal section.

[0052] In the drawings of the present application, the hydraulic fluid storage device 16 is generally in the form of an annular body that circumferentially surrounds a longitudinal section of the outer surface of the pump body 143.

[0053] Alternatively, the hydraulic fluid storage device 16 may also extend in the circumferential direction to cover only a part of the circumference of this longitudinal section, rather than the entire circumference, that is, a circumferential range less than 360 degrees.

[0054] The hydraulic fluid storage device 16 is fixed to the outer surface of the pump body 143 of the hydraulic component 12 in a fluid-tight manner. For example, it may be fixed by means of a threaded connection, or by riveting, welding, or bonding.

[0055] Preferably, the hydraulic fluid storage device 16 is implemented as an oil bladder made of a rubber material.

[0056] Alternatively, the hydraulic fluid storage device 16 may also be made of any other material suitable for holding the hydraulic fluid and easily fixed to the cylinder block.

[0057] As Figure 2 shown, the overall profile of the cross-section of the hydraulic fluid storage device 16 is approximately trapezoidal. Alternatively, the overall profile of the cross-section of the hydraulic fluid storage device 16 may also be arcuate or other regular or irregular shapes.

[0058] Compared with the prior art where the hydraulic fluid storage device is usually arranged in series with the hydraulic cylinder and the plunger pump, in the present invention, by arranging the hydraulic fluid storage device to circumferentially cover the outer surface of the plunger pump and together define a volume for accommodating the hydraulic fluid, the longitudinal dimension of the hydraulic tool is further reduced, and it is also more conducive to the installation and disassembly of the hydraulic fluid storage device, thus facilitating maintenance and replacement. In addition, in this arrangement proposed by the present invention, the hydraulic fluid storage device is arranged at one end of the plunger pump away from the driving device. Compared with the prior art where the hydraulic fluid storage device is arranged at the rear end of the driving device and thus the components of the driving device are immersed in the hydraulic fluid, this advantageously avoids unnecessary wear of the components of the driving device, thereby significantly saving costs. At the same time, since the hydraulic fluid storage device can be made of a material such as rubber, it is further conducive to cost savings.

[0059] As Figure 2 shown in detail, the hydraulic assembly 12 further includes a first one-way valve 331 and a second one-way valve 332. The first one-way valve 331 is used to enable the hydraulic fluid accommodated in the hydraulic fluid storage device 16 to flow only unidirectionally into the pump chamber 145 of the plunger pump 141, and the second one-way valve 332 is used to enable the hydraulic fluid in the pump chamber 145 to flow only unidirectionally into the hydraulic chamber 146. In the drawings of the present application, the first one-way valve 331 is shown as being arranged in the pump body 143 of the plunger pump 141 and arranged transversely to the longitudinal direction Z. It can be envisaged that the first one-way valve 331 can be arranged at other positions or in other orientations. The inlet end of the first one-way valve 331 is in fluid communication with the hydraulic fluid storage device 16, the outlet end is in fluid communication with the pump chamber 145, and this outlet end does not interfere with the reciprocating movement stroke of the plunger 147, that is, the hydraulic fluid flowing into the pump chamber 145 from this outlet end does not enter the proximal section of the pump chamber 145. The second one-way valve 332 is arranged in the distal section of the pump chamber 145 and is closer to the hydraulic chamber 146 than the first one-way valve 331 in the longitudinal direction Z. The inlet end of the second one-way valve 332 is in fluid communication with the pump chamber 145, and the outlet end is in fluid communication with the hydraulic chamber 146. Therefore, the pump chamber 145 is in fluid communication with the hydraulic chamber 146 via the second one-way valve 332.

[0060] A first reset mechanism 31 may further be provided in the pump chamber 145 of the plunger pump 141 for resetting the plunger 147. Preferably, the first reset mechanism 31 is a spring reset mechanism. Specifically, one end of the spring reset mechanism is fixed or abutted against the end of the pump chamber 145, preferably the end closer to the motion conversion mechanism 101. The other end of the spring reset mechanism is fixedly coupled to the plunger 147 and is arranged such that when the motion conversion mechanism 101 does not apply a driving force to the plunger pump 141 or the driving force is insufficient, the force exerted by the spring reset mechanism on the plunger 147 enables the plunger 147 to remain in its initial position or retracted position or to return to its initial position or retracted position (the rightmost position as shown in the figure), and enables one end of the plunger pump 141 to always remain in abutting contact with the motion conversion mechanism 101.

[0061] Similar to the above-mentioned first reset mechanism 31, a second reset mechanism 32 may also be provided in the hydraulic chamber 146 of the hydraulic cylinder 142 for resetting the piston 148. Preferably, the second reset mechanism is a spring reset mechanism. Specifically, one end of the spring reset mechanism is fixed or abutted against the end of the hydraulic chamber 146, preferably the end closer to the free end. The other end of the spring reset mechanism is fixedly coupled to the piston 148 and is arranged such that when both the plunger pump 141 and the hydraulic cylinder 142 are in an unoperated state, the force exerted by the spring reset mechanism on the piston 148 enables the piston 148 to remain in its initial position or retracted position or to return to its initial position or retracted position (the rightmost position as shown in the figure).

[0062] The hydraulic assembly 12 further includes a pressure relief valve 34 located between the hydraulic cylinder 142 and the fluid storage device 16. The pressure relief valve 34 is arranged to automatically open when the instantaneous hydraulic pressure in the hydraulic cylinder 142 reaches a preset threshold, for example, 700 bar, so that the hydraulic fluid in the hydraulic cylinder 142 can flow back into the hydraulic fluid storage device 16 to relieve the pressure. Additionally, the pressure relief valve 34 can be arranged to also be opened manually, for example, to manually trigger pressure relief when the hydraulic tool operation is completed, not powered on, or there is no power input. The inlet end of the pressure relief valve 34 is in fluid communication with the hydraulic chamber 146 of the hydraulic cylinder 142, and the outlet end is in fluid communication with the hydraulic fluid storage device 16.

[0063] In an embodiment of the present invention, as Figure 2 shown, the pressure relief valve 34 is arranged in the pump body 143 of the plunger pump 141 and is arranged parallel to the longitudinal direction of the hydraulic assembly 12, and thus also parallel to the pump chamber 145 or the plunger 147, that is, the pressure relief valve 34 is arranged side by side with the pump chamber 145 or the plunger 147.

[0064] Compared with the prior art where it is arranged transversely to the longitudinal axis of the hydraulic component, the pressure relief valve being arranged parallel to the longitudinal direction reduces the lateral dimension of the hydraulic tool. At the same time, the pressure relief valve being arranged side by side with the pump chamber or the plunger in the pump body also further reduces the longitudinal dimension of the hydraulic tool. Therefore, the overall dimension of the hydraulic tool is more compact.

[0065] The operation process of the hydraulic tool according to the present invention is described below. In the initial state, the plunger 147 of the plunger pump 141 and the piston 148 of the hydraulic cylinder 142 are both in their initial positions (i.e., the rightmost end in the figure). During operation, driven by the motor of the driving device 12, the rotation of the motion conversion mechanism 101 pushes the plunger 147 to move forward from its initial position to its extended position. And when the plunger 147 returns from its extended position to its initial position or retracted position, the first one-way valve 331 opens due to the lower pressure in the pump chamber 145 or through the control system, allowing the hydraulic fluid in the hydraulic fluid storage device 16 to flow into the pump chamber 145. When the plunger 147 moves forward from the retracted position to the extended position again due to the rotation of the motion conversion mechanism 101, it pushes the hydraulic fluid forward and thus forces the second one-way valve 332 to open, enabling the hydraulic fluid in the pump chamber 145 to flow into the hydraulic chamber 146. When the plunger 147 returns to the retracted position again under the action of the first reset mechanism 31, due to the decrease in pressure in the pump chamber 145, more fluid flows from the hydraulic fluid storage device 16 into the pump chamber 145, and the above process is repeated. The plunger 147 makes repeated reciprocating motions to push more and more hydraulic fluid from the pump chamber 145 into the hydraulic chamber 146, so that when a certain hydraulic pressure is reached, the piston 148 of the hydraulic cylinder 142 is displaced, pushing the piston 148 in the direction away from the plunger 147, i.e., moving distally. The piston 148 further drives the working head 18 to move distally to manipulate the tool head. When the hydraulic tool is completed, the pressure relief valve 34 is manually opened to discharge the fluid in the hydraulic chamber 146 into the hydraulic fluid storage device 16, and at the same time, the piston 148 returns to the initial position under the action of the second reset mechanism 32.

[0066] As described above, in the embodiment of the present invention, the plunger 147 of the plunger pump 141 is received in the pump body 143 to reciprocate in a fluid-tight manner in the pump body 143, and the piston 148 of the hydraulic cylinder 142 is received in the cylinder block 144 to reciprocate in a fluid-tight manner within the cylinder block 144. As Figure 1 shown, the pump body 143 and the cylinder block 144 together form the body of the hydraulic component 12, that is to say, the body of the hydraulic component 12 of the hydraulic tool according to the present invention is formed in a "two-piece" manner, where the cylinder block 144 is at least partially received in the pump body 143 at one end of the pump body 143. Figure 3 and Figure 4Further shown is a partial exploded perspective view and a partial sectional view of the pump body 143 and the cylinder block 144 of the hydraulic tool according to the present invention. As shown, the cylinder block 144 is at least partially received within the pump body 143, preferably in a fluid-tight manner. The cylinder block 144 may be mechanically connected to the pump body 143, preferably in a threaded connection. Further, a sealing device, such as an O-ring 201, may be provided between the pump body 143 and the cylinder block 144.

[0067] Forming the body of the hydraulic assembly in a "two-piece" manner allows the pump body of the plunger pump and the cylinder block of the hydraulic cylinder to be made of different materials. For example, a more expensive but more wear-resistant material can be used to manufacture the cylinder block, while a less wear-resistant but cheaper material can be used to manufacture the pump body. Only the more worn parts of the hydraulic assembly are made of the more expensive material, without having to use such an expensive material to manufacture the entire body of the hydraulic assembly, which avoids waste of materials and greatly saves costs. At the same time, setting the cylinder block separately also makes replacement and maintenance more convenient.

[0068] However, as can be understood by those skilled in the art, the body of the hydraulic assembly 12 of the hydraulic tool according to the present invention may also be formed in a "one-piece" manner, i.e., the pump body 143 and the cylinder block 144 are formed integrally.

[0069] As Figure 1 and Figure 5 shown, the hydraulic tool according to the present invention may further include a working head 18. One end of the working head 18 is coupled to the end of the hydraulic cylinder 142 opposite to the plunger pump 141, more specifically, the free end of the piston 148, and thus reciprocates with the reciprocating motion of the piston 148. The other end of the working head 18 may be detachably connected with a corresponding tool head (not shown), which is used for performing required industrial operations, such as crimping, curling, shearing, punching operations, etc.

[0070] Figure 5 and Figure 6 Shown are a perspective view and a sectional view of the working head 18 according to the present invention. The working head according to the present invention may be made of Al or Mg material. Due to the characteristics of the Al or Mg material, the main structure of the working head 18 can be formed by a casting method, such as die casting, permanent mold casting, sand mold casting, etc., and then a small amount of machining is used as needed to form other structures such as holes. The working head according to the present invention only requires very little machining to form the final structure, which can avoid the large amount of machining required for the working head of a traditional hydraulic tool made of bar stock or forged steel, thus reducing the machining time, further reducing the cost, and at the same time reducing the weight.

[0071] To avoid the problem of insufficient strength caused by the relatively low hardness or stiffness of the Al or Mg material, an enhanced bushing 182, such as a steel bushing, can be provided in the area of the working head 18 that is subject to relatively high stress or pressure, such as the hole portion 181 for connecting to the tool head, e.g., for inserting a pin of the tool head, to meet the strength requirements.

[0072] As described above, the present application discloses some embodiments and mentions some possible alternatives, and all the mentioned technical solutions are within the scope of protection of the present application. In addition, certain obvious modifications recognized by those of ordinary skill in the art will also fall within the scope of protection of the present application.

[0073] Although the present invention has been described with reference to exemplary embodiments, it should be understood that the present invention is not limited to the specific embodiments / examples detailed and illustrated herein, and those skilled in the art can make various changes to the exemplary embodiments without departing from the scope defined by the appended claims.

[0074] Reference numerals:

[0075] Drive device 10

[0076] Motion conversion mechanism 101

[0077] Hydraulic component 12

[0078] Plunger pump 141

[0079] Hydraulic cylinder 142

[0080] Pump body 143

[0081] Cylinder block 144

[0082] Pump chamber 145

[0083] Hydraulic chamber 146

[0084] Plunger 147

[0085] Piston 148

[0086] Hydraulic fluid storage device 16

[0087] First reset mechanism 31

[0088] Second reset mechanism 32

[0089] First check valve 331

[0090] Second check valve 332

[0091] Pressure relief valve 34

[0092] O-ring seal 201

[0093] Working head 18

[0094] Hole part 181

[0095] Reinforcing bushing 182.

Claims

1. A hydraulic tool, the hydraulic tool comprises: a driving device; and a hydraulic assembly, the hydraulic assembly comprising: a body that extends in a longitudinal direction, a piston pump including a pump chamber and a piston that reciprocates within the pump chamber, wherein the piston is coupled to the driving device; a hydraulic cylinder including a hydraulic chamber and a piston that reciprocates within the hydraulic chamber; wherein the pump chamber and the hydraulic chamber are defined within the body and arranged in series along the longitudinal direction, and the pump chamber is in fluid communication with the hydraulic chamber; and a hydraulic fluid storage device for supplying hydraulic fluid to the pump chamber, characterized in that the driving device is arranged in a direction intersecting the longitudinal direction, the hydraulic fluid storage device is provided on a longitudinal section of the outer surface of the body, and the hydraulic fluid storage device extends along the longitudinal direction to cover the longitudinal range of the longitudinal section and extends along the circumferential direction of the body to cover at least a part of the 360-degree circumferential range of the longitudinal section, such that the hydraulic fluid storage device and the outer surface it covers together define a volume for accommodating the hydraulic fluid, and the driving device is arranged in a direction perpendicular to the longitudinal direction such that the driving device and the hydraulic assembly form an "L" arrangement. The driving device includes a motor and a motion conversion mechanism. The driving device is coupled to the piston via the motion conversion mechanism. The motion conversion mechanism converts the rotational motion of the motor into a reciprocating motion along the longitudinal direction, and the motion conversion mechanism is an eccentric cam, and the axis of rotation of the eccentric cam is perpendicular to the longitudinal direction.

2. The hydraulic tool according to claim 1, characterized in that the piston pump of the hydraulic assembly is provided with a first one-way valve that only allows the hydraulic fluid to flow from the hydraulic fluid storage device into the pump chamber and a second one-way valve that only allows the hydraulic fluid to flow from the pump chamber into the hydraulic chamber. The inlet end of the first one-way valve is in fluid communication with the hydraulic fluid storage device, the outlet end of the first one-way valve is in fluid communication with the pump chamber, the inlet end of the second one-way valve is in fluid communication with the pump chamber, and the outlet end of the second one-way valve is in fluid communication with the hydraulic chamber.

3. The hydraulic tool according to claim 1, characterized in that corresponding reset devices are respectively provided in the pump chamber and the hydraulic chamber for respectively resetting the piston and the piston.

4. The hydraulic tool according to claim 1, characterized in that the hydraulic fluid storage device is provided on a longitudinal section of the outer surface of the body corresponding to the pump chamber and is in the form of an annular body that surrounds the longitudinal section in a fluid-tight manner along the circumferential direction.

5. The hydraulic tool according to any one of claims 1 to 4, characterized in that The hydraulic component is provided with a pressure relief valve arranged parallel to the longitudinal direction, and the pressure relief valve is configured to allow the hydraulic fluid to flow back from the hydraulic chamber to the hydraulic fluid storage device to relieve pressure. The inlet end of the pressure relief valve is in fluid communication with the hydraulic chamber, and the outlet end of the pressure relief valve is in fluid communication with the hydraulic fluid storage device.

6. The hydraulic tool according to any one of claims 1 to 4, wherein, the body is formed as a "two-piece", that is, it includes a pump body and a cylinder block. The cylinder block is connected to one end of the pump body in a fluid-tight manner, and the cylinder block and the pump body are made of different materials.

7. The hydraulic tool according to any one of claims 1 to 4, wherein, the hydraulic tool further includes a working head, the working head is coupled to the piston to move under the drive of the piston, and the working head is formed by a casting method from Al or Mg material.

8. The hydraulic tool according to claim 7, wherein, the working head is provided with a hole portion, and a reinforcing bushing is inserted into the hole portion. The reinforcing bushing is made of a material having a greater stiffness than the material of the working head.

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