Rolling type grooving tool

Abstract

An apparatus (1) for rolling a circumferential outer slot (994) in a pipe (99). The apparatus (1) comprises a clamp (50) and a grooving tool (10). In a fixed position, the clamp (50) is configured to engage an inner wall (996) of the pipe (99) and fix the device (1) to a pipe end portion (990) such that the pipe central axis (X99) is coaxial with the device central axis (X1), and the grooving tool (10) is rotatable about the central axis (X1), the grooving tool (10) comprising a hydraulic piston (12) and at least one wheeled holder (110), the hydraulic piston (12) is displaceable along the central axis (X1), the hydraulic piston (12) is configured to displace the wheeled holder (110) in a radial direction relative to the central axis (X1) between an idle position (1102) and a slotted position (1104), and the wheeled holder (110) comprises a slotted wheel (111).

Description

[0001] This invention relates to a tool for grooving pipes. More specifically, the invention relates to a grooving apparatus arranged for rolling circumferentially outward grooving at an end portion of a pipe. The grooving apparatus forms a central axis. The grooving apparatus includes a clamp and a grooving tool. The clamp can be configured between a released position and a fixed position. In the fixed position, the clamp is configured to engage the inner wall of the pipe and secure the grooving apparatus to the end portion of the pipe such that the pipe's central axis is coaxial with the central axis. The grooving tool is rotatable about the central axis. Background Technology

[0002] To join pipes together axially and form a waterproof joint, it is known to create a slot at each end of the pipe and connect the pipes using a metal fitting that interferes with the slot. A gasket is typically placed between the pipe and the fitting.

[0003] Grooving is performed by rotating the pipe inside or around the grooving tool, while one or more rollers apply radial force to the outside of the pipe. The rollers cause radial deformation of the pipe, creating a groove around the pipe's perimeter and a corresponding protrusion inside.

[0004] Patent document GB2014072 discloses a fixed roller grooving tool comprising a pair of rollers rotatable about substantially parallel axes, one roller being driven by a motor and the other freely rotatable. The driven roller is located inside the pipe, while the freely rotatable roller is located outside. During grooving, the pipe rotates around the driven roller, while the freely rotatable roller applies a deformation force to the outside of the pipe.

[0005] Patent document JP2000210723 discloses a grooving tool that includes multiple rollers that apply radial force to a pipe. The tool does not have internal supports.

[0006] Patent document EP1275447 discloses a portable roller grooving tool in which grooving is performed manually by rotating a crank. In one embodiment, the pipe is rigidly supported, so the portable roller grooving tool rotates about the pipe. In another embodiment, the portable roller grooving tool is rigidly fixed, and the pipe to be grooved rotates relative to it during the grooving operation.

[0007] Patent document WO03089159 discloses a track-mounted roller grooving tool for pipes. The track-mounted roller grooving tool is mounted on a workbench and includes an adjustment device for aligning the track-mounted roller grooving tool with the pipe.

[0008] Existing driven roller grooving tools have several drawbacks. Stationary tools require the pipe to be brought to the tool. This is time-consuming and often causes problems when working on construction sites, where long pipes must pass through door openings and even from one floor to another. Pipe rotation is also a disadvantage. Rotating the pipe requires additional support and must be secured to prevent warping if the pipe's central axis is not aligned with its axis of rotation.

[0009] The disadvantages of portable rolling slotting tools are: they are heavy for extended periods of use, and the crank's center is not aligned with the pipe's center, meaning the crank will rotate in a spiral motion. They also require, for example, the use of vises to securely fasten the pipe.

[0010] The purpose of this invention is to remedy or reduce at least one of the disadvantages of the prior art, or at least to provide a useful alternative to the prior art.

[0011] This objective is achieved by the features specified in the following description and the attached scheme. Summary of the Invention

[0012] This invention is defined by the independent patent scheme. Dependent schemes define advantageous embodiments of the invention.

[0013] In a first aspect, the invention relates more specifically to a grooving apparatus arranged for rolling a circumferentially outward grooving at an end portion of a pipe. The grooving apparatus forms a central axis. The grooving apparatus includes a clamp and a grooving tool. The clamp is configured between a released position and a fixed position. In the fixed position, the clamp is configured to engage the inner wall of the pipe and secure the grooving apparatus to the end portion of the pipe such that the pipe's central axis is coaxial with the central axis. The grooving tool is rotatable about the central axis, and - The grooving tool includes a hydraulic piston and at least one wheel retainer; - The hydraulic piston can be displaced in a direction along the central axis; - The hydraulic piston is configured to shift the wheel retainer radially relative to the central axis between a free-spinning position and a slotted position; and - The wheel retainer includes a slotted wheel.

[0014] The hydraulic piston can be displaced parallel to the central axis.

[0015] The pipe can be a spray pipe made of metal. The grooving depth can be set by the stroke length of the hydraulic piston. The pipe wall thickness is typically 3-5mm. The effect of the grooving tool rotating relative to the housing and pipe is that both the equipment and the pipe remain stationary, i.e., they do not rotate. Because the pipe does not rotate, there is no risk of warping, and grooving can be performed on curved pipes. This makes the equipment more flexible than stationary grooving tools and improves operator health and safety.

[0016] The grooving device can be handheld and not fixed to a stationary setting. Therefore, it is advantageous for the grooving device to have a small external size. A hydraulic piston that can be displaced along a central axis can achieve a piston area without substantially increasing the external size of the grooving device. Therefore, a hydraulic piston that can be displaced along a central axis can be made compact and have a small external size. A large piston area of ​​the hydraulic piston produces several other effects, which will be described below. The hydraulic piston can be positioned within a cylinder. The cylinder may need to be filled with hydraulic fluid to displace the hydraulic piston. Compared to a small piston area, a large piston area requires more hydraulic fluid to displace the hydraulic piston a given distance. The larger fluid volume makes it easier to displace the piston at a uniform and consistent rate, because for a given displacement rate, the fluid flow rate can be maintained at a higher level. Therefore, the wheel retainer can be displaced at a controlled rate. Another effect is that the hydraulic pressure required to generate a given piston force is reduced with a large piston area compared to a smaller piston area. This reduces wear on the hydraulic pump supplying the hydraulic fluid and can reduce strain on internal components such as the cylinder.

[0017] Wheel retainers may include slotted wheels. A slotted wheel may include a ridge and a smaller diameter on each side of the ridge. The effect of the smaller diameter on each side of the ridge is that the slotting depth can be set and limited by the smaller diameter that engages with the outer wall of the pipe. The slotting depth can be set by a combination of the stroke length of the hydraulic piston and the smaller diameter on each side of the ridge.

[0018] A large-diameter grooving wheel will roll circumferentially outwards in the pipe end portion with a smaller force compared to a small-diameter grooving wheel. This is known to those skilled in the art. The large piston area of ​​the hydraulic piston, which can be displaced along the central axis, allows for a larger grooving wheel within the wheel retainer without increasing the external dimensions of the grooving device. The grooving device may include a single hydraulic piston that can be displaced parallel to the central axis or multiple hydraulic pistons that can be displaced along or parallel to the central axis.

[0019] The hydraulic piston can be biased toward the starting position. The biasing device can be a single spring or multiple springs. A larger piston area allows for the use of a larger spring compared to a spring achievable with a smaller piston area. A larger and therefore more powerful spring can return the hydraulic piston to the starting position at a higher rate than a weaker, smaller spring. Therefore, because the grooving wheels return to their starting positions simultaneously, the grooving equipment is used more efficiently, and the pipe is released from the grooving equipment.

[0020] The hydraulic piston is configured to displace the wheel retainer radially relative to a central axis between an idle position and a slotted position. In the idle position, the hydraulic piston may be in the initial position, and the slotted wheel may be positioned at a distance from the pipe, i.e., there is a gap between the slotted wheel and the pipe. The wheel retainer may include a protrusion, and the hydraulic piston may include a recess. The protrusion may be formed to be positioned within the recess such that axial displacement of the hydraulic piston produces radial displacement of the wheel retainer. The protrusion and the recess may form an angle with the central axis such that the wheel retainer is radially displaced when the hydraulic piston is displaced parallel to the central axis. It will be apparent to those skilled in the art that various alternative embodiments can be formed to displace the wheel retainer radially when the hydraulic piston moves along or parallel to the central axis. One example could be having a protrusion in the hydraulic piston and a recess in the wheel retainer, etc.

[0021] At the grooving position, the hydraulic piston has shifted, causing the grooving wheel to abut against the pipe and begin forming a groove in the pipe. The grooving position can be dynamic, with the wheel retainer shifting as the grooving deepens.

[0022] In a preferred embodiment, the grooving tool may include at least three wheel retainers. If two grooving wheels are not precisely aligned with the center axis of the pipe, the two grooving wheels may attempt to push the pipe out of the center. The advantage of three or more grooving wheels is that they are self-aligning. Therefore, the wheel retainers can shift at a uniform rate, so that radial forces are held within the pipe and not absorbed by the clamps.

[0023] The grooving tool may include a base element, and a wheel retainer may be radially displaceable to the base element. The base element may include a groove within which a protrusion in the wheel retainer may be displaced radially. The base element may receive rotational force and thus transmit that force to the wheel retainer connected to it. The hydraulic piston may be displaced relative to the base element along or parallel to a central axis. Therefore, the base element may be used to limit the stroke length of the hydraulic piston. The base element may serve as a relative component for biasing the hydraulic piston back to its starting position. The effect of the aforementioned technical features regarding the base element can be a compact design that reduces the number of components rotating relative to each other.

[0024] The base element can be used to guide hydraulic fluid from the hydraulic pump to the cylinder.

[0025] The grooving device can be configured to receive rotational force from a drive shaft. The drive shaft can be offset from the central axis, and the grooving device can be configured to receive hydraulic fluid from a pressure line. Offsetting the drive shaft reduces the complexity of the fixture because the center of the device does not include rotating components. Using hydraulic fluid from a pressure line reduces the burden on the operator to move the hydraulic piston.

[0026] Off-center drive shafts can transmit rotational force to the grooving device. The grooving tool may include an internal spur gear. Base elements are rotatably and rigidly connected to the internal spur gear. Therefore, this drive shaft can rotate the grooving tool and has lower clamping complexity compared to a drive shaft coaxial with the central axis.

[0027] The fixture can be configured by shifting the shaft parallel to the central axis. This allows the use of fixtures similar to those known in the art. By shifting the shaft, the fixture can be activated at a position far removed from where the grooving tool can rotate.

[0028] The rotational force and hydraulic fluid flow can be provided by a battery-powered power unit. Both the grooving device and the power unit can be handheld. Because the grooving device can be manufactured compactly, both the device and power unit can be handheld. The advantage of a handheld grooving device is that it is easier to align the device correctly with the pipe, especially when the pipe is long. A handheld grooving device also allows the user to move freely between locations where the grooving is needed. Using battery power to power the grooving device allows the user to move freely between locations without needing a power source at each location.

[0029] The grooving tool may include a visual indicator that indicates the position of the hydraulic piston within the cylinder, thereby indicating the depth of the grooving or when the grooving is complete.

[0030] A hydraulic pump and drive mechanism are also described, which can be connected to a power unit. The hydraulic pump and drive mechanism may include a hydraulic pump, a fluid reservoir, and pressure lines. The hydraulic pump can be connected to the fluid reservoir and pressure lines. The hydraulic pump and drive mechanism may include a rotatable input shaft that can be connected to the power unit and configured to rotate the hydraulic pump. The hydraulic pump and drive mechanism may include a drive shaft configured to rotate via the input shaft. The drive shaft may be offset from the input shaft.

[0031] The aforementioned hydraulic pump and drive mechanism may be a first embodiment of a hydraulic pump and drive mechanism. The hydraulic pump and drive mechanism can be connected to a device. This device may have different technical parameters that need to be considered. Some devices may require the power unit to be aligned linearly with the device. Other devices may require the power unit to be angled, resulting in a shorter length for the hydraulic pump and drive mechanism assembled with the power unit.

[0032] In a second embodiment of the hydraulic pump and drive mechanism, the position of the input shaft relative to the drive shaft may be less important. The hydraulic pump and drive mechanism may be driven by a power unit and may include a hydraulic pump, a fluid reservoir, and a pressure line. The hydraulic pump may be connected to the fluid reservoir and the pressure line, wherein: - A rotatable input shaft can be connected to the power unit. - The input shaft can be configured to rotate the hydraulic pump. - The input shaft may be configured to rotate the drive shaft; and - The hydraulic pump and drive mechanism may include an attachment portion at a distal end opposite to the input shaft, the attachment portion may form a central axis and may include the drive shaft and the pressure line, the drive line being offset from the central axis.

[0033] In the second embodiment, the input axis may be offset from the drive axis.

[0034] The following instructions also apply to the first and second embodiments of the hydraulic pump and drive mechanism described above.

[0035] The hydraulic pump and drive mechanism can be part of a handheld device. A rotatable input shaft can be connected to the power unit, allowing the power unit to be detached from the hydraulic pump and drive mechanism. The rotatable input shaft can be connected to the power unit via a quick-connect fitting, allowing the power unit to be used for other applications when the hydraulic pump and drive mechanism are not in use. The power unit can be battery-powered. The power unit can be a handheld drilling rig known in the art. The advantage is that the hydraulic pump and drive can be configured across multiple devices and can be easily carried and used by the user.

[0036] Hydraulic pumps and drive mechanisms can be used in various devices that utilize hydraulic fluid flow and rotational force. These devices can have different operating parameters. The operating parameters of a drive shaft can be its rotational speed and / or torque. The operating parameters of a hydraulic pump can be its hydraulic flow rate and / or hydraulic pressure, depending on the pump's specifications. Therefore, the hydraulic pump and drive mechanism may need to be configured such that an input shaft can satisfy both the drive shaft's operating parameters and the hydraulic pump's specifications. Depending on the operating parameters, different embodiments may be required. Several embodiments are described below.

[0037] One embodiment may involve the input shaft being connected to a through shaft in a hydraulic pump, or it may be a through shaft in a hydraulic pump. The through shaft is rotatably rigidly connected to a spur gear, which rotates a spur gear rotatably rigidly connected to a drive shaft. The spur gear can be used to adjust the speed and torque of the drive shaft, such that the hydraulic pump can rotate at a first speed and a first torque, while the drive shaft rotates at a second speed and a second torque.

[0038] The drive shaft can be parallel to the input shaft. This allows the use of spur gears to adapt the speed and torque between the input and drive shafts when the drive shaft is offset from the input shaft. Alternatively, the spur gears can simply offset the drive shaft from the input shaft without adapting to speed and torque. Spur gears can be used to transmit rotational force from the input shaft to multiple drive shafts. Hydraulic pumps and drive mechanisms can include two drive shafts, also known as a dual-power drive system. The advantage of a dual-power drive system is that power can be distributed to two drive shafts with associated gears.

[0039] A hydraulic pump can be configured to rotate a drive shaft via a rotationally rigid connection between the hydraulic pump and the drive shaft. The effect is that, in this embodiment, the drive shaft can rotate at the same speed as the hydraulic pump. The hydraulic pump and drive mechanism may include a reduction gear and an intermediate shaft. The input shaft may include a first spur gear that rotates a second spur gear. The second spur gear can be rotationally rigidly connected to the intermediate shaft. The first and second spur gears can reduce the rotational speed of the intermediate shaft relative to the input shaft. The intermediate shaft can be rotationally rigidly connected to the hydraulic pump and rotate the hydraulic pump. The effect is that the hydraulic pump can have a lower rotational speed relative to the input shaft. The term "rotationally rigidly connected" is used herein to describe two parts that can be disconnected at some point in time, such as a threaded or keyed connection, or two parts that can be permanently connected, such as a welded connection, or one part that can be machined into part of another part. The intermediate shaft can be, for example, a shaft machined into part of the second spur gear or the hydraulic pump.

[0040] In an alternative embodiment, the hydraulic pump can be an external gear pump. External gear pumps are well known in the art. An intermediate shaft is rotatably and rigidly secured between a first pump gear and a reduction gear in the external gear pump, and a drive shaft is rotatably and rigidly connected to a second pump gear in the external gear pump. The effect is that the external gear pump can be used to offset the drive shaft from the input shaft without using an additional spur gear or having an unnecessarily large spur gear. Therefore, the construction between the input shaft and the drive shaft is compact, making the hydraulic pump and drive mechanism lighter and easier to operate.

[0041] The hydraulic pump and drive mechanism may include two external gear pumps. Having two external gear pumps can double the hydraulic output, increase redundancy in the hydraulic system, or allow for the formation of two separate hydraulic circuits. Each of the two external gear pumps can be connected to a drive shaft, allowing for two drive shafts in the drive mechanism. The two external gear pumps can be configured in at least one of parallel or series configurations. A parallel configuration can increase the hydraulic fluid flow compared to a single external gear pump. A series configuration can increase the hydraulic pressure compared to a single external gear pump.

[0042] The hydraulic pump and drive mechanism may include a control lever. The control lever can be configured between an active position and a passive position. When using the hydraulic pump and drive mechanism, the control lever can be used to enhance safety. This can be accomplished by using the control lever to start or stop components of the hydraulic pump and drive mechanism and / or components of the connected equipment. The connected equipment is the equipment attached to the hydraulic pump and drive mechanism. In the passive position, the pressure line can be connected to a fluid reservoir, and in the active position, the pressure line can be disconnected from the fluid reservoir. The effect is that in the passive position, the hydraulic pump cannot generate hydraulic pressure when hydraulic fluid is directed to the fluid reservoir. In the active position, the hydraulic pump can generate a flow of hydraulic fluid and hydraulic pressure within the pressure line. The control lever can be configured to displace the shaft between a first position and a second position in a direction parallel to the drive shaft. The control lever positioned in the passive position configures the shaft to the first position. The control lever positioned in the active position configures the shaft to the second position. The shaft can form a shaft axis. The shaft axis can be coaxial with the central axis of the attachment portion. The drive shaft can be offset from this shaft. The shaft can be connected to the connected equipment. An axis in the second position can activate a feature of the connected device. An axis in the first position can deactivate a feature of the connected device.

[0043] The control lever can be a handle that can rotate around a pivot point, a sliding switch, or a pressable button.

[0044] The hydraulic pump and drive mechanism can be small and handheld. This may mean that the hydraulic pump and drive mechanism can be oriented in all possible directions. Therefore, it is advantageous to seal the fluid reservoir from the surrounding environment so that fluid does not drip from vents. The fluid volume within the reservoir may change as fluid is discharged from the hydraulic pump and enters the connected equipment. This may need to be compensated for so that the hydraulic pump operates according to its specifications. The fluid reservoir can be connected to a volume compensation device. Fluid reservoirs and volume compensation devices can appear in many embodiments and will be described in more detail later.

[0045] The pressure line can be connected to at least one of a pressure reducing valve and a flow restrictor. The pressure line can be part of a hydraulic circuit. A hydraulic pump supplies hydraulic fluid to the pressure line, thus generating hydraulic pressure. The pressure reducing valve connected to the pressure line ensures that the hydraulic pressure does not exceed a predetermined pressure. This is a safety feature. Connecting the pressure line to the flow restrictor allows the flow of hydraulic fluid from the hydraulic pump to be set to a predetermined rate. This can improve the operation of the connected equipment.

[0046] A hydraulic pump and drive mechanism can be configured to connect to a rotatable device. The hydraulic pump can be connected to the rotatable device via one or more hydraulic lines. A shaft can be connected to the rotatable device. A drive shaft can be connected to the rotatable device and transmit rotational force to it. The rotatable device can be a grooving device.

[0047] A rigid fluid reservoir for hydraulic fluid is also described, the rigid fluid reservoir comprising a rigid housing and an outlet, wherein: - The rigid fluid reservoir can be sealed from the surrounding environment. - The rigid fluid reservoir may include an inflatable device, which may be positioned within the rigid housing; and - Inflatable devices can communicate with the surrounding environment through holes in a rigid shell.

[0048] A through hole can be a hole that passes through the wall that forms a rigid shell.

[0049] The fluid can be oil used in hydraulic applications.

[0050] The sealing effect of a rigid fluid reservoir against its surroundings allows it to be placed in any orientation without leakage from vents. This can be highly advantageous if the rigid fluid reservoir is to be connected to or part of a handheld device. The inflatable device can inflate or deflate depending on whether fluid is being drawn from or supplied to the rigid fluid reservoir. Therefore, the inflatable device provides volume compensation.

[0051] The inflatable device inflates or deflates as fluid is drawn from or returned to the rigid fluid reservoir. To inflate the inflatable device, air from the surrounding environment is drawn into it. To deflate the inflatable device, air is vented from the inflatable device to the air surrounding the rigid fluid reservoir. Inflating and deflation occur due to the pressure difference created by the fluid being drawn from or returned to the rigid housing. Using ambient air to inflate or deflate the inflatable device reduces complexity by preventing it from being inflated to a predetermined pressure.

[0052] Air drawn into the inflatable device from the surrounding environment may be contaminated, causing debris to accumulate inside the device over time. A through-hole can be positioned inside the outer cover. Its effect is to create a barrier between the inflatable device and debris in the air from the surrounding environment. The outer cover can be a filter or a mesh. The outer cover can be part of the device.

[0053] Inflatable devices may include flexible materials. Inflatable devices may be airbags or balloons. Inflatable devices may include corrugated metal tubing.

[0054] If the rigid fluid reservoir is used with a handheld device, it is advantageous to make the rigid fluid reservoir as compact as possible. The inflatable device may include a longitudinal axis. The longitudinal axis can extend from the through-hole to the distal opposite end of the inflatable device. The inflatable device can expand along the longitudinal axis. The longitudinal axis can be parallel to a shaft. The shaft can be positioned to extend from inside the rigid fluid reservoir to the outside of the rigid fluid reservoir. The shaft can extend through the rigid fluid reservoir.

[0055] Rigid fluid reservoirs can be part of hydraulic pumps and drive mechanisms.

[0056] In a second aspect, the invention relates more specifically to a grooving system arranged for rolling circumferentially outward grooving at the end portion of a pipe, wherein: - The grooving system includes grooving equipment according to the first aspect of the invention; - The grooving system includes a hydraulic pump and drive mechanism, a fluid reservoir, and fixtures; - The hydraulic pump and drive mechanism are configured to be connected to the power unit and receive rotational force from the power unit via the input shaft; - The hydraulic pump and drive mechanism are configured to generate an output, which includes a flow of hydraulic fluid and a rotational force, and the output is transmitted to the grooving device; - The fixture forms a central axis, which is coaxial with the central axis of the grooving tool; - The clamp is configured to engage the inner wall of the pipe and secure the end portion of the pipe to the slotting equipment.

[0057] The hydraulic pump and drive mechanism can be connected to the grooving equipment, allowing the drive shaft and hydraulic circuit to transmit force to the grooving tool within the grooving equipment. The fixture can be configured via a control lever in the hydraulic pump and drive mechanism.

[0058] The hydraulic pump and drive mechanism may include devices for increasing torque and reducing the rotational speed from the power unit to the grooving tool. This effectively regulates the rotational speed (revolutions per minute - rpm) and torque from the power unit to provide the correct rpm and torque to the grooving tool. The power unit connected to the equipment (such as a handheld drill) typically rotates at 600-700 rpm. The grooving tool typically rotates at 60 rpm. Therefore, the hydraulic pump and drive mechanism can be arranged to reduce the rpm by approximately 85-90%. Gear ratio adjustment can be accomplished using gears. Gear ratio adjustment can also be accomplished using belts or chains. Gear ratio adjustment can be performed in one or more stages.

[0059] The hydraulic pump and drive mechanism may include at least one drive shaft positioned offset from the center axis of the grooving tool. The effect is that the fixture can be less complex because the drive shaft is offset from the fixture's center axis. The hydraulic pump and drive mechanism may also include two drive shafts offset from the fixture's center axis. This is referred to as a dual-power drive system. The advantage of a dual-power drive system is that power can be distributed to two drive shafts with associated gears.

[0060] The drive shaft can be connected at a first end to a set of gears arranged to transmit power from the input drive shaft to a drive shaft offset from the center axis of the grooving tool. The drive shaft can be connected at a second end to an internal gear ring with internal teeth. Compared to an embodiment with external teeth, the effect of internal teeth is that the drive shaft can be positioned closer to the center axis of the grooving tool. This makes the grooving system more compact.

[0061] The hydraulic pump and drive mechanism may include a set of gears arranged to transmit power from the input shaft to one or more drive shafts offset from the center axis of the slotting tool.

[0062] The clamp may include multiple jaws that are radially displaceable by means of an eccentric connector attached to a shaft. The shaft may be displaced along the central axis of the clamp. The clamp may also include multiple jaws connected to a corresponding number of cones connected to the shaft. As the shaft is displaced along the central axis of the clamp, the cones guide the jaws radially outward or inward. In a preferred embodiment, the clamp may include three or more jaws, as these three or more jaws are automatically aligned relative to the pipe.

[0063] The eccentric connector can be operated by a control lever. The control lever is accessible from the outside. Its effect is that, compared to, for example, a small screw or button, the control lever can achieve a greater torque for displacing the eccentric connector. For a screw to achieve the same torque, the screw must have a radius equal to the length of the control lever. The control lever also provides excellent visualization of the eccentric connector's position. If the axial displacement of the eccentric connector is equal to a 180-degree rotation of the shaft used for the eccentric connector, the position of the control lever clearly indicates the position of the eccentric connector, allowing the user to check the fixture's configuration.

[0064] The grooving system may also include a lever lock to prevent the clamp from accidentally detaching from the inner wall of the pipe.

[0065] The grooving system can be configured as a handheld device. Handheld is understood herein to mean that the grooving system and / or power unit are designed to be held in one hand. The grooving system can have a net weight of approximately 3-10 kg.

[0066] The power unit can be an electric motor. It can also be a handheld drill, possibly a standardized drill. The handheld aspect allows the grooving system to be moved to the pipe and grooving operations to be performed on the installed pipe. The space required for grooving is equal to the size of the grooving system. Compared to existing fixed and manual grooving tools, the invention described herein provides a more flexible and efficient grooving operation.

[0067] A method for forming a groove in a pipe is also described, wherein the method includes the following steps: -Provide a grooving system according to a second aspect of the invention. - Set the control lever to the passive position. - Position the device at the end of the pipe. - Set the control lever to the active position so that the clamp secures the grooving device to the end of the pipe. - The power unit is activated to rotate the wheel retainer around the end of the pipe, while the hydraulic piston moves the wheel retainer from an idle position to a slotted position; and - Continue rotating the wheel retainer around the end of the pipe to complete the grooving.

[0068] A clamp is also described for engaging the inner wall of a pipe end portion and securing the pipe end portion to a device, the clamp comprising: - An axis forming a longitudinal axis coaxial with the central axis of the equipment, which can be axially displaced along the axis in the D1 direction and the opposite D2 direction. - Multiple segments, each segment is radially displaceable between a release position and a fixed position, each segment includes a wedge-shaped inner surface and an outward-facing retaining surface; - A cone, the cone including a conical wedge-shaped surface adjacent to a wedge-shaped inner surface, the cone engaging with a shaft; - A release elastic element, which biases the gripper toward the release position along the axial direction. The axial displacement of the cone relative to the gripper along the D1 direction causes the gripper to move radially outward toward the inner wall, and the axial displacement of the cone relative to the gripper along the D2 direction causes the gripper to move radially inward toward the central axis. The cone may include a tapered central hole, and the cone may slidably engage with the shaft in the tapered central hole. The clamp may include a positioning elastic element that may abut the cone and axially bias the cone along the D1 direction.

[0069] The pipe end portion can form the pipe's central axis. The device can form the device's central axis. The clamp can be configured to secure the pipe end portion to the device such that the clamp's central axis is coaxial with both the pipe's central axis and the device's central axis.

[0070] When the shaft moves along direction D1, the jaws engage with the inner wall of the pipe, and the clamp is in the active / fixed position. When the shaft moves along direction D2, the jaws disengage from the inner wall of the pipe, and the clamp is in the passive / released position.

[0071] The clamp can be configured to radially displace the jaws outward between a release position and a fixed position. The jaws may comprise a rigid material. The jaws may include a gripping surface configured to grip the inner wall of the pipe. The gripping surface may include a grooved surface, a toothed surface, or a serrated surface. A radial force can be used to radially displace the jaws and engage the inner wall, thereby securing the pipe end portion to the device. As the jaws radially displace from the release position to the fixed position, a gap may form between the jaws due to the radial displacement. If the radial force is large compared to the thickness of the pipe, the pipe may deform and form a non-circular shape. For example, a clamp including two jaws can form an elliptical pipe, i.e., a pipe with two protrusions, and a clamp including three jaws can form a pipe with three protrusions, etc.

[0072] The radial displacement of the cone-shaped gripper allows the cone to take advantage of the mechanical benefits associated with the wedge. This reduces the axial force required to securely fasten the end portion of the pipe to the equipment.

[0073] In the fixed position, the gripping surface of the jaws can be part of a full circle, and the fixed position positions the jaws to form an imaginary circumference, which is circular to engage the inner wall of the pipe. The imaginary circumference of the jaws can be similar to or substantially similar to the inner circumference of the pipe wall. The effect of jaws forming a circular imaginary circumference is that pipe deformation is minimized when the clamp engages the inner wall of the pipe. This is important when the clamp is securing the end portion of the pipe while cutting or forming the outer circumference of the pipe near the end. The release position can position the jaws to form a release imaginary circumference, which can be a non-uniform circular circumference. The non-uniform circular circumference can be formed by a ridge near the center of the outer surface of each jaw. Each ridge can have a groove on each side. When the jaws are in the release position, a larger gap can be formed between the inner wall of the pipe and the groove. The larger gap, compared to a circular circumference, makes it easier for the jaws to disengage from the inner wall of the pipe because the groove allows the pipe to swing away from the jaws.

[0074] A control lever can be configured to displace a shaft. The control lever can have a passive position and an active position, wherein the control lever can be locked in the active position via a lever lock. Locking the control lever in the active position ensures that the control lever remains in the active position. This can be important so that the clamp does not accidentally release the pipe when, for example, forming the outer circumference of a pipe with slots. A shaft in a fixed position can be configured to enable the equipment to operate. A shaft in a fixed position can, for example, connect a hydraulic line between a hydraulic pump and the equipment. In the released position, the hydraulic line between the hydraulic pump and the equipment can be disconnected. This improves safety because the equipment may not be started before the shaft is in the active position and the pipe is secured to the equipment.

[0075] The shaft may include a tapered shoulder, and a positioning elastic element may bias the cone such that the cone may be abutted against the tapered shoulder in the release position.

[0076] The clamp may include a first resilient housing fastened to the shaft, and a release resilient element may be biased between the jaws and the first resilient housing.

[0077] The release elastic element biases the gripper toward the release position. The effect is that when the retraction force comes from the release elastic element, the gripper retracts with minimal force from the user. The engagement between the gripper and the adjacent portion can be relatively simple, as the release elastic element positions the gripper in a fixed position along the central axis. The release elastic element can be a coil spring.

[0078] In mass production of pipes, the diameter of the pipe's inner wall can vary. In embodiments where the control lever is configured to displace the cone and thus the gripper to a fixed position, this variation in the inner wall diameter may prevent the control lever from reaching the lever lock. The clamp may include a first resilient housing and a positioning resilient element, the first resilient housing being secured to a shaft, and the positioning resilient element being biased between the cone and the first resilient housing. The positioning resilient element can bias the cone such that the gripper is biased toward the fixed position. The effect is that the cone is allowed axial flexibility, and therefore the gripper has a certain degree of radial flexibility in the fixed position. This flexibility allows for variation in the inner wall diameter when the control lever is locked in the active position. The positioning resilient element may be a single disc spring or multiple stacked disc springs.

[0079] The outer surface of the gripper may include a receiving recess. The recess may be positioned to align with, for example, a grooving device configured to form a groove around the circumference of the pipe. When the grooving wheel presses against the outer surface of the pipe to form a groove, a bulge can be formed inside the pipe. The recess allows grooving to be formed without deforming the gripper or increasing the force required to create the groove.

[0080] The equipment can be a grooving device. It can also be other equipment that may require clamps for engaging the inner walls of pipes.

[0081] Examples of preferred embodiments shown in the accompanying drawings are described below, wherein: Figure 1 A slotting device connected to a handheld drill is shown in a 3D view; Figure 2 A three-dimensional view of the interior of the grooving equipment is shown from the right side; Figure 3 A sectional view of the grooving equipment along the axial direction of AA is shown; Figure 4 A cross-sectional view of the grooving equipment along the axial direction of BB is shown; Figure 5 A cross-sectional view of the grooving equipment along the CC axis is shown; Figure 6 A cross-sectional view of the grooving equipment along DD is shown; Figure 7a -c shows details of the wheel retainer, base plate, and annular hydraulic piston; Figure 8 A sectional view of the grooving equipment along the axial direction of the EE is shown; Figure 9a -b shows cross-sectional views of the slotting equipment along FF and GG at different scales; Figure 10 Exploded views of the shaft and fixture are shown at different scales; Figure 11Axial sectional views of the shaft and fixture are shown at different scales; Figure 12 A cross-sectional view of the clamp along HH is shown; and Figure 13 An enlarged view showing details of the clamp as the cone has slid along the axis is shown.

[0082] For the sake of focusing on the invention, it should be understood that elements such as seals, screws, bolts, nuts, bearings, and bushings may be unnumbered. It should also be understood that all rotating parts may be radially and / or axially supported by one or more bearings. A bearing is understood herein as any element arranged to reduce friction in the rotating parts.

[0083] Figure 1 A grooving device 1 is shown, which is connected to a power unit 9 via a connector 480. The power unit 9 is shown as a handheld drill 90. The connector 480 is configured to mate with a standard handheld drill 90. The central axis of the grooving device is indicated by reference numeral X1. The grooving device 1 and drill 90 shown can be operated with one or two hands. The grooving device 1 shown includes a grooving tool 10, a hydraulic pump and drive mechanism 20, and a clamp 50. The hydraulic pump housing 60 includes a first housing part 601 and a second housing part 602. A control lever 550 is positioned outside the housing 40. The control lever 550 is in a passive position 5502. By rotating the control lever 550 180 degrees, the control lever 550 can be locked in an active position 5504 via a lever lock 560. Figure 2 (best shown in the middle).

[0084] refer to Figure 2 and Figure 4 Input shaft 200 is arranged to connect to handheld drill 90. Input shaft 200 is connected to the first spur gear 201 of a double spur gear 21. The double spur gear 21 includes two second spur gears 202, each of which meshes with the first spur gear 201. Each second spur gear 202 is rotatably rigidly fastened to a corresponding intermediate shaft 202a. In the illustrated embodiment, the second spur gear 202 is a reduction gear because it has more teeth than the first gear 201. A third spur gear 203 is rotatably rigidly fastened to the intermediate shaft 202a. The third spur gear 203 meshes with a fourth spur gear 204. The fourth spur gear 204 is rotatably rigidly fastened to a first end 208 of a drive shaft 207. The drive shaft 207 is offset from the central axis X1 of the slotting device. A fifth spur gear 205 is rotatably rigidly fastened to a second end 209 of the drive shaft 207. The fifth spur gear 205 meshes with the internal teeth of an internal gear ring 206. The internal gear ring 206 is rotatably and rigidly fastened to the base element 120. In the illustrated embodiment, the input shaft 200 is coaxial with the central axis X1 of the grooving device; however, this is not necessary for the operation of the grooving device 1.

[0085] The hydraulic pump and drive mechanism 20 are shown as a dual-power transmission system, meaning that torque is transmitted from the drill 90 to the grooving tool 10 via two drive shafts 207. Alternative embodiments (not shown) may have a single drive shaft 207 or more than two drive shafts 207.

[0086] The control lever 550 is locked in the active position 5504 by the lever lock 560. The control lever 550 is connected to the eccentric connector 552.

[0087] Figure 3 This shows the control lever 550 in the active position 5504 (e.g.) Figure 2 (As shown) the relative passive position 5502. By rotating the control lever 550, the shaft 520 can be moved along the central axis X1 of the grooving equipment to the first position 5202 (as shown). Figure 3 (as shown) and second position 5204 (as shown) Figure 8 The control lever 550 and shaft 520 are connected via an eccentric connector 552. When the control lever 550 rotates to the passive position 5502, the eccentric connector 552 causes the shaft 520 to shift along the second direction D2 to the first position 5202. The control lever 550 is now in the passive position 5502, and the shaft 520 is in the first position 5202. When the control lever 550 reverses, i.e., rotates to the active position 5504, the eccentric connector 552 causes the shaft 520 to shift along the first direction D1 to the second position 5204. The control lever 550 is then in the active position 5504, and the shaft 520 is in the second position 5204.

[0088] refer to Figure 2 , Figure 3 and Figures 8-13 The clamp 50 is arranged to lock the pipe end portion 990 of the pipe 99 to the device 1. The central axis of the pipe is identified by the number X99. The clamp 50 shown includes three jaws 510, which are arranged to engage radially with the inner wall 996 of the pipe 99.

[0089] Fixture 50 and shaft 520 in Figure 10 and Figure 11 The shaft 520 is best shown in the diagram. It includes a connecting portion 5200 at one end and a retaining portion 5209 at the opposite end. From the connecting portion 5200 toward the retaining portion 5209, the shaft 520 includes a connector 5201, a hydraulic portion 521, a tapered portion 523, a resilient portion 525, and a threaded portion 527.

[0090] The diameter of the tapered portion 523 is smaller than the diameter of the hydraulic portion 521. A tapered shoulder 522 is formed between the hydraulic portion 521 and the tapered portion 523. The tapered portion 523 may have a non-circular shape, such as a polygonal geometry, or a spline. The tapered portion 523 may include a key or a ridge. Figure 10 and Figure 12 In the diagram, the conical portion 523 is depicted as having a polygonal geometry, namely a hexagonal geometry.

[0091] The diameter of the elastic portion 525 is smaller than the diameter of the tapered portion 523. An elastic shoulder 524 is formed between the tapered portion 523 and the elastic portion 525.

[0092] The threaded portion 527 may have the same diameter as the elastic portion 523, or it may have a smaller diameter than the elastic portion 523.

[0093] The connector 5201 includes a through hole 5203 adapted to receive the eccentric connector 552 as described above.

[0094] The pipe stop disc 530 has a central portion 531 with a central through opening 532. A section face 533 surrounds the central portion 531. An edge flange 534 surrounds the section face 533. The central portion 531 is offset from the jaw face 533 to form a tapered recess 535. The central through opening 532 has a sufficiently large diameter to allow the shaft 520 to pass through. The section face 533 is closer to the threaded portion 527 than the central portion 531.

[0095] The cone 512 includes a central tapered bore 5123 that matches the geometry of the tapered portion 523. The cone 512 is slidably engaged with the shaft 520. The cone 512 includes a tapered wedge-shaped surface 5121 on its outer side. Figure 10 and Figure 12 Three wedge-shaped surfaces 5121 are depicted. The wedge-shaped surfaces 5121 taper towards the connecting portion 5200. The cone 512 has a minimum diameter facing the tube stop disc 530, and the minimum diameter of the cone 512 fits into the central portion 531, as shown. Figure 4 , Figure 8 and Figure 13 As shown. Each wedge-shaped surface 5121 is provided with an outwardly protruding guide 5122 along the longitudinal direction. The guide 5122 is shown as a T-shaped guide 5124, as... Figure 10 and Figure 12 As shown. The longitudinal length of the cone 522 corresponds to the length of the cone portion 523.

[0096] Each wedge-shaped surface 5121 and its corresponding guides 5122, 5124 mate with a jaw 510. Each jaw 510 is fan-shaped, having an arcuate outer surface 511 and a wedge-shaped inner surface 517. The arcuate outer surface 511 includes a receiving recess 515 and a retaining surface 516. The retaining surface 516 is shown as a rough retaining surface 516 for better gripping. The retaining surface 516 has a larger diameter than the receiving recess 515, and the outer surface 511 is stepped. The wedge-shaped inner surface 517 tapers toward the threaded portion 527. The wedge-shaped inner surface 517 includes a slot 5172 in the longitudinal direction that mates with the outwardly projecting guide 5122. The slot 5172 may mate with a T-shaped guide 5124 (see [link to documentation]). Figure 12 The T-shaped slot 5174. The relative movement of the gripper 510 along the longitudinal direction of the cone 512 provides radial movement of the gripper 510.

[0097] The second resilient housing 518 surrounds the shaft 520. The resilient housing 518 is provided with an inwardly projecting edge 5181, which forms a central housing hole 5183. The edge 5181 abuts the jaw end face 5109 of the gripper 510, as shown below. Figure 11 As shown. The central housing bore 5183 has a diameter that allows the tapered end face 5129 to enter the resilient housing 518, see [reference]. Figure 3 , Figure 11 and Figure 13 .

[0098] A positioning elastic element 514 surrounds the elastic portion 525. In the illustrated embodiment, the positioning elastic element 514 is a plurality of disc springs coaxially positioned with respect to the shaft 520. A release elastic element 513 surrounds the elastic portion 525 on the outside of the positioning elastic element 514.

[0099] The first elastic housing 519 of the thread houses the positioning elastic element 514, the release elastic element 513, and the second elastic housing 518, as shown below. Figure 11 and 13 As shown in the optimal configuration. The first resilient housing 519 is fastened to the shaft 520 in the threaded portion 527. The lock nut 5190 secures the first resilient housing to the shaft 520.

[0100] The positioning elastic element 514 is biased between the inner surface 5191 of the first elastic housing 519 and the elastic shoulder 524 and / or the tapered end face 5129 (see [link]). Figure 11 and Figure 13The positioning elastic element 514 abuts the tapered end face 5129. The release elastic element 513 is biased between the inner surface 5191 and the edge 5181 of the first elastic housing 519, and when the control lever 550 is in the passive position 5502 and the shaft 520 is in the first position 5202, the cone 512 abuts the tapered shoulder 522. The elastic shoulder 524 is flush with the tapered end face 5129. Therefore, the positioning elastic element 514 abuts both the elastic shoulder 524 and the tapered end face 5129, as shown. Figure 3 and Figure 11 As shown. The pipe stop disc 530 is fastened to the piston housing 13, and the edge flange 534 rests on the corresponding step of the piston housing 13, as shown. Figure 3 and Figure 4 As shown. The tube stop disc 530 is stationary relative to the piston housing 13, and the shaft 520 is axially movable within the piston housing 13. When the shaft 520 is in the first position 5202, each jaw 510 abuts the segment 533 at the jaw sliding end face 5108, which is opposite to the jaw end face 5109. The release elastic element 513 acts on the tube stop disc 530 at one end through the jaw 510 and the edge 5181, and acts on the first elastic housing 519 at the opposite end. Thus, the release elastic element 513 generates an axial force in the second direction D2 and pushes the shaft 520 in the D2 direction. As a result, the jaw 510 moves inward toward the central axis X1, as... Figure 3 and Figure 11 As shown.

[0101] Pipe 99 is pushed into inlet 130 of piston housing 13 until pipe 99 is adjacent to pipe stop plate 530.

[0102] When shaft 520 moves along the first direction D1 to the second position 5204 (e.g.) Figure 8 As shown), the positioning elastic element 514 biases the cone 512 against the conical shoulder 522, causing the cone 512 to follow the movement of the shaft 520. Figure 8 As shown, when the wedge-shaped inner surface 517 slides against the conical wedge-shaped surface 5121, the gripper 510 is pressed radially outward until the retaining surface 516 is adjacent to the inner wall 996 of the pipe 99.

[0103] The distance the cone 512 shifts between the first position 5202 and the second position 5204 via the shaft 520 is fixed. The radial displacement of the gripper 510 is also fixed as long as the cone 512 does not slide along the shaft 520. The cone 512 and gripper 510 are sized to mate with a known pipe 99 having a known inner diameter. If the inner diameter is not uniform, or the wall thickness of the pipe 99 is greater than expected, resulting in an inner diameter smaller than expected, then with the cone 512 fixed to the shaft 520, the gripper 510 abuts the inner wall 996 before the control lever 550 reaches the lever lock 560. However, according to this disclosure, if the inner diameter is not uniform, or the wall thickness of the pipe 99 is greater than expected, the cone 512 slides along the tapered portion 523. The cone 512 no longer abuts the tapered shoulder 522, and the tapered end face 5129 is no longer flush with the elastic shoulder 524. Figure 13 As shown, the positioning elastic element 514 abuts against the tapered end face 5129 and biases the cone 512 toward the connector. Therefore, even if the inner diameter is smaller than expected and the control lever 550 reaches the lever lock 560, the gripper 510 still presses outward toward the inner wall 996 with sufficient force to keep the pipe 99 stable.

[0104] The control lever 550 is secured in the active position 5504 by lever lock 560, so that the gripper 510 is held in the locked position.

[0105] When axis 520 moves along the second direction D2 to the first position 5202 (as shown in the image) Figure 3 As shown), the gripper 510 retracts radially inward, supported by the release elastic element 513 biased along the first direction D1, thereby moving radially inward toward the central axis X1 of the grooving equipment as the cone 512 moves along the second direction D2. Figure 3 As shown, when the shaft is in the first position 5202, the clamp 50 does not engage with the inner wall 996 of the pipe 99.

[0106] In a plane perpendicular to the central axis X1, the connector 5201 has a non-circular shape. Figure 9a In the diagram, connector 5201 is shown as having an elliptical circumference. Connector 5201 is positioned within a cavity 41 of a complementary shape in housing 40. Connector 5201 is axially displaceable within cavity 41, such as... Figure 4 and Figure 8 As shown. Connector 5201 and shaft 520 cannot rotate around the central axis X1, as... Figure 9a As shown.

[0107] Shaft 520 has three functions. Shaft 520 serves as an actuator for clamp 50. Shaft 520 transmits torque from pipe 99 to housing 40, thereby preventing pipe 99 from rotating during slotting. Shaft 520 serves as a sliding valve in hydraulic system 6, as will be described below.

[0108] Now for reference Figure 3 and Figure 8 The receiving recess 515 is positioned to align with the slotted wheel 111. (Refer to...) Figure 4 The grooving wheel 111 is described in more detail. When the grooving wheel 111 presses against the outer surface of the pipe 99 to form a groove 994, a bulge 995 is formed inside the pipe 99.

[0109] Now for reference Figure 3 and Figure 4 The hydraulic pump and drive mechanism 20 includes a hydraulic system 6. The hydraulic system 6 includes a volume-compensated fluid reservoir 630. The volume-compensated fluid reservoir 630 includes a rigid housing 6302. The rigid housing 6302 includes a housing 40, a flange portion 19, and a pump housing 60. The volume-compensated fluid reservoir 630 is sealed to the environment 6305 surrounding the grooving tool 1. The rigid housing 6302 includes a through-hole 6303. An inflatable / deflatable device 6301 is connected to the through-hole 6303 such that the inflatable / deflatable device 6301 is positioned within the rigid housing 6302 and fluidly connected to the environment 6305. In the illustrated embodiment, the inflatable / deflatable device 6301 is a flexible bladder. The through-hole 6303 is positioned adjacent to an internal portion of the grooving tool 10. A tank line 6306 connects the volume-compensated fluid reservoir 630 to the hydraulic pump housing 60. The storage tank line 6306 is from the outlet of the volume-compensated fluid reservoir 630, where the stored fluid 69 is stored.

[0110] The first gear pump 61 and the second gear pump 62 are positioned within the hydraulic pump housing 60, such as Figure 4 and Figure 6 As shown. The first gear pump 61 includes a third spur gear 203 and a fourth spur gear 204. The third spur gear 203 serves as the first pump gear in the first gear pump 61, and the fourth spur gear 204 serves as the second pump gear in the first gear pump 61. The second gear pump 62 includes a third spur gear 203 and a fourth spur gear 204. The third spur gear 203 serves as the first pump gear in the second gear pump 62, and the fourth spur gear 204 serves as the second pump gear in the second gear pump 62. The first gear pump 61 and the second gear pump 62 are connected in parallel. One side of the first gear pump 61 and one side of the second gear pump 62 are connected to a storage tank line 6306. The opposite side of the first gear pump 61 and the opposite side of the second gear pump 62 are connected to a pressure line 632, so that hydraulic fluid flow and hydraulic pressure can be provided within the pressure line 632. The pressure line 632 is connected to a flow restrictor 639 (e.g., Figure 9b (as shown) and pressure reducing valve 68 (as shown) Figure 9b(As shown). Pressure reducing valve 68 is fluidly connected to volume-compensated fluid reservoir 630. Flow restrictor 639 can be adjustable, which allows for adjustment of the displacement rate of wheel retainer 110. An excessively fast displacement rate increases friction on the grooving wheel 111, preventing it from rolling as intended. An excessively slow displacement rate results in no bulge 995 being formed because the material does not shift as expected during the grooving operation.

[0111] Pressure line 632 is arranged to connect the first gear pump 61 and the second gear pump 62 to the first hydraulic rotary coupling 640 (in Figure 4 (Best shown in the diagram). Shaft 520 includes a shaft return line 6308 and a shaft pressure line 6322. Shaft return line 6308 is in fluid communication with volume-compensated fluid reservoir 630 via a return line 64 connected to volume-compensated fluid reservoir 630. Shaft return line 6308 may be connected to a first hydraulic rotary connector 640 and a second hydraulic rotary connector 650. Shaft pressure line 6322 may be connected to the first hydraulic rotary connector 640 and the second hydraulic rotary connector 650. Hydraulic lines connected to hydraulic rotary connectors are described herein as allowing hydraulic fluid to flow from the hydraulic lines and through the hydraulic rotary connectors. Hydraulic lines disconnected from hydraulic rotary connectors are described herein as preventing hydraulic fluid from flowing from the hydraulic lines and through the hydraulic rotary connectors.

[0112] The first hydraulic rotary connector 640 is configured such that the shaft 520 can rotate about and displace along the central axis X1 of the equipment. The second hydraulic rotary connector 650 is configured such that the shaft 520 can rotate about and displace along the central axis X1 of the equipment on the inner surface 6502 of the second hydraulic rotary connector 650. The second hydraulic rotary connector 650 is configured such that the base element 120 can rotate around the outer surface 6504 of the second hydraulic rotary connector 650 about the central axis X1 of the equipment.

[0113] With shaft 520 in the first position 5202, the first hydraulic rotary connector 640 connects pressure line 632 to shaft return line 6308. The second hydraulic rotary connector 650 connects shaft return line 6308 to grooving tool hydraulic line 634. Grooving tool hydraulic line 634 is arranged to connect piston chamber 14 to the second hydraulic rotary connector 650, in which an annular hydraulic piston 12 is positioned. When shaft 520 is in the first position 5202, shaft pressure line 6322 is disconnected from the first and second hydraulic rotary connectors 640 and 650. Thus, shaft 520 in the first position 5202 connects the first gear pump 61, the second gear pump 62, and piston chamber 14 to volume-compensated fluid reservoir 630 via return line 64.

[0114] With shaft 520 in the second position 5204, the first hydraulic rotary connector 640 connects pressure line 632 to shaft pressure line 6322, and the second hydraulic rotary connector 650 connects shaft pressure line 6322 to grooving tool hydraulic line 634. Shaft return line 6308 is disconnected from the first hydraulic rotary connector 640 and the second hydraulic rotary connector 650. Therefore, in the second position 5204, shaft return line 6308 is connected only to volume-compensated fluid reservoir 630. Thus, shaft 520 in the second position 5204 connects the first gear pump 61 and the second gear pump 62 to piston chamber 14.

[0115] refer to Figure 2 and Figure 4 The grooving tool 10 is arranged relative to the housing 40 and rotates about the central axis X1 of the device. As previously described, the internal gear ring 206 is rotatably rigidly fastened to the base element 120, thus the drive shaft 207 and the fifth spur gear 205 are configured to rotate the grooving tool 10 about the central axis X1 of the device. (Reference) Figure 4 , Figure 7a and Figure 8 The grooving tool 10 includes a plurality of wheel retainers 110. Each wheel retainer 110 includes a grooving wheel 111 on a wheel axle 113. The illustrated embodiment is shown with three wheel retainers 110. The grooving wheel 111 has a smaller diameter 1112 on each side of the ridge 112, and this diameter is arranged to limit the inward radial movement of the grooving wheel 111 during the grooving operation when the grooving wheel 111 forms a groove 994 in the pipe 99 (e.g., Figure 8 (As shown). An additional effect of the smaller diameter 1112 is that it prevents the pipe end portion 990 extending from the slot 994 from radially rising or bending during the slotting operation.

[0116] Each wheel retainer 110 is connected to the base element 120 and can be in the idle position 1102 (e.g. Figure 3 and Figure 4 (as shown) and slot location 1104 (as shown) Figure 8 Radial displacement between (as shown). The idle position 1102 is easily identified by the bias of the hydraulic piston 12 toward the starting position 141 within the piston chamber 14. Displacement of the hydraulic piston 12 from the starting position 141 to the intermediate position 145 within the piston chamber 14 causes the wheel retainer 110 to shift to the slotted position 1104. Now refer to Figure 5 and 7a -b. The wheel retainer 110 includes two protrusions 1106 arranged to engage with corresponding slots 1202 in the base element 120. The corresponding slots 1202 are in... Figure 7b The middle part is indicated by a dashed line. Figure 5The corresponding groove 1202 can also be seen in the middle. The protrusion 1106 and the corresponding groove 1202 are arranged radially toward the central axis X1 of the grooving equipment.

[0117] Wheel retainer 110 is connected to hydraulic piston 12. Wheel retainer 110 is radially displaced by axial displacement of hydraulic piston 12. In the illustrated embodiment, wheel retainer 110 includes four protrusions 114 on each side of wheel retainer 110 (see [reference]). Figure 2 and 7a There are two protrusions 114. The protrusions 114 are arranged to engage with corresponding recesses 121 in the hydraulic piston 12. The recesses 121 form an angle with the central axis X1 of the equipment (in...). Figure 3 and Figure 7c (Best shown in the diagram). Therefore, the protrusion 1106, the corresponding groove 1202, the protrusion 114, and the recess 121 are arranged such that when the hydraulic piston 12 is displaced along the first direction D1, the wheel retainer 110 is radially displaced toward the central axis X1 of the device. The radial displacement depends on the angle between the protrusion 114 and the recess 121 and the central axis X1 of the device. As a non-limiting example, a 10 mm displacement of the hydraulic piston along the first direction D1 corresponds to a 2.5 mm radial displacement of the wheel retainer 110. The hydraulic piston 12 can be displaced along the first direction D1 by filling the piston chamber 14 with hydraulic fluid 69. The hydraulic piston 12 is displaced by a plurality of springs 16 (in... Figure 5 (Best shown in the diagram) biased toward the second direction D2. In the illustrated embodiment, spring 16 is shown as a helical spring.

[0118] Figure 9a -b shows the first plug 638 for a volume-compensated fluid reservoir 630 filled with hydraulic fluid 69.

[0119] The hydraulic system 6 can be filled with hydraulic fluid 69. The filling process includes the following steps: -Remove the first plug 638; - Fill the volume-compensated fluid reservoir 630 with hydraulic fluid 69 until the volume-compensated fluid reservoir 630 is full; - Assemble the first plug 638 to seal and isolate the volume-compensated fluid reservoir 630 from the environment 6305 surrounding the slotted equipment 1.

[0120] The power unit 9 of a handheld drilling rig 90 is via, for example, Figure 1 The connector 480 shown is connected to the grooving device 1. The grooving device 1 is connected to the pipe end portion 990 of the pipe 99. By moving the control lever 550 from the passive position 5502 to the active position 5504, the pipe 99 is locked to the grooving device 1. Figure 2As shown, the control lever 550 is secured by the lever lock 560. Therefore, the clamp 50 secures the pipe 99 as previously described.

[0121] The handheld drill 90 rotates the grooving tool 10 by activating the hydraulic pump and drive mechanism 20. A first gear pump 61 and a second gear pump 62 operate in parallel, increasing the hydraulic pressure to, for illustrative purposes, 10 bar. A pressure reducing valve 68 can be set to, for example, 10 bar. The hydraulic pressure is delivered to the piston chamber 14 and acts on the hydraulic piston 12. The hydraulic pressure is delivered through pressure line 632, first hydraulic rotary connector 640, axial pressure line 6322, second hydraulic rotary connector 650, and grooving tool hydraulic line 634, and then to 10 bar. Due to the flow restrictor 639 and multiple springs 16, the hydraulic piston 12 slowly moves within the piston chamber 14 along and parallel to the central axis X1 of the grooving device. Thus, as the grooving wheel 111 rotates around the pipe 99, the wheel retainer 110 slowly and radially inwards, and the grooving wheel 111 slowly forms a groove 994 in the outer surface of the pipe 99. As hydraulic fluid 69 shifts from the volume-compensated fluid reservoir 630 into the piston chamber 14, the inflatable / deflatable device 6301 is inflated with air from the surrounding environment 6305 of the slotting device 1. The inflatable / deflatable device 6301 is inflated with the same volume as used to shift the hydraulic piston 12.

[0122] Drilling 90 can be stopped at the end of the piston stroke and / or when the smaller diameter 1112 adjacent pipe 99, i.e., when slotting 994 is completed. Drilling 90 can be stopped when control lever 550 moves to the passive position 5502 (see...). Figure 1 , Figure 3 and Figure 5 When the hydraulic fluid 69 in piston chamber 14 is directed to volume-compensated fluid reservoir 630, spring 16 forces hydraulic piston 12 back to starting position 141. Consequently, wheel retainer 110 and slotted wheel 111 return to idle position 1102. When hydraulic fluid 69 returns from piston chamber 14 to volume-compensated fluid reservoir 630, inflatable / deflate device 6301 deflates to the state prior to the displacement of hydraulic piston 12.

[0123] The smaller diameter 1112 of the grooving wheel 111 ensures that the pipe end 991 remains straight during the grooving operation, and the grooving 994 is made to a predetermined depth. The predetermined depth is determined by the radial difference between the smaller diameter 1112 and the ridge 112.

[0124] The fourth spur gear 204 of the first gear pump 61 rotates the connected drive shaft 207. The drive shaft 207 rotates the fifth spur gear 205, thereby rotating the internal gear ring 206. The fourth spur gear 204 of the second gear pump 62 is connected to the internal gear ring 206 in the same manner. The base element 120 is fixed to the internal gear ring 206, as shown below. Figure 2 As shown. Therefore, when the control lever 550 is in the active position 5504 and the power unit 9 is activated, this activates the hydraulic pump and drive mechanism 20. Consequently, the slotting wheel 111 slowly and radially inwardly moves into the pipe 99, while simultaneously rolling the slotting wheel 111 around the entire circumference of the pipe 99.

[0125] It should be noted that the above embodiments are illustrative rather than limiting of the invention, and those skilled in the art will be able to devise many alternative embodiments without departing from the scope of the appended claims. Any reference numerals placed between parentheses in the claims should not be construed as limiting the claims. The use of the verb "comprising" and its variations does not exclude the presence of elements or steps other than those described in the claims. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0126] The mere fact that certain measures are described in mutually different dependent claims does not indicate that combinations of these measures cannot be used advantageously.

Claims

1. A grooving device (1) arranged for rolling a circumferentially outward grooving (994) at a pipe end portion (990), the grooving device (1) forming a central axis (X1), the grooving device (1) comprising a clamp (50) and a grooving tool (10), the clamp (50) being configurable between a release position and a fixed position, wherein in the fixed position the clamp (50) is configured to engage the inner wall (996) of the pipe (99) and fix the grooving device (1) to the pipe end portion (990) such that the pipe central axis (X99) is coaxial with the central axis (X1), and the grooving tool (10) is rotatable about the central axis (X1), characterized in that: - The grooving tool (10) includes a hydraulic piston (12) and at least one wheel retainer (110). - The hydraulic piston (12) is capable of displacement along the central axis (X1); The hydraulic piston (12) is configured to shift the wheel retainer (110) radially relative to the central axis (X1) between an idle position (1102) and a slotted position (1104); and - The wheel retainer (110) includes a slotted wheel (111).

2. The grooving equipment (1) according to claim 1, wherein, The grooving device (1) includes at least three wheel retainers (110).

3. The grooving equipment (1) according to any one of claims 1 and 2, wherein, The grooving tool (10) includes a base element (120), and the wheel retainer (110) is radially displaceable to the base element (120).

4. The grooving device (1) according to any one of the preceding claims, wherein, The grooving device (1) is configured to receive rotational force from a drive shaft (207) that is offset from the central axis (X1).

5. The grooving device (1) according to any one of the preceding claims, wherein, The grooving device (1) is configured to receive hydraulic fluid (69) from the pressure line (632).

6. The grooving equipment (1) according to claim 4, wherein, The grooving tool (10) includes an internal gear ring (206).

7. The grooving device (1) according to any one of the preceding claims, wherein, The hydraulic piston (12) is biased toward the starting position (141).

8. The grooving device (1) according to any one of the preceding claims, wherein, The clamp (50) can be configured by shifting the shaft (520) parallel to the central axis (X1).

9. The grooving device (1) according to any one of the preceding claims, wherein, The rotational force and the hydraulic fluid flow are provided by a battery-powered power unit (90).

10. A grooving system arranged for rolling a circumferentially external grooving (994) at a pipe end portion (990), characterized in that: -The grooving system includes the grooving device (1) according to any one of claims 1 to 9; - The grooving system includes a hydraulic pump and drive mechanism (20), a fluid reservoir (630), and a clamp (50); - The hydraulic pump and drive mechanism (20) are configured to be connected to the power unit (9) and receive rotational force from the power unit (9) via the input shaft (200); - The hydraulic pump and drive mechanism (20) are configured to generate an output, which includes a hydraulic fluid flow and a rotational force, and the output is transmitted to the grooving device (1). - The fixture (50) forms a central axis, which is coaxial with the central axis (X1) of the grooving tool; and - The clamp (50) is configured to engage the inner wall (996) of the pipe (99) and secure the pipe end portion (990) to the slotting device (1).

11. The grooving system according to claim 10, wherein, The grooving system is designed to be handheld.

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