KR820000855B1 - Hydraulic control system for operating multiple remote devices with a minimun number of connecting conduits - Google Patents

Abstract

The hydraulic control circuit is partic. for use with multi-function hydraulic devices, such as for industrial lift truck attachments. A combination of valves operate two or more hydrualic systems. A minimum number of hydraulic conduits are required to connect the main hydraulic system to the hydraulic devices, as from a lift truck to an attachment supporting carriage on a lift truck upright, and no electric lines are required to be connected to switching devices between the hydraulic devices, such as to solenoid-operated valves.

Description

Hydraulic controls to operate multifunction remotes with minimal connection conduits

1 is a partial perspective view of a lift truck with conventional attachments installed on the suspension.

2 is a diagram of a main hydraulic device of a truck connected to a multifunction remote device showing an embodiment of the present invention, which shows a central portion and is coupled with two functional attachments.

3-5 show that the FIG. 2 device operates in different conditions.

6 shows that the associating device of the FIG. 2 device represents one operating condition and is installed for operating three functional attachments.

7 and 8 show that the apparatus of FIG. 6 is operating under different conditions.

9 and 10 show that two functional attachments according to the invention operate in two different ways.

A multifunctional hydraulic system operating in one or several directions with respect to the connected hydraulic system requires that the connected hydraulic conduit be movable because the end of the hydraulic conduit is continuously connected to the moving device.

Examples of such remote devices are devices installed for operation from the end of a lift crane or boom mechanism or other device, and multifunctional attachments installed to lift the lift lift truck upright.

The present invention relates to a hydraulic control device for a lift truck attachment, but the subject matter is much broader than this name.

As is known in the industry of lift trucks, the various modifications of the attachments are supported by carriages (usually known as fork carriages), which are raised on the lifting carriages to perform the various functions of the carriages and the islands. to design the support.

The attachments are for example side shifting clamps, rotating roll clamps side loaders and the like.

Thus, the attachments, depending on their function and operation, are connected by a number of flexible hydraulic conduits and sometimes wires connected to the solenoid valves of the lift carriage from the truck hydraulics to the attachments to vertically move the conduit and the conduits and wires around them. Should be. Various devices have been devised to improve the passage of hoses and wires in this case, and US Pat. Described in

As is known in the art, the attachment of hydraulic conduits connected to the stays and / or attachments requiring wires to move the lift carriage is inconvenient in many ways.

These inconveniences include operator's visual disturbances through shallows, rupture and cutting of hydraulic conduits and wires, high production costs or other issues. A design for reducing the number of such conduits connected to eight or more of the recesses required for a lift truck attachment is described in US Patent No. 3,692,198 owned by the present applicant.

It has a structure that reduces the number of conduits connected to the staylight to about three on the side shifting clamp attachment.

The present invention relates to a hydraulic system in which only two hydraulic conduits having various functions in the lift truck are connected to the sole, and there is no need for electric wires for connecting the carriage with the attachment and the solenoid valve.

In a hydraulic control system in which the multifunction remote is operated by only two hydraulic conduits connected to the remote device from the main hydraulic device, the control device operates under one selected condition among several functions operated by the hydraulic pressure of the remote device. It consists of a combination of valve devices combined to

It is an object of the present invention to provide a hydraulic apparatus for reducing the number of hydraulic conduits connected to a remote multifunction apparatus.

When described in detail with reference to the drawings as follows.

(10) is a lift-up assembly installed to raise the side shifting clamp attachment (14) having a pair of hydraulic cylinder actuators (16) and (18) connected to the clamp arms (20) and (22) moving horizontally and vertically. 12) is an industrial lift truck having a known structure located on the front side.

Since the hydraulics of the truck are connected to the actuators 16 and 18 as described above, the clamp arms 20 and 22 are respectively operated back and forth according to the fixed or unfixed point between them at the driver's position. It operates in the same direction in which the load is lifted obliquely in either direction across the centerline of the truck.

The attachment 14 shows only one of the multifunctional hydraulic attachments used for the lift truck, or the multifunctional hydraulic devices used for other types of vehicles or other purposes.

The attachment 14 also had two functions, such as side shifting and clamping operation, while the attachment, also known as side shifting rotating clamp, has three functions: side shifting, clamping and rotating.

At least four hydraulic conduits and one wire shall be connected to the staylight to perform the required operation on the latter attachment.

In the present invention, however, only two hydraulic conduits are connected to the stay and no wires are required to operate the trifunctional attachment. In addition, the present invention utilizes a hydraulic conduit of a hydraulic control device connected to a remote hydraulic device, or only two hydraulic conduits are connected to a telescopic boom tuck and no wires are required.

2-5 show a pair of opposing actuating cylinders 30 and 32, and the shift cylinder depicts various modes of operation of the bifunctional attachment shown as 34. In FIG.

The main hydraulic device is known.

The apparatus consists of a supply pump 36 connected to a storage tank 38 which is installed for circulation under constant pressure via a safety valve 40 by means of conduits 42 and 44.

A single acting lift cylinder assembly 46 which raises the attachment 14 at the suspension 12 is connected to the valve 50 by a conduit 52 and at the bottom of the inclined serpent ( A pair of double acting tilt cylinders 54 for 12 is connected to the directional control valve 56 by conduits 58 and 60 and auxiliary conduits 62 and 64.

The valves 50 and 56 are actuators controlled by the manual levers 66 and 68 and when the open center type valve in FIG. 2 is in the intermediate or stop position, The discharge is conduits 42 and 48, the central or middle part 50 and 56 of the valve, the auxiliary directional control valve 76 in the open center position, the auxiliary selector valve 78 and the conduit 70 and 72 Return to the storage tank via 74, 44.

The valve 50 is actuated downwardly as shown to allow the lift cylinder (by the valve portion 80) to connect the lift cylinder to the pump via a conduit 42, a check valve 82 and a conduit 84, 52. 46) and the riset 12 by raising the pressure.

Conversely, valve 50 is actuated by conduits 52, 44 and valve portion 86 to connect lift cylinder 46 with the storage tank. Similarly, valve 56 connects the discharge of the pump to the head of the cylinder by conduits 42, 92, 92, check valve 94, valve portion 96 and conduits 58, 62. To operate the cylinder 54 to tilt forward.

The overwrites include valve portions 98 and conduits 60 and 64 of the same circuit upstream as described above, and respective valve portions 96 or 98 and conduits 100 and 74. By means of the opposite end of the cylinder 54, each of which is connected by means of 44, it is inclined backwards by the connection of a pump which discharges to the rod ends of the cylinder 54.

The hydraulic device, except for the combination of the auxiliary selector valve 78 and the auxiliary valve 76, is well known, so that the drawings other than FIG. 9 do not have the lift and the tilting operation and the control device shown, and the present invention. The above mentioned combination or equivalent circuit for adjusting the selector valves 50 and 56 and the lift and tilt cylinders when used in this lift truck is included in the apparatus.

The aids or attachments indicated by the cylinders 30, 32, 34 in FIGS. 2-5 are inoperative or actuated “hold” in the off center position when the valve 76 connects the lines of the storage tank. The other four ports in the central portion of the valve that block the ports, the pair of conduits 102 and 104, the check valve 106 on one side of the valve and the conduit 108 on the other side of the valve. 110).

Since the control valves 76 and 78 have been installed for the above-mentioned purposes, they are conveniently operated at the driver's position on the truck along the control valves 50 and 56 by levers 112 and 114, and the conduits 108 and 110 are connection actuation devices connected to the recess 12 as shown by known devices not shown to operate the independent bifunctional attachment in the illustrated embodiment.

The spring-actuated pilot actuated valve 120 includes the conduit 108 and 110 and the first pair of conduits 122 and 124 connecting the valve portion 126 to the cylinder 34 under certain conditions. 132 is installed in the control circuit between the second pair of conduits 128, 130 connecting the cylinders 30, 32 to the conduits 108, 110 under different conditions.

Shuttle valve 134 has a central pilot port 136 that is connected to valve 120 by a pilot conduit 138 that operates valve 120 under certain conditions such that conduit 108 and 110 can be used. Rather than connecting the cylinder 34 to the coupling, it is connected between the conduits 108 and 110 connecting the cylinders 30 and 32.

Since one of the shuttle valves protrudes through the connecting channel 146, the conduits 108 and 110 containing the high pressure fluid are determined, and the ball checks are alternately changed by the action of the shaft 144. It includes a pair of ball check valves 140 and 142 having a shaft 144 that is protected by actuating opposite ball checks so as not to be fixed.

The hydraulic pressure in the low pressure conduit flowing into the pilot operating chamber of the valve 120 through the unchecked ball check by the channel 146, the pot 136, the pilot conduit 138 and the valve 120 is the spring of FIGS. Usually by 150.

Although the same function can be obtained by installing a shuttle valve in a truck that requires an additional pilot conduit 138 connected to the turnlight, the main circuit structure described above provides only two hydraulic conduits 108 in the turn connection ( It is useful to install the shuttle valve 134 on the attachment or other remote device so that 110 is required.

Although two conduits are used in this embodiment, the use of three such conduits is also within the scope of the present invention.

3 shows the cylinder 34 in the direction shown by the conduit indicated by an arrow through which the pressure fluid flows directly into the cylinder 34 through the portion 126 of the valve 120 by the check valve 106 and the valve portion 152. 2) except that the pilot valve 134 and the valve 120 are connected by actuating the valve 76 and the shuttle valve 134 to the left by the pump discharge pressure in the conduit 108. Same as help The pilot pressure is the storage tank pressure, and while the cylinders 30 and 32 are held in a preselected condition that is dead ported at the valve portion 132, It is connected by conduits 110, 104, 74 via an open port portion 154 of the device selector valve 78 that selects the valve portion 152 that is actuated.

4 shows only that the conditions of FIG. 3 are reversed, and the selector valve 76 is a shuttle valve having no influence on the position of the selector valve 120 and the valve 78 which are the same as those of FIG. Actuated to move the valve portion 156 which reverses the direction of flow of the conduit 108, 110 by actuating 134 to the right, so that FIG. 4 differs from FIG. This is the opposite. 5 shows the conditions for operating the cylinders 30 and 32 to hold the cylinder 34 in a predetermined position.

The valve 76 is identical to the operating position of FIG. 3, but the valve 78 is operated by the driver to the second operating position such that the check valve 160 in the valve portion 162 is operated in the conduit 72.

Check valve 160 is designed to open at 200 psi. The valve 78 is actuated as the valve 76 moves from the position of FIG. 3 to the position of FIG. 5 as shown, and the fluid pressure in the conduits 110, 104, 72 is checked at atmospheric pressure. Increase to 200 psi, the pressure maintained at.

The high pump discharge pressure of conduit 108 keeps shuttle valve 134 in the third and fifth positions, such that conduit 110 pressure causes valve 120 to spring 150 through pilot line 138. ) Actuates the valve portion 132 of 30, 32, and simultaneously locks the cylinder 34 in its current position.

The actuation of the valve 76 to actuate the portion 156 reverses the actuation direction of the cylinders 30 and 32 of FIG. 5 as the shuttle valve 134 acts to the right as in FIG.

Referring again to FIG. 2, the free floating piston head 163 is installed in a small hydraulic cylinder 166 between a pair of opposed springs 164, 165, with the cylinder opposite the line 108. Connected to 110.

During operation, usually, the compensator piston head 163 is not active and moves to one end or the other end of the cylinder as the lines 108 and 110 are pressurized.

However, under special operating conditions that sometimes occur in one or the other cylinders 30, 32, 34, the compensator piston is a small amount of pilot fluid pressure required to operate the valve 120 by the pilot line 138. Supply effectively.

That is, under normal operating conditions, the pilot pressure impulse that actuates the valve 120 is supplied through the shuttle valve by a small motion of the actuator cylinder or cylinders when one side of the actuator piston is released to the storage tank pressure.

However, when the actuator piston is located at the bottom and the end hits one end or the other end of the cylinder, the valve 120 can be operated in the amount necessary to supply the pilot pressure.

In this condition and only in that condition, the compensator piston 163 impulses the pilot line 138 to actuate the valve 120 while the valve 76 changes direction.

Of course, the piston 163 always has the above function, but in order to perform the function, the actuator piston must be located at the bottom. Similar compensator cylinders and connections are shown in the remaining figures.

Of course, by those skilled in the art, a general type hydraulic device can be transformed into a pressure supply pump that supplies the device pressure required for back pressure.

The back pressure of 200 psi is used to select the shift valve 120 and does not affect the operating function of the device represented by the cylinders 30 and 32.

The same is true for this embodiment and all other applications according to the invention.

6, 7, and 8 show a control circuit adapted to operate a three function independent device compared to the two function device of FIGS. 2-5, and also a connection between the main control device and the attachment or other remote control device. Requires only two hydraulic conduits.

As mentioned above, three conduits are used to connect the pilot conduit between the remote device and the relocated shuttle valve, but the maximum benefit occurs when only two conduits are used.

The embodiments of FIGS. 6-8 are similar to the embodiments of FIGS. 2-5, and the same part numbers are indicated identically.

Since the modification to the trifunctional device is as described above, the auxiliary selector valve and the auxiliary control valve, which are indicated at 170, 172, are modified to 78, 120.

Three independent actuators are shown as 171, 173, and 175, alternately connected to a constant port of the multi pored portions 180, 182, 184 of the control valve 172. Respectively connected to the conduits 174, 176, 178, and are installed to perform three independent functions in other devices, such as lift truck attachments or side shifting rotating clamps.

The first and second springs 186 and 188 must be installed as shown in order to move the valve 172 to actuate the pressure fluid to select one of the independent actuators 171, 173 and 175. The spring 186 is preloaded at the illustrated position of the sixth degree valve 172 and the spring 188 holds a retainer plate 189 extending as shown. A slideable spring retainer 187 is preloaded by holding the selected one away from the valve 172.

For example, the valve 172 of FIG. 6 is maintained by storage tank pressure in the preloading spring 186 and pilot line 138 'shown and retainer plate 189 springs (first connected by a valve). Pressure 186 requires 200 psi of valve operating pressure in the pilot line, at which pressure the valve is moved from the position in FIG. 6 to the position in FIG.

In addition, the fluid pressure required to move from the position of FIG. 7 to the position of FIG. 8 by compression of the coupled springs 186, 188 is 400 psi. Known garter springs and glooves, such as not shown in the valve spool and the body, prevent the valve 172 from moving correctly from one position to another. Used for

The control pressure required in the pilot line 138 'is formed by a selector valve device 170 consisting of valve parts 190, 192 and 194, the check belt part 192 being a 200 psi bag in the auxiliary device. It is designed to maintain a back pressure, and the check valve portion 194 is designed to maintain a back pressure of 400 psi.

Between the end springs as shown, which inserts the valve portion 192 downward in the auxiliary circuit, and the valve portion 194 upward in the circuit, the valve 170 usually maintains a normal shape and is not shown. An anti-backlash protector is installed to calibrate valve 170 to the selected position.

The storage tank pressure with the valve section 190 and the directional control valve 76 'shown in the circuit is controlled at the conduit 110' and the pilot line 138 'by the shuttle valve 134' as shown in FIG. So that the control valve 172 is held in the position of FIG. 6 by the spring 186 to connect the first actuating motor or device 171 to the conduit 174. The valve 76 'is held in the position of FIG. 7, the selector valve 170 is operated to fit in the valve portion 192 in the circuit and the pilot line 138 to specifically press the spring 186 as described above. Shuttle valve 134 'is operated to the left as shown in FIG. 6, and the second actuated motor or device 173 is moved to the position of FIG. Is connected to conduit 176 to operate.

In FIG. 8, the control valve 76 'is kept in the same position so that the shuttle valve 134' is left operated while the control valve 170 is operated to insert the valve portion 194 in the circuit. This creates a control pressure of 400 psi in the pilot line 138 'which causes the control valve 172 to press the coupled springs 186 and 188, so that the valve 172 of 400 psi is connected to the conduit 178. Thereby operating to the left end as shown to connect the actuating motor or third device 175 with the valve portion 184.

Of course, the actuation of the directional control valve 76 'to reverse the flow in the auxiliary device is such that the shuttle valve 134' is moved to the right as in FIG. 4, so that the devices 171 (173) (at different control pressure levels) ( 175) It affects each reverse action.

The interlock is designed to connect the selector valve 78 or 170 with the direction control valve lever 112 or 112 'so that the operator can operate the remote device by means of the direction control valve 76 or 76'. As with the use of opposing slots that can control the direction and actuate the levers 112 or 112 'for positioning of the valves 78 or 170 respectively, the driver only needs to position them. To select the remote device actuated by position selection of the selector valve 78 or 170 by manipulation of the lever 112 or 112 '.

However, simultaneous selection operation of two valves is not the scope of the present invention, and the independent lever for operating the two valves in the above-described embodiment has been described.

Although there are several remote auxiliary devices for the auxiliary selector and auxiliary control valve, only two connection conduits such as (108 ') and (110') are needed.

Also the wires connecting the main hydraulic and auxiliary remotes required to move the solenoid valves or to move one remote to another are not required in this embodiment and only hydraulic conduits are required.

9 and 10 are substantial variations of the embodiment described in the above figures.

In FIG. 9, the entire hydraulic system is shown as in FIG. 2, the same parts are shown with the same numerals, and some of the auxiliary control units are removed from FIG. 10 and two primes with the same number as shown in FIGs. (prime) is indicated.

Pump 36 and lift and tilt directional control valves 50 and 56 for operating lift and tilt cylinders 46 and 54 have been described in connection with FIG.

Increasing the control back pressure level formed by the auxiliary selector valve, the auxiliary control valve (valve 172 of FIGS. 6-8 degrees) having a different back pressure level in each flow where the control valve is connected to another actuator; By combining, the principles of the present invention may be used in various device attachments or other devices.

Remote devices 200 and 202 are selected in sequence and direction by actuation of shuttle valve 134 ″ to control the pressure signal for auxiliary control valve 120 ″ via pilot conduit 138 ″. It works.

In this embodiment, the pair of driver direction and remote control selector valves 76 " 204 and the pair of check valve sets 205 < RTI ID = 0.0 > 206 < / RTI > And the driver directional valve and check valve set are one of the valves 76 and 78 of FIG.

Control valves 76 ″ and 204 are located in an intermediate or open center position, and the auxiliary flow is circulated through valves 76 ″ and 204 of the open center portion and the conduit 70 ″ ( 207, 208, 210, and 44 return to the storage tank.

Operating the device 200 in one direction causes the discharge pressure to be sent by the check valve 106 ″, the conduit 102 ″, the valve part 152 ″, the conduit 212, 214 and the valve part 126 ″. Deadports the valve portions of all shown valves 204 to open the operating surface of the device 200, while the valve 204 is held in a central position connecting the valve 76 ″. (76 ″) works downwards.

The flow back from the device 200 to the storage tank is through the valve portion 126 ′, the conduit 216, the valve portion 152 ″ and the conduits 218 (210) 44. Atmospheric pressure flows from the conduit 216 through the shuttle valve 134 " and the pilot line so that the flow discharged from the pump of the conduit 212 by the check valve set 205 and the conduit 220 The control valve 120 " is springed while deadported at the central valve portion of 204, check valve set 205 is connected to conduit 216, and deadported at the central portion of the valve 204 as well. Is held in place to operate the device 200.

Thus, the device 200 is operated in one direction by the operation of the valve 76 ″ and the check valves of the valve sets 205 and 206 are held in place during the operation.

Of course, the reverse actuation of the device 200 also reverses the flow of the conduits 212 and 216, and actuates the reverse actuation of the valve portion 136 "which actuates the shuttle valve 134" to the right. 76 ″).

If the operator operates the device 202, the control valve 76 ″ returns to the center or open-center position and the directional control valve 204 operates the device 202 in one direction or the other.

As shown in FIG. 10, the valve 204 includes a check valve 230, a valve portion 232, a conduit 220, a check valve 234 of the valve set 206, a conduit and a valve portion 132 ″. Through the pump discharge conduit 90 ″ to one side of the device 202.

The return flow from the device 202 is returned to the storage tank through the valve portion 132 ″, the conduit 216, the check valve 236 of the valve set 205, the conduits 238, 240 and 210, The control valve 76 ″ is dead ported in all parts shown.

In check valve sets 205 and 206, checks 234 and 242 allow the conduit to connect the device pressure flow to directly control the pressure flow of the device 202 through the pressure control checks 2 36 and 240. Each is shown as a standard charging check valve having the function of maintaining the pressure in conduits 220 and 238, respectively.

The control pressure checks 236 and 240 are maintained at about 200 psi by spring pressure in the same manner as the check valve 160 of the device selector valve 78 in FIG.

Thus, in the various valves of FIG. 10, the pressure of the flow occurring in the device 202, which is 200 psi above, is controlled by the shuttle valve 134 " and pilot line 138 " Created in conduit 216 by check 236 actuating (120 ″).

In order to reverse the operation of the device 202, the valve 204 is operated to connect the part 250 which reverses the direction of flow in the auxiliary conduit, so that the shuttle valve is operated to the right. The consumed pressure of 202 is controlled to about 200 psi by the check valve 240 holding the control valve 120 "in the illustrated position of FIG.

As described above, the apparatus of FIGS. 9 and 10 can be constructed by the addition of a directional control valve, such as valves 76 ″ and 204, and by the addition of a check valve circuit comprising a set of check valves similar to 205,206. May be modified to operate three or more auxiliary devices, and to operate additional multiported auxiliary control valves for the three auxiliary devices, such as valve 172 in FIGS. All are vertical by the conduits.

For example, as described above in the apparatus according to the embodiments of FIGS. 9 and 10, when the above is applied to a remote device installed in the attachment of the fork truck's turnlight, only a pair of hydraulic conduits connected to the turnlight are shut off. Conduits 214 and 216 between the valve 134 " and the check valves 236 and 240, which are installed in the truck.

Also, if a shuttle valve is installed in the truck, a third line, pilot line 138 ″, must be connected to the overflow, but in this embodiment no remote solenoid valve or the like is connected to operate the remote hydraulics. Only two connected hydraulic conduits are needed.

The above embodiments do not limit the scope of the present invention, and various modifications may be made by those skilled in the art, but the scope of the present invention may not be exceeded.

This summary of the invention is as follows.

The coupling of the valve unit is installed to operate two or more hydraulic units, and as such the valve unit is as described above, at least to connect the main hydraulic unit and the remote unit from the lift truck to the attachment support carriage of the lift truck stand. It is a hydraulic control circuit used for multifunctional hydraulic devices such as industrial lift truck attachments that require hydraulic conduits and do not require wires to connect switching devices between hydraulic devices such as solenoid operated valves.

Claims (1)

To the first and second control pressures of the system, the low pressure section of the system for connecting the valve unit in the first position to the first hydraulic motor unit and the valve unit in the second position to the second hydraulic motor unit. In the first and second hydraulic motor device, selector valve device, which is able to move to the first and second positions accordingly, select the operation of the first or second hydraulic motor (30) (34), Or a shuttle valve device 134 that continuously reacts to the high pressure part of the system such that the low pressure part of the collector valve device 120 is continuously connected when the driver valve device 76 and the system suitable for forming the second control pressure are in operation. Hydraulic control device for operating a multi-function remote device with a minimum connection conduit characterized in that consisting of.

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