JP3740924B2 - Reverse gear for water jet propulsion boats - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of a propulsion device in a water jet propulsion boat, and more particularly to a reverse device that performs forward / reverse switching.
[0002]
[Prior art]
Conventionally, as a reverse device in this type of water jet propulsion boat, there are those described in JP-A-58-170695 and JP-A-8-276895.
[0003]
In the invention of Japanese Patent Laid-Open No. 58-170695, an opening is formed on the bottom surface of a nozzle tube, and an inner flap and an outer flap that can be opened and closed are provided above and below the opening. That is, a drive cylinder is attached to one end of two control levers provided on the left and right side walls of the nozzle tube, and an inner flap is integrally attached to the other end. The inner flap is opened and closed by expansion and contraction of the drive cylinder. A device is disclosed in which a flap is pivotally attached, and the inner flap is opened and closed to open and close the outer flap with a link mechanism having a pivot fulcrum on the nozzle tube, thereby switching the boat forward and backward. .
[0004]
In the invention of Japanese Patent Laid-Open No. 8-276895, a hydraulic cylinder is disposed above the upper wall of the steering cylinder, an operating shaft with a flap is provided below the upper wall of the steering cylinder, and is opened at the center of the upper wall of the steering cylinder. A window is provided, the lever protrudes upward from the opening window, the upper end of the lever is connected to the hydraulic cylinder, the lower end is connected to the operating shaft, and an interlocking link for operating the flap and the bucket is interlocked. And a device for switching a boat between forward and reverse by expanding and contracting a hydraulic cylinder is disclosed.
[0005]
[Problems to be solved by the invention]
The above-described conventional boat reverse apparatus has the following problems. That is, in the invention described in Japanese Patent Application Laid-Open No. 58-170695, the inner flap is formed integrally with the operation lever, and its rotation fulcrum is provided at a substantially middle portion of the operation lever. Since a large force is applied to the inner flap and the operation lever, a considerable strength is required and the weight is increased. In addition, when switching from the reverse state to the forward state, all the water pressure from the pump is acting on the inner flap, so a large force is required to close the opening with the inner flap in a horizontal state against this water pressure. This increases the burden on the drive cylinder.
[0006]
In the invention described in JP-A-8-276895, there is an opening window at the upper part of the steering cylinder, and in order to prevent the jet flow from the ejection nozzle from being ejected from the opening window at the time of reverse travel, the shielding plate is attached to the operating shaft. Provided. However, since the shielding plate is fixed to the operating shaft, the angle is such that the shielding plate guides the jet from the opening window to the outside when the flap is in the horizontal state. For this reason, when the boat moves forward, particularly at low speed, the speed of the jet flow from the jet nozzle becomes slow, and the seawater jetted from the jet nozzle with the reduced opening is opened and immediately starts to diffuse. The diffused seawater is ejected from the opening window through the shielding plate. At this time, some seawater ejected from the opening window rises along the lever and scatters to a driving device such as a hydraulic cylinder, which may cause corrosion of these driving devices. Further, the upper flap is provided below the upper wall of the steering cylinder, and it is necessary to enlarge the steering cylinder by the storage space for the flap and the operating shaft, which increases the weight accordingly. In addition, since a large torque is applied to the shaft connecting the upper flap and the lever, there is a problem that considerable strength is required and the weight is increased.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the reverse device of the water jet propulsion boat according to the present invention sucks water into the pump casing from a suction port opened at the bottom of the water jet propulsion boat, pressurizes the water with the water jet propulsion device, In addition to injecting pressurized water from the discharge casing provided at the stern, a square-shaped deflector that can be rotated to the left and right is provided at the rear end of the discharge outlet of the discharge casing, and the rear opening of the deflector is closed to change the traveling direction from forward to backward. In the water jet propulsion boat provided with the reverser to be switched to the above, the above reverser is formed by the upper reverser and the lower reverser, the upper reverser constitutes the upper wall surface of the deflector, and the lower reverser constitutes the lower wall surface of the deflector. The lower reverser is pivotally attached to one end of a dogleg-shaped lever having a support pin provided at the bent portion on the side surface of the deflector, and the other end of the lever is connected to a drive cylinder. The lower reverser is connected to the upper reverser via a link. By extending the drive cylinder, the upper reverser and the lower reverser are respectively rotated by a lever and a link mechanism to form a substantially arc-shaped reverse flow path. The bottom of the deflector is opened and is configured to serve as a jet for the backward jet.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
According to the present invention configured as described above, when the boat is moved backward, the drive cylinder is extended, so that the lever with the support pin as a fulcrum is rotated. A lower end portion of the lever and a rear end portion of the lower reverser are connected, and an intermediate portion of the lower reverser and a front end portion of the deflector bottom portion are connected by a small link. Further, the lower end portion of the large link was connected to the small link connecting pin of the lower reverser, and the upper end portion of this link was connected to the middle portion of the upper reverser. Since the front end portion of the upper reverser is pivotally supported by the upper portion of the deflector, the rear end portion of the upper and lower reversers is rotated inward of the deflector by rotating the lever, and the rear end portions are brought into close contact with each other. Further, the backward end of the lower reverser is rotated downward to form a backward flow injection port. As described above, the reverse flow path having a substantially arc-shaped curve is formed by the upper reverser and the lower reverser. Thus, since the top wall and the bottom wall of the deflector are configured as the upper and lower reversers, the shape of the deflector can be reduced and the weight can be reduced.
[0009]
【Example】
Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 is a side view in which a part of a water jet propulsion boat 1 to which a reverse device of the present invention is applied is cut. Water is sucked into a pump casing 6 from a suction port 5 opened in a ship bottom 2 and driven by an engine 15. The water jet is pressurized by an impeller (not shown) of the water jet propulsion device 4 and the pressurized water is injected from the rear opening of the deflector 7 provided at the rear end of the discharge casing 8 attached to the stern 3. is there.
[0010]
Next, the reverse gear device of the present invention will be described in detail with reference to FIGS. FIG. 2 is a side view of the water jet propulsion device 4, and water pressurized by the water jet propulsion device 4 is jetted from the jet outlet 9 at the rear end portion of the discharge casing 8 to the deflector 7. The deflector 7 is supported by a pin 16 so as to be able to turn left and right, and can be turned left and right by a driving device (not shown) to change the course of the water jet propulsion boat 1 to the left and right. When the traveling direction of the water jet propulsion boat 1 is switched from forward to reverse, a reverse passage is formed using a reverse device composed of a reverser 10, a lever 11, a drive cylinder 12, and the like. The operation of this reverse gear will be described below with reference to FIGS.
[0011]
FIG. 3 is a side sectional view of the deflector 7 in a state where the water jet propulsion boat 1 is traveling forward. The drive cylinder 12 is disposed on the upper portion of the deflector 7, and the piston rod end 12a of the drive cylinder 12 is connected to the upper end portion of the lever 11 having a square shape with a pin 12b. The drive cylinder 12 may be disposed at one location at the upper center of the deflector 7 in the reverse device of the small boat, and the drive cylinder 12 is disposed at two locations on the left and right of the upper portion of the deflector 7 in the reverse device of the relatively large boat. In the case of one drive cylinder 12, the left and right levers 11 are connected by a single pin 12b, and the piston rod end 12a is attached to the center of the pin 12b.
[0012]
The lever 11 is a bent portion of a square shape and is rotatable about the support pin 11a as a fulcrum. The lower end of the lever 11 and the rear end of the lower reverser 10b are connected by a pin 10c. And the lower end part of the link 13a and the rear end part of the link 13b are connected to the middle part of the lower reverser 10b slightly closer to the front end by a pin 10d. The front end portion of the link 13b is connected to the bottom front end portion of the deflector 7 by a pin 7a. Further, the upper end portion of the link 13a is connected to a pin 10e fixed to an intermediate portion of the upper reverser 10a. And the front-end part of the upper reverser 10a is pivotally supported by the upper part of the deflector 7 with the axis | shaft 10f. In the state of FIG. 3 in which the rear half of the top wall of the deflector 7 is constituted by the upper reverser 10a and the latter half of the bottom wall is constituted by the lower reverser 10b, the upper reverser 10a and the lower reverser 10b are the top and bottom walls of the deflector 7. The jet flow from the jet port 9 is smoothly guided to the rear opening of the deflector 7.
[0013]
Next, the operation from forward traveling to the neutral (stopped) state will be described with reference to FIG. By extending the drive cylinder 12, the upper end portion of the lever 11 is rotated backward, and the lower end portion of the lever 11 is rotated forward. Then, the pin 10 c moves toward the inside of the deflector 7 along a substantially mountain-shaped notch 7 b provided in the lower part of the deflector 7. In other words, the rear end portion of the lower reverser 10b also moves in the inner direction of the deflector 7 together with the pin 10c. Then, the front end portion of the lower reverser 10 b is rotated downward by the link 13 b to form the injection port 14. Further, the upper reverser 10a is rotated inward of the deflector 7 about the shaft 10f by the link 13a. At this time, the pin 10e moves along an arc-shaped long hole 7c provided on the side of the deflector 7. Then, about half of the jet flow from the jet port 9 is jetted from the rear opening of the deflector 7 as a forward flow from between the rear end of the upper reverser 10a and the rear end of the lower reverser 10b, and the other half is the upper reverser 10a. Then, it is guided to the lower reverser 10b and is injected obliquely forward as a backward flow from the injection port 14. The water jet propulsion boat 1 is stopped when the forward flow and the reverse flow are equalized.
[0014]
Next, the operation from the stop state to the reverse drive state will be described with reference to FIG. By further extending the drive cylinder 12 from the neutral state shown in FIG. 4, the rear end portions of the upper reverser 10a and the lower reverser 10b are brought into close contact with each other inside the deflector 7 to form a substantially arc-shaped reverse flow path. The entire amount of the jet flow from 9 is guided to the reverse flow path and ejected from the injection port 14 as a reverse flow. Then, when switching from the reverse drive state to the forward drive state again, the drive cylinder 12 may be reduced. Reference numeral 17 shown in FIG. 6 denotes a link cover, which is disposed on the left and right side surfaces of the deflector 7. This link cover 17 prevents the leakage of jet water from the arc-shaped long hole 7c provided on the side of the deflector 7, and the situation where the reverser 10 becomes inoperable due to entanglement of floating substances on the water surface in the link mechanism. It is attached for the purpose of preventing or reducing that the lever 11 and the link mechanism become wind wave resistance.
[0015]
【The invention's effect】
Since the reverse device of the present invention is configured as described above, the jet port at the rear of the deflector is closed or opened while the water pressure from the pump is dispersed by the up / down reverser when the ship moves forward and backward. The load of is reduced. Further, since the upper and lower wall surfaces of the deflector are composed of the upper and lower wall surfaces, the deflector shape can be reduced in size and weight. And by shielding the lever and link mechanism projections arranged on the side of the deflector by the link cover provided on the deflector, the resistance of wind waves is reduced, and further, floating substances on the water surface are entangled with the lever and link mechanism, The situation where driving becomes impossible can be avoided.
[Brief description of the drawings]
FIG. 1 is a side view of a part of a water jet propulsion watercraft having a reverse device according to the present invention.
FIG. 2 is a side view of a water jet propulsion device using a reverse gear according to the present invention.
FIG. 3 is a longitudinal sectional view of a deflector in a forward state of a water jet propulsion boat according to the present invention.
FIG. 4 is a longitudinal sectional view of the deflector when the water jet propulsion boat is stopped.
FIG. 5 is a longitudinal sectional view of the deflector in a reverse state of the water jet propulsion boat.
FIG. 6 is a side view of a deflector in the water jet propulsion boat according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Water jet propulsion boat 2 Ship bottom 3 Stern 4 Water jet propulsion apparatus 5 Suction port 6 Pump casing 7 Deflector 7c Long hole 8 Discharge casing 9 Spout 10 Reverser 10a Upper reverser 10b Lower reverser 10d, 10e Pin 11 Lever 11a Support pin 12 Drive Cylinders 13a and 13b Link 14 Injection port 17 Link cover

Claims (2)

Water is sucked into the pump casing (6) from the suction port (5) opened on the bottom (2) of the water jet propulsion boat (1), and water is pressurized by the water jet propulsion device (4), and is provided at the stern (3). In addition to injecting pressurized water from the discharge casing (8), the rear end of the discharge casing (8) of the discharge casing (8) is provided with a quadrilateral deflector (7) that can be rotated left and right. In a water jet propulsion boat (1) provided with a reverser (10) for closing the rear opening and switching the traveling direction from forward to reverse, the reverser (10) is divided into an upper reverser (10a) and a lower reverser (10b). The upper reverser (10a) constitutes the upper wall surface of the deflector (7), and the lower reverser (10b) constitutes the lower wall surface of the deflector (7). A support pin (11a) is provided on the side surface of the kuta (7), and a bent portion of a U-shaped lever (11) is rotatably supported on the support pin (11a). One end of the lever (11) is attached to the support pin (11a). It is pivotally attached to the rear end of the lower reverser (10b), the other end is rotatably connected to the drive cylinder (12), and a pin (10d) provided at the middle or front end of the lower reverser (10b) is injected. The lower end of the front part of the mouth (14) is rotatably connected by a link (13b), and the front end part of the upper reverser (10a) is pivotally supported by the upper part of the deflector (7), and the middle of the upper reverser (10a). The pin (10e) provided in the part is inserted into an arc-shaped elongated hole (7c) drilled in the side part of the deflector (7), and further, the pin (10d) of the lower reverser (10b) and the upper reverser (10a) Connect the pin (10e) with the link (13a) When the drive cylinder (12) is extended by being movably connected, the rear part of the lower reverser (10b) is rotated upward by the link action, and at the same time, the rear part of the upper reverser (10a) is rotated downward. A reverse device for a water jet propulsion boat, characterized by forming an arcuate reverse passage. The reverse device for a water jet propulsion boat according to claim 1, wherein a link cover (17) is provided on a side surface of the deflector (7).

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