Net hauler for trawler

The present disclosure belongs to the technical field of fishing operation equipment in fishery, and relates to a net hauler for a trawler. The net hauler includes two rope drums, a drum rotation shaft is disposed on each rope drum and includes a first rotation shaft and a second rotation shaft, a drum is disposed on the first rotation shaft, a cylindrical housing is disposed between two ends of the first rotation shaft and the second rotation shaft, a pivot is disposed on the cylindrical housing. The present disclosure has advantages of changing a net hauling speed and improving a fishing efficiency.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to Chinese Patent Application No. 201911243041.2 with a filing date of Dec. 6, 2019. The content of the aforementioned application, including any intervening amendments thereto, are incorporated herein by reference.

TECHNICAL FIELD

The present disclosure belongs to the technical field of fishing operation equipment in fishery, and particularly relates to a net hauler for a trawler.

BACKGROUND

A net hauling process of a trawler may be divided into three stages. At the first stage, nets are straightened out sequentially and placed at a rear end of a net hauler. At the second stage, the nets are placed slowly into sea and opened sequentially behind the stern of the trawler to perform a dragging operation. At the third stage, the nets are gradually hauled back onto a stern deck of the trawler by a hydraulic motor supplying power. The existing trawler supplies a driving force by only one hydraulic motor with low output power and the hydraulic motor within a given rotation speed range is difficult to regulate in speed, affecting the net hauling efficiency and bringing much inconvenience to users.

SUMMARY

To solve the above problems in the prior art, the present disclosure provides a net hauler for a trawler. Technical problems to be solved by the present disclosure are: how to change a net hauling speed and improve a fishing efficiency.

The present disclosure may be achieved by the following technical solution. A net hauler for a trawler includes two rope drums disposed at left and right sides. A drum rotation shaft is axially disposed on each of the rope drums and includes a first rotation shaft and a second rotation shaft which are coaxially disposed, a drum is coaxially fixed on the first rotation shaft, a cylindrical housing is coaxially fixed between two opposing ends of the first rotation shaft and the second rotation shaft, a pivot is axially and rotatably disposed on the cylindrical housing, and a driving mechanism capable of driving the pivot to rotate is disposed in the cylindrical housing; at least one circular plate is coaxially fixed on the pivot, a plurality of sliding grooves are uniformly opened on a side surface of the circular plate around the pivot, an inner wall at one end of each sliding groove penetrates through an edge of the circular plate, and the other end of the sliding groove extends toward a middle part of the circular plate; a sliding arm is slidably disposed on each sliding groove, a plurality of positioning holes corresponding to the sliding arms are opened on the cylindrical housing, and the other end of the sliding arm protrudes out of the corresponding positioning hole and is fixedly provided with an arc plate; and a rope with a free end connected with a trawling net is wound on the drum.

In the above net hauler for a trawler, a controller is further included; a first water flow ejector with a water spray mouth facing backward is disposed at a tail of the trawling net, and the first water flow ejector is electrically connected with the controller through a power supply.

In the above net hauler for a trawler, an air bag is disposed around the tail of the trawling net, an air compression cylinder is disposed on the air bag, and a discharge end of the air compression cylinder is in communication with the air bag and has a solenoid valve which is in electrical connection with the controller through the power supply.

In the above net hauler for a trawler, a shifter lever is fixed at an edge of each arc plate close to the drum.

In the above net hauler for a trawler, a vertically-downward lower baffle plate is fixed at left and right edges of each arc plate respectively.

In the above net hauler for a trawler, the driving mechanism includes a worm wheel coaxially fixed on the pivot, a motor is fixed at an inner wall of the cylindrical housing, and an output shaft of the motor is transmission-connected with a worm screw engaged with the worm wheel.

In the above net hauler for a trawler, a circular pipe uniformly provided with several second water flow ejectors is disposed around the trawling net, and a water ejection mouth of the second water flow ejector is disposed toward the tail of the trawling net; the second water flow ejector is electrically connected with the controller through the power supply.

In the above net hauler for a trawler, the circular pipe has a hollow cavity, and the circular pipe is made of high-density polystyrene.

In the above net hauler for a trawler, a hair brush is disposed on an inner side surface of the circular pipe through a hair brush holder, and the tip of the hair brush extends into the trawling net.

In the above net hauler for a trawler, a connection rope is connected between a front end of the trawling net and the circular pipe.

Compared with the prior art, the net hauler of the present disclosure has the following advantages.

1. When the trawling net is lowered into seawater for fishing, the rope on the arc plate is completely separated and connected with the front end of the trawling net through the rope on the drum. After the trawling net completes fishing, the driving mechanism is started according to a desired net hauling speed to drive the circular plate to rotate through the pivot. At this time, the sliding groove on the circular plate moves to enable each sliding arm to extend out of and into the corresponding positioning hole under the action of the sliding groove. At the same time, the sliding arm drives the arc plate to increase and decrease a distance between the arc plate and an axis of the pivot. In this case, the arc plate changes its linear speed under the same rotation speed so as to adjust the speed of taking back the rope. In the process of taking back the trawling net, the hydraulic motor drives the drum rotation shaft through a driving gear, and the drum rotation shaft drives the drum and six arc plates to rotate synchronously. With the increase of the rope wound on the drum, the rope already wound on the drum squeezes the rope to be wound on the rope drum onto the arc plate. In addition, a gap is formed between two adjacent arc plates. After the rope is wound on the arc plate, the edge of the arc plate and the rope are squeezed each other to increase a frictional force between the rope and the arc plate, so that the rope already wound on six arc plates is uneasy to slip. At the same time, since the above frictional force is greater than the frictional force of the rope on the drum, the rope is separated more easily from the drum and then wound on six arc plates. Hence, the rope on the drum is returned gradually to the arc plate so that the arc plate takes back the trawling net through the rope, thereby adjusting the net hauling speed. In the above process, the distance from each arc plate to the axis of the pivot is changed to enable the arc plate to have a different linear speed under the same rotation speed of the drum rotation shaft, thereby increasing or decreasing the speed of winding the rope on the rope drum, changing the net hauling speed, and effectively improving the fishing efficiency.

2. Upon start, the first water flow ejector sucks external seawater and ejects the seawater backward, so that the tail of the trawling net is subjected to a forward reactive force generated by the seawater and thus pushed to move forward. The structure further improves the efficiency of taking back the trawling net, increasing the net hauling speed, and also reducing a pulling force received by the rope at the same time.

3. The air compression cylinder inflates the air bag to expand it. A buoyancy force generated by the air bag brings the tail of the trawling net to float upward, so that the tail of the trawling net is gradually flush with the front end of the trawling net, reducing the contact area of the trawling net and water, diminishing the resistance of water against the moving trawling net, and facilitating improving the speed of taking back the trawling net.

4. Upon start, the second water flow ejector sucks the external seawater and ejects water flow toward the tail of the trawling net, and the ejected water flow washes aquatic products attached to the trawling net to enable them to flow toward the middle part of the trawling net; at the same time, since the reactive force generated by the seawater acts on the circular pipe to push the circular pipe to move forward, an inner side surface of the circular pipe contacts and squeezes the trawling net to move forward while gradually drawing in the trawling net to reduce a transverse area of the trawling net, thereby reducing the resistance of water against the trawling net. In addition to removing the aquatic products attached to the trawling net, the structure also can facilitate increasing the net hauling speed, thereby improving the fishing efficiency of the net hauler.

5. The disposal of the hair brush facilitates further removing the aquatic products attached to the trawling net, and the combination of the hair brush and the second water flow ejector significantly improves the efficiency of removing the aquatic products attached to the trawling net.

DETAILED DESCRIPTION OF THE EMBODIMENTS

The following descriptions are specific examples of the present disclosure, and the technical solutions of the present disclosure will be further described in combination with accompanying drawings. However, the present disclosure is not limited to these examples.

As shown inFIGS. 1-5, a net hauler for a trawler includes two rope drums1disposed at left and right sides of a hull stern16respectively. The rope drum1has a frame11fixed on the hull stern16, and is mounted on the frame11; a drum rotation shaft12is axially disposed on each rope drum1and includes a first rotation shaft121and a second rotation shaft122which are coaxially disposed, and a drum13is coaxially fixed on the first rotation shaft121; a driving gear123is coaxially fixed on the second rotation shaft122, and transmission-connected with an output shaft of a hydraulic motor disposed on the hull stern16; a cylindrical housing2is coaxially fixed between two opposing ends of the first rotation shaft121and the second rotation shaft122, a pivot21is axially and rotatably disposed on the cylindrical housing2, and a driving mechanism capable of driving the pivot21to rotate is disposed in the cylindrical housing2; two circular plates23are coaxially fixed on the pivot21, and six sliding grooves231are uniformly opened on a side surface of each circular plate23around the pivot21, an inner wall at one end of each sliding groove231penetrates through an edge of the circular plate23, and the other end of the sliding groove231extends toward a middle part of the circular plate23; a sliding arm24is slidably disposed on each sliding groove231, six positioning holes27corresponding to the sliding arms24are opened on the cylindrical housing2, and the other end of the sliding arm24protrudes out of the corresponding positioning hole27to be fixedly provided with an arc plate25; a rope14is wound on the drum13, and a free end of the rope14is connected with a trawling net4through a pulley frame3disposed on the hull stern16; two outer baffle plates15are coaxially fixed on the drum rotation shaft12, and are located at both sides of the drum13and the arc plate25respectively.

In the process of lowering the trawling net4into seawater for fishing, the rope14is completely separated from the arc plate25and connected with the front end of the trawling net4through the rope on the drum13. After the trawling net4completes fishing, the driving mechanism is started according to a desired net hauling speed to drive a circular plate23to rotate through the pivot21. At this time, the sliding groove231on the circular plate23moves to enable each sliding arm24to extend out of and into the corresponding positioning hole27under the action of the sliding groove231. At the same time, the sliding arm24drives the arc plate25to increase and decrease a distance between the arc plate25and an axis of the pivot21. In this case, the arc plate25changes its linear speed under the same rotation speed so as to adjust the speed of taking back the rope. In the process of taking back the trawling net4, the hydraulic motor drives the drum rotation shaft12through the driving gear123, so that the drum rotation shaft12drives the drum13and six arc plates25to rotate synchronously. With the increase of the rope14wound on the drum13, the rope14already wound on the drum13squeezes the rope14to be wound on the rope drum onto the arc plate25. In addition, a gap252is formed between two adjacent arc plates25. After the rope14is wound on the arc plate25, the edge of the arc plate25and the rope14are squeezed each other to increase a frictional force between the rope14and the arc plate25, so that the rope14already wound on six arc plates25is uneasy to slip. At the same time, since the above frictional force is greater than the frictional force of the rope14on the drum13, the rope14on the drum13is more easily separated from the drum13and wound on six arc plates25. The rope on the drum13is gradually returned to the arc plate25so that the arc plate25takes back the trawling net4through the rope14, thereby adjusting the net hauling speed.

In the above process, the distance from each arc plate25to the axis of the pivot21is changed to enable the arc plate25to have a different linear speed under the same rotation speed of the drum rotation shaft12, thereby increasing or decreasing the speed of winding the rope14on the rope drum1, further changing the net hauling speed, and effectively improving the fishing efficiency.

Specifically, the net hauler of the present disclosure further includes a controller7disposed on the hull stern16; a first water flow ejector5with a water spray mouth facing backward is disposed at a tail of the trawling net4, and the first water flow ejector5is electrically connected with the controller7through a power supply; the power supply may be electric energy generated by a power generator on the hull stern16.

In the process of taking back the trawling net4, the controller7sends an electrical signal to the first water flow ejector5to control on and off of the first water flow ejector5. When the first water flow ejector5is turned on, the first water flow ejector5sucks external seawater and ejects the seawater backward, so that the tail of the trawling net4is subjected to a forward reactive force generated by the seawater and thus pushed to move forward.

The structure further improves the efficiency of taking back the trawling net4, increasing the net hauling speed, and also reducing a pulling force received by the rope14at the same time.

Specifically, an air bag6is disposed around the tail of the trawling net4, an air compression cylinder61is disposed on the air bag6, a discharge end of the air compression cylinder61is in communication with the air bag6and has a solenoid valve62which is in electrical connection with the controller7through the power supply.

In the process of taking back the trawling net4, the controller7sends an electrical signal to the solenoid valve62to control opening and closing of the solenoid valve62. When the solenoid valve62is opened, the air compression cylinder61inflates the air bag6to expand it. A buoyancy force generated by the air bag6drives the tail of the trawling net4to float upward, so that the tail of the trawling net4is gradually flush with the front end of the trawling net4, reducing the contact area of the trawling net4and water, diminishing the resistance of water against the trawling net4, and facilitating improving the speed of taking back the trawling net4.

Specifically, a shifter lever28is fixed at an edge of each arc plate25close to the drum13.

The disposal of the shifter lever28facilitates shifting the rope14from the drum13back to six arc plates25when the rope drum1takes back the rope14; in addition, the shifter lever28may further prevent the rope14from accidentally slipping onto the drum13accidentally.

Specifically, a vertically-downward lower baffle plate251is fixed at left and right edges of each arc plate25respectively.

The disposal of the lower baffle plate251prevents the rope14from slipping into a space below the arc plate25.

Specifically, the driving mechanism includes a worm wheel22coaxially fixed on the pivot21, a motor29is fixed on an inner wall of the cylindrical housing2, an output shaft of the motor29is transmission-connected with a worm screw26, both ends of the worm screw26are disposed in the cylindrical housing2through a mounting seat261respectively, and the worm screw26is engaged with the worm wheel22; the motor29is a stepping motor.

When the driving mechanism is started, the output shaft of the motor29drives the worm screw26to rotate, the worm screw26then drives the pivot21through the worm wheel22, and the pivot21then drives the circular plate23to rotate. In this way, the sliding arm24may extend out of and into the positioning hole27.

Specifically, a circular pipe8uniformly provided with two second water flow ejectors81is disposed around the trawling net4, and a water spray mouth of the second water flow ejector81faces toward the tail of the trawling net4; the second water flow ejector81is electrically connected with the controller7through the power supply.

In the process of taking back the trawling net4, the controller7sends an electrical signal to the second water flow ejector81to control on and off of the second water flow ejector81. After being started, the second water flow ejector81sucks external seawater and ejects water flow toward the tail of the trawling net4, and the ejected water flow washes aquatic products attached to the trawling net4to enable the aquatic products to flow toward the middle part of the trawling net4; at the same time, since the reactive force generated by the seawater acts on the circular pipe8to push the circular pipe8to move forward, an inner side surface of the circular pipe8contacts and squeezes the trawling net4to move forward while gradually drawing in the trawling net4to reduce a transverse area of the trawling net4, thereby reducing the resistance of water against the trawling net4.

In addition to removing the aquatic products attached to the trawling net4, the structure also facilitates increasing the net hauling speed, thereby improving the fishing efficiency of the net hauler of the present disclosure.

Specifically, the circular pipe8has a hollow cavity84, and the circular pipe8is made of high-density polystyrene.

The structure facilitates increasing the buoyancy force of the circular pipe8. The buoyancy force generated by the circular pipe8facilitates driving the trawling net4to float upward, thereby reducing the contact area of the trawling net4and the seawater, and further reducing the resistance of water against the trawling net4.

Specifically, a hair brush82is disposed on an inner side surface of the circular pipe8through an annular hair brush holder821, and a tip of the hair brush82extends into the trawling net4.

The disposal of the hair brush82facilitates further removing the aquatic products attached to the trawling net4, and the combination of the hair brush82and the second water flow ejector81significantly improves the efficiency of removing the aquatic products attached to the trawling net4.

Specifically, a connection rope83is connected between the front end of the trawling net4and the circular pipe8.

The disposal of the connection rope83facilitates the connection between the circular pipe8and the trawling net4.

The specific examples described herein are merely illustrative of the spirit of the present disclosure. Persons skilled in the art may make various modifications or supplementations or substitutions in a similar manner to the described specific examples without departing from the spirit of the present disclosure or surpassing the scope defined in the appended claims.