JP2003026378A - Hydraulic cylinder of hydraulic type elevator and hydraulic circuit using hydraulic cylinder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a hydraulic cylinder for a hydraulic type elevator capable of taking out its piston from the over-part even if the installation area is narrow and easily performing at the site the inspecting and maintenance operations for a seal such as packing, seal ring, etc., and also a bearing metal (wear ring). SOLUTION: The hydraulic cylinders 5 and 5A of the hydraulic type elevators 1 and 1A to elevate and sink a car for carrying parsons and/or objects are composed of pistons 20 and 48 inserted into cylinder tube 17 and 47 tightly for sealing a pressure oil, bottom covers 18 and 18A removably attached to the tops of the cylinder tubes, and piston rods 23 and 53 whose tips on one end having penetrated the under-part of the cylinder tubes are attached to the foundation where the pistons are installed in the over-part on the other end.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic cylinder of a hydraulic elevator and a hydraulic circuit using the hydraulic cylinder, and more particularly, to a hydraulic circuit that can be used for maintenance and inspection in a narrow space with a hydraulic circuit of an energy-saving hydraulic elevator. Regarding cylinders.

[0002]

2. Description of the Related Art Conventionally, a hydraulic elevator has used a hydraulic jack that raises and lowers a cage by protruding a ram from a cylinder tube. This hydraulic jack requires a hydraulic pump with a large discharge amount in order to obtain a predetermined ascending / descending speed, and a large amount of energy is lost because the speed is lowered by controlling the speed while squeezing the return oil.

Conventionally, as an improvement, an actual energy saving type hydraulic elevator shown in FIG. 4 has been proposed in Japanese Utility Model Laid-Open No. 7-53162 (name of device: indirect hydraulic elevator). According to the publication, indirect / hydraulic elevator 1
00 is provided with a car 102 that moves up and down in the hoistway 101,
The upper end surface 104a of the tube 104 of the hydraulic cylinder 103 is fixed to the upper part 101a of the hoistway 101, and the hydraulic cylinder 103 is attached so that the rod 105 extends downward. The hydraulic cylinder 103 is attached to a narrow place in the hoistway 101 so as to be located on one side surface of the car 102, and has a rope sheave 106 at the lower end of the rod 105. One end of the rope 107 is connected to the car 102, and the other end is connected to the rope sheaves 108, 109 and the rope sheep 106.
It is connected to the rope attachment shaft 110 of the hoistway 101 via. As a result, when the rod 105 of the hydraulic cylinder 103 extends downward, the car 102 rises, and when the rod 105 contracts upward, the car 102 descends.
In the conventional indirect / hydraulic elevator 100 of this type, the hydraulic cylinder 103 is mounted in the hoistway 101 so that the rod 105 extends upward, and when the car 102 is raised, the rod 105, the rope sheave 106, and the like are removed. At the same time, the weight is increased, and the weight thereof tends to increase the hydraulic pressure of the hydraulic cylinder 103. On the other hand, in the publication, their weight acts in the direction of reducing the hydraulic pressure. Further, it is described that the purpose is extremely easily achieved by suspending the counterweight 111 on the lower end of the rope sheave 106 in order to reduce the hydraulic pressure.

Further, the present applicant has proposed Japanese Patent Publication No. 2000-346012 as an energy-saving hydraulic lifting device. According to the publication, as shown in FIG. 5, a hydraulic lifting device 120 includes a sheave 125 in which an upper end block 122 at an upper end of a piston rod 121 is attached with first pulley 123 and balance weights 124 and 124 having substantially the same load left and right. And are fixed to the hydraulic cylinder 126.
In the hydraulic lifting device 120, the rope 128 having one end fixed to the structure 127 is connected to the first pulley 123 and the structure 1.
Second pulley 129 and third pulley 130 fixed to 27
To the loading car 131 (hereinafter, the car 13
1) is attached. This hydraulic lifting device 120
With the balance weight 124, the total weight of the car 131 and the load on which the car 131 is loaded is offset to some extent by the balance weight 124, so that the energy saving effect of the electric motor 132 is obtained.

In the above hydraulic cylinder 126, the reversible rotary hydraulic pump motor 133 supplies hydraulic oil from the upper oil supply / drain port 135 of one cylinder tube 134 to the cylinder upper chamber 1.
36, the piston 137, that is, the piston rod 121 moves downward to move the piston rod 121.
The hydraulic oil therein is discharged from the lower supply / discharge oil port 139 at the lower end of the hollow pipe 138. Reversible rotary hydraulic pump motor 13
When 3 supplies the hydraulic oil from the other lower oil supply / drain port 139, the piston rod 121 is pushed upward and the hydraulic oil between the inner diameter surface of the cylinder tube 134 and the outer diameter surface of the piston rod 121 is supplied to the upper portion. Oil drain port 13
As a result, the piston rod 121 is vertically reciprocated.

As shown in FIG. 6, the hydraulic cylinder 126 has a ring member 1 at the lower end of a cylinder tube 134.
The inner diameter portion of 41 is fitted and these are fixed by welding.
Then, the bottom cover 142 having a shape that is in close contact with the lower end surface of the cylinder tube 134 and that fits into the inner diameter surface of the cylinder tube 134 and that has an opening through which the hollow pipe 138 is inserted in the center is fixed by the bolt 143. The bottom cover 142 and the cylinder tube 1
In order to ensure liquid-tightness, the fitting portion with the inner diameter surface of 34 is O
A ring 144 was attached. In addition, at the opening of the bottom cover 142 that penetrates the hollow pipe 138, the hollow pipe 13
A flange 145, which has a shape that fits on the inner diameter surface of No. 8 and is in close contact with the lower surface of the bottom cover 142 and further has a lower oil supply / discharge port 139 formed in the center, is fixed with a bolt 146. It should be noted that the O-ring 1 is provided in both the fitting portion of the inner surface of the hollow pipe 138 and the close contact portion of the lower surface of the bottom cover 142.
47 and 148 were attached. Such a bottom cover 14
2, the bottom cover 142 and the hollow pipe 138 can be removed by removing the bolt 143, and therefore the piston 137 can be easily pulled out to the outside of the cylinder tube 134. Therefore, the packings 150, 151 and It is proposed that the bearing metals 152 and 153 can be easily replaced.

[0007]

Conventionally, since the hydraulic elevator is installed in a narrow place as described above, it is strongly desired to improve the maintainability of the hydraulic cylinder for raising and lowering the car. However, in Japanese Utility Model Laid-Open No. 7-53162, since the upper end of the tube of the hydraulic cylinder is attached to the hoistway, the packing, seal ring and bearing metal (wafer ring) attached to the piston of the hydraulic cylinder are attached. ), Or. If the rod packing leaks or is damaged, the entire hydraulic cylinder must be taken out through the hoistway, and then the hydraulic cylinder must be disassembled to inspect or replace the packing, seal ring and bearing metal. As a result, it becomes difficult to disassemble on site, especially replacement in the hoistway, and after removing the hydraulic cylinder and balance weight, it is necessary to work to take it out of the hoistway, which requires a lot of man-hours for maintenance such as inspection and replacement. There is a problem that it takes.

In Japanese Patent Publication No. 2000-346012, the bottom cover 142 and the hollow pipe 138 can be removed by removing the bolt 143, and the piston 137 can be easily pulled out to the outside of the cylinder tube 134. Packing 150 for piston 134, 1
It is described that the 51 and the bearing metal 152 can be easily replaced. However, since the lower end of the bottom cover 142 is attached to the foundation 127a of the structure, it is impossible to directly remove the bottom cover 142, and the entire hydraulic cylinder is lifted by the hoistway as in the above-described embodiment. After taking it out, the hydraulic cylinder must be disassembled and the packing, seal ring and bearing metal must be inspected or replaced. For this reason, similarly to the above, after removing the hydraulic cylinder and the balance weight, it is necessary to take out the work to the outside of the hoistway, which requires a lot of man-hours for maintenance such as inspection and replacement.

In Japanese Utility Model Laid-Open No. 7-53162 and Japanese Patent Application Laid-Open No. 2000-346012, the hydraulic cylinders that are difficult to inspect and replace as described above are used. It is desired to provide a hydraulic circuit for a lift-type elevator, which can save energy and can be easily maintained.

The present invention has been made in view of the above problems, and a first object thereof is to take out a piston from above even in a place having a small installation area, and to seal a packing, a seal ring or the like at that place, or a bearing metal ( (EN) A hydraulic cylinder of a hydraulic elevator that allows easy inspection and maintenance of a wear ring) or a rod packing. A second object of the present invention is to provide a hydraulic circuit using a hydraulic cylinder of a hydraulic elevator that is easy to maintain while saving energy.

[0011]

In order to achieve the above object, in the first invention of the hydraulic cylinder of the hydraulic elevator,
A hydraulic cylinder for a hydraulic elevator for moving a person and / or a luggage-carrying basket up and down, which is pivotally inserted into a cylinder tube and seals pressure oil, and is detachably attached to an upper end portion of the cylinder tube. And a bottom end and a tip end on one end side that penetrates the lower portion of the cylinder tube is attached to the foundation, and a piston rod is provided with the piston on the upper end on the other end side. Alternatively, in the second invention of the hydraulic cylinder, a person and / or
Alternatively, a hydraulic cylinder of a hydraulic elevator for lifting and lowering a luggage-carrying basket, which is pivotally inserted into a cylinder tube to seal pressure oil and a bottom cover detachably attached to an upper end of the cylinder tube. And a tip end on one end side that penetrates the lower side of the cylinder tube is attached to the foundation, and a piston rod provided with the piston at the upper end on the other end side and one end face side is attached to the cylinder tube. In addition, a rod that penetrates the piston and has the other end surface side disposed in the piston rod, and a reduction chamber provided between the cylinder tube and the piston rod on the lower side of the piston, The inside of the piston rod is composed of an extension chamber formed by the rod. In this case, at the time of disassembly, after removing the bottom cover with the tip end on one end side being attached to the foundation, the cylinder tube is lowered to project the piston, or the piston is located above the cylinder tube. Is taken out so that the packing, seal ring or bearing metal of the piston can be replaced. Further, it is preferable that the total length La of the cylinder tube is shorter than the slidable length Lo of the piston rod slidably inserted in the cylinder tube. A first invention of a hydraulic circuit of a hydraulic elevator using this hydraulic cylinder is a hydraulic circuit in which a balance weight is attached to generate a lower hydraulic pressure than a hydraulic pressure for raising and lowering a luggage carrying car (WC) to reduce power of a drive source. In a hydraulic circuit of a rotary elevator, at least a piston that is pivotally inserted into a cylinder tube and seals pressure oil, and a tip end on one end side that penetrates the lower part of the cylinder tube are attached to a foundation and the other end side. A piston rod provided with the piston above, and a hydraulic cylinder having a lift chamber provided between the cylinder tube and the piston rod on the lower side of the piston,
When the hydraulic elevator is raised, the pressure oil of the fixed volume hydraulic pump is supplied to the lifting chamber through the check valve and the flow meter to extend the hydraulic cylinder, and when the hydraulic elevator is lowered, By operating the lowering electromagnetic servo valve disposed on the downstream side of the check valve to connect the elevating chamber and the tank, the elevating chamber is controlled by the flow meter or the lowering electromagnetic servo valve according to the oil pressure and / or oil temperature of the elevating chamber. The hydraulic cylinder is reduced in size while controlling the flow rate discharged from the hydraulic cylinder. Alternatively, a second invention of the hydraulic circuit is a hydraulic circuit of a hydraulic elevator in which the hydraulic pressure of a hydraulic cylinder that raises and lowers a person and / or a luggage-carrying basket is reduced to a low hydraulic pressure by attaching a balance weight, At least a piston that is pivotally inserted into the cylinder tube and seals the pressure oil, and a tip end on one end side that penetrates the lower part of the cylinder tube is attached to the foundation, and the piston is attached to the upper part on the other end side. With the provided piston rod,
A rod having one end surface side attached to the cylinder tube and penetrating the piston, and the other end surface side being disposed in the piston rod, and the cylinder tube and the piston rod on the lower side of the piston. A hydraulic cylinder having a reduction chamber provided therebetween and an extension chamber formed by the rod inside the piston rod is provided, and one side is connected to the reduction chamber via a reduction pilot check valve, The other side is connected to the extension chamber via the extension pilot check valve and is driven by a drive source, and the bidirectional rotary hydraulic pump / motor and the reduction pilot check valve and the extension pilot check valve are respectively provided. Check valves installed in the pilot pipes connected upstream and downstream, and the highest It has a configuration comprising a pilot pressure electromagnetic switching valve for outputting one of closing command or open command to the reduced pilot with check valve and extension pilot with check valves receiving the lot pressure. In this case, the pilot pressure solenoid operated directional control valve outputs a closing command to the reduction pilot check valve and the extension pilot check valve when the hydraulic elevator is stopped, and
It is designed to output an opening command when moving up and down.

[0012]

When the hydraulic cylinder of the above construction is used in a hydraulic elevator, the tip of the piston rod is detachably attached to the foundation of the hoistway and the piston is attached to the other end. . The piston is pivotally inserted into the cylinder tube, seals the pressure oil to allow the cylinder tube to slide vertically with respect to the piston, and expands and contracts the hydraulic cylinder. Further, a bottom cover is detachably attached to the upper end portion of the cylinder tube, and by removing the bottom cover, the cylinder tube can move downward and the piston can be projected from the upper end surface of the cylinder tube. At this time, the total length L of the cylinder tube
Since a is shorter than the slidable length Lo of the piston rod slidably inserted in the cylinder tube, the piston can protrude from the upper end surface of the cylinder tube. As a result, the packing, seal ring, or thrust bearing attached to the piston can be easily replaced with the piston rod attached to the base. Similarly, the piston can be taken out from the upper end surface of the cylinder tube with the piston rod still attached to the base, and the packing, seal ring, or thrust bearing can be easily replaced. Further, after removing the piston rod from the foundation, it is possible to pull up to the inside upper part of the head cover, and at the installation position, inspect and replace the rod packing from below the head cover. By using this hydraulic cylinder in a hydraulic elevator, the hydraulic circuit of the hydraulic elevator can be easily maintained.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a hydraulic cylinder of a hydraulic elevator according to the present invention and a hydraulic circuit using the hydraulic cylinder will be described below with reference to the drawings. FIG. 1 is an overall configuration diagram of the hydraulic elevator according to the first embodiment. The same parts as those of the conventional example are designated by the same reference numerals and the description thereof will be omitted. The hydraulic elevator of the present invention is installed in a narrow space inside a structure 127 similar to the conventional hoistway 101. Figure 1
In the hydraulic elevator 1 of the first embodiment, a car 131 for loading a person and / or luggage, a pulley 3 and a hydraulic cylinder 5 for moving the car 131 up and down, and oil supply / discharge to / from the hydraulic cylinder 5. And a hydraulic circuit 7 that operates. The hydraulic cylinder 5 and the hydraulic circuit 7 form a hydraulic device.

In the hydraulic elevator 1 of the first embodiment, the pulley 3 includes a first pulley 123, a balance weight 124, a sheave 125, a rope 128, and a second pulley 12.
9. The balance weight 124, which is formed by the third pulley 130, offsets the total weight of the car 131 and the load on which the car 131 is mounted to some extent when the car is lifted, so that the energy saving effect of the electric motor 8 as a drive source is obtained. To be The weight WB of the balance weight 124 is 1
It is larger than half (1/2) of the added weight WA of the own weight WC of 31 and the loading weight WL on the car 131 [WB> WA /
2 = (WC + WL) / 2].
Therefore, in the hydraulic elevator 1, the weight WB of the balance weight 124 causes the head chamber 1 of the hydraulic cylinder 5 to move.
Oil pressure is constantly occurring at 1.

The hydraulic cylinder 5 of the hydraulic elevator 1 is
It is formed by the head chamber 11 and the bottom chamber 12. The head chamber 11 is connected to the hydraulic circuit 7 by the head port 11a,
The bottom chamber 12 is connected to the oil tank 13 by the bottom port 12a. Alternatively, the bottom chamber 12 may be supplied with a lubricant (not shown), and the atmosphere may be sucked and discharged through a dehumidifying device. The hydraulic cylinder 5 includes a cylinder tube portion 14 and a piston portion 1.
5 are formed. In the cylinder tube portion 14, a cylinder tube 17 is formed by a hollow tube, and the cylinder tube 17 is provided with a bottom chamber 12 above the drawing. The bottom chamber 12 is a cylinder tube 17
Inner diameter surface 17a, bottom cover 18, and piston 20
It is formed by. The bottom cover 18 has bolts 19
It is detachably attached.

The head chamber 11 below the cylinder tube portion 14 is formed by the inner diameter surface 17a of the cylinder tube 17, the cylinder head 17b, and the piston 20. A piston rod 23 penetrates the hole 21 of the cylinder head 17b, and the piston rod 23 slidably supports the cylinder tube 17. A rod packing 24 is provided in the hole 21 of the cylinder head 17b to abut the piston rod 23 to seal the pressure oil in the head chamber 11. Alternatively, although not shown, the cylinder head 17b is provided with a head cover of a normal structure to be attachable and detachable by bolts, and a bush, a cylinder seal, a gland, and an O-ring are assembled to seal the pressure oil in the head chamber 11, and the piston rod 23 May be taken out.

In the piston portion 15, the piston 20 is pivotally inserted into the inner diameter surface 17a of the cylinder tube 17. A piston rod 23 is formed integrally with the piston 20, and the head chamber 1 is provided inside the piston rod 23.
1 and a passage hole 26 connecting to the head port 11a. The piston rod 23 is attached to the cylinder head 17
A tip portion 23a, which penetrates through the hole 21 of b and is located below in the figure, is attached to a bracket 25 via a pin 24 that penetrates through the tip portion 23a. Pin 24 is nut 24
It is fixed to the bracket 25 by a. The bracket 25 is a structure 127 such as an anchor bolt (not shown).
Attached to the foundation 127a of the. Rod packing 24
For inspection and replacement, first, the bottom cover 18 is removed from the cylinder tube 17, and the pin 24 is pulled out from the tip portion 23a of the piston rod 23. Then, the piston 20 is pulled up until the lower end portion 23a of the piston rod 23 in the figure is located above the inside of the cylinder head 17b. As a result, the rod packing 24, when installed, has the hole 2 of the cylinder head 17b at the installed position from below in the drawing.
It can be easily inserted and replaced. Alternatively, the piston 20 and the piston rod 23 may be configured separately as shown by the chain double-dashed line, and formed by a nut 27 so that only the piston 20 can be taken out above the cylinder tube 17.

A piston seal ring 28 and a bearing metal 29 are provided between the piston 20 and the cylinder tube 17.
(Hereinafter, referred to as wear ring 29) is provided.
The piston 20 is pivotally inserted into the cylinder tube 17, a piston seal ring 28 blocks the pressure oil in the head chamber 11 from leaking to the bottom chamber 12, and a wear ring 29 receives a thrust load. As a result, the hydraulic cylinder 5 seals the pressure oil with the piston 20, and the cylinder tube 17 is expanded and contracted with respect to the piston 20 in a vertically slidable manner in the drawing. The bottom chamber 12 returns the oil leaked from the head chamber 11 to the oil tank 13 and sucks the oil from the oil tank 13 when the hydraulic cylinder 5 extends. In the hydraulic cylinder 5 having the above structure, the total length La of the cylinder tube 17 is formed shorter than the slidable length Lo of the piston rod 23 slidably inserted in the cylinder tube 17. The slidable length Lo of the piston rod 23 is, for example, as shown in FIG.
Cylinder head 17b has piston rod 2
3 is set in a range that does not overlap the hole 26.

With the above construction, when the cylinder tube 17 is lowered as shown by the chain double-dashed line Tp, the piston 20 projects from the upper surface 17d of the cylinder tube 17, so that the piston seal ring 28 used for the piston 20 is used. And / or the wear ring 29 can be easily inspected and replaced, and the maintainability is improved. Particularly, in this hydraulic cylinder 5, by removing the cylinder cover 18 and then pulling down the cylinder tube 17 in that state, the piston seal ring 28 for the piston seal ring 28 is left at the installed position.
And / or the wear ring 29 can be inspected and replaced. Further, the rod packing 24 can be inspected and replaced from below at the installation position by pulling the piston rod 23 upward inside the cylinder head 17b. As a result, the hydraulic cylinder 5 does not need to be carried out from a narrow place, and the maintainability is significantly improved. Or
After removing the bottom cover 18, by removing the nut 27 from above, the piston 20 is taken out upward, and the piston seal ring 28 and / or the wear ring 29 can be easily inspected and replaced. At this time, the total length of the hydraulic cylinder 5 at the minimum contraction can be shortened.

The hydraulic cylinder 5 is expanded by receiving pressure oil in the head chamber 11 from a hydraulic source such as a fixed displacement hydraulic pump 30 (hereinafter referred to as hydraulic pump 30) of the hydraulic circuit 7 described later. On the contrary, the hydraulic cylinder 5 can be reduced in size by draining the pressure oil in the head chamber 11 by the hydraulic circuit 7. In the hydraulic circuit 7, the bottom chamber 12 is arranged above and the head chamber 11 is arranged below, and the piston rod 23 is arranged on the foundation 127a of the structure 127.
A hydraulic pump 30 is connected to the head chamber 11 of the hydraulic cylinder 5 attached to the. The hydraulic pump 30 is driven by the electric motor 8 and sucks and discharges the oil in the oil tank 13. The hydraulic pump 30 passes through the check valve 33 and the flow meter 34 provided in the first pipe 32, and then the head port 11a.
It is connected to the. The first pipe 32 is branched between the hydraulic pump 30 and the check valve 33 to form a second pipe 35, and the first pipe 32 is branched between the check valve 33 and a flow meter 34 to provide a third pipe 36. There is. An ascending electromagnetic servo valve 37 is provided in the second pipe 35, and a descending electromagnetic servo valve 38 is provided in the third pipe 36. The ascending electromagnetic servo valve 37 and the descending electromagnetic servo valve 38 are provided. The return oil is returned to the oil tank 13.

A pressure / oil temperature sensor 39 is connected to the flow meter 34, and the flow meter 34 measures the flow rate of the working oil flowing inside, and at the same time, the pressure and oil temperature acting on the head chamber 11 of the hydraulic cylinder 5 are measured. Is measured by the pressure / oil temperature sensor 39 and transmitted to the controller 40 such as a controller. The control unit 40 receives the flow rate signal, the pressure signal and the oil temperature signal from the flow meter 34 and the pressure / oil temperature sensor 39 so that the ascending / descending speed of the hydraulic elevator 1 falls within a predetermined range. A command signal is output to the descending electromagnetic servo valve 38. Further, the control unit 40 is connected to a rising switch and a lowering switch (not shown), and receives the signals thereof to raise the electromagnetic servo valve 37 and the electromagnetic servo valve 38 for lowering.
The command signal is output to. The ascending electromagnetic servo valve 37 and the descending electromagnetic servo valve 38 are controlled so that the flow rate becomes constant by strengthening the throttle when the hydraulic pressure and the oil temperature are high. Further, the hydraulic circuit 7 includes a head port 11 a and a flow meter 34.
A switching valve 42 for manual operation is provided in the fourth pipe 41 that is branched between and to control and lower the speed in an emergency when the lifting and lowering is stopped. Further, the hydraulic circuit 7 is provided with a relief valve 43 so that abnormal pressure does not occur on the discharge side of the hydraulic pump 30.

Next, the operation of the hydraulic elevator 1 will be described. When the hydraulic elevator 1 moves up, a lift switch (not shown) is pressed. In response to this rising signal, the electric motor 8 rotates to rotate the hydraulic pump 30, and the control unit 40 outputs a command signal to the rising electromagnetic servo valve 37 to switch to the rising position (a). The pressure oil from the hydraulic pump 30 opens the check valve 33, enters the head port 11a via the flow meter 34, and is further supplied to the head chamber 11 of the hydraulic cylinder 5 from the passage hole 26 of the piston rod 23. Shrink. As the hydraulic cylinder 5 shrinks, the sheave 125 lowers the first pulley 123 of the pulley 3 and the car 131 rises. At this time, when the weight WL loaded on the car 131 is large, the hydraulic pressure acting on the head chamber 11 of the hydraulic cylinder 5 becomes high, and the hydraulic pressure at the flow meter 34 also becomes high. Flow meter 34
The high pressure oil at is measured by the pressure / oil temperature sensor 39, and the signal is transmitted to the control unit 40. Control unit 40
Receives the pressure signal, maintains the electromagnetic servo valve 37 for raising in the raised position (a), and supplies the entire discharge amount of the hydraulic pump 30 to the head chamber 11 of the hydraulic cylinder 5. As a result, the hydraulic elevator 1 moves up within a predetermined speed range.

When the weight WL loaded on the car 131 is small, the hydraulic pressure acting on the head chamber 11 of the hydraulic cylinder 5 becomes low, and the hydraulic pressure flowing through the flowmeter 34 also becomes low. The low oil pressure in the flow meter 34 is measured by the pressure / oil temperature sensor 39, and the signal is transmitted to the control unit 40. Control unit 40
Determines that the volumetric efficiency is additionally discharged from the hydraulic pump 30 in accordance with the low hydraulic pressure, and the electromagnetic solenoid valve for raising 37 is kept at the throttle rising position (b), and the extra discharge amount from the hydraulic pump 30 is determined. From the ascending position (b) to the oil tank 13
To the head chamber 11 of the hydraulic cylinder 5.
Supply to. As a result, the hydraulic elevator 1 moves up within a predetermined speed range. Similarly, regarding the oil temperature, when the temperature is low, an extra discharge amount corresponding to the volumetric efficiency is returned to the oil tank 13 from the throttle rising position (b), and the remaining discharge amount is supplied to the head chamber 11 of the hydraulic cylinder 5. The elevator 1 is raised within a predetermined speed range.

When the hydraulic elevator descends, a descending switch (not shown) is pressed. The control unit 40 receives the descending signal and outputs a command signal to the descending electromagnetic servo valve 38 to switch to the descending position (C). At this time, the control unit 40
The head chamber 11 through the flow meter 34, as in the case of rising.
A command signal is output to the descending electromagnetic servo valve 38 so that the car 131 descends at a predetermined speed in accordance with the oil pressure and the oil temperature at. The lowering electromagnetic servo valve 38 controls the return oil amount of the head 11 of the hydraulic cylinder 5 by moving the spool to a predetermined throttle position according to a command from the control unit 40 at the lowering position (C). This return oil amount is measured by the flow meter 34, and the control unit 40 outputs a correction command signal to the lowering electromagnetic servo valve 38 so as to enter a predetermined flow rate. As a result, the car 131 descends at a predetermined speed. Although the car 131 is lowered at a predetermined speed according to the oil pressure and the oil temperature in the above, either the oil pressure or the oil temperature which has a great influence may be used. When an abnormality occurs in the hydraulic cylinder 5 during the above-mentioned raising / lowering and the raising / lowering speed changes, the hydraulic cylinder 5 is moved at that position.
After the cylinder cover 18 is removed, the cylinder tube 17 is pulled down or the piston 20 is pulled up in that state, so that the hydraulic cylinder 5 is at the installed position and the piston seal ring 28 and / or the wear ring 29. Alternatively, the rod packing 24 can be inspected and replaced.

Next, a second embodiment of the hydraulic elevator will be described with reference to FIGS. 2 is an overall configuration diagram of a first hydraulic elevator 1A according to the second embodiment, and FIG. 3 is a side sectional view of a first hydraulic cylinder 5A. The same parts as those of the conventional example and the first embodiment are designated by the same reference numerals and the description thereof will be omitted. In the hydraulic elevator 1 of the first embodiment,
The weight WB of the balance weight 124 is the added weight WA of the own weight WC of the car 131 and the weight WL loaded on the car 131.
Is set to be larger than half (1/2) so that hydraulic pressure is constantly generated in the head chamber 11 of the hydraulic cylinder 5, and the car 131 is moved up and down by supplying and discharging the pressure oil in the head chamber 11. . On the other hand, in the first hydraulic elevator 1A of the second embodiment, the weight WB of the balance weight 124 is
Is set to be twice the weight WC of the car 131 and the added weight WA of the load WL loaded on the car 131, and the pressure oil acting on the first hydraulic cylinder 5A at that time is set to almost zero. ing. The reason why the pressure oil is set to almost zero is that the friction of pulleys, ropes, etc. is omitted. An extension chamber 45 and a reduction chamber 46 are provided in the first hydraulic cylinder 5A, and the car 131 is moved up and down by supplying and discharging pressure oil, thereby obtaining an energy saving effect as compared with the first embodiment.

In FIG. 3, first, the first hydraulic cylinder 5A of the first hydraulic elevator 1A will be described. First
The hydraulic cylinder 5A mainly includes the bottom chamber 12 and the extension chamber 45.
And a reduction chamber 46. The extension chamber 45 is connected to the extension port 45a, and the reduction chamber 46 is connected to the first hydraulic circuit 7A shown in FIG. 2 via the reduction port 46a. The first hydraulic cylinder 5A includes a first cylinder tube portion 14A and a first piston portion 15A.
In the first cylinder tube portion 14A, a first cylinder tube 47 is formed by a hollow tube, and the first cylinder tube 47 is provided with the bottom chamber 12 above the drawing. The bottom chamber 12 includes the inner diameter 47a of the first cylinder tube 47, the lower surface of the first bottom cover 18A, and the first bottom cover 18A.
It is formed by the upper surface of the piston 48. The first bottom cover 18A is detachably screwed to the first cylinder tube 47 with a screw 49.

The first bottom cover 18A includes a rod 50.
One end surface of the rod 5 is attached by a bolt 51, and the rod 5
The other end surface 50a of 0 penetrates the hole 48a of the first piston 48, is located in the extension chamber 45 formed in the first piston 48, and receives the hydraulic pressure acting in the extension chamber 45. The hydraulic pressure acting in the extension chamber 45 acts on the other end surface 50a of the rod 50 to push the first bottom cover 18A upward in the drawing to extend the first hydraulic cylinder 5A. A seal 52 is provided in the hole 48a of the first piston 48 to prevent the pressure oil acting in the extension chamber 45 from leaking to the bottom chamber 12.
Is provided.

Below the first cylinder tube 47 in the drawing,
The inner diameter surface 47a of the first cylinder tube 47, the outer diameter surface 53a of the first piston rod 53, and the first cylinder head 47.
A reduction chamber 46 is formed between the same and b. A first piston rod 53 penetrates the first hole 47d of the first cylinder head 47b, and the first piston rod 53 slidably supports the first cylinder tube 47. The first hole 47d of the first cylinder head 47b is provided with a first rod packing 54 that abuts the first piston rod 53 and seals the pressure oil in the reduction chamber 46. Or the first
Although not shown, the cylinder head 47b may be provided with a head cover of a normal structure so as to be detachable with bolts, and a bush, a cylinder seal, a gland, and an O-ring may be assembled to seal the pressure oil in the reduction chamber 46.

The first piston portion 15A is the first piston 4
8 is inserted into the inner diameter 47 a of the first cylinder tube 47 in a concentric manner. A piston seal ring 28 and a wear ring 29 are provided between the first piston 48 and the first cylinder tube 47. The first piston 48 is pivotally inserted into the first cylinder tube 47, and the piston seal ring 28 transfers the pressure oil in the reduction chamber 46 to the bottom chamber 12.
The wear ring 29 receives the thrust load so that the wear ring 29 does not leak. As a result, the first hydraulic cylinder 5A
Seals the pressure oil with the first piston 48,
First cylinder tube 17A with respect to first piston 48
Is stretchable by being slidable in the vertical direction in the figure. The first piston 48 is integrally formed with a first piston rod 53 formed of a hollow pipe, and the first piston rod 53 is provided with hydraulic oil from the reduction port 46a.
A first passage hole 55 for supplying and discharging to and from 6 is opened. The first piston rod 53 has one end side fixed to the first piston 48 by welding, and the other end side screwed to the piston tip member 57 by a screw 56. An O-ring 58 is provided between the first piston 48 and the piston tip member 57 to prevent the hydraulic oil from the reduction port 46a from leaking to the outside.

Inside the first piston rod 53, a hollow pipe 59 is arranged between the first piston 48 and the piston tip member 57. The inner diameter surface 53b of the first piston rod 53 and the outer diameter surface 59a of the hollow pipe 59 form the passage 6
0 is formed, and the reduction port 46a and the reduction chamber 46 are connected by the first passage hole 55 and the passage 60 to form a passage for hydraulic oil. An O-ring 61 is disposed between the hollow pipe 59 and the piston tip member 57, and the O-ring 61 is provided.
0 and the extension chamber 45 are prevented from leaking pressure oil. The piston tip member 57 is screwed onto the first piston rod 53 in the upper part of the drawing to be integrally connected thereto, and the lower end part 57a of the lower part is detachably attached to the foundation 127a of the structure 127 by a bolt or the like not shown. It is worn. The piston tip member 57 has an extension port 45 connected to the extension chamber 45.
a is also a reduction port 46a connected to the reduction chamber 46.
Is provided, and the expansion port 45a and the contraction port 46a are connected to the first hydraulic circuit 7A. In the first hydraulic cylinder 5A having the above structure, the total length La of the first cylinder tube 47A is the same as the first cylinder tube 47A.
Is formed shorter than the slidable length Lo of the first piston rod 53 that is slidably inserted into. The slidable length Lo of the first piston rod 53 is set, for example, in a range in which the first cylinder head 47b does not overlap the welded portion of the first piston rod 53 and the first piston 48 as shown in FIG. .

With the above structure, the same effect as that of the first embodiment can be obtained. That is, when the first cylinder tube 47 is lowered as shown by the chain double-dashed line Tp, the first piston 48 projects from the upper surface 47e of the first cylinder tube 47, so that the piston used for the first piston 48 Inspection of the seal ring 28 and / or the wear ring 29,
It can be replaced easily and serviceability is improved. Particularly, in the first hydraulic cylinder 5A, after the first cylinder cover 18A is removed, the first cylinder tube 17A is pulled down in that state, so that the first piston rod 53 is left as it is at the installed position. Piston seal ring 28 and / or wear ring 2
9 can be inspected and replaced. The first rod packing 54 is inspected and replaced by first removing the first bottom cover 18A from the first cylinder tube 47 and rotating it by using the bolt hole 48b provided in the first piston 48 to rotate the piston tip member 57. And the first piston rod 5
The screwing of the three screws 56 is separated. After this, the first piston 48 is pulled up until the lower end portion 53d of the first piston rod 53 in the figure is located above the inside of the first cylinder head 47b. As a result, the first rod packing 54 can be easily inserted into the first cylinder head 47b from the lower side in the drawing at the installed position and can be replaced. Alternatively, the outer diameter surfaces of the first piston rod 53 and the piston tip member 57 are formed to be the same, and the piston tip member 57 is fixed to the foundation 127a via the pin 24 and the bracket 25 as in the first embodiment. Therefore, as in the first embodiment, the first rod packing 54 can be inspected and replaced. As described above, the piston seal ring 28 and / or the wear ring 29, or the first ring
In order to inspect and replace the rod packing 54, it is not necessary to carry out the first hydraulic cylinder 5A from a narrow place, and the maintainability is remarkably improved. The first hydraulic cylinder 5A is supplied with hydraulic oil to the extension chamber 45 from a hydraulic source such as a bidirectional rotary hydraulic pump / motor 65 (hereinafter referred to as pump / motor 65) of a first hydraulic circuit 7A described later. To extend. Further, the first hydraulic cylinder 5A can be reduced by supplying hydraulic oil to the reduction chamber 46 from a hydraulic source such as a pump / motor 65.

The first hydraulic circuit 7A is provided with an extension chamber 45 and a reduction chamber 46, and also has a first piston rod 53.
Is attached to the foundation 127a of the structure 127, the extension port 45a and the contraction port 4 of the first hydraulic cylinder 5A.
6a. The pump / motor 65 is rotationally driven in both directions by an inverter-controlled electric motor 66, and mainly supplies and discharges hydraulic oil between the extension chamber 45 and the reduction chamber 46, so that the first
The hydraulic cylinder 5A is expanding and contracting. The inverter control electric motor 66 drives the pump / motor 65 according to the loaded weight WL, which will be described later in detail.
Alternatively, braking is performed. In the pump / motor 65, one port 65a is connected to the extension port 45a through the fifth pipe 67, and the other port 65b is connected to the first hydraulic cylinder 5A through the sixth pipe 68.
A check valve 69 with extension pilot for the fifth pipe 67
(Hereinafter, the check valve 69 for extension) is the sixth
A check valve 70 with a reducing pilot (hereinafter referred to as a reducing check valve 70) is arranged in the pipe 68.

The extension check valve 69 and the contraction check valve 70 are connected to the pilot pressure electromagnetic switching valve 74 by the first pilot pipe 71 and the second pilot pipe 72, and receive the pilot pressure control signal. First
The pilot pressure Ps of the pilot pipe 71 is a signal for closing the extension check valve 69 and the reduction check valve 70, and the pilot pressure Po of the second pilot pipe 72 is a signal for opening the extension check valve 69 and the reduction check valve 70. Is being output. The pilot pressure solenoid operated directional control valve 74 is connected to the third pilot pipe 75, and one third pilot pipe 75 is connected to the extension upstream side check valve 76 and the extension downstream side check valve 77. Received as pilot pressure. Further, the other third pilot pipe 75 is connected to the reduction upstream check valve 78 and the reduction downstream check valve 79, and receives the higher hydraulic pressure to make the pilot pressure. That is, the third pilot pipe 75 is connected to the fifth pipe 67 and the sixth pipe 68 via the check valves 76, 77, 78, 79 arranged in the third pilot pipe 75, respectively, and the highest pressure is obtained. Solenoid switching valve 74 for pilot pressure as pilot pressure
Is being supplied to.

When the first hydraulic elevator 1A is stopped,
A signal for closing the expansion check valve 69 and the contraction check valve 70 in response to the higher hydraulic pressure of the expansion downstream side check valve 77 or the contraction downstream side check valve 79 when the pilot pressure electromagnetic switching valve 74 is in the position (e). Is being output.
As a result, in the first hydraulic cylinder 5A, leakage from the extension check valve 69 and the contraction check valve 70 is prevented, and the fall of the car 131 can be reduced. First
When the hydraulic elevator 1A moves up and down, the pilot pressure electromagnetic switching valve 74 switches to the position (f), and the extension upstream side check valve 76, the extension downstream side check valve 77, the reduction upstream side check valve 78, and the reduction downstream side check valve 79. In response to the highest hydraulic pressure, the expansion check valve 69 and the contraction check valve 70 output an open signal. As a result, the extension check valve 69 and the contraction check valve 70 open, and the first check valve 69 and the contraction check valve 70 open.
The return oil can flow from the hydraulic cylinder 5A to the pump / motor 65, and the first hydraulic cylinder 5A expands and contracts to lift and lower the first hydraulic elevator 1A.

On both sides of the pump / motor 65 and in the fifth
An oil amount device 80 for charging is provided in the pipe 67 and the sixth pipe 68.
Is provided. The charging oil amount device 80 includes a charging hydraulic pump 80a, a charging electric motor 80b,
Second relief valve 80c, charge check valve 80d,
It is formed by the oil tank 13 and prevents the occurrence of cavitation in the first hydraulic circuit 7A. Also, the pump
Relief valves 43 are provided on both sides of the motor 65 and in the fifth pipe 67 and the sixth pipe 68 so as to prevent abnormal pressure from occurring via the relief valve check valve 43a.
Further, between the extension check valve 69 and the extension port 45a, a manual operation pump device 82 for controlling the speed and lowering it in an emergency where the lifting and lowering is stopped is provided. The manual operation pump device 82 includes a manual pump 82a,
Check valve 82b for manual operation, relief valve 8 for manual operation
2c, an oil tank 13.

In the vicinity of the expansion port 45a and the contraction port 46a, a solenoid-operated check valve 84 for descending, which elevates and lowers while controlling the speed by the throttle 83 in an emergency where the elevator stops, and an ascending valve. An electromagnetic check valve 85 is provided. As will be described later, the electromagnetic check valve for lowering 84 has a load weight on the car 131 of the allowable load weight WL /
When the number exceeds 2, the hydraulic pressure generated in the reduction chamber 46 of the first hydraulic cylinder 5A is returned to the oil tank 13 to extend the first hydraulic cylinder 5A and lower the car 131. Further, the solenoid-operated check valve 85 for ascending returns the hydraulic pressure generated in the extension chamber 45 of the first hydraulic cylinder 5A to the oil tank 13 when the weight loaded on the car 131 is equal to or less than the allowable weight WL / 2. The first hydraulic cylinder 5A is reduced and the car 131 is raised to stop at a predetermined number of floors.

Next, the operation of the first hydraulic elevator 1A will be described. The first hydraulic elevator 1A is a car 1
When the weight to be loaded on 31 is equal to or less than the allowable load weight WL / 2, the weight WB of the balance weight 124 causes the first load
Hydraulic pressure acts on the extension chamber 45 of the hydraulic cylinder 5A.
On the contrary, when the load weight on the car 131 exceeds WL / 2 of the allowable load weight, the balance weight 1
Since the added value of the own weight WC of the car 131 and the loaded weight WL / 2 becomes larger than the weight WB 24 of 24, the hydraulic pressure acts on the reduction chamber 46 of the first hydraulic cylinder 5A. When the first hydraulic elevator 1A is stopped and the loaded weight exceeds WL / 2, the oil pressure in the reduction chamber 46 passes through the positions (e) of the reduction downstream check valve 79 and the pilot pressure electromagnetic switching valve 74, and When the loaded weight is less than WL / 2, the hydraulic pressure in the extension chamber 45 passes through the positions (e) of the extension downstream check valve 77 and the pilot pressure electromagnetic switching valve 74, and then the extension check valve 69 and the reduction check valve 70 are set. It acts in the closing direction to prevent leakage.

Next, when the first hydraulic elevator 1A moves up, a lift switch (not shown) is pressed. In response to this rising signal, the inverter control electric motor 66 rotates to rotate the pump / motor 65, and at the same time, outputs a command to the pilot pressure electromagnetic switching valve 74 to switch to the position (f). Since the ascending is performed by reducing the first hydraulic cylinder 5A, it is necessary to supply the working oil to the reducing chamber 46 and to return the working oil of the extending chamber 45. At this time, when the loaded weight exceeds WL / 2, the reduction chamber 4
Since the hydraulic pressure is generated in 6, the hydraulic pressure of the reduction chamber 46 initially passes through the reduction downstream side check valve 79 and the pilot pressure electromagnetic switching valve 74 (to), and then the extension check valve 69 and the reduction check valve 70 are operated. It acts in the opening direction.

Next, the pump / motor 65 is driven by the inverter control electric motor 66 to discharge the pressure oil to reduce the upstream side check valve 78 and the pilot pressure electromagnetic switching valve 74.
The check valve 69 for extension and the check valve 70 for contraction are actuated in the opening direction via the position (to). The pressure oil discharged from the pump / motor 65 passes through the reduction check valve 70, the reduction port 46 a, and the first passage hole 55, and then the reduction chamber 4
6, the hydraulic pressure of the balance weight 124 can be reduced, and the hydraulic pressure of the pump action of the pump / motor 65 can be added to reduce the pressure, and the first hydraulic elevator 1A can be raised by energy saving. . Further, the return hydraulic oil from the extension chamber 45 is supplied to the pump / motor 65 through the opened extension check valve 69. As a result, in the first hydraulic elevator 1A, the discharge oil amount by the pump action of the pump / motor 65 is controlled by the constant rotation speed driven by the inverter control electric motor 66, and a predetermined speed is obtained. At this time, when the working oil supplied from the expansion chamber 45 is insufficient, the charging oil amount device 80 supplies the working oil to the fifth pipe 67.

Further, when the load is WL / 2 or less at the time of rising, the oil pressure is generated in the extension chamber 45, so that the oil pressure in the extension chamber 45 is at the positions of the extension downstream check valve 77 and the pilot pressure electromagnetic switching valve 74. After (), the extension check valve 69 and the contraction check valve 70 act in the opening direction. The pressure oil generated in the extension chamber 45 is transferred to the extension port 45.
a, acting on the pump / motor 65 via the extension check valve 69 to rotate the pump / motor 65 as a motor. The rotation of the pump / motor 65 rotates at a constant rotation speed while being braked by the inverter control electric motor 66. The pump / motor 65 that rotates as this motor enters the reduction chamber 46 via the reduction check valve 70, the reduction port 46 a, and the first passage hole 55. At this time, the return hydraulic pressure of the extension chamber 45 generated by the weight WB of the balance weight 124 causes the pump / motor 65 to rotate as a motor. Therefore, the braking force of the pump / motor 65 is required, but the driving force is not required, and the energy saving contributes to One hydraulic elevator 1A can be raised. As a result, the first hydraulic elevator 1A obtains a predetermined speed by controlling the amount of return oil due to the motor action of the pump / motor 65 at a constant rotation speed braked by the inverter control electric motor 66. At this time, if the hydraulic oil entering the reduction chamber 46 is insufficient, the charging oil amount device 80 to the sixth pipe 68
Is supplied to.

Next, when the hydraulic elevator descends, a descending switch (not shown) is pressed. In response to this descending signal, the inverter control motor 66 rotates and the pump
While rotating the motor 65, a command is output to the pilot pressure electromagnetic switching valve 74 to switch to the position (f). Since the descent is performed by extending the first hydraulic cylinder 5A, it is necessary to supply hydraulic oil to the expansion chamber 45 and return hydraulic oil to the reduction chamber 46. At this time, since the hydraulic pressure is generated in the reduction chamber 46 when the loaded weight exceeds WL / 2, the hydraulic pressure in the reduction chamber 46 is reduced to the position of the reduction downstream side check valve 79 and the pilot pressure electromagnetic switching valve 74. After that, the check valve for expansion 69 and the check valve for contraction 70 act in the opening direction.

The pressure oil generated in the reduction chamber 46 due to the load amount exceeding WL / 2 is applied to the first passage hole 55 and the reduction port 4.
6a and the reduction check valve 70 to act on the pump motor 65 to rotate the pump motor 65 as a motor. The rotation of the pump / motor 65 rotates at a predetermined rotation speed while being braked by the inverter control electric motor 66. The pump / motor 65 that rotates as this motor enters the extension chamber 46 via the extension check valve 69 and the extension port 45a. As a result, the weight WC of the car 131 is 2
Since the pump / motor 65 is rotated as a motor by the return hydraulic pressure due to the doubled weight and the added weight WA of the loaded weight WL to the car 131, the braking force of the pump / motor 65 is required, but the driving force is not required and the energy saving is One hydraulic elevator 1A can be raised. As a result, the first hydraulic elevator 1A has the pump / motor 65
Of the amount of oil returned by the motor action of the inverter-controlled motor 6
A predetermined speed is obtained by being controlled by a constant rotation speed braked by 6. At this time, if the hydraulic oil to the extension chamber 45 is insufficient, the charging oil amount device 80 moves the
It is supplied to the pipe 67.

Further, when the loaded weight is less than WL / 2 when descending, since the hydraulic pressure is generated in the extension chamber 45, the extension chamber 4
The hydraulic pressure of 5 acts in a direction of opening the extension check valve 69 and the contraction check valve 70 via the positions (to) of the extension downstream check valve 77 and the pilot pressure electromagnetic switching valve 74. Next, the inverter control motor 66 pumps
The motor 65 is driven to discharge the pressure oil, and the expansion check valve 69 and the contraction check valve 70 act in the opening direction through the positions (to) of the expansion upstream side check valve 76 and the pilot pressure electromagnetic switching valve 74. . The pressure oil discharged from the pump / motor 65 enters the extension chamber 45 through the extension check valve 69 and the extension port 45a, and is reduced by the hydraulic pressure due to the weight WB of the balance weight 124. It is only necessary to add the amount of pressure oil discharged by the pumping action to the first hydraulic elevator 1A by energy saving. Also, reduction chamber 4
The return hydraulic fluid from 6 is supplied to the pump motor 65 via the reduction check valve 70 which is opened. As a result, in the first hydraulic elevator 1A, the discharge oil amount by the pump action of the pump / motor 65 is controlled by the constant rotation speed driven by the inverter control electric motor 66, and a predetermined speed is obtained. At this time, if the working oil from the reduction chamber 46 is insufficient, it is supplied from the charging oil amount device 80 to the sixth pipe 68. When an abnormality occurs in the first hydraulic cylinder 5A and the ascending / descending speed changes during the above-described ascending / descending, after removing the first cylinder cover 18A of the first hydraulic cylinder 5A at that position, the first hydraulic cylinder 5A is left in that state as it is. By pulling down the cylinder tube 47 or pulling up the first piston 48, the first hydraulic cylinder 5A is at the installed position, and the piston seal ring 28 and / or the wear ring 29 or the first rod packing 5 is provided.
4. Inspection and replacement can be done.

In the second embodiment, the weight WB of the balance weight 124 is twice the weight WC of the car 131, and the added weight WA of the weight WL loaded on the car 131.
The first hydraulic cylinder 5A at that time
The pressure oil that acts on the
In the hydraulic cylinder 5A, as in the first embodiment, the weight WB of the balance weight 124 is the weight W of the car 131.
It may be set to be larger than half (1/2) of the added weight WA of the loading weight WL on the C and the car 131,
Alternatively, the hydraulic pressure may be generated in the extension chamber or the reduction chamber by reducing the pressure. Further, although the fixed pulley and the moving pulley are configured as one piece, other numbers of fixed pulleys and moving pulleys may be used. At that time, the weight WB of the balance weight 124 and the car 131 are adjusted accordingly.
It is sufficient to set the ratio of the own weight WC of the above and the added weight WA of the weight WL loaded on the car 131. Although the hydraulic jack 1 of the present invention has been described for a hydraulic elevator, it goes without saying that it can be used for other hydraulic cargo handling machines.

[0045]

As described above, when the hydraulic cylinder of the present invention is used in a hydraulic elevator, the tip end portion of the piston rod housed in the cylinder tube is attached to the foundation of the hoistway, and A bottom cover is detachably attached to the upper end of the cylinder tube. As a result, the cylinder tube can be moved downward by removing the bottom cover, the piston can be projected from the upper end surface of the cylinder tube, and the packing, seal ring, or thrust bearing attached to the piston does not move the piston rod. Can be easily replaced with the foundation attached. Or, with the piston rod attached to the foundation,
The piston can be taken out of the cylinder tube, and the packing, seal ring, or thrust bearing,
Alternatively, the replacement of the rod packing can be facilitated.
By using this hydraulic cylinder in a hydraulic elevator, the hydraulic circuit of the hydraulic elevator can be easily maintained.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a hydraulic elevator according to a first embodiment of the present invention.

FIG. 2 is an overall configuration diagram of a hydraulic elevator according to a second embodiment of the present invention.

FIG. 3 is a side sectional view of a hydraulic cylinder of a second embodiment according to the present invention.

FIG. 4 is a diagram illustrating a conventional hydraulic elevator.

FIG. 5 is an overall configuration diagram illustrating another conventional hydraulic elevator.

FIG. 6 is a partial side sectional view of a hydraulic cylinder used in another conventional hydraulic elevator.

[Explanation of symbols]

1, 1A ... Hydraulic elevator, 3 ... Pulley part, 5, 5A ...
Hydraulic cylinder, 7, 7A ... Hydraulic circuit 11 ... Head chamber, 1
2 ... Bottom chamber, 13 ... Oil tank, 14, 14A ... Cylinder tube part, 15, 15A ... Piston part, 17, 47
… Cylinder tube, 18, 18A… Bottom cover, 2
0, 48 ... Piston, 23, 53 ... Piston rod, 2
4, 54 ... Rod packing, 28 ... Piston seal ring, 29 ... Bearing metal (wafer ring), 30 ... Fixed displacement hydraulic pump, 33 ... Check valve, 34 ... Flowmeter,
37 ... electromagnetic servo valve for raising, 38 ... electromagnetic servo valve for lowering, 39 ... pressure / oil temperature sensor, 40 ... control unit, 45 ... extension chamber, 46 ... reduction chamber, 50 ... rod, 57 ... piston tip member, 65 … Bi-directional rotary hydraulic pump / motor, 66
... Inverter control motor, 69 ... Check valve with extension pilot, 70 ... Check valve with reduction pilot, 74
... electromagnetic switching valve for pilot pressure, 76 ... extension upstream check valve, 77 ... extension downstream check valve, 78 ... extension downstream check valve, 79 ... reduction downstream check valve, 124 ... balance weight 127a ... foundation, 131 ... Loading basket.

[Procedure amendment]

[Submission date] July 27, 2001 (2001.7.2)
7)

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] Claim 2

[Correction method] Change

[Correction content]

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0014

[Correction method] Change

[Correction content]

In the hydraulic elevator 1 of the first embodiment, the pulley 3 includes a first pulley 123, a balance weight 124, a sheave 125, a rope 128, and a second pulley 12.
9. The balance weight 124, which is formed by the third pulley 130, offsets the total weight of the car 131 and the load on which the car 131 is mounted to some extent when the car is lifted, so that the energy saving effect of the electric motor 8 as a drive source is obtained. To be The weight WB of the balance weight 124 is 1
It is set to about 70% of 31's own weight WC . For example,
The weight WB of the balance weight 124 is [WB≈0.7
X WC x (number of moving pulleys + 1)]
It In the case of the above example of FIG. 1, WB≈0.7 × WC × 2
Is set to. Balance weight of 124
The weight WB is at least lower than the own weight WC of the car 131.
It is a good value, and a basket that saves energy as much as possible 1
It is arranged close to the own weight WC of 31. this
In the case of the hydraulic elevator 1, the balance weight 12
The weight WB of 4 constantly generates hydraulic pressure in the head chamber 11 of the hydraulic cylinder 5.

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0017

[Correction method] Change

[Correction content]

In the piston portion 15, the piston 20 is pivotally inserted into the inner diameter surface 17a of the cylinder tube 17. A piston rod 23 is formed integrally with the piston 20, and the head chamber 1 is provided inside the piston rod 23.
1 and a passage hole 26 connecting to the head port 11a. The piston rod 23 is attached to the cylinder head 17
with penetrating b of hole 21, the tip portion 23a of the lower side in the figure, via a pin 25 extending through the distal end portion 23a Bed
It is attached to the racket 25b . Pin 25 is nut 2
It is fixed to the bracket 25b by 5a . Braque
The cap 25b is attached to the foundation 127a of the structure 127 by an anchor bolt or the like (not shown). For inspection and replacement of the rod packing 24, first, the bottom cover 18 is removed from the cylinder tube 17, and the pin 25 is pulled out from the tip portion 23a of the piston rod 23. After that,
The piston 20 is pulled up until the lower end portion 23a of the piston rod 23 shown in the figure is located above the inside of the cylinder head 17b. As a result, the rod packing 24 can be easily inserted into the hole 21 of the cylinder head 17b from the lower side in the drawing at the installed position and can be replaced. Alternatively, the piston 20 and the piston rod 23 may be configured separately as shown by the chain double-dashed line, and formed by a nut 27 so that only the piston 20 can be taken out above the cylinder tube 17.

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

[Correction content]

Next, a second embodiment of the hydraulic elevator will be described with reference to FIGS. 2 is an overall configuration diagram of a first hydraulic elevator 1A according to the second embodiment, and FIG. 3 is a side sectional view of a first hydraulic cylinder 5A. The same parts as those of the conventional example and the first embodiment are designated by the same reference numerals and the description thereof will be omitted. In the hydraulic elevator 1 of the first embodiment,
The weight WB of the balance weight 124 is set to be about 70% of the own weight WC of the car 131, and the hydraulic cylinder 5
A hydraulic pressure is constantly generated in the head chamber 11, and the car 131 is moved up and down by supplying and discharging the pressure oil in the head chamber 11.
On the other hand, the first hydraulic elevator 1 of the second embodiment
In A, the weight WB of the balance weight 124 is 1
Twice the self-weight WC of 31 and the weight W loaded on the car 131
It is set so that the additional weight WA of L becomes, and at that time,
The pressure oil acting on the hydraulic cylinder 5A is set to be substantially zero. In addition, it is said that the pressure oil becomes almost zero,
This is because friction such as pulleys and ropes is omitted. An extension chamber 45 and a reduction chamber 46 are provided in the first hydraulic cylinder 5A, and the car 131 is moved up and down by supplying and discharging pressure oil, thereby obtaining an energy saving effect as compared with the first embodiment.

[Procedure Amendment 5]

[Document name to be amended] Statement

[Correction target item name] 0031

[Correction method] Change

[Correction content]

With the above structure, the same effect as that of the first embodiment can be obtained. That is, when the first cylinder tube 47 is lowered as shown by the chain double-dashed line Tp, the first piston 48 projects from the upper surface 47e of the first cylinder tube 47, so that the piston used for the first piston 48 Inspection of the seal ring 28 and / or the wear ring 29,
It can be replaced easily and serviceability is improved. Particularly, in the first hydraulic cylinder 5A, after the first cylinder cover 18A is removed, the first cylinder tube 17A is pulled down in that state, so that the first piston rod 53 is left as it is at the installed position. Piston seal ring 28 and / or wear ring 2
9 can be inspected and replaced. The first rod packing 54 is inspected and replaced by first removing the first bottom cover 18A from the first cylinder tube 47 and rotating it by using the bolt hole 48b provided in the first piston 48 to rotate the piston tip member 57. And the first piston rod 5
The screwing of the three screws 56 is separated. After this, the first piston 48 is pulled up until the lower end portion 53d of the first piston rod 53 in the figure is located above the inside of the first cylinder head 47b. As a result, the first rod packing 54 can be easily inserted into the first cylinder head 47b from the lower side in the drawing at the installed position and can be replaced. Alternatively, the outer diameter surfaces of the first piston rod 53 and the piston tip member 57 are formed to be the same, and the piston tip member 57 is fixed to the foundation 127a via the pin 25 and the bracket 25b as in the first embodiment. Therefore, similar to the first embodiment, the first rod packing 54
Can be inspected and replaced. As described above, the inspection and replacement of the piston seal ring 28 and / or the wear ring 29 or the first rod packing 54 does not require the first hydraulic cylinder 5A to be carried out from a narrow place, and the maintainability is significantly improved. To do. The above-mentioned first hydraulic cylinder 5A is
The expansion chamber 45 is expanded by being supplied with hydraulic oil from a hydraulic source such as a bidirectional rotary hydraulic pump / motor 65 (hereinafter, referred to as pump / motor 65) of the first hydraulic circuit 7A, which will be described later. Further, the first hydraulic cylinder 5A can be reduced by supplying hydraulic oil to the reduction chamber 46 from a hydraulic source such as a pump / motor 65.

[Procedure correction 6]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

[Figure 1]

[Procedure Amendment 7]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) F15B 11/02 FF term (reference) 3F301 BA02 BB12 CA11 3H081 AA01 AA03 BB02 BB16 CC21 CC28 DD18 DD25 DD26 DD32 HH03 3H089 AA21 AA90 BB03 BB15 CC06 DA02 DA14 DB03 DB33 DB34 DB43 FF06 FF07 GG02 JJ10

Claims (7)

[Claims] 1. A hydraulic cylinder (5, 5) of a hydraulic elevator (1, 1A) for raising and lowering a person and / or a luggage-carrying basket.
5A), a piston (20, 48) that is inserted pivotally into the cylinder tube (17, 47) and seals the pressure oil.
A bottom cover (18, 18A) removably attached to the upper end of the cylinder tube, and a tip on one end side that penetrates the lower portion of the cylinder tube as a foundation (127
A hydraulic cylinder of a hydraulic elevator, characterized in that the hydraulic cylinder is attached to a) and comprises a piston rod (23, 53) provided with the piston at an upper portion on the other end side. 2. A hydraulic cylinder (5A) of a hydraulic elevator (1A) for raising and lowering a person and / or a luggage-carrying car, which is pivotally inserted into a cylinder tube (47),
A piston (48) for sealing pressure oil and a bottom cover (1) detachably attached to the upper end of the cylinder tube.
8A) and a tip portion on one end side that penetrates the lower portion of the cylinder tube is attached to the foundation (127a),
A piston rod (53) having the piston at the upper end on the other end side is attached to the cylinder tube at one end face side, penetrates the piston, and the other end face side is disposed inside the piston rod. Rod (50)
And a reduction chamber (45) provided on the lower side of the piston between the cylinder tube and the piston rod, and an extension chamber (46) formed by the rod inside the piston rod. And hydraulic cylinder. 3. The hydraulic cylinder for a hydraulic elevator according to claim 1, wherein the cylinder tube is removed after disassembling the bottom cover with the tip end on one end side attached to the foundation at the time of disassembly. To project the piston, or to take out the piston above the cylinder tube, and to pack the piston,
A hydraulic cylinder for a hydraulic elevator, characterized in that a seal ring or bearing metal can be replaced. 4. The hydraulic cylinder for a hydraulic elevator according to any one of claims 1 to 3, wherein a total length La of the cylinder tube is a slidable length of the piston rod slidably inserted in the cylinder tube. A hydraulic cylinder for a hydraulic elevator characterized by being shorter than Lo. 5. Hydraulic pressure of a hydraulic elevator (1) in which a balance weight (124) is attached to generate a lower hydraulic pressure than the hydraulic pressure for raising and lowering a luggage loading car (WC) to reduce the power of a drive source (8). In the circuit (7), at least a piston (20) that is inserted into the cylinder tube (17) in a pivotal manner and seals pressure oil, and a tip end on one end side that penetrates below the cylinder tube are mounted on a foundation (127a). A piston rod (23) provided with the piston at the upper end on the other end side, and an elevating chamber (11) provided between the cylinder tube and the piston rod on the lower side of the piston. A hydraulic cylinder (5) having the hydraulic cylinder (5) is provided, and when the hydraulic elevator is raised, the hydraulic oil of the fixed volume type hydraulic pump is supplied to the elevating chamber through a check valve and a flow meter. When the cylinder is extended and the hydraulic elevator is lowered, the electromagnetic servo valve for lowering provided on the downstream side of the check valve is operated to communicate the lifting chamber and the tank, and the hydraulic pressure in the lifting chamber and / or A hydraulic circuit using a hydraulic cylinder of a hydraulic elevator, characterized in that the hydraulic cylinder is reduced while controlling the flow rate discharged from the ascending / descending chamber by a flow meter or an electromagnetic servo valve for lowering according to the oil temperature. 6. A car (13) for carrying people and / or luggage
In the hydraulic circuit (7A) of the hydraulic elevator in which the hydraulic pressure of the hydraulic cylinder for raising and lowering 1) is lowered by attaching the balance weight (124), the power of the drive source is reduced, at least in the cylinder tube (47). The piston (48) that is inserted and seals the pressure oil, and the tip end on one end side that penetrates the lower portion of the cylinder tube are attached to the foundation (127a), and the piston is provided on the upper end portion on the other end side. A piston rod (53), one end surface side of which is attached to the cylinder tube and which penetrates the piston and the other end surface side of which is disposed inside the piston rod; A reduction chamber (46) provided between the cylinder tube and the piston rod on the lower side, and the rod inside the piston rod. A hydraulic cylinder (5A) having a formed extension chamber (45) is provided, and one side is connected to the reduction chamber via the reduction pilot check valve (70) and the other side is extended to the extension pilot check valve (). 6
9) and the drive source (6
6) A bidirectional rotary hydraulic pump / motor (65) driven by 6) and pilot pipes (75) connected upstream and downstream of the reduction pilot check valve and the extension pilot check valve, respectively. The check valves (76, 77, 78, 79) and the check pilot valve for reduction and the check valve with extension pilot, which receive the maximum pilot pressure of each check valve, output either a close command or an open command. A hydraulic circuit using a hydraulic cylinder of a hydraulic elevator, characterized in that the hydraulic circuit comprises a pilot pressure solenoid operated directional control valve (74). 7. The pilot pressure solenoid operated directional control valve (74) comprises:
7. The hydraulic cylinder for a hydraulic elevator according to claim 6, wherein the hydraulic elevator outputs a closing command to the reduction pilot check valve and the extension pilot check valve when stopped and an opening command when the elevator is moved up and down. The hydraulic circuit used.