JP6706545B2 - Hydraulic system - Google Patents

Description

According to the present invention, a hydraulic pump that sucks and discharges stored hydraulic oil to supply it to a load side and an electric motor that rotationally drives the hydraulic pump are mounted on an upper plate of an oil tank that stores hydraulic oil, and the oil tank is loaded from the load side. The present invention relates to a hydraulic device having a return filter that removes dust that is mixed in with hydraulic oil that flows back into the air.

In a conventional hydraulic system, a hydraulic pump and an electric motor that rotationally drives the hydraulic pump are mounted on the upper plate of an oil tank that stores hydraulic oil, and the hydraulic pump is rotationally driven to suck and discharge the hydraulic oil stored in the oil tank. Then, the hydraulic oil supplied to the actuator on the load side and returned from the actuator is returned to the oil tank (see, for example, Patent Document 1).
Further, there is one in which a return filter is attached to the upper wall of the tank main body, and dust mixed in the working oil flowing back from the actuator to the oil tank is removed by the return filter (for example, refer to Patent Document 2).

JP-A-6-42501 JP, 2000-249102, A

By the way, when trying to assemble the return filter disclosed in Patent Document 2 to the upper plate of the oil tank of the hydraulic device disclosed in Patent Document 1, an installation area for assembling the return filter to the upper plate is required, and the oil The tank becomes larger.

Further, in order to prevent the oil tank from becoming large in size, if a return filter is provided in the return pipe for hydraulic oil as disclosed in FIGS. 4 and 5 of Patent Document 2, the casing is removed from the filter body and the filter element is replaced. When doing so, the hydraulic oil flowing out from the removed part had to be collected, and the replacement work was troublesome.

An object of the present invention is to provide a hydraulic device that can facilitate the replacement work of the filter element without increasing the size of the oil tank.

In order to achieve such a subject, the present invention has taken the following means. That is,
On the upper plate of the oil tank that stores hydraulic oil inside, place the hydraulic pump that sucks and discharges the stored hydraulic oil and supplies it to the load side, and the electric motor that rotationally drives the hydraulic pump. A return pipe that circulates the working oil that flows back is provided, and a return filter that removes dust mixed in the working oil is installed in the return pipe.The return filter removes the inflow port and the dust that flows in the working oil from the load side. A filter body formed with an outlet for discharging the working oil, a filter element for removing dust mixed in the working oil, and a casing in which the filter element is housed inside and detachably attached to the filter body. The return pipe is connected between the load side and the inlet of the filter body, and the return pipe is connected between the outlet of the filter body and the oil tank, and the tip is immersed in the stored hydraulic oil. The return filter is composed of a second return pipe and is located vertically above the stored hydraulic oil in the oil tank. The filter body is movably mounted in the oil tank in the vertical direction and is stored by moving the filter body upward. This is a hydraulic device characterized in that the tip of the second return pipe immersed in hydraulic oil can be pulled out upward.

In this case, a mounting bracket is erected on the upper plate of the oil tank, a long hole extending vertically is formed in the mounting bracket, and the filter body is mounted on the mounting bracket by tightening a bolt member that passes through the long hole. May be. Further, in a state in which a mounting bracket is erected on the upper plate of the oil tank and the tip end portion of the second return pipe immersed in the stored hydraulic oil is pulled out by moving the filter body upward, The filter body may be lockable to the mounting bracket. The mounting bracket has a locking hole extending in the vertical direction and having a recess at the upper end, a locking member is provided on the second return pipe, and the locking member is locked in the recess of the locking hole. Then, the filter body may be locked to the mounting bracket. Further, in the return filter, the casing may be attached to the filter body attached to the attachment bracket so as to extend horizontally outward.

As described above in detail, in the invention according to claim 1, the return filter has a filter main body having an inlet for inflowing working oil from the load side and an outlet for outflowing working oil from which dust has been removed, It consists of a filter element that removes dust mixed in the hydraulic oil and a casing that has the filter element housed inside and is detachably attached to the filter body.The return pipe is between the load side and the inlet of the filter body. And a second return pipe that connects the outflow port of the filter body and the oil tank and has its tip immersed in the stored hydraulic oil. The return filter is a storage tank for the oil tank. Located vertically above the hydraulic oil, the filter body is vertically movably attached to the oil tank, and the upper end of the second return pipe immersed in the stored hydraulic oil is moved upward by moving the filter body upward. It was possible to withdraw. Therefore, when the filter body is moved upward and the tip of the second return pipe is pulled out above the oil level of the stored hydraulic oil, the hydraulic oil inside the return filter can flow through the second return pipe and flow out to the oil tank. Therefore, when the casing is removed from the filter body and the filter element is replaced, it is possible to reduce the flow of the working oil from the removed part and to eliminate the need to collect the working oil, thereby facilitating the replacement work of the filter element. Further, the return filter does not have to be assembled on the upper plate of the oil tank, and the size of the oil tank can be increased.

In the invention according to claim 2, a mounting bracket is erected on the upper plate of the oil tank, a long hole extending in the vertical direction is formed in the mounting bracket, and a filter is formed by tightening a bolt member inserted through the long hole. The body was attached to the mounting bracket. Therefore, the vertical position of the return filter can be set at an arbitrary position within the long hole, and the position of the tip of the second return pipe can be set accordingly, so that the optimum position according to the amount of stored hydraulic oil in the oil tank can be set. The tip of the second return pipe can be located in position.

In the invention according to claim 3, a mounting bracket is erected on the upper plate of the oil tank, and the tip of the second return pipe immersed in the stored hydraulic oil is moved upward by moving the filter body upward. The filter body can be locked to the mounting bracket when pulled out. Therefore, when the filter element is replaced by removing the casing from the filter body, the tip of the second return pipe can be temporarily fixed in a state of being pulled out above the oil level of the stored hydraulic oil, facilitating the replacement work of the filter element. You can

Further, in the invention according to claim 4, the mounting bracket has a locking hole extending in the vertical direction and having a recessed portion at the upper end, and a locking member is provided on the second return pipe to lock the locking member. The filter body can be locked to the mounting bracket by locking it in the recess of the hole. Therefore, when removing the casing from the filter body and replacing the filter element, the second return pipe can be easily temporarily fixed with the tip of the second return pipe pulled out above the oil level of the stored hydraulic oil, and the filter element replacement operation can be performed. Can be made even easier.

Further, in the invention according to claim 5, the return filter has the casing mounted on the filter main body mounted on the mounting bracket so as to extend outward in the horizontal direction. Therefore, a space can be secured in the vertical position of the filter body in the vertical direction, and the first return pipe and the second return pipe can be mounted in the vertical position of the filter body in the vertical direction, and the return can be performed. The filter, the first return pipe, and the second return pipe can be compactly arranged.

It is a front view of the hydraulic device showing one embodiment of the present invention. It is a left side view of FIG. It is a top view of FIG. FIG. 4 is an enlarged sectional view taken along the line AA of FIG. 3. It is the figure seen from the arrow B of FIG. FIG. 4 is an enlarged cross-sectional view showing a mounting state of the return filter different from that of FIG. 4. It is a principal part enlarged view which showed other embodiment of this invention. FIG. 7 is an enlarged view of a main part showing a mounting state of the return filter different from that of FIG. 7.

An embodiment of the present invention will be described below with reference to the drawings.
1 to 3, reference numeral 1 denotes a tank for storing hydraulic oil therein, which is formed in a substantially rectangular parallelepiped shape having an upper opening, and the upper opening is closed by a removable upper plate 2. An electric motor 3 rotationally drives the hydraulic pump 4, and is mounted and fixed on the upper plate 2 via a plurality of cushioning members 5 and a substrate member 6. The hydraulic pump 4 is fixed to one side surface of the electric motor 3 on the upper plate 2, and the rotational driving of the electric motor 3 sucks the stored hydraulic oil in the oil tank 1 from the suction pipe line 4A and discharges it to the discharge pipe line 4B. The hydraulic oil discharged to the discharge pipe line 4B is supplied to an actuator (not shown) on the load side. A protection member 7 is arranged above one side surface of the oil tank 1 for protecting an oil level gauge for visually observing the storage amount of the working oil from the outside, and a discharge port for discharging the stored working oil is provided below the one side surface of the oil tank 1. A plug member 8 for detachably closing the plug is provided. On the upper plate 2 of the oil tank 1, an oil inlet/air breather 9 for injecting hydraulic oil into the oil tank 1, a plurality of hook members 10 for lifting and moving the apparatus, and a drain of the hydraulic pump 4 are introduced. A cooler 13 is provided which is introduced from the pipe line 11 and cooled, and the cooled drain is returned to the oil tank 1 from the drain lead-out pipe line 12. An oil pan 14 having a larger area than the oil tank 1 is installed below the oil tank 1 to collect the leaked hydraulic oil.

Reference numeral 15 is a return pipe that circulates the working oil flowing back to the oil tank 1 from the actuator side, and is provided with a return filter 16 for removing dust mixed in the working oil. As shown in FIGS. 4 to 6, the return filter 16 includes a filter main body 19 having an inflow port 17 for inflowing the working oil from the actuator side, an outflow port 18 for outflowing the working oil from which dust has been removed, and It is composed of a filter element 20 that removes dust that is mixed in, and a casing 21 that accommodates the filter element 20 inside and is detachably attached to the filter body 19. Reference numeral 22 denotes a valve element housed in the filter body 19, which is urged by a spring 23 to be seated on a valve seat 24 to block between the inflow port 17 and the outflow port 18. The valve body 22 separates from the valve seat 24 when the acting force based on the pressure of the hydraulic oil on the side of the inflow port 17 exceeds the force of the spring 23 due to the clogging of the filter element 20, and the space between the inflow port 17 and the outflow port 18 is removed. Communicate.

Reference numeral 25 denotes a plate-shaped mounting bracket, which is formed in a substantially rectangular shape and stands on the upper plate 2 of the oil tank 1. The mounting bracket 25 has two elongated holes 26A and 26B extending vertically. 27A and 27B are bolt members, which are inserted into the long holes 26A and 26B and screwed into the screw holes 19A of the filter body 19. The filter body 19 is attached to the attachment bracket 25 by tightening bolt members 27A and 27B, and is attached so as to be vertically movable within the range of the long holes 26A and 26B.

The return pipe 15 connects the first return pipe 28 that connects the actuator side and the inflow port 17 of the filter body 19 with the outflow port 18 of the filter body 19 and the oil tank 1 to connect the tip 29A. The second return pipe 29 is immersed in the stored hydraulic oil. The first return pipe 28 is flexible, is provided to be bendable so as not to hinder the vertical movement of the filter body 19, and is screwed to the inflow port 17. The second return pipe 29 is formed from a steel pipe in a linear shape, and the disc-shaped sealing member 30 arranged on the upper plate 2 hermetically penetrates the upper plate 2 to screw it to the outflow port 18. Then, the second return pipe 29 allows the tip portion 29A immersed in the stored hydraulic oil by the upward movement of the filter body 19 to be pulled out above the oil surface T of the stored hydraulic oil.

Next, the operation of such a configuration will be described.
When the hydraulic pump 4 is rotationally driven by the electric motor 3, the hydraulic pump 4 sucks the hydraulic oil stored in the oil tank 1 from the suction pipe 4A and discharges it to the discharge pipe 4B. This discharged hydraulic oil is supplied to an actuator (not shown). Supplied. The return oil from the actuator flows through the first return pipe 28, enters the inside of the casing 21 through the inflow port 17 of the return filter 16, the dust is removed by the filter element 20, and flows through the second return pipe 29 through the outflow port 18. Return to the oil tank 1. At this time, the valve body 22 of the return filter 16 is urged by the spring 23 and seated on the valve seat 24 to block between the inflow port 17 and the outflow port 18.

In this state, if the filter element 20 of the return filter 16 is clogged, it becomes difficult for the hydraulic oil to flow. When the pressure of the hydraulic oil on the side of the inflow port 17 increases due to the eyes of the filter element 20 and the acting force based on this pressure exceeds the force of the spring 23, the valve body 22 separates from the valve seat 24 and flows into the inflow port 17. It communicates with the outlet 18. The hydraulic oil that has flowed into the inflow port 17 directly flows through the second return pipe 29 from the outflow port 18 without passing through the filter element 20 and is returned to the oil tank 1.

In order to replace the clogged filter element 20 with a new filter element 20, the operator loosens the bolt members 27A and 27B with the hydraulic pump 4 stopped, and as shown in FIG. Of the second return pipe 29 is pulled upward from the oil surface T of the stored hydraulic oil, the bolt members 27A and 27B are tightened, and the filter body 19 is fixed to the mounting bracket 25 at the upper position. .. Then, the hydraulic oil remaining inside the return filter 16 is discharged from the tip end portion 29A of the second return pipe 29 into the space above the stored hydraulic oil in the oil tank 1.

In this state, the casing 21 is removed from the filter body 19, and the filter element 20 is replaced with a new filter element 20. Then, when the casing 21 is attached to the filter body 19 again, the bolt members 27A and 27B are loosened, the filter body 19 of the return filter 16 is moved downward toward the original position in FIG. 4, and the tip portion of the second return pipe 29 is moved. When 29A is returned to the original position in FIG. 4 where it is immersed in the stored hydraulic oil, the bolt members 27A and 27B are tightened to fix the filter body 19 to the mounting bracket 25.

When the hydraulic pump 4 is rotationally driven after replacement with a new filter element 20, the hydraulic oil at the inflow port 17 starts to flow through the filter element 20, the pressure on the inflow port 17 side decreases, and the valve body 22 springs. The valve seat 24 is seated by 23 force to shut off the space between the inflow port 17 and the outflow port 18.

With such an operation, the return filter 16 removes dust mixed in the hydraulic fluid, and a filter body 19 having an inflow port 17 for inflowing the operating oil from the actuator side and an outflow port 18 for outflowing the operating oil from which dust has been removed. Of the filter element 20 and a casing 21 in which the filter element 20 is housed inside and detachably attached to the filter body 19, and the return pipe 15 is provided between the actuator side and the inflow port 17 of the filter body 19. A return filter comprising a first return pipe 28 to be connected and a second return pipe 29 which connects the outflow port 18 of the filter body 19 and the oil tank 1 and immerses the tip 29A in the stored hydraulic oil. Reference numeral 16 is positioned vertically above the stored hydraulic oil in the oil tank 1, the filter body 19 is movably attached to the oil tank 1 in the vertical direction, and is immersed in the stored hydraulic oil by moving the filter body 19 upward. The tip portion 29A of the second return pipe 29 can be pulled out upward. Therefore, when the filter body 19 is moved upward and the tip portion 29A of the second return pipe 29 is pulled out above the oil level T of the stored hydraulic oil, the hydraulic oil inside the return filter 16 flows through the second return pipe 29. Can flow out to the oil tank 1, so that when the casing 21 is removed from the filter body 19 and the filter element 20 is replaced, it is possible to reduce the outflow of the operating oil from the removed portion and to eliminate the need to collect the operating oil. The replacement work of the filter element 20 can be facilitated. Further, the return filter 16 does not have to be attached to the upper plate 2 of the oil tank 1 and can be made without increasing the size of the oil tank 1.

Further, a mounting bracket 25 is erected on the upper plate 2 of the oil tank 1, elongated holes 26A and 26B extending in the vertical direction are formed in the mounting bracket 25, and bolt members 27A and 27B are inserted through the elongated holes 26A and 26B. The filter body 19 was attached to the mounting bracket 25 by tightening. Therefore, the vertical position of the return filter 16 can be set at an arbitrary position within the long holes 26A and 26B, and the position of the tip end portion 29A of the second return pipe 29 can be set accordingly, so that the oil tank 1 is stored. The tip portion 29A of the second return pipe 29 can be located at the optimum position according to the amount of hydraulic oil.

Further, in the return filter 16, the casing 16 is attached to the filter main body 19 attached to the attachment bracket 25 so as to extend outward in the horizontal direction. Therefore, a space can be secured in the vertical position of the filter body 19 in the vertical direction, and the first return pipe 28 and the second return pipe 29 can be mounted in the vertical position of the filter body 19 in the substantially vertical direction. The return filter 16, the first return pipe 28, and the second return pipe 29 can be compactly arranged.

7 and 8 show another embodiment of the present invention. The same parts as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted. Only different parts will be described.
In FIG. 7 and FIG. 8, a locking hole 32 extending vertically is formed in a mounting bracket 31 standing on the upper plate 2 of the oil tank 1, and a recess 32A is formed at the upper end of the locking hole 32. Is formed. In addition, the mounting bracket 31 is formed with two elongated holes 33A and 33B that extend in the vertical direction and open to the upper end side. The bolt members 27A and 27B are in contact with the lower ends of the elongated holes 33A and 33B, respectively, inserted through the elongated holes 33A and 33B, and screwed into the filter body 19.

Reference numeral 34 denotes a locking member attached to the second return pipe 29, in a state where the locking hole 32 is inserted, and the second return pipe 29 immersed in the stored hydraulic oil is pulled out by the upward movement of the filter body 19, It can be locked in the recess 32A. The locking member 34 locks the filter body 19 at a position above the mounting bracket 31 while being locked in the recess 32</b>A of the locking hole 32.

Reference numeral 35 is a pressure gauge interposed between the first return pipe 28 and the filter body 19, and displays the pressure of the hydraulic oil flowing from the first return pipe 28 to the filter body 19.

Next, the operation of such a configuration will be described.
To replace the clogged filter element 20 with a new filter element 20, the operator loosens the bolt members 27A and 27B with the hydraulic pump 4 stopped, and as shown in FIG. Is moved upward, the locking member 34 is locked in the recess 32A of the locking hole 32, and the filter body 19 is locked in the mounting bracket 31 at the upper position. Then, the tip portion 29A of the second return pipe 29 is drawn upward from the oil level T of the stored working oil, and the working oil remaining inside the return filter 16 is fed from the tip portion 29A of the second return pipe 29 to the oil tank 1. Of the stored hydraulic oil is discharged to the upper space.

In this state, the casing 21 is removed from the filter body 19, and the filter element 20 is replaced with a new filter element 20. Then, when the casing 21 is attached to the filter body 19 again, the locking state of the locking member 34 and the recessed portion 32A is released, and the filter body 19 of the return filter 16 is stored in the tip portion 29A of the second return pipe 29. It moves to the original position of FIG. 7 immersed in it, and the bolt members 27A and 27B are tightened, and the filter body 19 is fixed to the mounting bracket 31.

With this operation, when the filter body 19 is moved upward and the tip portion 29A of the second return pipe 29 is pulled out above the oil level T of the stored hydraulic oil, the hydraulic oil inside the return filter 16 is moved in the same manner as in the embodiment. Can flow through the second return pipe 29 and flow out to the oil tank 1. Therefore, when the casing 21 is removed from the filter body 19 and the filter element 20 is replaced, the operating oil is mitigated from flowing out from the removed location. It is possible to eliminate the need for oil recovery and facilitate the replacement work of the filter element 20. Further, the return filter 16 does not have to be attached to the upper plate 2 of the oil tank 1 and can be made without increasing the size of the oil tank 1. Further, since the vertical position of the return filter 16 can be set at any position in the long holes 33A and 33B, and the position of the tip portion 29A of the second return pipe 29 can be set accordingly, the storage operation of the oil tank 1 can be performed. The tip portion 29A of the second return pipe 29 can be located at the optimum position according to the amount of oil.

Further, a mounting bracket 31 is erected on the upper plate 2 of the oil tank 1, and the tip portion 29A of the second return pipe 29 immersed in the stored hydraulic oil is pulled out by moving the filter body 19 upward. In this state, the filter body 19 can be locked to the mounting bracket 31. Therefore, when the casing 21 is removed from the filter body 19 and the filter element 20 is replaced, the tip end portion 29A of the second return pipe 29 can be temporarily fixed while being pulled out above the oil level T of the stored hydraulic oil, The replacement work of the element 20 can be facilitated.

Further, the mounting bracket 31 has a locking hole 32 extending in the vertical direction and having a recessed portion 32A at the upper end, a locking member 34 is provided on the second return pipe 29, and the locking member 34 is attached to the locking hole 32. The filter body 19 can be locked to the mounting bracket 31 by being locked in the recess 32A. Therefore, when the casing 21 is removed from the filter body 19 and the filter element 20 is replaced, the tip portion 29A of the second return pipe 29 can be easily temporarily fixed in a state where it is pulled out above the oil level T of the stored hydraulic oil. The replacement work of the filter element can be further facilitated.

In each of the above-described embodiments, the hydraulic pump 4 is fixed to one side surface of the electric motor 3, but the hydraulic pump may be mounted and fixed on the upper plate of the oil tank. Further, two long holes 26A, 26B or 33A, 33B extending in the vertical direction are formed in the mounting bracket 25 or 31, but the number is not limited to this, and one or three or more long holes may be formed. Good. Further, the locking member 34 attached to the second return pipe 29 is locked in the recess 32A of the locking hole 32 so that the filter body 19 can be locked in the mounting bracket 31, but the present invention is not limited to this. Instead, the bolt member may be inserted into the recess 32A of the locking hole 32 and screwed into the filter body 19 so that the filter body 19 can be locked to the mounting bracket 31.

1: Oil tank 2: Upper plate 3: Electric motor 4: Hydraulic pump
15: Return pipe 16: Return filter 17: Inflow port 18: Outflow port 19: Filter body 20: Filter element 21: Casing 25, 31: Mounting brackets 26A, 26B, 33A, 33B: Long holes 27A, 27B: Bolt member 28 : First return pipe 29: Second return pipe 29A: Tip part 32 of second return pipe 32: Locking hole 32A: Recess 34: Locking member

Claims (5)

On the upper plate of the oil tank that stores hydraulic oil inside, place the hydraulic pump that sucks and discharges the stored hydraulic oil and supplies it to the load side, and the electric motor that rotationally drives the hydraulic pump. A return pipe that circulates the working oil that flows back is provided, and a return filter that removes dust mixed in the working oil is installed in the return pipe.The return filter removes the inflow port and the dust that flows in the working oil from the load side. A filter body formed with an outlet for discharging the working oil, a filter element for removing dust mixed in the working oil, and a casing in which the filter element is housed inside and detachably attached to the filter body. The return pipe is connected between the load side and the inflow port of the filter body, and the return pipe is connected between the outflow port of the filter body and the oil tank, and the tip is immersed in the stored hydraulic oil. The return filter is composed of a second return pipe and is located vertically above the stored hydraulic oil in the oil tank. The filter body is movably mounted in the oil tank in the vertical direction and is stored by moving the filter body upward. A hydraulic system characterized in that the tip of the second return pipe immersed in hydraulic oil can be pulled out upward. A mounting bracket is erected on the upper plate of the oil tank, an elongated hole extending in the vertical direction is formed in the mounting bracket, and the filter body is attached to the mounting bracket by tightening a bolt member inserted through the elongated hole. The hydraulic system according to claim 1, wherein the hydraulic system is a hydraulic system. The filter main body in a state where a mounting bracket is erected on the upper plate of the oil tank and the tip of the second return pipe immersed in the stored hydraulic oil is pulled out by moving the filter main body upward. The hydraulic device according to claim 1, wherein the mounting bracket is engageable with the mounting bracket. The mounting bracket has a locking hole that extends in the vertical direction and has a recessed portion at the upper end, a locking member is provided on the second return pipe, and the locking member is locked in the recessed portion of the locking hole. The hydraulic device according to claim 3, wherein the filter body can be locked to a mounting bracket. The hydraulic device according to any one of claims 2 to 4, wherein in the return filter, the casing is attached to the filter body attached to the attachment bracket so as to extend outward in the horizontal direction.

Images