TW201425740A - Hydraulic circuit and loading and unloading vehicle - Google Patents
Hydraulic circuit and loading and unloading vehicle Download PDFInfo
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- TW201425740A TW201425740A TW102144513A TW102144513A TW201425740A TW 201425740 A TW201425740 A TW 201425740A TW 102144513 A TW102144513 A TW 102144513A TW 102144513 A TW102144513 A TW 102144513A TW 201425740 A TW201425740 A TW 201425740A
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
- B62D5/065—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle characterised by specially adapted means for varying pressurised fluid supply based on need, e.g. on-demand, variable assist
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
- B62D—MOTOR VEHICLES; TRAILERS
- B62D5/00—Power-assisted or power-driven steering
- B62D5/06—Power-assisted or power-driven steering fluid, i.e. using a pressurised fluid for most or all the force required for steering a vehicle
- B62D5/07—Supply of pressurised fluid for steering also supplying other consumers ; control thereof
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
- B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
- B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
- B66F9/075—Constructional features or details
- B66F9/20—Means for actuating or controlling masts, platforms, or forks
- B66F9/22—Hydraulic devices or systems
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/16—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors
- F15B11/17—Servomotor systems without provision for follow-up action; Circuits therefor with two or more servomotors using two or more pumps
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
- F15B2211/205—Systems with pumps
- F15B2211/20576—Systems with pumps with multiple pumps
- F15B2211/20584—Combinations of pumps with high and low capacity
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/405—Flow control characterised by the type of flow control means or valve
- F15B2211/40523—Flow control characterised by the type of flow control means or valve with flow dividers
- F15B2211/4053—Flow control characterised by the type of flow control means or valve with flow dividers using valves
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/41—Flow control characterised by the positions of the valve element
- F15B2211/411—Flow control characterised by the positions of the valve element the positions being discrete
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/40—Flow control
- F15B2211/415—Flow control characterised by the connections of the flow control means in the circuit
- F15B2211/41509—Flow control characterised by the connections of the flow control means in the circuit being connected to a pressure source and a directional control valve
- F15B2211/41518—Flow control characterised by the connections of the flow control means in the circuit being connected to a pressure source and a directional control valve being connected to multiple pressure sources
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B2211/00—Circuits for servomotor systems
- F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
- F15B2211/78—Control of multiple output members
- F15B2211/781—Control of multiple output members one or more output members having priority
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- Engineering & Computer Science (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Combustion & Propulsion (AREA)
- Structural Engineering (AREA)
- Fluid Mechanics (AREA)
- General Engineering & Computer Science (AREA)
- Civil Engineering (AREA)
- Physics & Mathematics (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Fluid-Pressure Circuits (AREA)
- Forklifts And Lifting Vehicles (AREA)
Abstract
Description
本發明主要是有關於一種包括裝卸裝置的堆高機 (forklift)等產業車輛、尤其是裝卸車輛中所使用的液壓迴路、以及包括此種液壓迴路的裝卸車輛。 The invention mainly relates to a stacker including a loading and unloading device Industrial vehicles such as forklifts, particularly hydraulic circuits used in loading and unloading vehicles, and loading and unloading vehicles including such hydraulic circuits.
以往，於包括裝卸裝置的堆高機等產業車輛、尤其是裝 卸車輛中，廣泛使用著液壓迴路a1，如圖4所示，該液壓迴路a1包括：作為液壓供給源的液壓泵(pump)a2；分流閥a4，其用以將來自液壓泵a2的作動液優先供給至轉向機構(steering)a5，並且將剩餘的作動液供給至裝卸用致動器(actuator)a8；流量調整閥a6，其設置於該分流閥a4與裝卸用致動器a8之間；及通路a9，其自用以儲存作動液的槽(tank)a7經由上述液壓泵a2、上述分流閥a4及上述流量調整閥a6連接至上述裝卸用致動器a8。 In the past, industrial vehicles such as stackers including loading and unloading devices, especially In the unloading vehicle, the hydraulic circuit a1 is widely used. As shown in FIG. 4, the hydraulic circuit a1 includes a hydraulic pump a2 as a hydraulic supply source, and a diverter valve a4 for operating the hydraulic fluid from the hydraulic pump a2. It is preferentially supplied to the steering mechanism a5, and the remaining operating fluid is supplied to the loading and unloading actuator (a8); the flow regulating valve a6 is disposed between the diverter valve a4 and the loading and unloading actuator a8; The passage a9 is connected to the loading/unloading actuator a8 via a hydraulic pump a2, the diverter valve a4, and the flow rate adjusting valve a6 from a tank a7 for storing an operating fluid.
此外，來自液壓泵的作動液的流量與液壓泵的轉速成比 例。此外，於未進行裝卸操作時，剩餘的作動液經由流量調整閥返回至槽中。此時，於使用僅具有1個液壓泵的液壓迴路時，如 圖5所示，自泵噴出的作動液的全部量於被供給至轉向機構的液壓下於分流閥a4內流通。即，於未進行裝卸操作時，相當於圖5的斜線所示的區域的量的作動液不必要地於分流閥a4內流通，伴隨壓力損耗而產生的動力損耗變大。即，能量(energy)的浪費變大。 In addition, the flow rate of the hydraulic fluid from the hydraulic pump is proportional to the rotational speed of the hydraulic pump example. Further, when the loading and unloading operation is not performed, the remaining operating fluid is returned to the tank via the flow rate adjusting valve. At this time, when using a hydraulic circuit with only one hydraulic pump, such as As shown in Fig. 5, the entire amount of the hydraulic fluid discharged from the pump flows through the diverter valve a4 under the hydraulic pressure supplied to the steering mechanism. In other words, when the detachment operation is not performed, the amount of the actuator corresponding to the area indicated by the oblique line in FIG. 5 is unnecessarily distributed in the diverter valve a4, and the power loss due to the pressure loss is increased. That is, the waste of energy becomes large.
作為用以減少此種浪費的構成，考慮有液壓迴路b1，具 有多個液壓泵，例如，如圖6所示，具有第1液壓泵b2及第2液壓泵b3，且具有如下構成。該液壓迴路b1包括：作為液壓供給源的上述第1液壓泵b2及第2液壓泵b3；分流閥b4，其用以將來自該等液壓泵b2、b3的作動液優先供給至轉向機構b5，並且將剩餘的作動液供給至裝卸用致動器b8；流量調整閥b6，其設置於該分流閥b4與裝卸用致動器b8之間；主通路b9，其自用以儲存作動液的槽b7經由上述第1液壓泵b2、上述分流閥b4及上述流量調整閥b6連接至上述裝卸用致動器b8；及副通路b10，其自上述主通路b9的上述槽b7與上述第1液壓泵b2之間分支，並經由上述第2液壓泵b3於上述分流閥b4與上述流量調整閥b6之間再次匯合於主通路b9。此種液壓迴路b1中，以於第1及第2液壓泵b2、b3以最低轉數nmin旋轉時可對轉向機構b5供給所需的最低限度量的作動液的方式，設定第1液壓泵b2的容量，與前文所述的構成者相比，可削減通過分流閥b4內的液量。 As a configuration for reducing such waste, a hydraulic circuit b1 is considered, and a plurality of hydraulic pumps are provided. For example, as shown in FIG. 6, the first hydraulic pump b2 and the second hydraulic pump b3 are provided, and have the following configuration. The hydraulic circuit b1 includes the first hydraulic pump b2 and the second hydraulic pump b3 as hydraulic supply sources, and a diverter valve b4 for preferentially supplying the hydraulic fluid from the hydraulic pumps b2 and b3 to the steering mechanism b5. And the remaining operating fluid is supplied to the loading and unloading actuator b8; the flow regulating valve b6 is disposed between the diverter valve b4 and the loading and unloading actuator b8; and the main passage b9 is used for the tank b7 for storing the actuating liquid. The first hydraulic pump b2, the flow dividing valve b4, and the flow rate adjusting valve b6 are connected to the attaching and detaching actuator b8, and the auxiliary passage b10 is formed from the groove b7 of the main passage b9 and the first hydraulic pump b2. The branching branch is again merged with the main passage b9 between the diverter valve b4 and the flow rate adjusting valve b6 via the second hydraulic pump b3. In the hydraulic circuit b1, when the first and second hydraulic pumps b2 and b3 are rotated at the minimum number of revolutions nmin , the first hydraulic pump can be set to supply the required minimum amount of the operating fluid to the steering mechanism b5. The capacity of b2 can reduce the amount of liquid passing through the diverter valve b4 as compared with the above-described constituents.
然而，即便是此種構成，於轉速高時，自上述第1液壓 泵b2噴出並通過分流閥b4的作動液的量大，於未進行上述裝卸操作時，相當於圖5的斜線所示的區域的量的作動液不必要地於分流閥b4內流通，伴隨壓力損耗而產生的動力損耗依然大，能量 的浪費變大。 However, even in such a configuration, the first hydraulic pressure is from the above first hydraulic pressure when the rotational speed is high. The amount of the hydraulic fluid discharged from the pump b2 and passing through the flow dividing valve b4 is large. When the above-described loading and unloading operation is not performed, the amount of the operating fluid corresponding to the area indicated by the oblique line in Fig. 5 is unnecessarily distributed in the diverter valve b4. Power loss due to loss is still large, energy The waste is getting bigger.
背景技術文獻Background art literature
專利文獻Patent literature
專利文獻1：日本專利特開2010-76937號公報 Patent Document 1: Japanese Patent Laid-Open Publication No. 2010-76937
本發明著眼於以上方面，其目的在於：於包括裝卸裝置的堆高機等產業車輛、尤其是裝卸車輛中所使用的液壓迴路中，實現未進行裝卸作業時伴隨壓力損耗而產生的動力損耗之大幅削減。 The present invention has been made in view of the above points, and an object thereof is to realize power loss caused by pressure loss during unloading operations in an industrial vehicle such as a stacker including a loading and unloading device, particularly a hydraulic circuit used in a loading and unloading vehicle. Significant cuts.
為了解決以上課題，本發明的液壓迴路具有如下所述的構成。即，本發明的液壓迴路包括：多個液壓泵，作為液壓供給源；分流閥，用以將來自該等液壓泵的作動液優先供給至轉向機構，並且將剩餘的作動液供給至裝卸用致動器；及流量調整閥，設置於該分流閥與裝卸用致動器之間；且該液壓迴路具有1個主泵(main pump)及至少1個副泵(sub pump)作為上述多個液壓泵，進而包括切換閥，該切換閥設置於上述副泵與分流閥之間，且於上述主泵的噴出流量小於規定噴出流量，或上述主泵的轉速小於規定轉速時，採取第1狀態，將來自上述副泵的作動液導引至分流閥的上游側，並且，於上述主泵的噴出流量大於規定噴出流量，或上述主泵的轉速大於規定轉速時，採取第2狀態，將來自上述副泵的作動液導引至在分流閥的下游側及在流量調整閥的 上游側進行匯合的旁通(bypass)通路。 In order to solve the above problems, the hydraulic circuit of the present invention has the following configuration. That is, the hydraulic circuit of the present invention includes: a plurality of hydraulic pumps as a hydraulic supply source; a diverter valve for preferentially supplying the operating fluid from the hydraulic pumps to the steering mechanism, and supplying the remaining operating fluid to the loading and unloading And a flow regulating valve disposed between the diverter valve and the loading and unloading actuator; and the hydraulic circuit has a main pump and at least one sub pump as the plurality of hydraulic pumps The pump further includes a switching valve that is disposed between the sub-pump and the diverter valve, and adopts a first state when the discharge flow rate of the main pump is less than a predetermined discharge flow rate or when the rotation speed of the main pump is less than a predetermined rotation speed. Leading the operating fluid from the sub-pump to the upstream side of the diverter valve, and taking the second state when the discharge flow rate of the main pump is greater than a predetermined discharge flow rate or when the rotation speed of the main pump is greater than a predetermined rotation speed The auxiliary pump's operating fluid is directed to the downstream side of the diverter valve and to the flow regulating valve The upstream side performs a bypass bypass path.
此外，為了解決上述課題，本發明的裝卸車輛包括上段所述的液壓迴路。 Further, in order to solve the above problems, the loading and unloading vehicle of the present invention includes the hydraulic circuit described in the above paragraph.
若為此種構成，則將僅利用來自上述主泵的作動液便可確保轉向機構所需的作動液的規定流量之主泵的轉速設定為上述規定轉速，且於上述主泵的噴出流量小於規定噴出流量，或上述主泵的轉速小於規定轉速時，將切換閥設為第1狀態，藉此即便減小未連接於上述旁通通路的液壓泵即上述主泵的容量，亦可確保供給至轉向機構的作動液的流量。另一方面，由於可減小上述主泵的容量，因此，於未進行裝卸操作且液壓泵的轉速較高時將切換閥設為第2狀態，藉此與以往相比可大幅地削減通過分流閥的作動液的量，故可實現未進行裝卸作業時伴隨壓力損耗而產生的動力損耗之大幅削減。 According to this configuration, the number of revolutions of the main pump that ensures the predetermined flow rate of the operating fluid required for the steering mechanism can be set to the predetermined number of revolutions only by the operating fluid from the main pump, and the discharge flow rate of the main pump is smaller than When the discharge flow rate is specified or the rotation speed of the main pump is less than the predetermined rotation speed, the switching valve is set to the first state, and the supply of the main pump can be ensured even if the hydraulic pump that is not connected to the bypass passage is reduced. The flow rate of the actuation fluid to the steering mechanism. On the other hand, since the capacity of the main pump can be reduced, when the detachment operation is not performed and the rotation speed of the hydraulic pump is high, the switching valve is set to the second state, whereby the bypass can be greatly reduced as compared with the related art. Since the amount of the operating fluid of the valve is reduced, the power loss caused by the pressure loss during the unloading operation can be greatly reduced.
根據本發明，可於包括裝卸裝置的堆高機等產業車輛、尤其是裝卸車輛中所使用的液壓迴路中，實現未進行裝卸作業時伴隨壓力損耗而產生的動力損耗之大幅削減。 According to the present invention, it is possible to achieve a significant reduction in power loss due to pressure loss during unloading operations in an industrial vehicle such as a stacker including a loading and unloading device, particularly a hydraulic circuit used in a loading and unloading vehicle.
1、a1、b1‧‧‧液壓迴路 1, a1, b1‧‧‧ hydraulic circuit
2‧‧‧主泵(液壓泵) 2‧‧‧Main pump (hydraulic pump)
3‧‧‧副泵(液壓泵) 3‧‧‧Sub pump (hydraulic pump)
4、a4、b4‧‧‧分流閥 4, a4, b4‧‧‧ diverter valve
4a‧‧‧輸入端口 4a‧‧‧Input port
4b‧‧‧剩餘流輸出口 4b‧‧‧Remaining flow output
4c‧‧‧優先流輸出口 4c‧‧‧Priority flow output
5、a5、b5‧‧‧轉向機構 5, a5, b5‧‧‧ steering mechanism
6、a6、b6‧‧‧流量調整閥 6, a6, b6‧‧‧ flow adjustment valve
7、a7、b7‧‧‧槽 7, a7, b7‧‧‧ slot
8、a8、b8‧‧‧裝卸用致動器 8, a8, b8‧‧‧ loading and unloading actuator
9、b9‧‧‧主通路 9, b9‧‧‧ main pathway
10‧‧‧第1副通路 10‧‧‧1st secondary access
11‧‧‧旁通通路(第2副通路) 11‧‧‧ bypass path (second secondary path)
12、13‧‧‧切換閥 12, 13‧‧‧Switching valve
12a、13a‧‧‧盤簧 12a, 13a‧‧‧ coil spring
12b、13b‧‧‧螺線管 12b, 13b‧‧‧ Solenoid
14‧‧‧槽通路 14‧‧‧ slot access
a2‧‧‧液壓泵 A2‧‧‧ hydraulic pump
a9‧‧‧通路 A9‧‧‧ pathway
b2‧‧‧第1液壓泵 B2‧‧‧1st hydraulic pump
b3‧‧‧第2液壓泵 B3‧‧‧2nd hydraulic pump
b10‧‧‧副通路 B10‧‧‧Sub-pathway
圖1是表示本發明的一實施形態的液壓迴路的迴路圖。 Fig. 1 is a circuit diagram showing a hydraulic circuit according to an embodiment of the present invention.
圖2是表示上述實施形態的液壓泵的轉速與通過液壓迴路的分流閥的作動液的流量的關係的圖。 Fig. 2 is a view showing the relationship between the number of revolutions of the hydraulic pump of the above embodiment and the flow rate of the operating fluid passing through the diverter valve of the hydraulic circuit.
圖3是表示本發明的另一實施形態的液壓迴路的迴路圖。 Fig. 3 is a circuit diagram showing a hydraulic circuit according to another embodiment of the present invention.
圖4是表示現有的液壓迴路的迴路圖。 4 is a circuit diagram showing a conventional hydraulic circuit.
圖5是表示圖4所示的液壓迴路中的液壓泵的轉速與通過液壓迴路的分流閥的作動液的流量的關係的圖。 Fig. 5 is a graph showing the relationship between the number of revolutions of the hydraulic pump in the hydraulic circuit shown in Fig. 4 and the flow rate of the operating fluid passing through the diverter valve of the hydraulic circuit.
圖6是表示現有的液壓迴路的迴路圖。 Fig. 6 is a circuit diagram showing a conventional hydraulic circuit.
圖7是表示圖6所示的液壓迴路中的液壓泵的轉速與通過液壓迴路的分流閥的作動液的流量的關係的圖。 Fig. 7 is a view showing the relationship between the number of revolutions of the hydraulic pump in the hydraulic circuit shown in Fig. 6 and the flow rate of the operating fluid passing through the diverter valve of the hydraulic circuit.
一面參照圖1及圖2一面將本發明的一實施形態示於以下。 An embodiment of the present invention will be described below with reference to Figs. 1 and 2 .
本實施形態的液壓迴路1是搭載於裝卸車輛的迴路，如圖1所示，包括：作為液壓供給源的兩個液壓泵、即主泵2及副泵3；分流閥4，其用以將來自該等液壓泵即主泵2及副泵3的作動液優先供給至轉向機構5，並且將剩餘的作動液供給至裝卸用致動器8；流量調整閥6，其設置於該分流閥4與裝卸用致動器8之間；主通路9，其自用以儲存作動液的槽7經由上述主泵2、上述分流閥4及上述流量調整閥6連接至上述裝卸用致動器8；第1副通路10，其自上述主通路9的上述槽7與上述主泵2之間分支，並經由上述副泵3於上述主通路9的上述主泵2與上述分流閥4之間再次匯合於主通路9；第2副通路11，其自上述第1副通路10的上述副泵3與分流閥4之間分支，並於上述主通路9的上述分流閥4與上述流量調整閥6之間匯合於上述主通路9；及切換閥12，其設置於上述第2副通路11與上述第1副通路10分支的位置，且於主泵2的轉速小於規定轉速n1時，採取第1狀態，將來 自上述副泵3的作動液導引至分流閥4的上游側，並且，於主泵2的轉速大於規定轉速n1時，採取第2狀態，將來自上述副泵3的作動液導引至上述第2副通路11。此處，上述第2副通路11是申請專利範圍中的旁通通路。 The hydraulic circuit 1 of the present embodiment is a circuit mounted on a loading and unloading vehicle. As shown in Fig. 1, the hydraulic circuit 1 includes two hydraulic pumps as a hydraulic supply source, that is, a main pump 2 and a sub-pump 3, and a diverter valve 4 for The operating fluids from the hydraulic pumps, that is, the main pump 2 and the sub-pump 3, are preferentially supplied to the steering mechanism 5, and the remaining operating fluid is supplied to the loading and unloading actuator 8, and the flow regulating valve 6 is provided to the diverter valve 4. Between the loading and unloading actuators 8; the main passage 9 is connected to the loading and unloading actuator 8 via the main pump 2, the diverter valve 4, and the flow rate adjusting valve 6 through a tank 7 for storing an operating fluid; a sub passage 10 branched from the groove 7 of the main passage 9 and the main pump 2, and again merged between the main pump 2 of the main passage 9 and the diverter valve 4 via the sub-pump 3 a main passage 9; a second sub-passage 11 branched between the sub-pump 3 and the diverter valve 4 of the first sub-passage 10, and between the diverter valve 4 of the main passage 9 and the flow rate adjusting valve 6 Converging in the main passage 9; and the switching valve 12 provided in the second sub passage 11 and the first sub passage 10 branched position and the rotational speed of the main pump 2 is smaller than the predetermined rotational speed n is 1, taking a first state, from the actuating fluid guide said secondary pump 3 to the diverter valve upstream side 4 and, in the main pump 2 When the number of revolutions is greater than the predetermined number of revolutions n 1 , the second state is adopted, and the operating fluid from the sub-pump 3 is guided to the second sub-passage 11 . Here, the second sub-passage 11 is a bypass passage in the scope of the patent application.
上述主泵2及副泵3均連接於未圖示的作為動力源的車 輛驅動用發動機(engine)或馬達(motor)，為以相同轉速進行連動旋轉的周知構成的固定容量泵。此處，該等主泵2及副泵3的轉速處於最低轉速nmin與最高轉速nmax之間。 Each of the main pump 2 and the sub-pump 3 is connected to a vehicle driving engine or a motor (not shown) as a power source, and is a fixed-capacity pump of a known configuration that rotates at the same number of revolutions. Here, the rotational speeds of the main pump 2 and the sub-pump 3 are between the minimum rotational speed nmin and the highest rotational speed nmax .
上述分流閥4具有與作為堆高機等中所使用的對轉向機 構5、及裝卸用致動器8供給作動液的優先閥機構而周知者相同的構成。即，該分流閥4包括：輸入端口4a，其作為自上述主泵2及副泵3噴出的高壓作動液的導入口；優先流輸出口4b，其將轉向機構5的作動所需的作動液優先朝向轉向機構5噴出；及剩餘流輸出口4c，其將剩餘的作動液朝向裝卸用致動器8噴出。自上述剩餘流輸出口4c噴出的作動液經由上述流量調整閥6被導引至裝卸用致動器8。 The above-mentioned diverter valve 4 has a pair of steering gears used as a stacker or the like The structure 5 and the attaching and detaching actuator 8 supply the priority valve mechanism of the operating fluid, and the same configuration is known. That is, the diverter valve 4 includes an input port 4a as an inlet port for the high-pressure actuating liquid discharged from the main pump 2 and the sub-pump 3, and a preferential flow output port 4b for the actuating liquid required for the operation of the steering mechanism 5. The discharge mechanism 5 is preferentially discharged, and the remaining flow output port 4c discharges the remaining operating fluid toward the attaching and detaching actuator 8. The operating fluid discharged from the remaining flow output port 4c is guided to the attaching and detaching actuator 8 via the flow rate adjusting valve 6.
上述流量調整閥6具有如下功能：接受未圖示的操作桿 (lever)所受到的操作而變更開度，藉此調整被導引至裝卸用致動器8的作動液的量。 The flow rate adjusting valve 6 has a function of accepting an operating lever (not shown) The opening degree is changed by the operation received, thereby adjusting the amount of the operating fluid guided to the attaching and detaching actuator 8.
並且，上述切換閥12如上所述般設置於上述副泵3與 分流閥4之間，於主泵2的轉速小於規定旋轉速n1時，即，來自主泵2的噴出流量小於為了使轉向機構5作動所需的最低限度的流量即規定噴出流量fmin時，採取第1狀態，將來自上述副泵3的作動液經由第1副通路10導引至分流閥4的上游側，於主泵2 的轉速大於規定轉速n1時，採取第2狀態，將來自上述副泵3的作動液經由第2副通路11導引至分流閥4的下游側且流量調整閥6的上游側。此處，來自主泵2的作動液的噴出流量與主泵2的轉速大致成比例。即，於上述規定轉速n1時，自主泵2噴出的作動液的流量與上述規定噴出流量fmin大致相等。並且，該切換閥12內置有：盤簧(coil spring)12a，其作為用於賦能以採取第1狀態的賦能構件；及螺線管(solenoid)12b，其用以於供電時對抗上述盤簧12a的賦能力而採取第2狀態，該螺線管12b連接於下述未圖示的控制裝置。該控制裝置是將包括中央處理單元(Central Processing Unit，CPU)、記憶裝置、輸入輸出界面(interface)的微電腦系統(microcomputer system)、與檢測發動機或馬達的轉速的轉數感測器(sensor)連接而形成者，於上述轉數感測器的輸出信號所表示的轉速大於上述規定轉速n1時，進行對上述螺線管12b通電而使切換閥12為第2狀態的控制。 Further, as described above, the switching valve 12 is provided between the sub-pump 3 and the diverter valve 4, the rotational speed of the main pump 2 is smaller than the predetermined rotational speed n 1, i.e., the discharge flow rate from the main pump 2 is smaller than for the steering minimum mechanism 5 actuated the desired flow rate that is predetermined when the discharge flow rate f min, to take a first state, from the sub-pump actuating fluid 3 via the first upstream sub-passage 10 directed to the diverter valve 4 side of the main When the number of revolutions of the pump 2 is greater than the predetermined number of revolutions n 1 , the second state is adopted, and the operating fluid from the sub-pump 3 is guided to the downstream side of the diverter valve 4 via the second sub-passage 11 and upstream of the flow rate adjusting valve 6 . Here, the discharge flow rate of the operating fluid from the main pump 2 is substantially proportional to the rotation speed of the main pump 2. That is, the rotation speed n 1, the flow rate of the liquid independent actuation of the pump discharge flow rate 2 f min discharged substantially equal to the predetermined specified above. Further, the switching valve 12 includes a coil spring 12a as an energizing member for energizing to take the first state, and a solenoid 12b for opposing the above when supplying power. The second state is adopted in the energization of the coil spring 12a, and the solenoid 12b is connected to a control device (not shown). The control device is a microcomputer system including a central processing unit (CPU), a memory device, an input/output interface, and a sensor for detecting the rotational speed of the engine or the motor. When the connection is formed, when the number of revolutions indicated by the output signal of the number-of-revolution sensor is greater than the predetermined number of revolutions n 1 , the solenoid 12b is energized to control the switching valve 12 to the second state.
此處，若一面參照圖2一面對主泵2的轉速與通過分流 閥4的流量的關係進行敍述，則於轉速小於上述規定轉速n1時，如上所述般，切換閥12採取第1狀態，因此，自主泵2及副泵3噴出的作動液均通過分流閥4。因此，通過分流閥4的流量成為如圖2的實線D1+D2所示者。另一方面，於轉速大於上述規定轉速n1時，如上所述般，切換閥12採取第2狀態，因此，僅自主泵2噴出的作動液通過分流閥4。因此，通過分流閥4的流量成為如圖2的虛線D1所示者。此時，自主泵2噴出的作動液的流量大於為了使轉向機構5作動所需的最低限度的流量即上述規定噴出流量fmin。 Here, if the face of the rotational speed of the main pump 2 will be described by the relationship between the flow diverter valve 4 with reference to FIG. 2 a side, the rotational speed is less than the predetermined rotational speed when n 1 is, as described above, the switching valve 12 to take a first In this state, the actuating liquid discharged from the main pump 2 and the sub-pump 3 passes through the diverter valve 4. Therefore, the flow rate through the diverter valve 4 is as shown by the solid line D1+D2 of FIG. 2 . 1 On the other hand, the rotational speed is greater than the predetermined rotational speed n, as described above, the switching valve 12 to take the second state, therefore, only the two independent pump actuated fluid discharged by the shunt valve 4. Therefore, the flow rate through the diverter valve 4 becomes as shown by a broken line D1 in Fig. 2 . At this time, the flow rate of the hydraulic fluid discharged from the main pump 2 is larger than the minimum discharge flow rate required to operate the steering mechanism 5, that is, the predetermined discharge flow rate fmin .
即，根據本實施形態，與參照圖4及圖5所說明的僅利用1個液壓泵a2的現有的液壓迴路a1相比，於轉數高的區域中，可大幅地削減通過分流閥4的作動液的流量。更具體而言，於未進行裝卸操作時，於分流閥4中不必要地流通的作動液的量是相當於圖2的斜線所示的區域的量，於轉速大於上述規定轉速n1的區域，即自主泵2噴出的作動液的流量大於上述規定噴出流量fmin的區域中，可將於分流閥4中不必要地流通的作動液的量削減掉和圖2中上述圖2的實線D1+D2的延長部分與上述虛線D1之間的區域X相當的量。此外，即便與參照圖6及圖7所說明的現有的液壓迴路1相比，亦由於在最低轉數nmin附近時利用主泵2及副泵3，因此，無需僅由來自主泵2的作動液確保為了使轉向機構5作動所需的最低限度的流量fmin，可減小主泵2的容量，因此，可於轉數高的區域中大幅地削減通過分流閥4的作動液的流量。即，與現有的液壓迴路1相比，可藉由大幅地削減通過分流閥4的作動液的流量而抑制伴隨作動液通過分流閥4的壓力損耗而產生的動力損耗。並且，亦可大幅地削減因該動力損耗所導致的能量的浪費。 In other words, according to the present embodiment, compared with the conventional hydraulic circuit a1 using only one hydraulic pump a2 described with reference to Figs. 4 and 5, the passage through the diverter valve 4 can be greatly reduced in the region where the number of revolutions is high. Actuating fluid flow. More specifically, when the loading and unloading operation is not performed, the amount of the operating fluid that is unnecessarily distributed in the diverter valve 4 is the amount corresponding to the area indicated by the oblique line in FIG. 2, and the area where the rotational speed is greater than the predetermined rotational speed n 1 regional flow actuating fluid discharged, i.e. independent of the pump is greater than the predetermined discharge flow rate f min, the can will diverter valve 4, the amount of actuating fluid unnecessarily flow cut off and the solid line in the drawing in FIG. 2. 2 The amount of the extension of D1+D2 is equivalent to the area X between the above-mentioned broken line D1. Further, even when compared with the conventional hydraulic circuit 1 described with reference to FIGS. 6 and 7, since the main pump 2 and the sub-pump 3 are used in the vicinity of the minimum number of revolutions n min , it is not necessary to be operated only by the main pump 2 . The liquid ensures that the capacity of the main pump 2 can be reduced in order to minimize the flow rate f min required for the steering mechanism 5 to operate. Therefore, the flow rate of the operating fluid passing through the diverter valve 4 can be greatly reduced in the region where the number of revolutions is high. In other words, the power loss caused by the pressure loss of the actuating liquid passing through the diverter valve 4 can be suppressed by substantially reducing the flow rate of the operating fluid passing through the diverter valve 4 as compared with the conventional hydraulic circuit 1. Moreover, the waste of energy due to the power loss can be greatly reduced.
另外，本發明不限於上述實施例。 Further, the present invention is not limited to the above embodiment.
例如，亦可如圖3所示，於旁通通路即第2副流路11中設置第2切換閥13，該第2切換閥13可採取將通過副泵3的作動液經由槽通路14導引至槽7的第1狀態、及將通過副泵3的作動液導引至流量調整閥6的上游側的第2狀態。該第2切換閥13內置有：盤簧13a，其作為用於賦能以採取第1狀態的賦能構件；及螺線管13b，其用以於供電時對抗上述盤簧13a的賦能力而採取 第2狀態；該螺線管連接於下述控制裝置。該控制裝置是將包括CPU、記憶裝置、輸入輸出界面的微電腦系統、與檢測發動機或馬達的轉速的未圖示的轉數感測器連接而形成者，於未進行裝卸作業時，進行對上述螺線管13b通電而使切換閥13為第2狀態的控制。另外，圖3所示的液壓迴路1於其他方面具有與圖1及圖2所示的液壓迴路1相同的構成，因此，對於對應的部位標附相同的名稱及符號，省略詳細的說明。 For example, as shown in FIG. 3, a second switching valve 13 may be provided in the second sub-flow path 11 which is a bypass passage, and the second switching valve 13 may take the actuation fluid passing through the sub-pump 3 through the groove passage 14. The first state led to the tank 7 and the second state in which the operating fluid passing through the sub-pump 3 is guided to the upstream side of the flow rate adjusting valve 6. The second switching valve 13 includes a coil spring 13a as an energizing member for energizing to take the first state, and a solenoid 13b for resisting the energizing force of the coil spring 13a during power supply. take The second state; the solenoid is connected to the control device described below. The control device is formed by connecting a microcomputer system including a CPU, a memory device, and an input/output interface to a number-of-revolution sensor (not shown) that detects the number of revolutions of the engine or the motor, and performs the above-described operation when the loading/unloading operation is not performed. The solenoid 13b is energized to cause the switching valve 13 to be in the second state. In addition, the hydraulic circuit 1 shown in FIG. 3 has the same configuration as the hydraulic circuit 1 shown in FIG. 1 and FIG. 2, and the same reference numerals and signs are attached to the corresponding parts, and detailed description is omitted.
若為此種構成，則於未進行裝卸作業時，可在無負荷條 件下將通過副泵3的作動液導引至槽7，因此，亦可抑制伴隨作動液通過流量調整閥6的壓力損耗而產生的動力損耗。並且，可進一步削減該動力損耗所導致的能量浪費。 If it is such a configuration, it can be in the no-load bar when the loading and unloading operation is not performed. The pilot liquid is guided to the tank 7 by the actuating liquid of the sub-pump 3, so that the power loss caused by the pressure loss of the actuating fluid passing through the flow rate adjusting valve 6 can be suppressed. Moreover, the waste of energy caused by the power loss can be further reduced.
此外，亦可將本發明應用於具有多個副泵的液壓迴路。 Furthermore, the invention can also be applied to a hydraulic circuit having a plurality of secondary pumps.
此外，上述實施形態中，著眼於利用固定容量泵作為主泵及副泵，且轉速與噴出流量大致成比例的情況，而於轉速小於規定轉速時，使切換閥採取將來自上述副泵的作動液導引至分流閥的上游側的第1狀態，並且於轉速大於規定轉速時，使切換閥採取將來自上述副泵的作動液導引至旁通通路的第2狀態，但亦可採用如下構成：使用流量感測器等流量檢測元件直接檢測來自主泵的作動液的噴出流量，於檢測到的作動液的噴出流量小於規定噴出流量時，使切換閥採取將來自上述副泵的作動液導引至分流閥的上游側的第1狀態，並且於檢測到的作動液的噴出流量大於規定噴出流量時，使切換閥採取將來自上述副泵的作動液導引至旁通通路的第2狀態。 Further, in the above-described embodiment, attention is paid to the case where the fixed displacement pump is used as the main pump and the sub-pump, and the number of revolutions is approximately proportional to the discharge flow rate, and when the number of revolutions is less than the predetermined number of revolutions, the switching valve is actuated by the slave pump. The liquid is guided to the first state on the upstream side of the diverter valve, and when the number of revolutions is greater than the predetermined number of revolutions, the switching valve is caused to take the second state in which the actuating liquid from the sub-pump is guided to the bypass passage, but the following may be employed The flow rate detecting element such as a flow sensor directly detects the discharge flow rate of the actuation liquid from the main pump, and when the detected discharge flow rate of the actuation liquid is smaller than the predetermined discharge flow rate, causes the switching valve to take the actuation fluid from the auxiliary pump. Guided to the first state on the upstream side of the diverter valve, and when the detected discharge flow rate of the actuating liquid is greater than the predetermined discharge flow rate, the switching valve is caused to take the second to guide the actuating liquid from the sub-pump to the bypass passage status.
此外，亦可於不損害本發明的主旨的範圍內進行各種變 更。 Further, various changes can be made without departing from the gist of the present invention. more.
若採用本發明的構成，則可於包括裝卸裝置的堆高機等產業車輛、尤其是裝卸車輛中所使用的液壓迴路中，實現未進行裝卸作業時伴隨壓力損耗而產生的動力損耗之大幅削減。 According to the configuration of the present invention, it is possible to achieve a significant reduction in power loss due to pressure loss during unloading operations in an industrial vehicle such as a stacker including a loading and unloading device, particularly a hydraulic circuit used in loading and unloading vehicles. .
1‧‧‧液壓迴路 1‧‧‧Hydraulic circuit
2‧‧‧主泵(液壓泵) 2‧‧‧Main pump (hydraulic pump)
3‧‧‧副泵(液壓泵) 3‧‧‧Sub pump (hydraulic pump)
4‧‧‧分流閥 4‧‧‧Diverter valve
4a‧‧‧輸入端口 4a‧‧‧Input port
4b‧‧‧剩餘流輸出口 4b‧‧‧Remaining flow output
4c‧‧‧優先流輸出口 4c‧‧‧Priority flow output
5‧‧‧轉向機構 5‧‧‧Steering mechanism
6‧‧‧流量調整閥 6‧‧‧Flow adjustment valve
7‧‧‧槽 7‧‧‧ slot
8‧‧‧裝卸用致動器 8‧‧‧Moving and unloading actuators
9‧‧‧主通路 9‧‧‧Main pathway
10‧‧‧第1副通路 10‧‧‧1st secondary access
11‧‧‧旁通通路(第2副通路) 11‧‧‧ bypass path (second secondary path)
12‧‧‧切換閥 12‧‧‧Switching valve
12a‧‧‧盤簧 12a‧‧‧ coil spring
12b‧‧‧螺線管 12b‧‧‧ Solenoid
Claims (2)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| PCT/JP2012/082913 WO2014097423A1 (en) | 2012-12-19 | 2012-12-19 | Hydraulic circuit and cargo-handling vehicle |
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| Publication Number | Publication Date |
|---|---|
| TW201425740A true TW201425740A (en) | 2014-07-01 |
| TWI486529B TWI486529B (en) | 2015-06-01 |
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| Application Number | Title | Priority Date | Filing Date |
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| TW102144513A TWI486529B (en) | 2012-12-19 | 2013-12-05 | Hydraulic circuit and loading and unloading vehicle |
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| Country | Link |
|---|---|
| JP (1) | JP5896041B2 (en) |
| CN (1) | CN104870832B (en) |
| TW (1) | TWI486529B (en) |
| WO (1) | WO2014097423A1 (en) |
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| JP6577336B2 (en) * | 2015-11-05 | 2019-09-18 | 株式会社豊田自動織機 | Industrial vehicle |
| CN106762928B (en) * | 2017-01-17 | 2018-10-16 | 徐工集团工程机械有限公司 | Automobile hydraulic system and engineering truck with it |
| AU2018200354B2 (en) * | 2017-01-17 | 2023-02-23 | The Raymond Corporation | Variable hydraulic pressure relief systems and methods for a material handling vehicle |
| US10611401B2 (en) * | 2017-05-16 | 2020-04-07 | Zf Active Safety And Electronics U.S. Llc | Power steering apparatus |
| JP7024637B2 (en) * | 2018-07-13 | 2022-02-24 | 株式会社豊田自動織機 | Industrial vehicle |
| DE102019132884A1 (en) * | 2019-12-03 | 2021-06-10 | Danfoss Scotland Ltd. | Hydraulic system with a switch valve block for a hydraulically operated machine |
| DE102019132845A1 (en) * | 2019-12-03 | 2021-06-10 | Danfoss Scotland Ltd. | Switch valve block for a hydraulically operated machine |
| CN114506799B (en) * | 2022-04-20 | 2022-07-08 | 杭叉集团股份有限公司 | Forklift gantry joint action control method and control system |
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| JPH01128466U (en) * | 1988-02-26 | 1989-09-01 | ||
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| JPH0527423U (en) * | 1991-09-13 | 1993-04-09 | 株式会社小松製作所 | Transmission hydraulic circuit with priority to clutch operation |
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| CN101939550B (en) * | 2008-02-20 | 2013-12-25 | 株式会社小松制作所 | Oil pressure system and valve assembly used in oil pressure system |
| JP5113129B2 (en) * | 2008-09-01 | 2013-01-09 | 日産フォークリフト株式会社 | Hydraulic circuit device for industrial vehicles |
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| JP5763317B2 (en) * | 2010-09-14 | 2015-08-12 | ニチユ三菱フォークリフト株式会社 | Industrial vehicle |
| CN201962040U (en) * | 2011-02-21 | 2011-09-07 | 安徽合力股份有限公司 | Forklift hydraulic system with functions of priority and unloading |
-
2012
- 2012-12-19 JP JP2014552813A patent/JP5896041B2/en active Active
- 2012-12-19 WO PCT/JP2012/082913 patent/WO2014097423A1/en active Application Filing
- 2012-12-19 CN CN201280077751.2A patent/CN104870832B/en active Active
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Also Published As
| Publication number | Publication date |
|---|---|
| CN104870832A (en) | 2015-08-26 |
| WO2014097423A1 (en) | 2014-06-26 |
| JP5896041B2 (en) | 2016-03-30 |
| CN104870832B (en) | 2016-11-23 |
| TWI486529B (en) | 2015-06-01 |
| JPWO2014097423A1 (en) | 2017-01-12 |
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