83 results about "Pipe wrench" patented technology

The utility model relates to the technical field of finish machining of large rotary tables of boring and milling machines, in particular to an adjustable equal-height sizing block for machining a large rotary table. The device comprises a plurality of equal-height sizing blocks which are fixedly mounted on the table top of the large rotary table; the equal-height sizing block comprises an upper seat body, the upper seat body is connected with a lower seat body, cover plates are installed on the outer side of the upper seat body and the outer side of the lower seat body, a copper flange is installed at the top end of the upper seat body, the copper flange is connected with the upper seat body, a jacking column is installed in the upper seat body, a limiting block is installed at the bottom end of the outer side of the lower seat body, and a wedge block is installed at the bottom end in the lower seat body. A wedge block is arranged at the bottom end of the jacking column, one side of the wedge block is the inner wall of the lower seat body, a hexagon screw is installed on the other side of the wedge block, the other side of the hexagon screw is connected with a lengthened sleeve wrench, a sleeve wrench support is arranged at the bottom end of the lengthened sleeve wrench, and the bottom end of the sleeve wrench support is the ground. The equal-height sizing block provided by the utility model not only has the same height in the original state, but also can ensure the same height in real time, so that the labor intensity of an operator is effectively reduced.

The invention relates to the technical field of oil pipe wrenches, and particularly discloses an anti-skid oil pipe wrench suitable for an oil contamination environment, which comprises a fixed base, an upper clamping plate is slidably connected to the side surface of the fixed base, an upper handle is fixedly connected to the side surface of the fixed base, and a clamping device is fixedly connected to the center position of the side surface of the fixed base. A lower clamping plate is slidably connected to the position, located below the upper clamping plate, of the side face of the fixing base, an upper supporting base is rotatably connected to the bottom of the fixing frame, an upper sliding strip is fixedly connected to the position, located on one side of the upper supporting base, of the bottom of the fixing frame, and an upper rack is fixedly connected to the center of the bottom of the upper base; the side face of the upper base is slidably connected with the side face of the fixed base, the side face of the upper rack is meshed with the side face of the clamping device, and the anti-skid oil pipe wrench suitable for the oil contamination environment achieves the purpose of preventing grease from sliding and being difficult to rotate.

A torque slider tong assembly provides a safe, convenient, light weight, portable, hand-operable dual pipe wrench for use in makeup and breakout of tubular connections. The torque-slider tong assembly includes a backup arm forming a first pipe wrench gripping a first pipe, a torque arm forming a second pipe wrench gripping a second pipe, and an actuator providing motive force moving the torque arm relative to the backup arm transverse to the pipes, which rotates the pipes relative to each other. A torque slider adjustably connects the actuator to the backup arm to adjust the mechanical advantage between the backup arm and the torque arm providing additional setup flexibility. Similarly, a movable pivot point, such as a clevis, adjustably connects the actuator to the torque arm providing additional setup flexibility. Quick-change pins allow positional adjustment of multiple components.

A capped bamboo-joint screw includes a screw body with a set of threaded grooves and a set of unthreaded areas on its outer surface. An adapter post is connected to the left side of the screw body, and a nut is connected to the left side of the adapter post. This device utilizes the alternating distribution of threaded grooves and unthreaded areas. When adjusting the screw length, the user can use pipe wrenches or wire cutters to clamp the unthreaded area and precisely cut it off along a preset break point. The threaded grooves remain intact after cutting, not affecting subsequent threaded connections with nuts or installation components, greatly expanding the length adaptability range and reducing the need for stock specifications. Simultaneously, the Phillips head groove on the left side of the nut, in conjunction with the adapter post, ensures that torque is effectively transmitted to the threaded section when tightening the screw with tools, enhancing installation stability. Furthermore, the integrated metal cap design makes this product aesthetically pleasing and provides excellent protection.

The utility model provides a multifunctional fire-fighting wrench, which relates to the technical field of fire-fighting instruments and comprises a fire hydrant wrench, the fire hydrant wrench comprises an open wrench, an inner pentagonal sleeve and a wrench body, the inner pentagonal sleeve and the open wrench are arranged at the front end of the wrench body, a pipe wrench is arranged at the tail end of the wrench body, and a sleeve component is fixedly arranged on the wrench body. According to the fire hydrant wrench, the pipe wrench and the sleeve assembly are arranged on the fire hydrant wrench, so that the fire hydrant wrench with a single function has other functions, the sleeve head of the sleeve assembly can be replaced, and the sleeve head can be replaced according to actual requirements; the outdoor fire hydrant blank cap and the outdoor water suction pipe blank cap can be opened, closed, repaired and maintained only through a small number of tools, carrying is convenient, working efficiency is high, rescue of a fire scene is facilitated, and the effect of saving time and labor is achieved.

1. The name of the design product: the pipe pliers (the mouth pliers, the force pliers). 2. The use of the design product: special-shaped / circular workpiece clamping positioning, accurate fixing of workpiece position in welding (such as spot welding, argon arc welding) operation, avoiding displacement during welding. 3. The design points of the design product: in shape. 4. The picture or photo that can best show the design points: perspective view.

A pipe wrench is provided, wherein the pipe wrench includes: a first clamp body including a first handle portion, a first clamping portion and a body portion connected between the first handle portion and the first clamping portion, the body portion including a guide groove having a tooth row; a second clamp body including a second handle portion, a second clamping portion and a pivot hole; and a button inserted in the guide groove and the pivot hole, including a button base, a toothed member and an elastic member disposed between the button base and the toothed member, the button base being movable relative to the guide groove to disengage the toothed member from the tooth row, the toothed member being movable relative to the button base in a radial direction of the button and releasably engaged with the tooth row.

The utility model discloses a mud cleaning tool for a logging cable, and belongs to the technical field of logging instruments. The mud cleaning tool for the logging cable comprises two sponge blocks arranged in a port of a hydraulic pipe twisting machine, the hydraulic pipe twisting machine is arranged at a wellhead of a detection well, a first hook-and-loop fastener is arranged between the inner side wall of the hydraulic pipe twisting machine and the sponge blocks, and the first hook-and-loop fastener comprises a first rough surface adhered to the inner side wall of the hydraulic pipe twisting machine and a second rough surface adhered to the outer side wall of the hydraulic pipe twisting machine. The cable fixing device comprises two sponge blocks and first smooth surfaces adhered to the outer surfaces of the sponge blocks, a second magic tape is arranged between the two sponge blocks, the second magic tape comprises a second rough surface fixed to one sponge block and a second smooth surface fixed to the other sponge block, and a cable penetrates through the space between the two sponge blocks. According to the utility model, on one hand, the cable slurry cleaning device plays a role in cleaning cable slurry, and on the other hand, plays a role in protecting the cable, prevents the cable from being abraded with the port of the hydraulic pipe twisting machine when the cable is lifted upwards, and protects the cable.

1. Name of the product in this design: Pipe wrench (new German style). 2. Purpose of this design: For the assembly and disassembly of pipes. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: a 3D model.

The utility model discloses a tool for quickly disassembling a casing thread protector, which comprises a base, a central screw rod is fixedly connected to the center of the base, and an upper end cover is sleeved on the central screw rod in a threaded manner; the edge of the upper end cover is evenly connected with a plurality of lug plates in the circumferential direction, and the lower ends of the lug plates are connected with tooth plates. The utility model successfully solves the problems of high labor intensity, low working efficiency and the like when a single person or multiple persons use tools such as a pipe wrench, an F-shaped wrench, a crowbar, a hammer and the like to disassemble the casing thread protector in the drilling and workover period. And major safety risks caused by injury accidents due to poor communication or wrong matching when a plurality of persons cooperate with each other to disassemble the casing thread protector are solved. The dismounting tool can be used for rapidly and conveniently dismounting the casing thread protector, is strong in adaptive capacity, and can be suitable for dismounting the casing thread protector with the size range of 6 ''-10'', so that the dismounting operation of the casing thread protector is safer, more convenient and more efficient.

The utility model discloses a hydraulic energy-saving system of a pipe screwing machine, which relates to the technical field of hydraulic systems and comprises a hydraulic oil tank of the pipe screwing machine, a hydraulic oil pump, an oil inlet pipe, an oil outlet pipe, an oil suction pipe and an oil return pipe, the hydraulic oil pump is mounted on the hydraulic oil tank of the pipe screwing machine, and an oil inlet of the hydraulic oil pump is connected with the oil suction pipe arranged in the hydraulic oil tank of the pipe screwing machine. The heat dissipation structure is arranged on the surface of the hydraulic oil tank of the pipe screwing machine, the effective heat dissipation area of the hydraulic oil tank of the pipe screwing machine can be increased, heat in the hydraulic oil tank can be rapidly dissipated through natural heat dissipation, meanwhile, the heat dissipation fan is installed right in front of the heat dissipation structure, the heat dissipation effect is good, and the heat dissipation effect is good. According to the hydraulic energy-saving system of the pipe screwing machine, the flowing speed of air around the heat dissipation structure can be increased, heat on the heat dissipation structure can be rapidly conducted into the surrounding air, and therefore the heat dissipation efficiency of the hydraulic energy-saving system of the pipe screwing machine can be further improved, and the energy-saving effect is achieved.

The utility model relates to auxiliary equipment for tunnel mounting ring and longitudinal blind pipe construction, in particular to a pipe wrench device for fixing a tunnel waterproof plate. Comprising an arc-shaped clamping ring with a notch and an X-shaped connecting rod, the clamping ring comprises a left half arc-shaped clamping ring and a right half arc-shaped clamping ring which are symmetrical to each other, the connecting rod comprises a left connecting straight rod and a right connecting straight rod, and the left half arc-shaped clamping ring and the right connecting straight rod form a whole A; the right half arc-shaped clamping ring and the left connecting straight rod form a whole body B, and the round connecting parts of the whole body A and the whole body B are hinged together through an articulated shaft which is inserted in the whole body A and the whole body B; flat plates are welded to the ends, away from the hinge shaft, of the left half arc-shaped clamping ring and the right half arc-shaped clamping ring correspondingly; when the waterproof plate is laid to the position of the annular blind pipe, the waterproof plate is difficult to be tightly attached by being pressed manually, and the waterproof plate can be better tightly attached to the blind pipe and the primary supporting face with the assistance of the pipe wrench. And the phenomenon that the lining concrete is not compact at the weak disengaging position of the laid blind pipe is avoided.

The utility model discloses a pair of mining hydraulic high-pressure pipeline pin-removing and pipe-drawing pliers, which comprises a hand pump, the front end of the hand pump is provided and communicated with the hand pump, the output end of the hand pump is provided with telescopic inclined iron, one end of the hand pump, which is provided with the telescopic inclined iron, is rotatably provided with a pipe pressing mechanism and a supporting mechanism, and the telescopic inclined iron is positioned between the pipe pressing mechanism and the supporting mechanism; the pipe pressing mechanism comprises a supporting block, one end of the supporting block is hinged to the end face of the hand pump, the other end of the supporting block is fixedly connected with a hoop, an adjusting bolt penetrates through the hoop in a threaded mode, the end, in the hoop, of the adjusting bolt is fixedly connected with a movable clamping block, and the lower end of the supporting block is an inclined face and makes contact with the inclined face of the upper portion of the telescopic inclined iron in a matched mode. According to the device, the hand pump principle and the slope principle are utilized, the high-pressure pipe is automatically pulled out, the labor intensity and the safety risk are reduced, the pipe pressing mechanism and the supporting mechanism are both designed to be adjustable, the device can adapt to high-pressure pipes and connectors of different models, and the universality and practicability of the device are improved.

The utility model discloses a simple special pipe wrench for an air shield dam, which is characterized in that a pipe wrench is provided with a metal cylinder, the upper section of the metal cylinder is provided with a pipe wrench circular force application hole which is vertical and penetrates through the metal cylinder, and the lower section of the metal cylinder is connected with an outer-circle inner-hexagonal pipe wrench head; when the anchoring bolt cap of the air shield dam is installed and constructed, the special pipe wrench for the air shield dam is vertically and downwards sleeved on the bolt cap, then a force application rod with enough strength is inserted into the force application hole of the pipe wrench, and the round rod is rotated to screw the anchoring bolt cap. The simple wrench for the special pipe of the air shield dam is scientific and reasonable in design, simple in structure, easy to manufacture and convenient and easy to use, and solves the installation problem of a large-diameter and large-torque extra-long anchor bolt cap of the air shield dam.

The invention relates to a drill rod clamping and pipe screwing device, which relates to the technical field of drill rod tripping equipment, and comprises a rack, which is vertically provided with a through hole for a drill rod to pass through in a penetrating manner; the clamp holder assembly is fixedly mounted on the rack and is used for clamping a next drill rod; the pipe twisting device assembly is positioned above the clamping device assembly; one end of the pipe screwing seat is fixedly connected to the inner side of the pipe screwing gear ring, the pipe screwing seat is connected to the rack in a sliding mode, the hoop is connected to the other end of the pipe screwing seat in a sliding mode, the driving end of the pipe screwing driving piece is connected to the pipe screwing gear ring in a transmission mode, and the hoop is used for clamping a previous drill pipe. By the adoption of the technical scheme, clamping and pipe screwing operation of the drill rod can be smoothly achieved, and the probability of personnel injury is reduced.

A kind of main tong transmission device of pipe wrench, including control system, including transmission case, the inside of which is provided with shaft coupling II, one end of the shaft coupling II is fixedly connected with speed reducer shaft, the other end is fixedly connected with power gear shaft;The outer edge of the power box is provided with speed reducer, the speed reducer one end is connected with motor by shaft coupling I, and speed reducer shaft is fixedly connected by shaft coupling II and power gear shaft;Main tong internal power gear is installed on power gear shaft and engages with idler gear, and the idler gear engages with large gear ring;Motor and control system are electrically connected.The utility model discloses by adjusting the rotating speed of motor to control the fast and slow of main tong clamping device screwing speed, has realized the stepless regulation between high speed and low speed when pipe joint thread is screwed, avoids the phenomenon that screwing torque breaks through torque upper limit and over-tightens, while the actual demand of low speed large torque and high speed small torque in the process of screwing can be realized, protects thread, improves work efficiency.

The utility model discloses a pipe wrench assembly and an iron roughneck device, and relates to the technical field of iron roughneck devices, the pipe wrench assembly comprises a fixing frame, a fixed rotating wrench assembly, a movable rotating wrench assembly, a rotating wrench separating and combining mechanism and a power mechanism, the fixed rotating wrench assembly is fixedly installed on the fixing frame; the moving rotary clamp assembly is arranged on the fixing frame in a manner of moving up and down; the rotating clamp power assembly is in transmission connection with the fixed rotating clamp assembly and the moving rotating clamp assembly and used for driving the fixed rotating clamp assembly and the moving rotating clamp assembly to conduct screwing-on and screwing-off operation. The rotating clamp separating and combining mechanism is used for driving the fixed rotating clamp assembly and the moving rotating clamp assembly to be horizontally separated. The power mechanism is in transmission connection with the moving rotary clamp assembly and used for driving the moving rotary clamp assembly to move up and down. According to the technical scheme provided by the utility model, the structure can be simplified, the cost is reduced, and the reliability and applicability are improved.

The utility model discloses a lossless torque dismounting tool of a lower shaft sleeve for an oil sprayer, which belongs to the technical field of mechanical maintenance tools and comprises a torque controller, a locking piece and two symmetrical arc-shaped hoops, the locking piece is fixed on the two arc-shaped hoops, and the position of the locking piece can be adjusted. The two arc-shaped hoops are fixed through the locking piece to form a hoop sleeve used for clamping and holding a lower shaft sleeve of the oil sprayer, after the two arc-shaped hoops are clamped and fixed to the lower shaft sleeve of the oil sprayer, a gap of 1-2 mm is reserved between the side end faces of the two arc-shaped hoops, and a torsion hole matched with a torsion controller is formed between the top ends of the two arc-shaped hoops. The torsion hole and the hoop sleeve are both coaxial with the oil sprayer lower shaft sleeve. The torque controller is stressed to drive the hoop sleeve to rotate through the torque hole and disassemble and assemble the oil injector lower shaft sleeve, so that the problems that the torque application cannot be consistent with the manufacturer standard when the oil injector is autonomously repaired, and the oil injector lower shaft sleeve is easily damaged and scrapped due to the pipe wrench side rotation torque are solved; the device has the advantages of being high in autonomous repairing and dismounting efficiency, standardized in dismounting torque and low in maintenance cost.

1. Name of the product in this design: Pipe wrench (25-01). 2. Purpose of this design: A manual tool for rotating steel pipe workpieces. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: a 3D model.

The invention relates to the technical field of manual hardware tools, in particular to a method for rapidly adjusting the opening amount of a multifunctional large-opening wrench. Comprising a wrench body and a wrench opening, a gear shifting tooth position is arranged in the middle of the wrench body, a gear shifting pin penetrates through a pin hole, the gear shifting tooth position enables the wrench body and the wrench opening to be assembled and connected, a smooth face and a gear shifting tooth shape matched with the gear shifting tooth position are arranged on the side face of the gear shifting pin, a button is arranged at one end of the gear shifting pin, and the other end of the gear shifting pin makes contact with a reed fixed to the wrench opening. An arc groove and a positioning hole are formed in the positions, clamping a workpiece, of the head of the wrench body and the head of the wrench opening respectively, a quick-change head is assembled in the arc groove, and the quick-change head is connected with the wrench body and the wrench opening through an elastic pin structure installed in the positioning hole. When the gear shifting pin is pressed to enable the gear tooth form to be separated from the gear shifting tooth position, the wrench opening can quickly slide along the gear shifting tooth position, the opening can be quickly adjusted, and the working efficiency is improved; the wrench is diversified in function, bolts or nuts can be screwed, and the wrench can be used as a pipe wrench or a bathroom wrench by quickly replacing different quick-change heads according to requirements.

The present application relates to the technical field of oil field, in particular to a pipe wrench device, including support, setting on the support integrated wrench and drive assembly; the drive assembly can drive integrated wrench move in horizontal direction; the integrated wrench includes pipe wrench body, the pipe wrench body includes up and down floating connection main wrench and back wrench; the main wrench and back wrench are provided with the jaw; the main wrench includes fixed part and the rotating part in the fixed part, a pair of jaw plates are arranged on the rotating part, the jaw plate is located at the jaw, the jaw plate is detachably connected with the clamp block; the back wrench includes fixed part and the rotating part in the fixed part, a pair of tooth block clamp blocks are arranged on the rotating part, the tooth block clamp block is located at the jaw, and the tooth block clamp block is detachably connected with the tooth block.The integrated wrench is set on the support, and the integrated wrench is driven to move forward and backward by the drive assembly, so as to facilitate the make-up and breakout operation; the integrated wrench can replace the clamp block and tooth block, and can be suitable for pumping pipe and pumping rod.

1. The name of the design product: handle (movable wrench). 2. The use of the design product: anti-skid insulation for pipe wrench handle, wrench handle. 3. The design points of the design product: the combination of shape and pattern. 4. The picture or photo that best indicates the design points: perspective view.

1. The name of the design product: pipe wrench. 2. The use of the design product: for fastening or disassembling pipe fittings. 3. The design points of the design product: in shape. 4. The picture or photo that best shows the design points: perspective view.

The utility model relates to a wheel disc type shallow layer spiral drill centralizing device which comprises a wheel disc, a drill rod connector, a spiral drill, a centralizing frame and a pipe screwing wrench, the wheel disc is connected with the spiral drill through the drill rod connector, the spiral drill penetrates through the centralizing frame so as to centralize the spiral drill in the drilling process, and the pipe screwing wrench is hinged to a bottom plate of the centralizing frame so as to disassemble and assemble the spiral drill. According to the righting device for the wheel disc type shallow layer spiral drill, automatic righting in the drilling process of the spiral drill is achieved through the arrangement of the two righting openings in the righting frame, the spiral drill is rapidly disassembled through the fact that the pipe screwing wrench is hinged to the bottom plate of the righting frame, and the righting device is simple in structure, convenient to manufacture, high in efficiency, safe, reliable and suitable for popularization and application. And the labor cost in the exploration process of the shallow spiral drill is saved.

1. Name of the product in this design: Pipe wrench (FA). 2. Purpose of this design: for the installation and disassembly of tubular components, etc. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: 3D view 1.

The utility model provides a pipe wrench suitable for an internal thread pipe, which belongs to the field of tools and comprises a rod body, a chain and two connecting pieces. An adjusting section is arranged at one end of the rod body; the two connecting pieces are detachably installed on the adjusting section, can move on the adjusting section in the length direction of the rod body and are distributed side by side at intervals. The two ends of the chain correspond to the outer surfaces of the two connecting pieces in a one-to-one mode and are rotationally connected. The chain, the two connecting pieces and the adjusting section located between the two connecting pieces jointly define a clamping ring used for being provided with an inner threaded pipe in a matched mode. The connecting rod has the advantages that the clamping ring is used for being arranged on the periphery of the inner threaded pipe in a sleeved mode, the chain is used for clamping the inner threaded pipe, the inner threaded pipe is arranged in the clamping ring, when the chain clamps the inner threaded pipe, the inner threaded pipe can be rotated by rotating the other end of the rod body, and disassembly and assembly between the inner threaded pipe and all pipeline assemblies are completed; stress points are more, so that the internal threaded pipe is not easy to be damaged by clamping.

The invention relates to the technical field of hardware tools, in particular to a portable light pipe wrench which comprises a wrench handle, and adjusting teeth are arranged on the portion, close to the front end, of the outer side of the wrench handle; the upper plier body is rotationally mounted at the front end of the plier handle through a pin shaft, and an upper jaw assembly is arranged in the upper plier body; the rectangular sliding seat sleeves the periphery of the forceps handle, an adjusting ring matched with the adjusting teeth is arranged in the rectangular sliding seat, and one end of the rectangular sliding seat is fixedly connected with a supporting seat; the lower jaw is detachably and fixedly mounted at the top end of the supporting seat; through the screw connection of the upper jaw and the triangular prism and the magnetic type detachable structure of the lower jaw and the supporting seat, the independent replacement and flexible switching of the upper jaw and the lower jaw are realized. When the jaw is abraded, the whole pipe wrench does not need to be replaced, and only a single jaw needs to be replaced, so that the use cost is reduced; and meanwhile, different types of jaws with thin tooth surfaces, middle tooth surfaces, thick tooth surfaces and the like can be selected according to the material and the surface state of the pipe fitting, so that the pipe fitting is prevented from being damaged, and the clamping stability is improved.

The utility model relates to the technical field of tools, and discloses an adjustable pipe wrench convenient to disassemble, which comprises a wrench seat, a movable toothed plate pin shaft and a fixed seat are respectively arranged at the upper end and the lower end in the wrench seat, and a pipe wrench nut is rotatably connected in the upper end of the wrench seat. A fixed jaw and a movable jaw are fixedly installed at the left end of the fixed seat and the left end of the movable toothed plate pin shaft respectively, and through the collaborative design of the clamp seat, the fixed seat, the movable toothed plate pin shaft, the pipe clamp nut, the first positioning plug pin and the second positioning plug pin, the movable toothed plate pin shaft can flexibly move in the clamp seat by rotating the pipe clamp nut. After the fixed seat is inserted into the clamp seat, a locking bolt penetrates through a locking hole for fastening, a first positioning bolt and a second positioning bolt are respectively fixed at the upper end and the lower end of the fixed seat by using bolts, and the other end of the bolt is inserted into a positioning slot, so that the design is convenient to disassemble, and is convenient to use. The problem that an integral pipe wrench is difficult to disassemble and clean is solved.

1. Name of the product in this design: Pipeline wrench (pointed 25-02). 2. Purpose of this product design: Pliers for clamping and adjusting wires and tubing. 3. The key design feature of this product is its shape. 4. The image or photograph that best illustrates the design's key points: a 3D model.

The utility model relates to the technical field of pipe tongs, in particular to a knockable fast-adjusting pipe tong which comprises a main tong frame, the main tong frame comprises a top clamping arm and a connecting arm rod, the top clamping arm is installed on the head of the connecting arm rod, the top clamping arm and the connecting arm rod are integrally formed, a movable frame is installed on the connecting arm rod in a sleeved mode, and the movable frame is connected with the main tong frame. An adjusting wheel in threaded fit with the connecting arm rod is rotationally installed in the movable frame, and a bottom clamping arm corresponding to the top clamping arm is fixedly installed on the upper end face of the movable frame. The movable frame is mounted on the main clamp frame, and the bottom clamping arm is fixedly mounted on the movable frame, so that the distance between the top clamping arm and the bottom clamping arm can be adjusted by rotating the adjusting wheel during use, and a pipeline can be better clamped and used conveniently; in this way, during use, knocking can be directly conducted through the knocking assembly.