Steering machine

Abstract

A steering machine (1A) according to an embodiment includes: a rudder handle (2) fixed to a rudder shaft (11); a ram (3) provided with a pin (31) that engages with the rudder handle (2); and a pair of cylinders (4A, 4B) into which two ends of the ram (3) are inserted. Furthermore, the steering device (1A) includes a bracket (7) that bridges the cylinders (4A, 4B) so as to allow variation in the distance between the cylinders (4A, 4B), and a stroke sensor (8). The stroke sensor (8) includes a detection element (84), and a linear detector (81) that detects the position of the detection element (84) and extends in the axial direction of the ram (3). The detection element (84) is attached to the ram (3) or the bracket (7), and the linear detector (81) is attached to the other of the ram (3) and the bracket (7).

Description

steering gear

[0001] The present disclosure relates to a steering gear installed on a vessel.

[0002] Conventionally, a Rapson slide-type steering gear including a ram and a pair of cylinders has been known. In such steering gears, the steering angle is generally detected by a rotation angle sensor. For example, FIG. 2 of Patent Document 1 describes that the rotation angle sensor is disposed at a position away from the steering gear. Also, FIG. 2 of Patent Document 1 describes that the rudder and the rotation angle sensor are connected via a link mechanism so that the centers of the rudder stock and the rotation angle sensor are located at adjacent vertices of a parallelogram.

[0003] Japanese Patent Application Publication No. 3-99997

[0004] However, when detecting the rudder angle using a rotation angle sensor, the rotation angle sensor cannot be adjusted until the steering gear is installed on the ship. Moreover, the position of the rotation angle sensor must be geometrically adjusted on the ship, which is time-consuming.

[0005] Therefore, an object of the present disclosure is to provide a steering gear that allows adjustment of a sensor for detecting a rudder angle before the steering gear is installed on a vessel.

[0006] From a first aspect, the present disclosure provides a steering gear comprising: a tiller fixed to a rudder stock; a ram provided with a pin that engages with the tiller; a pair of cylinders into which both ends of the ram are inserted; a bracket bridging the pair of cylinders to allow for fluctuations in the distance between the pair of cylinders; and a stroke sensor including a detection element and a linear detector extending in the axial direction of the ram that detects the position of the detection element, wherein the detection element is attached to one of the ram and the bracket, and the linear detector is attached to the other of the ram and the bracket.

[0007] From a second aspect, the present disclosure provides a steering gear comprising: a tiller fixed to a rudder stock; a ram provided with a pin that engages with the tiller; a pair of cylinders into which both ends of the ram are inserted; a guide bar parallel to the ram, the guide bar having both ends inserted into retaining holes provided in the pair of cylinders; a guide attached to the ram and sliding along the guide bar while engaging with the guide bar; and a stroke sensor including a detection element and a linear detector extending in the axial direction of the ram that detects the position of the detection element, wherein the detection element is attached to one of the guide and the guide bar, and the linear detector is attached to the other of the guide and the guide bar.

[0008] From a third aspect, the present disclosure provides a steering gear comprising: a tiller fixed to a rudder stock; a ram provided with a pin that engages with the tiller; a first cylinder and a second cylinder into which both ends of the ram are inserted, respectively; and a stroke sensor including a detection element and a linear detector extending in the axial direction of the ram that detects the position of the detection element, wherein each of the first cylinder and the second cylinder includes a tubular portion and a bottom portion, the detection element is attached to one of the ram and the bottom portion of the first cylinder, and the linear detector is attached to the other of the ram and the bottom portion of the first cylinder.

[0009] According to the present disclosure, a steering gear is provided in which the sensor for detecting the rudder angle can be adjusted even before the steering gear is mounted on a vessel.

[0010] 9 is a plan view of the steering gear according to the first embodiment. FIG. 10 is a front view of the steering gear according to the first embodiment. FIG. 11 is a cross-sectional view taken along line III-III in FIG. 2. FIG. 12 is an enlarged cross-sectional view of the other end of the bracket. FIG. 13 is an enlarged cross-sectional view of the other end of the bracket in a modified example. FIG. 14 is an enlarged cross-sectional view of the other end of the bracket in another modified example. FIG. 15 is a plan view of the steering gear according to the second embodiment. FIG. 16 is a front view of the steering gear according to the second embodiment. FIG. 17 is a plan view of the steering gear according to the third embodiment. FIG. 18 is a cross-sectional view taken along line X-X in FIG. 10. FIG. 19 is a plan view of the steering gear according to the fourth embodiment. FIG. 11 is a plan view of the steering gear according to other embodiments.

[0011] 1 and 2 show a steering gear 1A according to a first embodiment. In this embodiment, the steering gear 1A includes a tiller 2 fixed to a rudder stock 11 and one hydraulic actuator 10 that swings the tiller 2. However, the steering gear 1A may include two hydraulic actuators 10 that are arranged parallel to each other with the rudder stock 11 between them.

[0012] The hydraulic actuator 10 includes a ram 3 and a pair of cylinders, a first cylinder 4A and a second cylinder 4B. Both ends of the ram 3 are inserted into the first cylinder 4A and the second cylinder 4B, respectively. For convenience of explanation, the first cylinder 4A side will be referred to as the left and the second cylinder 4B side as the right, but left and right have no technical meaning, and the first cylinder 4A side may be the right and the second cylinder 4B side may be the left.

[0013] 3, the tiller 2 includes a cylindrical portion 21 into which the rudder stock 11 is inserted, and a pair of arms 22 protruding from the side of the cylindrical portion 21. The arms 22 face each other in the vertical direction with the ram 3 in between, and these arms 22 are formed with engagement grooves 23 recessed from their tips.

[0014] A pin 31 is provided in the center of the ram 3 so as to penetrate the ram 3 in the vertical direction. Rollers 32 are attached to the top and bottom of the pin 31, and the pin 31 engages with the engagement groove 23 of the tiller 2 via the rollers 32.

[0015] 1 and 2, each of the first cylinder 4A and the second cylinder 4B includes a tubular portion 41 that slides against the end of the ram 3, and a bottom portion 42 that faces the end face of the ram 3. Furthermore, a flange 43 is provided on the end of the tubular portion 41 opposite the bottom portion 42, i.e., the end on the pin 31 side.

[0016] In each of the first cylinder 4A and the second cylinder 4B, the space surrounded by the tubular portion 41, the bottom portion 42, and the end surface of the ram 3 is the working chamber. Hydraulic oil is supplied from a hydraulic pump to one of the working chambers of the first cylinder 4A and the second cylinder 4B, and the working oil is discharged from the other.

[0017] Furthermore, the steering gear 1A includes a guide bar 5 parallel to the ram 3, and a guide 6 attached to the ram 3 and sliding along the guide bar 5 while engaging with the guide bar 5. The guide 6 serves to prevent rotation of the ram 3. In this embodiment, the guide bar 5 is disposed on the opposite side of the ram 3 from the rudder stock 11.

[0018] The guide bar 5 has a circular cross section with smaller diameters at both ends. The flanges 43 of the first cylinder 4A and the second cylinder 4B are provided with retaining holes 44 that penetrate the flanges 43 in the axial direction of the ram 3. Both ends of the guide bar 5 are inserted into these retaining holes 44.

[0019] The distance between the first cylinder 4A and the second cylinder 4B varies depending on the pressure in the working chambers of the first cylinder 4A and the second cylinder 4B. Because both ends of the guide bar 5 are simply fitted into the retaining holes 44, when the distance between the first cylinder 4A and the second cylinder 4B varies, at least one of the ends of the guide bar 5 slides against the retaining holes 44.

[0020] 3, the guide 6 has a guide groove that opens in a direction perpendicular to the axial direction of the ram 3 and the axial direction of the pin 31, and the guide bar 5 extends through this guide groove. Sliding plates 62 are attached to the inner surface of the guide groove above and below the guide bar 5, and the guide 6 engages with the guide bar 5 via the sliding plates 62.

[0021] In this embodiment, the steering gear 1A includes a bracket 7 arranged on the opposite side of the guide bar 5 from the ram 3, and two stroke sensors 8 including a linear detector 81 attached to the bracket 7 and a detection element 84 attached to the guide 6. In other words, the detection element 84 is attached to the ram 3 via the guide 6. However, the number of stroke sensors 8 may be one.

[0022] The bracket 7 bridges the flange 43 of the first cylinder 4A and the flange 43 of the second cylinder 4B. More specifically, the bracket 7 includes a pair of horizontal bars 71 aligned vertically and parallel to the ram 3, and a pair of vertical bars 72 joined to both ends of the horizontal bars 71. In other words, the vertical bars 72 form one end and the other end of the bracket 7.

[0023] In this embodiment, each horizontal bar 71 is an angle oriented in an inverted L-shape and includes a top plate and a front plate. A linear detector 81 is attached to the underside of the top plate of each horizontal bar 71, so that the linear detector 81 is hidden from the front side of the steering gear 1A by the front plate of the horizontal bar 71.

[0024] Furthermore, the bracket 7 is configured to allow for variations in the distance between the first cylinder 4A and the second cylinder 4B. In this embodiment, the left vertical bar 72, i.e., the left end of the bracket 7, is fixed to the flange 43 of the first cylinder 4A, and the right vertical bar 72, i.e., the right end of the bracket 7, is connected to the flange 43 of the second cylinder 4B so as to be slidable relative to the flange 43. The vertical bar 72 is also an angle. The left vertical bar 72 may be fixed by bolts or welding.

[0025] The right-side vertical bar 72 includes a vertical plate to which the horizontal bar 71 is joined and a horizontal plate that is in surface contact with the end face of the flange 43. As shown in FIG. 4 , the horizontal plate has a long slot 73 that is long in the axial direction of the ram 3, and the bolt 12 is fixed to the flange 43 through this slot 73. The bolt 12 is secured to the flange 43 by means of, for example, a locking compound or welding. Note that the bolt 12 is not shown in FIGS. 1 and 2 to simplify the drawings.

[0026] A washer 13, through which the bolt 12 passes, abuts against the front surface of the horizontal plate of the right vertical bar 72. A compression coil spring 14 is disposed between the washer 13 and the head of the bolt 12, and the biasing force of the spring 14 presses the vertical bar 72 against the flange 43. Therefore, when the distance between the first cylinder 4A and the second cylinder 4B changes, the vertical bar 72 slides against the flange 43. Note that instead of the bolt 12, a headed rod that is press-fit into a fixing hole provided in the flange 43 may be used.

[0027] 1 and 2 , the linear detector 81 of each stroke sensor 8 extends in the axial direction of the ram 3. The stroke sensor 8 is, for example, a magnetostrictive sensor, and the linear detector 81 detects the position of a detection element 84. The linear detector 81 includes a head 82 and a probe 83 extending from the head 82. In this embodiment, the probe 83 is rail-shaped, and the detection element 84 has a shape that engages with the rail. In the illustrated example, the head 82 is located to the left of the probe 83, but the head 82 may also be located to the right of the probe 83.

[0028] The detection element 84 of each stroke sensor 8 slides along the probe 83 of the linear detector 81. The detection element 84 may or may not be in contact with the linear detector 81. The detection element 84 is attached to the guide 6 via an L-shaped support 61.

[0029] As described above, in the steering gear 1A of this embodiment, the stroke sensor 8 can detect the relative position of the detection element 84 with respect to the linear detector 81 as the stroke of the ram 3, and the stroke of the ram 3 can be converted into a rudder angle. Moreover, since the detection element 84 and linear detector 81 of the stroke sensor 8 are attached to the guide 6 and the bracket 7, the stroke sensor 8, which is a sensor for detecting the rudder angle, can be adjusted before the steering gear 1A is installed on the ship.

[0030] Furthermore, the bracket 7 to which the linear detector 81 of the stroke sensor 8 is attached allows for fluctuations in the distance between the first cylinder 4A and the second cylinder 4B, so the stroke sensor 8 will not be damaged by fluctuations in the distance between the first cylinder 4A and the second cylinder 4B.

[0031] <Modifications> In the above embodiment, the linear detector 81 of the stroke sensor 8 is attached to the bracket 7, and the detection element 84 is attached to the ram 3 via the guide 6. However, the linear detector 81 of the stroke sensor 8 may be attached to the ram 3 via the guide 6, and the detection element 84 may be attached to the bracket 7.

[0032] Furthermore, the structure for connecting the right end of the bracket 7 to the flange 43 of the second cylinder 4B so that it can slide on the flange 43 can be modified as appropriate. For example, as shown in Figure 5, the spring 14 may be omitted and the vertical bar 72 may be pressed against the flange 43 by the axial tension of the bolt 12 alone.

[0033] Alternatively, the structure for connecting the right end of the bracket 7 to the flange 43 of the second cylinder 4B so as to be slidable on the flange 43 may be the structure shown in Fig. 6. In the structure shown in Fig. 6, a rod 76 protruding leftward is provided on the vertical plate of the right-side vertical bar 72, while a support plate 74 is provided on the right end of the horizontal bar 71, and a bushing 75 that slides on the rod 76 is attached to the support plate 74.

[0034] The detection element 84 does not necessarily have to be attached to the ram 3 via the guide 6. For example, the detection element 84 may be attached to the ram 3 via a structure other than the guide 6, or may be attached directly to the ram 3. The same applies when the linear detector 81 is attached to the ram 3.

[0035] 7 and 8 show a steering gear 1B according to a second embodiment. In this embodiment and in a third and fourth embodiment described later, the same components as those in the first embodiment are denoted by the same reference numerals, and redundant explanations will be omitted.

[0036] In this embodiment, the bracket 7 is also configured to allow for variation in the distance between the first cylinder 4A and the second cylinder 4B, but the specific structure differs from that of the first embodiment. In this embodiment, a mounting plate 77 is used instead of the right vertical bar 72, and the mounting plate 77 forms the right end of the bracket 7.

[0037] In this embodiment, the left vertical bar 72, i.e., the left end of the bracket 7, is fixed to the flange 43 of the first cylinder 4A, and the mounting plate 77, i.e., the right end of the bracket 7, is fixed to the flange 43 of the second cylinder 4B.

[0038] More specifically, the mounting plate 77 bends from the end face of the flange 43 of the second cylinder 4B and extends to the front of the lateral bar 71. The front plate of the lateral bar 71 is joined in surface contact with the portion of the mounting plate 77 located in front of the lateral bar 71. A portion of the mounting plate 77 has a V-shaped cross section, and this portion constitutes an absorbing section that is elastically deformable in the axial direction of the ram 3.

[0039] Even with this configuration, the same effects as in the first embodiment can be obtained.

[0040] 9 and 10 show a steering gear 1C according to a third embodiment. In this embodiment, the number of stroke sensors 8 is one. Furthermore, in this embodiment, the length of the bracket 7 is set to be shorter than the distance between the first cylinder 4A and the second cylinder 4B, and the bracket 7 is attached to the guide bar 5. In other words, the linear detector 81 of the stroke sensor 8 is attached to the guide bar 5 via the bracket 7. The detection element 84 of the stroke sensor 8 is attached to the guide 6 via the support 61, as in the first embodiment.

[0041] In this embodiment, the bracket 7 includes one horizontal bar 71, and the orientation of the horizontal bar 71 is at an angle that is 90 degrees different from that of the first embodiment. Specifically, the horizontal bar 71 has a top plate and a back plate, and as in the first embodiment, a linear detector 81 is attached to the underside of the top plate. Both ends of the back plate are fixed to the guide bar 5 via spacers 78.

[0042] In this embodiment, as in the first embodiment, the stroke sensor 8 can detect the relative position of the detection element 84 with respect to the linear detector 81 as the stroke of the ram 3, and the stroke of the ram 3 can be converted into a rudder angle. Moreover, because the detection element 84 and linear detector 81 of the stroke sensor 8 are attached to the guide 6 and the guide bar 5, the stroke sensor 8, which is a sensor for detecting the rudder angle, can be adjusted before the steering gear 1C is installed on the ship.

[0043] Furthermore, since the linear detector 81 of the stroke sensor 8 is attached to the guide bar 5, which is not affected by fluctuations in the distance between the first cylinder 4A and the second cylinder 4B, the stroke sensor 8 will not be damaged by fluctuations in the distance between the first cylinder 4A and the second cylinder 4B.

[0044] Contrary to this embodiment, the linear detector 81 of the stroke sensor 8 may be attached to the guide 6 and the detection element 84 may be attached to the guide bar 5 .

[0045] 11 shows a steering gear 1D according to a fourth embodiment. In this embodiment, the linear detector 81 of the stroke sensor 8 is attached to the bottom 42 of the first cylinder 4A, and the detection element 84 is attached to the ram 3. For this reason, the bracket 7 is not employed in this embodiment.

[0046] In this embodiment, the probe 83 of the linear detector 81 is rod-shaped, and the detection element 84 is ring-shaped and passes through the rod. The ram 3 is provided with a hole 33 that opens to the left end face to avoid interference with the probe 83, and the detection element 84 is disposed in the hole 33 near the left end face of the ram 3.

[0047] In this embodiment, as in the first embodiment, the stroke sensor 8 can detect the relative position of the detection element 84 with respect to the linear detector 81 as the stroke of the ram 3, and the stroke of the ram 3 can be converted into a rudder angle. Moreover, because the detection element 84 and linear detector 81 of the stroke sensor 8 are attached to the ram 3 and the bottom 42 of the first cylinder 4A, the stroke sensor 8, which is a sensor for detecting the rudder angle, can be adjusted before the steering gear 1C is installed on the ship.

[0048] Furthermore, since the linear detector 81 of the stroke sensor 8 is attached to the bottom 42 of the first cylinder 4A, which is not affected by fluctuations in the distance between the first cylinder 4A and the second cylinder 4B, the stroke sensor 8 will not be damaged by fluctuations in the distance between the first cylinder 4A and the second cylinder 4B.

[0049] Conversely to this embodiment, the linear detector 81 of the stroke sensor 8 may be attached to the ram 3, and the detection element 84 may be attached to the bottom 42 of the first cylinder 4A.

[0050] Other Embodiments The present disclosure is not limited to the above-described embodiments, and various modifications are possible without departing from the gist of the present disclosure.

[0051] 12, it is also possible to provide a target 91 on the guide 6 and a displacement sensor 92 capable of measuring the displacement of the target 91 on the flange 43 of the first cylinder 4A or the second cylinder 4B. The displacement sensor 92 is, for example, a laser displacement meter or a wire potentiometer.

[0052] <Summary> In a first aspect, the present disclosure provides a steering gear comprising, from a first aspect, a tiller fixed to a rudder stock, a ram provided with a pin that engages with the tiller, a pair of cylinders into which both ends of the ram are inserted, a bracket bridging the pair of cylinders to allow for fluctuations in the distance between the pair of cylinders, and a stroke sensor including a detection element and a linear detector extending in the axial direction of the ram that detects the position of the detection element, wherein the detection element is attached to one of the ram and the bracket, and the linear detector is attached to the other of the ram and the bracket.

[0053] According to the above configuration, the stroke sensor can detect the relative position of the detection element with respect to the linear detector as the ram stroke, and the ram stroke can be converted into a rudder angle. Moreover, because the detection element and linear detector of the stroke sensor are attached to the ram and the bracket, the stroke sensor, which is a sensor for detecting the rudder angle, can be adjusted before the steering gear is installed on the ship.

[0054] As a second aspect, in the first aspect, for example, the above-mentioned steering gear further includes a guide bar parallel to the ram, the guide bar having both ends inserted into retaining holes provided in the pair of cylinders, and a guide attached to the ram and sliding along the guide bar while engaging with the guide bar, and the detection element or the linear detector may be attached to the ram via the guide.

[0055] As a third aspect, in the first or second aspect, for example, the pair of cylinders may be a first cylinder and a second cylinder, and one end of the bracket may be fixed to the first cylinder, and the other end of the bracket may be connected to the second cylinder so as to be slidable relative to the second cylinder.

[0056] As a fourth aspect, in the first or second aspect, for example, both ends of the bracket may be fixed to the pair of cylinders, and the bracket may have an absorbing portion that is elastically deformable in the axial direction of the ram.

[0057] In a fifth aspect, the present disclosure provides, from a second side, a steering gear comprising: a tiller fixed to a rudder stock; a ram provided with a pin that engages with the tiller; a pair of cylinders into which both ends of the ram are inserted; a guide bar parallel to the ram, the guide bar having both ends inserted into retaining holes provided in the pair of cylinders; a guide attached to the ram and sliding along the guide bar while engaging with the guide bar; and a stroke sensor including a detection element and a linear detector extending in the axial direction of the ram that detects the position of the detection element, wherein the detection element is attached to one of the guide and the guide bar, and the linear detector is attached to the other of the guide and the guide bar.

[0058] According to the above configuration, the stroke sensor can detect the relative position of the detection element with respect to the linear detector as the ram stroke, and the ram stroke can be converted into the rudder angle. Moreover, because the detection element and linear detector of the stroke sensor are attached to the guide and guide bar, the stroke sensor, which is a sensor for detecting the rudder angle, can be adjusted before the steering gear is installed on the ship.

[0059] In a sixth aspect, from a third aspect, the present disclosure provides a steering gear comprising: a tiller fixed to a rudder stock; a ram provided with a pin that engages with the tiller; a first cylinder and a second cylinder into which both ends of the ram are inserted, respectively; and a stroke sensor including a detection element and a linear detector extending in the axial direction of the ram that detects the position of the detection element, wherein each of the first cylinder and the second cylinder includes a tubular portion and a bottom portion, the detection element is attached to one of the ram and the bottom portion of the first cylinder, and the linear detector is attached to the other of the ram and the bottom portion of the first cylinder.

[0060] According to the above configuration, the stroke sensor can detect the relative position of the detection element with respect to the linear detector as the ram stroke, and the ram stroke can be converted into a rudder angle. Moreover, because the detection element and linear detector of the stroke sensor are attached to the bottom of the ram and the first cylinder, the stroke sensor, which is a sensor for detecting the rudder angle, can be adjusted before the steering gear is installed on the ship.

[0061] 1A, 1B, 1C, 1D, 1E Steering gear 11 Rudder stock 2 Tiller 3 Ram 31 Pin 4A First cylinder 4B Second cylinder 41 Tubular part 42 Bottom part 44 Retaining hole 5 Guide bar 6 Guide 7 Bracket 8 Stroke sensor 81 Linear detector 84 Detection element

Claims

1. A steering gear comprising: a rudder fixed to a rudder stock; a ram provided with a pin which engages with the rudder; a pair of cylinders into which both ends of the ram are inserted; a bracket bridging the pair of cylinders to allow for fluctuations in the distance between the pair of cylinders; and a stroke sensor including a detection element and a linear detector extending in the axial direction of the ram for detecting the position of the detection element, wherein the detection element is attached to one of the ram and the bracket, and the linear detector is attached to the other of the ram and the bracket.

2. A steering gear as claimed in claim 1, further comprising: a guide bar parallel to the ram, both ends of which are inserted into retaining holes provided in the pair of cylinders; and a guide attached to the ram, which slides along the guide bar while engaging with the guide bar, and wherein the detection element or the linear detector is attached to the ram via the guide.

3. A steering gear as claimed in claim 1 or 2, wherein the pair of cylinders is a first cylinder and a second cylinder, one end of the bracket is fixed to the first cylinder, and the other end of the bracket is connected to the second cylinder so as to be slidable relative to the second cylinder.

4. A steering gear as claimed in claim 1 or 2, wherein both ends of said bracket are fixed to said pair of cylinders, and said bracket has an absorbing portion which is elastically deformable in the axial direction of said ram.

5. A steering gear comprising: a rudder fixed to a rudder stock; a ram provided with a pin which engages with the rudder; a pair of cylinders into which both ends of the ram are inserted; a guide bar parallel to the ram, the both ends of which are inserted into retaining holes provided in the pair of cylinders; a guide attached to the ram and engaging with the guide bar while sliding along the guide bar; and a stroke sensor including a detection element and a linear detector extending in the axial direction of the ram for detecting the position of the detection element, wherein the detection element is attached to one of the guide and the guide bar, and the linear detector is attached to the other of the guide and the guide bar.

6. A steering gear comprising: a rudder fixed to a rudder stock; a ram provided with a pin engaging with the rudder; a first cylinder and a second cylinder into which both ends of the ram are inserted, respectively; a stroke sensor including a detection element and a linear detector extending in the axial direction of the ram for detecting the position of the detection element, wherein each of the first cylinder and the second cylinder includes a tubular portion and a bottom portion, the detection element being attached to one of the ram and the bottom portion of the first cylinder, and the linear detector being attached to the other of the ram and the bottom portion of the first cylinder.

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