CA1218918A - Hydraulic control package for a marine steering system - Google Patents
Hydraulic control package for a marine steering systemInfo
- Publication number
- CA1218918A CA1218918A CA000480557A CA480557A CA1218918A CA 1218918 A CA1218918 A CA 1218918A CA 000480557 A CA000480557 A CA 000480557A CA 480557 A CA480557 A CA 480557A CA 1218918 A CA1218918 A CA 1218918A
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- CA
- Canada
- Prior art keywords
- steering
- pumps
- starboard
- pump
- fluid
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Abstract
ABSTRACT
A hydraulic control assembly is disclosed for the use in a marine steering system of the type having at least two steering pumps with each having port and starboard fluid outlets and a return inlet. A steering cylinder has a piston therein and port and starboard inlets for hydraulically moving the piston back and forth in the cylinder in response to fluid delivered from the pumps. Control valve means interconnects the port outlets of the pumps to the port inlet of the steering cylinder and the starboard outlets of the pumps to the starboard inlet of the steering cylinder and includes a return line connected to the return inlets of the pumps for controlling fluid flow between the pumps and the steering cylinder. The assembly is characterized by including flow divider means between the control valve means and the steering pumps for preventing the nonactive steering pump from motoring in response to steering fluid output of the active steering pump while allowing a limited amount of the steer-ing fluid output to flow to the nonactive steering pump.
FP-556A(Teleflex-M/I) DIV I
A hydraulic control assembly is disclosed for the use in a marine steering system of the type having at least two steering pumps with each having port and starboard fluid outlets and a return inlet. A steering cylinder has a piston therein and port and starboard inlets for hydraulically moving the piston back and forth in the cylinder in response to fluid delivered from the pumps. Control valve means interconnects the port outlets of the pumps to the port inlet of the steering cylinder and the starboard outlets of the pumps to the starboard inlet of the steering cylinder and includes a return line connected to the return inlets of the pumps for controlling fluid flow between the pumps and the steering cylinder. The assembly is characterized by including flow divider means between the control valve means and the steering pumps for preventing the nonactive steering pump from motoring in response to steering fluid output of the active steering pump while allowing a limited amount of the steer-ing fluid output to flow to the nonactive steering pump.
FP-556A(Teleflex-M/I) DIV I
Description
P-556 8~86-265D
This application is divided out of copending Canadian application ~o. 419,756, filed January 19, 1983.
The subject invention relates to a hydraulic control assembly or package for use in a marine steering system.
Tyically, a marine steering system includes a steering or helm pump attached to a steering wheel for directing fluid to oppos-ite ends of an actuating cylinder which, in turn, actuates the rudder to effect steering of the boat.
~ s will be appreciated, there is quite a distance between the helm steering pump and the hydraulic actua-ting cylinder for moving the rudder. Typical of a prior art system is one which includes a reservoir positioned somewhere on the boat between the steering helm pump and the actuating cylinder.
Fre~uently, the reservoir is pressurized with air so that the entire system is pressurized. In such systems air or gas may accummulate in the actuating cylinder and must be released or bled off. Typically, manually actuated pressure relief valves are attached to each end of the cylinder and, when opened, relieve the gas at the end of the cylinder, which gas passes to the atmosphere or back to the reservoir. During the bleeding operation, the reservoir is disconnected from the system and, after the bleeding is completed, the relief valves are closed, putting the reservoir back in-to the system.
The prior art systems also include various control valves for directing the fluid flow between the steering helm pump and the actuating cylinder.
FP-556A(Teleflex-M/I) DIV I - 1 -Most such steering systems also include various filters for removing contaminants from the hydraulic fluid.
Such filters frequently restrict the hydraulic fluid flow and, therefore, increase the effort required for steering.
According to the present inven-tion -there is provided a hydraulic control assembly for use in a marine steering system of the type having at least two steering pumps with each having port and starboard fluid outlets and a return inlet, a steering cylinder with a piston therein and port and starboard inle-ts for hydraulically moving the piston back and forth in the cy].inder in response to fluid delivered :~rom the pumps, control valve means lnterconnecting said port outlets of said pumps to said port inlet of said steering cylinder and said starboard outlets of said pumps to said starboard inlet of said steering cylinder and including a return line connected to said return inlets of said pumps for controlling fluid flow between the pumps and the steering cylinder, said assembly being characterized by including flow divider means between said control valve means and said ~0 steering pumps for preventing the nonactive steering pump from motoring in response to steering fluid output of the active steering pump while allowing a limited amount of the steering fluid output to flow to the nonactive steering pump, the flow divider means including a first shuttle-tee check valve having a first valve passage interconnecting the port ;
P-556 1~ 8 outlets of the steering pumps and a first outlet connected -to the control valve means with a first valve member movable back and forth to close the first valve passage to -the por-t outlet of the inactive pump in response to fluid output from the port outlet of the active pump and a second shuttle-tee check valve having a second valve passage interconnec-ting the starboard outlets of the steering pumps and a second outlet connected to the control valve means with a second valve member movable back and forth to close the second valve passage to the starboard outlet of the inactive pump in response -to fluid output from the starboard ou-tlet of the active pump.
The present invention will now be described by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
FIGURE 1 is a schematic view illus-trating a marine steering system, - 2a -~2~8~
FIGURE 2 is an enlarged cross-sectional view taken substantially along line 2-2 of FIGURE 4;
FIGURE 3 is a cross-sectional view through the valve body taken subs-tantially along line 3-3 of FIGURE 2;
FIGURE 4 is a side elevational view taken substantially along line 4-4 of FIGURE 2 but of a smaller scale and partially broken away and in cross section, and FIGURE 5 is a schematic view showing a steering assembly of the suject invention including a plurality of steering pumps.
~ marine steering system is generally shown at 10 in FIGURE 1. The steering system 10 is of the type havi.ng a helm ~teering pump 12 with port and starboard Eluid outlets 14 and 16, respectively, and return inlet 18.
The steering system 10 includes an actuating or steer-ing cylinder 20 with an actuating piston 22 slidably disposed therein with port and starboard inlets 2 4 and 26, respectively, for moving the piston 22 back and forth in the cylinder 20 in response to fluid delivered from the steering pump 12.
The hydraulic control assembly is generally shown at 30. The assembly includes a reservoir for supplying fluid to the steering system 10. The reservoir includes a tube 32, preferably a cylinder made of clear acrylic having first and second open ends. A metal cap member 34 is in sealing engage-ment with the first or top end of the tube 32. A valve body, generally indicated at 36, is in sealing engagement with the second or bottom end of the tube 32 to define the fluid ~2~
reservoir.
The hydraulic control assembly 30 also includes control valve means for controlling the fluid flow in the system 10 and the valve body 36 includes or houses the control valve means.
The cap member 34 includes a cylindrical or circular insert portion 38 extending into and in sealing engagement with the interior of the tube 32 adjacent the top end thereof.
More specifically, an annular or circular seal 40 is disposed between the central insert 38 and the interior wall of the acrylic tube 32. In a similar ~z~
fashion, the valve body 36 includes an insert por-tion 42 extending into and in sealing engagement with the interior of the tube 32 adjacent the bottom end thereof, there being an annular seal 44 disposed between the central 5 insert portion 42 and the interior wall of the acry]ic tube 32. The cap member 34 includes an abutment flange 46 which is square or four-sided to define round corners.
The abutment flange 46 extends radially from the insert portion 38 and engages the end surface of the top of the 10 tube 32. In a similar fashionl the valve body includes an abutment flange 48 which is square or four-sided to define round corners and extends radially from the inser-t portion 42 thereof to engage the bottom end surface of the tube 32.
A plurality of tie rods 50 interconnect t,he cap member 34 and the valve body 36 for urging the cap member 34 and the valve body 36 into engagement wih -the top and bottom ends of the tube 32. There are four tie rods 50 and each tie rod extends through one of the corners of the 20 abutment flanges 46 and 48. The tie rods are threaded at each end and include nuts for tensioning the respective tie rods 50.
The valve body 36 includes a central metal portion 52 extending from the abutment flange 48 thereof in a 25 direction away from the bottom or second end of the tube 32. The valve body also includes a pair of identical side portions 54 extending along opposite sides of the central portion 52 and connected thereto by bolts 56, one of which is illustrated in FIGURE 2. The side portions 54 are 30 preferably made of a plas-tic, such as nylon. Thus, the side portions 54 are removably attached to the central portion 52 by bolts 56.
The central portion 52 includes a reservoir inlet passage 58 extending to a first opening into the tube 34.
35 A portion of the reservoir inlet passage 58 is plugged by a threaded plug 60. A first control tube 62 is threaded 8~
into the opening of the reservoir inlet passage into the tube 32. The central portion 52 also includes a pump outlet passage extending from a second opening into the tube 32 to the pump return outle-t line 18. A second 5 control tube 66 is threaded into the opening for the pump outlet passage. The cap 34 forms the top of the reservoir and the valve body 36 forms the bottom of the reservoir.
Accordingly, the control tubes 62 and 66 ex-tend upwardly from the bottom of the reservoir tank into the reservoir.
10 The first control tube 62 which provides an inlet into the reservoir tank of hydraulic fluid from the system is longer in length than the second con-trol tube 66 forming the exit tube to the steeriny pump inlet 18. Accordingly, contaminants in the hydraulic fluid entering the tube 62 15 will be dispersed -throughou-t -the hydraulic fluid in the reservoir tank to fall to -the bottom or settle on the bottom of the reservoir about the control tubes 62 and 66 so as to be prevented from entering the ~ump outlet control tube 66. In other words, the end of the tube 66 20 is high enough above the bottom of the tank so that contaminants settled on the bottom of the tank will not enter the tube 66 and the system. The arrangement of the tubes 62 and 66, therefore, eliminates the need for a filter in the system which could increase the steering 25 resistance.
Each of the side portions 54 includes a pump inlet passage 68 communicating with the central portion 52 for receiving fluid from- the pump outlets 14 and 16 7 respectively. Each of the side portions 54 also includes 30 a cylinder passage 70 for establishing fluid communication between the central portion 52 and one of the steering cylinder inlets 24 and 26. A check valve 72 is disposed in each cylinder passage 70 in each of the side portions 54.
The central portion 52 has a shuttle bore 74 extending completely therethrough between the side portions 54 and communicating with the pump inlet passages 68. A shuttle valve means or members 76 are slidably 5 disposed in the shuttle bore 74 for controlling the fluid flow therethrough. The central portion also has a spool bore 78 extending therethrough between the side portions 54 and communicating with the cylinder passages 70. A
spool valve means or member 80 is slidably disposed in the 10 spool bore to perform a controlling function.
Each of the side portions 54 includes a first pocket 82 therein about the cylinder passage 70 and facing the spool bore 78 at the end thereof. A first valve seat 84 ls disposed in each pocket 82 and engages the side of the 1~ central portion 52. The check valve 72 includes a round ball disposed in the cylinder passage 70 with a spring associated therewith and disposed around a projection in the side portion for reacting between the side portion 54 and the ball for urging the ball into and in sealing 20 engagement with the associate valve seat 84.
As alluded to above, the side portions 54 are preferably made of a plastic, such as nylon, and include metal connectors or fasteners 86 at each of the pump inlet passages 68 and at each of the cylinder passages 70. Each 25 connector or fitting 86 has one end completely embedded in the plastic material of the side portions 54 with the other end extending therefrom and adapted by nuts to be connected to a fluid line. Specifically, the connectors are of the type into which the end of a tube is inserted 30 with the connectors being tightened down to force an annular flexible seal into engagement with the exterior of the tube. As shown, each of the connectors includes an insert 88 which prevents contaminants from entering into the system dùring shipment, the insert 88 being removed 35 prior to attaching the end of a tube to the connector. A
~2~9~3 similar connector 90 threadedly engages the central portion 52 of the valve body and similarly attaches to a fluid line 18 leading to the helm pump 12.
The central portion 52 has a relief cavity 92 5 extending therethrough between the side portions 54. Each side portion 54 has a relief passage 94 communicating between the cylinder passage 70 and the relief cavity 92 in the central portion 52. Each side portion 54 has a second pocket therein about the relief passage 94 and 10 facing the relief cavity 92 for receiving a second valve seat 96. Each valve seat 96 is disposed in the pocket and engages the side face of the central portion 52. ~ relief valve assembly 92 is disposed in each of the opposite ends of the relief cavity 92 and lncludes a spring biased ball 15 engaging the second valve seat 96.
The central portion 52 includes the passages 100 and 102 communicating between the shuttle bore 74 and the spool bore 78 with the openings thereof being controlled by the shuttle valve members 76. As described 20 hereinbefore, a portion of the reservoir inlet passage 58 is a passage extending between the relief cavity 92 and the reservoir inlet.
The spool valve 80 includes extensions extending from each end thereof for opening the check valves 72.
As alluded to hereinbefore, the reservoir is closed and includes filling means defined by the plug 104 and the one-way inlet valve 106 in the top or cap 34 of the reservoir for filling the reservoir with hydraulic fluid and for pressurizing the reservoir with a gas such as air.
30 The plug 104 may be threaded out of engagement with the cap 34 for introducing hydraulic fluid into the reservoir.
The pressure inlet 106 is of the type utilized with pneumatic tires, such as automotive tires, for inflating tires. Also disposed in the cap member 34 is a pressure 35 gauge means 108 for indicating the pressure in the system 10 .
~L2~
Instead of the pressure gauge 108 being connected to the cap member 34 or, in addition to the pressure gauge 108, a pressure gauge 108', as shown in FIGURE 1, may be connected to the return line to the steering pump 12 with 5 the gauge 108' actually being disposed on the instrument panel whereby the boat operator has an immediate indication of the system pressure.
The assembly also includes the brackets 110 which are held in place by tie rods 50 for attaching the assembly or 10 mounting the assembly to a support structure.
The operation of the system is best illustrated in FIGURE 1 wherein the pump 12 is providing pressure in the line 16 to the passage 68 in the valve body 36. The fluid pressure in the passage 68 acts upon the right-h~nd valve 15 member 76 rnoving it to the left as indicated. Fluid pr~ssure Erom the line 68 passes through the passage lO0 to the spool bore 78. I'he fluid pressure in the bore 78 moves the spool valve 80 to the left whereby the check valve 72 on the left is opened, allowing return fluid flow 20 from the cylinder 20 through the passage 102 on the left and into the tube 62 of the reservoir. Pressure on the right of spool valve 80 also opens the check valve 72 on the .ight to allow flow through the conduit 26 to the hydraulic cylinder 20 thereby moving the piston to the 25 left, as illustrated. The pump 12, of course, is being fed hydraulic fluid from the reservoir through the tube 66 and the pump inlet 18.
If the direc-tion of steering is reversed, the valves all move to the right in response to fluid pressure 30 produced by the pump 12 in the pump outlet 14 and the components all work in reverse.
Although not shown schematically in FIGURE 1, the system does include high pressure relief valves 98 which open the cylinder passages 70 to the relief cavity 92 and 35 the passage 58 extending back to the reservoir inlet tube ~2~L1391~
62. In other words, if the pressure in the cylinder passage 70 becomes too high, the relief valves 9~ will relieve the pressure to the reservoir.
The assembly shown schematically in FIGURE 5 includes 5 the hydraulic control assembly 30~ as described above, associated with the steering cylinder 20 with the port and starboard inlets 24 and 26. The system in FIGURE 5 includes a second steering pump 12' having the port and starboard fluid outlets 14' and 16'. The line 18 is 10 connected to the return inlet of the pump 12' with the pump 12' connected by line 18' to the return inlet of steering pump 12. The assembly of FIGURE 5 includes flow divider means between the control valve means 36 and the steering pumps 12 and 12' for preventing the nonactive 15 steering pump from motoring in response to steering fluid output of the active steering pump while allowing a limited amount of the steering fluid output to flow to the nonactive steering pump. More specifically, the flow divider means includes a first shuttle-tee check valve 120 20 having a first valve passage interconnecting the port outlets 14 and 14' of the steering pumps 12 and 12' and a first outlet 121 connected to the control valve means 36.
A first ball valve member 122 is movable back and forth in the first valve passage to close the first valve passage 25 to the port outlet 14 or 14' of the inactive pump in response to fluid output from the port outlet 14 or 14' of the active pump. In a similar fashion, the flow divider means includes a second shuttle-tee check valve 124 having a second valve passage interconnecting the starboard 30 outlet 16 and 16' of the steering pumps 12 and 12' and a second outlet 125 connected to the control valve means 36.
A second ball valve member 126 is movable back and forth in the second valve passage to close the second valve passage to the starboard outlet 16 or 16' of the inactive 35 pump in response to fluid output from the starboard outlet 16 or 16' of the active pump.
~2~
In addition, the flow divider means includes a first bypass passage 127 interconnecting the port outlets 14 and 14' for allowing a restricted flow of fluid to bypass the first shuttle-tee check valve 120. Similarly, a second 5 bypass passage 128 interconnects the starboard outlets 16 and 16' for allowing a restricted flow of fluid to bypass the second shuttle-tee valve 124. Each of the bypass passages 127 and 128 includes a calibrated flow control restriction to limit the volume flow rate to a 10 predetermined range.
The two steering pumps 12 and 12' may be two pumps connected to a steering wheel or one of the steering pumps may be associated with an auto pilot. Assuming that the steering pump 12 is the active pump by being manually 15 actuated for producing steering fluid pressure in the starboard outlet 16, the fluid will flow into the shuttle-tee check valve 124 moving the valve member 126 to the left, as illustrated, for preventing fluid flow through the shuttle-tee check valve 24 and into the starboard 20 outlet line 16' leading to the second steering pump 12'.
This will prevent the second steering pump 12' from motoring or turning in response to the output of the first steering pump 12. The output from the first steering pump 12 will pass through the shuttle-tee check valve 124 and 25 out the outlet 125 thereof to the passage 68 in the control valve means 36, as hereinbefore described. At the same time, a restricted flow passes through the bypass passage 128 and the calibrated restriction 130 to the starboard outlet 16' of the nonactive pump 12'. This 30 compensates for the residual pressure in the lines, particularly when the steering direction is changed frequently. If the active steering pump 12 is rotated in the opposite direction, the system would operate in reverse with'the check ball member 122 moving to the 35 right~ Additionally, should the steering pump 12' become the active pump for an output in the starboard outlet 16', ~L2~89~
the check ball member 126 would move to the right and the bypass flow in the passage 128 would be in the reverse direction from outlet 16' to outlet 16.
In actual practice, when using 300 psi in the system, the restrictions 130 have been calibrated to allow a rate of flow in the predetermined range of between 50 and 150 milliliters per minute. If the bypass leakage in the passages 127 and 128 is too small, the two shuttle members or plungers 76 in the control valve means 36 could remain closed on both sides at the same time. If the bypass Elow is too high, the nonoperated or inactive skeerin~ pump will motor or turn in response to activation of the other steering pump.
By utilizing the concept shown in FIGURE 5, the steering pumps 12 and 12' need not have any valves whatsoever associated with them to control flow therethrough and soft lines may be used in the system.
This application is divided out of copending Canadian application ~o. 419,756, filed January 19, 1983.
The subject invention relates to a hydraulic control assembly or package for use in a marine steering system.
Tyically, a marine steering system includes a steering or helm pump attached to a steering wheel for directing fluid to oppos-ite ends of an actuating cylinder which, in turn, actuates the rudder to effect steering of the boat.
~ s will be appreciated, there is quite a distance between the helm steering pump and the hydraulic actua-ting cylinder for moving the rudder. Typical of a prior art system is one which includes a reservoir positioned somewhere on the boat between the steering helm pump and the actuating cylinder.
Fre~uently, the reservoir is pressurized with air so that the entire system is pressurized. In such systems air or gas may accummulate in the actuating cylinder and must be released or bled off. Typically, manually actuated pressure relief valves are attached to each end of the cylinder and, when opened, relieve the gas at the end of the cylinder, which gas passes to the atmosphere or back to the reservoir. During the bleeding operation, the reservoir is disconnected from the system and, after the bleeding is completed, the relief valves are closed, putting the reservoir back in-to the system.
The prior art systems also include various control valves for directing the fluid flow between the steering helm pump and the actuating cylinder.
FP-556A(Teleflex-M/I) DIV I - 1 -Most such steering systems also include various filters for removing contaminants from the hydraulic fluid.
Such filters frequently restrict the hydraulic fluid flow and, therefore, increase the effort required for steering.
According to the present inven-tion -there is provided a hydraulic control assembly for use in a marine steering system of the type having at least two steering pumps with each having port and starboard fluid outlets and a return inlet, a steering cylinder with a piston therein and port and starboard inle-ts for hydraulically moving the piston back and forth in the cy].inder in response to fluid delivered :~rom the pumps, control valve means lnterconnecting said port outlets of said pumps to said port inlet of said steering cylinder and said starboard outlets of said pumps to said starboard inlet of said steering cylinder and including a return line connected to said return inlets of said pumps for controlling fluid flow between the pumps and the steering cylinder, said assembly being characterized by including flow divider means between said control valve means and said ~0 steering pumps for preventing the nonactive steering pump from motoring in response to steering fluid output of the active steering pump while allowing a limited amount of the steering fluid output to flow to the nonactive steering pump, the flow divider means including a first shuttle-tee check valve having a first valve passage interconnecting the port ;
P-556 1~ 8 outlets of the steering pumps and a first outlet connected -to the control valve means with a first valve member movable back and forth to close the first valve passage to -the por-t outlet of the inactive pump in response to fluid output from the port outlet of the active pump and a second shuttle-tee check valve having a second valve passage interconnec-ting the starboard outlets of the steering pumps and a second outlet connected to the control valve means with a second valve member movable back and forth to close the second valve passage to the starboard outlet of the inactive pump in response -to fluid output from the starboard ou-tlet of the active pump.
The present invention will now be described by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
FIGURE 1 is a schematic view illus-trating a marine steering system, - 2a -~2~8~
FIGURE 2 is an enlarged cross-sectional view taken substantially along line 2-2 of FIGURE 4;
FIGURE 3 is a cross-sectional view through the valve body taken subs-tantially along line 3-3 of FIGURE 2;
FIGURE 4 is a side elevational view taken substantially along line 4-4 of FIGURE 2 but of a smaller scale and partially broken away and in cross section, and FIGURE 5 is a schematic view showing a steering assembly of the suject invention including a plurality of steering pumps.
~ marine steering system is generally shown at 10 in FIGURE 1. The steering system 10 is of the type havi.ng a helm ~teering pump 12 with port and starboard Eluid outlets 14 and 16, respectively, and return inlet 18.
The steering system 10 includes an actuating or steer-ing cylinder 20 with an actuating piston 22 slidably disposed therein with port and starboard inlets 2 4 and 26, respectively, for moving the piston 22 back and forth in the cylinder 20 in response to fluid delivered from the steering pump 12.
The hydraulic control assembly is generally shown at 30. The assembly includes a reservoir for supplying fluid to the steering system 10. The reservoir includes a tube 32, preferably a cylinder made of clear acrylic having first and second open ends. A metal cap member 34 is in sealing engage-ment with the first or top end of the tube 32. A valve body, generally indicated at 36, is in sealing engagement with the second or bottom end of the tube 32 to define the fluid ~2~
reservoir.
The hydraulic control assembly 30 also includes control valve means for controlling the fluid flow in the system 10 and the valve body 36 includes or houses the control valve means.
The cap member 34 includes a cylindrical or circular insert portion 38 extending into and in sealing engagement with the interior of the tube 32 adjacent the top end thereof.
More specifically, an annular or circular seal 40 is disposed between the central insert 38 and the interior wall of the acrylic tube 32. In a similar ~z~
fashion, the valve body 36 includes an insert por-tion 42 extending into and in sealing engagement with the interior of the tube 32 adjacent the bottom end thereof, there being an annular seal 44 disposed between the central 5 insert portion 42 and the interior wall of the acry]ic tube 32. The cap member 34 includes an abutment flange 46 which is square or four-sided to define round corners.
The abutment flange 46 extends radially from the insert portion 38 and engages the end surface of the top of the 10 tube 32. In a similar fashionl the valve body includes an abutment flange 48 which is square or four-sided to define round corners and extends radially from the inser-t portion 42 thereof to engage the bottom end surface of the tube 32.
A plurality of tie rods 50 interconnect t,he cap member 34 and the valve body 36 for urging the cap member 34 and the valve body 36 into engagement wih -the top and bottom ends of the tube 32. There are four tie rods 50 and each tie rod extends through one of the corners of the 20 abutment flanges 46 and 48. The tie rods are threaded at each end and include nuts for tensioning the respective tie rods 50.
The valve body 36 includes a central metal portion 52 extending from the abutment flange 48 thereof in a 25 direction away from the bottom or second end of the tube 32. The valve body also includes a pair of identical side portions 54 extending along opposite sides of the central portion 52 and connected thereto by bolts 56, one of which is illustrated in FIGURE 2. The side portions 54 are 30 preferably made of a plas-tic, such as nylon. Thus, the side portions 54 are removably attached to the central portion 52 by bolts 56.
The central portion 52 includes a reservoir inlet passage 58 extending to a first opening into the tube 34.
35 A portion of the reservoir inlet passage 58 is plugged by a threaded plug 60. A first control tube 62 is threaded 8~
into the opening of the reservoir inlet passage into the tube 32. The central portion 52 also includes a pump outlet passage extending from a second opening into the tube 32 to the pump return outle-t line 18. A second 5 control tube 66 is threaded into the opening for the pump outlet passage. The cap 34 forms the top of the reservoir and the valve body 36 forms the bottom of the reservoir.
Accordingly, the control tubes 62 and 66 ex-tend upwardly from the bottom of the reservoir tank into the reservoir.
10 The first control tube 62 which provides an inlet into the reservoir tank of hydraulic fluid from the system is longer in length than the second con-trol tube 66 forming the exit tube to the steeriny pump inlet 18. Accordingly, contaminants in the hydraulic fluid entering the tube 62 15 will be dispersed -throughou-t -the hydraulic fluid in the reservoir tank to fall to -the bottom or settle on the bottom of the reservoir about the control tubes 62 and 66 so as to be prevented from entering the ~ump outlet control tube 66. In other words, the end of the tube 66 20 is high enough above the bottom of the tank so that contaminants settled on the bottom of the tank will not enter the tube 66 and the system. The arrangement of the tubes 62 and 66, therefore, eliminates the need for a filter in the system which could increase the steering 25 resistance.
Each of the side portions 54 includes a pump inlet passage 68 communicating with the central portion 52 for receiving fluid from- the pump outlets 14 and 16 7 respectively. Each of the side portions 54 also includes 30 a cylinder passage 70 for establishing fluid communication between the central portion 52 and one of the steering cylinder inlets 24 and 26. A check valve 72 is disposed in each cylinder passage 70 in each of the side portions 54.
The central portion 52 has a shuttle bore 74 extending completely therethrough between the side portions 54 and communicating with the pump inlet passages 68. A shuttle valve means or members 76 are slidably 5 disposed in the shuttle bore 74 for controlling the fluid flow therethrough. The central portion also has a spool bore 78 extending therethrough between the side portions 54 and communicating with the cylinder passages 70. A
spool valve means or member 80 is slidably disposed in the 10 spool bore to perform a controlling function.
Each of the side portions 54 includes a first pocket 82 therein about the cylinder passage 70 and facing the spool bore 78 at the end thereof. A first valve seat 84 ls disposed in each pocket 82 and engages the side of the 1~ central portion 52. The check valve 72 includes a round ball disposed in the cylinder passage 70 with a spring associated therewith and disposed around a projection in the side portion for reacting between the side portion 54 and the ball for urging the ball into and in sealing 20 engagement with the associate valve seat 84.
As alluded to above, the side portions 54 are preferably made of a plastic, such as nylon, and include metal connectors or fasteners 86 at each of the pump inlet passages 68 and at each of the cylinder passages 70. Each 25 connector or fitting 86 has one end completely embedded in the plastic material of the side portions 54 with the other end extending therefrom and adapted by nuts to be connected to a fluid line. Specifically, the connectors are of the type into which the end of a tube is inserted 30 with the connectors being tightened down to force an annular flexible seal into engagement with the exterior of the tube. As shown, each of the connectors includes an insert 88 which prevents contaminants from entering into the system dùring shipment, the insert 88 being removed 35 prior to attaching the end of a tube to the connector. A
~2~9~3 similar connector 90 threadedly engages the central portion 52 of the valve body and similarly attaches to a fluid line 18 leading to the helm pump 12.
The central portion 52 has a relief cavity 92 5 extending therethrough between the side portions 54. Each side portion 54 has a relief passage 94 communicating between the cylinder passage 70 and the relief cavity 92 in the central portion 52. Each side portion 54 has a second pocket therein about the relief passage 94 and 10 facing the relief cavity 92 for receiving a second valve seat 96. Each valve seat 96 is disposed in the pocket and engages the side face of the central portion 52. ~ relief valve assembly 92 is disposed in each of the opposite ends of the relief cavity 92 and lncludes a spring biased ball 15 engaging the second valve seat 96.
The central portion 52 includes the passages 100 and 102 communicating between the shuttle bore 74 and the spool bore 78 with the openings thereof being controlled by the shuttle valve members 76. As described 20 hereinbefore, a portion of the reservoir inlet passage 58 is a passage extending between the relief cavity 92 and the reservoir inlet.
The spool valve 80 includes extensions extending from each end thereof for opening the check valves 72.
As alluded to hereinbefore, the reservoir is closed and includes filling means defined by the plug 104 and the one-way inlet valve 106 in the top or cap 34 of the reservoir for filling the reservoir with hydraulic fluid and for pressurizing the reservoir with a gas such as air.
30 The plug 104 may be threaded out of engagement with the cap 34 for introducing hydraulic fluid into the reservoir.
The pressure inlet 106 is of the type utilized with pneumatic tires, such as automotive tires, for inflating tires. Also disposed in the cap member 34 is a pressure 35 gauge means 108 for indicating the pressure in the system 10 .
~L2~
Instead of the pressure gauge 108 being connected to the cap member 34 or, in addition to the pressure gauge 108, a pressure gauge 108', as shown in FIGURE 1, may be connected to the return line to the steering pump 12 with 5 the gauge 108' actually being disposed on the instrument panel whereby the boat operator has an immediate indication of the system pressure.
The assembly also includes the brackets 110 which are held in place by tie rods 50 for attaching the assembly or 10 mounting the assembly to a support structure.
The operation of the system is best illustrated in FIGURE 1 wherein the pump 12 is providing pressure in the line 16 to the passage 68 in the valve body 36. The fluid pressure in the passage 68 acts upon the right-h~nd valve 15 member 76 rnoving it to the left as indicated. Fluid pr~ssure Erom the line 68 passes through the passage lO0 to the spool bore 78. I'he fluid pressure in the bore 78 moves the spool valve 80 to the left whereby the check valve 72 on the left is opened, allowing return fluid flow 20 from the cylinder 20 through the passage 102 on the left and into the tube 62 of the reservoir. Pressure on the right of spool valve 80 also opens the check valve 72 on the .ight to allow flow through the conduit 26 to the hydraulic cylinder 20 thereby moving the piston to the 25 left, as illustrated. The pump 12, of course, is being fed hydraulic fluid from the reservoir through the tube 66 and the pump inlet 18.
If the direc-tion of steering is reversed, the valves all move to the right in response to fluid pressure 30 produced by the pump 12 in the pump outlet 14 and the components all work in reverse.
Although not shown schematically in FIGURE 1, the system does include high pressure relief valves 98 which open the cylinder passages 70 to the relief cavity 92 and 35 the passage 58 extending back to the reservoir inlet tube ~2~L1391~
62. In other words, if the pressure in the cylinder passage 70 becomes too high, the relief valves 9~ will relieve the pressure to the reservoir.
The assembly shown schematically in FIGURE 5 includes 5 the hydraulic control assembly 30~ as described above, associated with the steering cylinder 20 with the port and starboard inlets 24 and 26. The system in FIGURE 5 includes a second steering pump 12' having the port and starboard fluid outlets 14' and 16'. The line 18 is 10 connected to the return inlet of the pump 12' with the pump 12' connected by line 18' to the return inlet of steering pump 12. The assembly of FIGURE 5 includes flow divider means between the control valve means 36 and the steering pumps 12 and 12' for preventing the nonactive 15 steering pump from motoring in response to steering fluid output of the active steering pump while allowing a limited amount of the steering fluid output to flow to the nonactive steering pump. More specifically, the flow divider means includes a first shuttle-tee check valve 120 20 having a first valve passage interconnecting the port outlets 14 and 14' of the steering pumps 12 and 12' and a first outlet 121 connected to the control valve means 36.
A first ball valve member 122 is movable back and forth in the first valve passage to close the first valve passage 25 to the port outlet 14 or 14' of the inactive pump in response to fluid output from the port outlet 14 or 14' of the active pump. In a similar fashion, the flow divider means includes a second shuttle-tee check valve 124 having a second valve passage interconnecting the starboard 30 outlet 16 and 16' of the steering pumps 12 and 12' and a second outlet 125 connected to the control valve means 36.
A second ball valve member 126 is movable back and forth in the second valve passage to close the second valve passage to the starboard outlet 16 or 16' of the inactive 35 pump in response to fluid output from the starboard outlet 16 or 16' of the active pump.
~2~
In addition, the flow divider means includes a first bypass passage 127 interconnecting the port outlets 14 and 14' for allowing a restricted flow of fluid to bypass the first shuttle-tee check valve 120. Similarly, a second 5 bypass passage 128 interconnects the starboard outlets 16 and 16' for allowing a restricted flow of fluid to bypass the second shuttle-tee valve 124. Each of the bypass passages 127 and 128 includes a calibrated flow control restriction to limit the volume flow rate to a 10 predetermined range.
The two steering pumps 12 and 12' may be two pumps connected to a steering wheel or one of the steering pumps may be associated with an auto pilot. Assuming that the steering pump 12 is the active pump by being manually 15 actuated for producing steering fluid pressure in the starboard outlet 16, the fluid will flow into the shuttle-tee check valve 124 moving the valve member 126 to the left, as illustrated, for preventing fluid flow through the shuttle-tee check valve 24 and into the starboard 20 outlet line 16' leading to the second steering pump 12'.
This will prevent the second steering pump 12' from motoring or turning in response to the output of the first steering pump 12. The output from the first steering pump 12 will pass through the shuttle-tee check valve 124 and 25 out the outlet 125 thereof to the passage 68 in the control valve means 36, as hereinbefore described. At the same time, a restricted flow passes through the bypass passage 128 and the calibrated restriction 130 to the starboard outlet 16' of the nonactive pump 12'. This 30 compensates for the residual pressure in the lines, particularly when the steering direction is changed frequently. If the active steering pump 12 is rotated in the opposite direction, the system would operate in reverse with'the check ball member 122 moving to the 35 right~ Additionally, should the steering pump 12' become the active pump for an output in the starboard outlet 16', ~L2~89~
the check ball member 126 would move to the right and the bypass flow in the passage 128 would be in the reverse direction from outlet 16' to outlet 16.
In actual practice, when using 300 psi in the system, the restrictions 130 have been calibrated to allow a rate of flow in the predetermined range of between 50 and 150 milliliters per minute. If the bypass leakage in the passages 127 and 128 is too small, the two shuttle members or plungers 76 in the control valve means 36 could remain closed on both sides at the same time. If the bypass Elow is too high, the nonoperated or inactive skeerin~ pump will motor or turn in response to activation of the other steering pump.
By utilizing the concept shown in FIGURE 5, the steering pumps 12 and 12' need not have any valves whatsoever associated with them to control flow therethrough and soft lines may be used in the system.
Claims (3)
1. A hydraulic control assembly for use in a marine steering system of the type having at least two steering pumps with each having port and starboard fluid outlets and a return inlet, a steering cylinder with a piston therein and port and starboard inlets for hydraulically moving the piston back and forth in the cylinder in response to fluid delivered from the pumps, control valve means interconnecting said port outlets of said pumps to said port inlet of said steering cylinder and said starboard outlets of said pumps to said starboard inlet of said steering cylinder and including a return line connected to said return inlets of said pumps for controlling fluid flow between the pumps and the steering cylinder, said assembly being characterized by including flow divider means between said control valve means and said steering pumps for preventing the nonactive steering pump from motoring in response to steering fluid output of the active steering pump while allowing a limited amount of the steering fluid output to flow to the nonactive steering pump, the flow divider means including a first shuttle-tee check valve having a first valve passage interconnecting the port outlets of the steering pumps and a first outlet connected to the control valve means with a first valve member movable back and forth to close the first valve passage to the port outlet of the inactive pump in response to fluid output from the port outlet of the active pump and a second shuttle-tee check valve having a second valve passage interconnecting the starboard outlets of the steering pumps and a second outlet connected to the control valve means with a second valve member movable back and forth to close the second valve passage to the starboard outlet of the inactive pump in response to fluid output from the starboard outlet of the active pump.
2. An assembly as set forth in claim 1 further characterized by said flow divider means including a first bypass passage interconnecting said port outlets for allowing a restricted flow of fluid to bypass said first shuttle-tee check valve and a second bypass passage interconnecting said starboard outlets for allowing a restricted flow of fluid to bypass said second shuttle-tee check valve.
3. An assembly as set forth in claim 2 further characterized by each of said bypass passages including a calibrated flow control for limiting flow rate to a predetermined range.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000480557A CA1218918A (en) | 1982-02-18 | 1985-05-01 | Hydraulic control package for a marine steering system |
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/349,734 US4449470A (en) | 1982-02-18 | 1982-02-18 | Hydraulic control package for a marine steering system |
| US349,734 | 1982-02-18 | ||
| CA000419756A CA1193174A (en) | 1982-02-18 | 1983-01-19 | Hydraulic control package for a marine steering system |
| CA000480557A CA1218918A (en) | 1982-02-18 | 1985-05-01 | Hydraulic control package for a marine steering system |
Related Parent Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000419756A Division CA1193174A (en) | 1982-02-18 | 1983-01-19 | Hydraulic control package for a marine steering system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1218918A true CA1218918A (en) | 1987-03-10 |
Family
ID=25669915
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000480557A Expired CA1218918A (en) | 1982-02-18 | 1985-05-01 | Hydraulic control package for a marine steering system |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1218918A (en) |
-
1985
- 1985-05-01 CA CA000480557A patent/CA1218918A/en not_active Expired
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| Date | Code | Title | Description |
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| MKEX | Expiry |