JPH0133842Y2 - - Google Patents

Description

[Detailed explanation of the idea]

[Industrial Application Field] The present invention relates to an improvement in an energy-saving lifter used particularly for raising and lowering a heavy load. [Prior Art] Conventionally, a lifter as shown in FIG. 1 has been known. For example, a similar type of lifter is shown in Utility Model Application Publication No. 57-102, but this lifter has a weight load of 1
The head chamber 2a of the cylinder 2 for driving the cylinder 2 is connected to a tank 3 having the pressure necessary to maintain the increase in the weight load.
A small amount of compressed air is supplied to the rod chamber 2b while the piston 2c and the rod 2d are in communication with each other, or a small amount of compressed air is exhausted from the rod chamber 2b to connect the piston 2c and the rod 2d.
by lowering or raising the weight load 1
This is an energy-saving type that aims to reduce air consumption by driving the engine. Therefore, the above-mentioned lifter is required to have various functions such as intermediate deceleration, emergency stop, and inching in addition to constant-speed lifting and lowering, and for this reason, the above-mentioned lifter is equipped with a large number of valves. . That is, the rod side flow path 4 is provided with a drive pressure regulating valve 5 that determines the supply pressure to the rod chamber 2b, a drive valve 6 that controls the supply and discharge of compressed air in the rod chamber 2b, and the rod side flow path 4. An emergency stop valve 7 is connected to the head side flow path 9 to allow communication between the tank 3 and the rod chamber 2a. A speed change valve 13 that switches the flow path 11 to flow through the head side flow path 9 and an emergency stop valve 14 that cuts off the head side flow path 9 are connected, and a replenishment pressure reducing valve 17 is connected between the tank 3 and the air source 16. ing. Therefore, if the drive valve 6 is switched while the emergency stop valves 7 and 14 are turned on, the weight load 1 can be raised or lowered, and if the speed change valve 13 is switched in the middle of the raising or lowering operation, intermediate deceleration is achieved, and the emergency stop valve 7,
An emergency stop can be performed by switching 14 from on to off. Furthermore, inching can be performed by repeatedly turning on and off the emergency stop valves 7 and 14. However, the above-mentioned lifter not only requires many types of valves, but also has a plurality of valves connected in series to the main flow path, so each valve needs to have a large diameter to allow a large flow rate to flow. For this reason, there are problems in that the valve structure as a whole is not only expensive and large in size, but also limited in its installation location. [Problem to be solved by the invention] The problem to be solved by the invention is to provide an energy-saving lifter having a small and inexpensive valve structure. [Means for Solving the Problems] In order to solve the above problems, the present invention provides a lifter that raises and lowers a load by supplying and discharging compressed air from first and second control valves to a head chamber and a rod chamber of a drive cylinder. In the above, the first and second control valves are basically connected to first and second valve seats in first and second flow paths that communicate the second port with the first port and the third port. , first and second valve bodies that slide in the first and second back chambers to open and close these valve seats, a rod and a piston that drive these valve bodies, and a first valve that is partitioned by the piston. and a second chamber, and the first control valve connects the first port to the air source, the second port to the tank, and the third port to the head chamber of the drive cylinder. a first switching valve that communicates with the air source and switches the first chamber between the air source and the outside;
a second switching valve for switching the magnitude of the feedback air pressure of the second port in the chamber and the air pressure of the second back chamber acting in opposition thereto;
These switching valves selectively open the first and second flow paths and shut off both flow paths, and the second control valve connects the first port to the tank; The second port is connected to the rod chamber of the drive cylinder,
a first switching valve that communicates the third port with the outside and switches the first chamber between the air source and the outside; and a feedback air pressure of the second port in the second chamber and a It is equipped with a second switching valve for switching the magnitude of the air pressure in the second back chamber, and these switching valves selectively open the first and second channels and open both channels. This feature is characterized in that the system is configured to perform a shutoff. [Operation] While the second control valve maintains communication between the head chamber and the tank to the drive cylinder, the first and second switching valves of the second control valve
By supplying and discharging compressed air to the rod chamber of the drive cylinder by cutting off the flow passages, the drive cylinder can be raised and lowered. By shutting off the head chamber and rod chamber, intermediate deceleration or emergency stop can be performed. Furthermore, inching can be performed by alternately repeating the shutoff state and the previous lifting/lowering state for short periods of time. Therefore, the first and second control valves, which have a common basic configuration, can be the only large valves connected to the main flow path. [Effects of the invention] The lifter of the invention has a large valve connected to the main flow path of the head chamber and rod chamber of the drive cylinder.
By using only the first and second control valves and using mass-produced small valves in the signal system to drive these control valves, the number of large valves connected to the main flow path is reduced and the valve configuration is made smaller. This greatly eases restrictions on installation locations. In addition, by making the basic configuration of the first and second control valves the same, it is possible to reduce the variety of power-related products that are produced in high-mix, low-volume production, and to compensate for differences by replacing parts. This makes it possible to standardize the main parts and mass-produce these control valves on a standardized basis, thereby making it possible to make the valve configuration inexpensive. Furthermore, by communicating the second port of the first control valve and the first port of the second control valve with the tank, air discharged from the head chamber of the drive cylinder can be supplied to the rod chamber. can be made energy-saving. [Example] Hereinafter, an example of the present invention will be described in detail based on the drawings. In Fig. 2, 21 is an air source;
The air source 21 is connected to a tank 23 via an input port 22a and an output port 22b of the first control valve 22.
At the same time, the discharge port 22c is connected to the head chamber 24a of the drive cylinder 24, and the tank 23 is connected to the rod chamber 24b of the cylinder 24 through the input port 25a and output port 25b of the second control valve 25. The exhaust port 25c is opened to the atmosphere. The first control valve 22 includes a pressure reducing valve mechanism between the input port 22a and the output port 22b, and an on-off valve mechanism between the output port 22b and the discharge port 22c. It is possible to supply a reduced pressure from the pump to the output port 22b, and also to allow communication between the output port 22b and the discharge port 22c. Further, the second control valve 25 has an input port 25a.
A pressure reducing valve mechanism is provided between the output port 25b and the output port 25b, and an on-off valve mechanism is provided between the output port 25b and the discharge port 25c.
It is designed so that communication can be selectively switched to one of the ports, and the ports can be switched to a state where each port is cut off. Therefore, in the lifter having the above configuration, if the first and second control valves 22 and 25 are controlled respectively,
The weight load 26 can be raised and lowered, intermediately decelerated, emergency stopped, and inched. Thus, the first and second control valves 22, 25
They basically have the same structure, with the only difference being whether or not some communication holes are provided in the valve body and valve body. 3 and 4 show specific embodiments of the first and second control valves 22, 25. First control valve 2 in the embodiment shown in FIG.
2, 30 is the valve body, 31 is the input port 2
32 is an on-off valve mechanism provided between the output port 22b and the discharge port 22c, and a valve seat 33 in the pressure-reducing valve mechanism 31 and the on-off valve mechanism 32 is provided. ,34
The valve bodies 35 and 36 provided oppositely are connected to a common rod 37.
The collar 3 on the rod 37 is slidably fitted onto the rod 37.
7a, 37b and the return spring 38,
A piston 40 is provided on the rod 37, and a pilot chamber 41 and a feedback chamber 42 are defined above and below the piston 40.
2 pressure to the first and second solenoid valves 43, 4.
4 drives the piston 40 and controls the opening and closing of the valve bodies 35 and 36. On the other hand, in the second control valve 25, 50 is the valve body, 51 is the input port 25a and the output port 25b.
52 is an on-off valve mechanism provided between the output port 25b and the discharge port 25c; the pressure-reducing valve mechanism 51 and the on-off valve mechanism 52
Valve bodies 55, 5 disposed opposite to valve seats 53, 54 in
6 is slidably fitted onto a common rod 57, engaged with flanges 57a and 57b on the rod 57, and biased by return springs 58 and 59, and a piston is mounted on the rod 57. A pilot chamber 61 and a feedback chamber 62 are defined above and below the piston 60, and the piston 60 is driven by supplying and discharging pressure from both chambers 61 and 62 through third and fourth solenoid valves 63 and 64. and valve bodies 55, 56
It is configured to control the opening and closing of. In the lifter having the above configuration, the first and second control valves 22 and 25 are connected to the first to fourth solenoid valves 4.
3, 44, 63, and 64, the drive cylinder 24 can be driven as shown in Table 1.

[Table] That is, in the state (A) in which all the solenoid valves are turned off, the pilot chamber 4 of the first control valve 22
1 and the feedback chamber 42 are both open to the atmosphere, the piston 40 and the rod 37 maintain the neutral position, and the back pressure chamber 45 of the on-off valve mechanism 32 communicates with the output port 22b through the back pressure passage 46, so that the pressure reducing valve Both the mechanism 31 and the on-off valve mechanism 32 are closed, and the pilot chamber 6 of the second control valve 25 is closed.
1 and the feedback chamber 62 are both opened to the atmosphere and the piston 60 and rod 57 are maintained at the neutral position, so both the pressure reducing valve mechanism 51 and the opening/closing valve mechanism 52 are closed. Therefore, in this switching state, if the drive cylinder 24 is in a stationary state, that state is maintained, and if it is in an ascending or descending state, an emergency stop or intermediate deceleration is performed. When only the third solenoid valve 63 is turned off and the other solenoid valves are turned on, the pilot chamber 41 of the first control valve 22 is connected to the input port 22a via the pressure reducing valve 47, and the feedback chamber 42 is connected to the input port 22a via the pressure reducing valve 47. The piston 40 and rod 37 move up and down in response to the pressure difference between the pilot chamber 41 and the feedback chamber 42, respectively, at the output port 22b, operating the pressure reducing valve mechanism 31 to reduce the pressure from the input port 22a to the output port 22b. At the same time, the on-off valve mechanism 32 is opened by the pressure of the output port 22b to open the back pressure chamber 45 to the atmosphere, and the compressed air in the tank 23 is supplied to the head chamber 24a of the drive cylinder 24, and the back pressure chamber 45 is opened to the atmosphere. 2 control valve 2
Since the pilot chamber 61 of No. 5 communicates with the atmosphere and the feedback chamber 62 with the output port 25b, the piston 60 and the rod 57 move upward to open the on-off valve mechanism 52, and the pressure reducing valve mechanism 51 remains closed. Therefore, the drive cylinder 24 will rise. In the state C where only the first solenoid valve 43 is turned off and the other solenoid valves are turned on,
The pilot chamber 41 of the first control valve 22 is exposed to the atmosphere,
The feedback chamber 42 communicates with the output port 22b, the piston 40 and the rod 37 rise to open the on-off valve mechanism 32, and the pressure reducing valve mechanism 31 closes, and the pilot chamber 61 of the second control valve 25 is depressurized. Input port 25a via valve 67
In addition, the feedback chamber 62 communicates with the output port 25b, and the piston 60 and the rod 57
moves up and down in response to the pressure difference between the pilot chamber 61 and the feedback chamber 62, operating the pressure reducing valve mechanism 51 to supply reduced pressure from the input port 25a to the output port 25b, while the on-off valve mechanism 52 is closed. is maintained, and therefore the drive cylinder 24 will be lowered. Note that the pressure reducing valve 4 in the first control valve 22
7 is for adjusting the pressure inside the tank 23, and is a pressure reducing valve 67 in the second control valve 25.
is for adjusting the pressure at the output port 25b. In addition, the first and third solenoid valves 43, 63
Instead, a 3-position solenoid valve that also has these functions can be used, and furthermore, in place of the second solenoid valve 44, two 2-position 3-port solenoid valves that share the functions can also be used. In the figure, 48, 68 are pilot flow paths, 49, 6
9 indicates a feedback flow path. FIG. 4 shows a lifter using first and second control valves 22, 25 having a structure slightly different from that of the above embodiment, but this embodiment is different from the embodiment of FIG. 3 above. , the feedback passages 49 and 69 in the first and second control valves 22 and 25 are opened directly into the feedback chambers 42 and 62, and the valve body 56 in the opening/closing valve mechanism 52 of the second control valve 25.
In addition to eliminating the collar on the rod 57 that engages with the valve body 56, a back pressure chamber 65 is formed behind the valve body 56, and compressed air can be supplied and discharged through the back pressure passage 66. The only difference is in three points, etc. Therefore, the same or corresponding parts as in the embodiment shown in FIG. 3 are denoted by the same reference numerals, and a description of the structure thereof will be omitted. In the embodiment shown in FIG. 4, the first and second control valves 22 and 25 are controlled by the first to third solenoid valves 71 to 73, so that the operation as shown in Table 2 is achieved. The drive cylinder 24 can be driven to

[Table] That is, in the state (A) in which all the solenoid valves are turned off, the pilot chamber 4 of the first control valve 22
1 is in communication with the input port 22a via the pressure reducing valve 47 and the solenoid valve 73, and the feedback chamber 42 is always in communication with the output port 22b. It moves up and down in response to the pressure difference, operates the pressure reducing valve mechanism 31, and reduces the pressure and supplies it from the input port 22a to the output port 22b. Since the on-off valve mechanism 31 is closed to communicate with the air, and the pilot chamber 61 of the second control valve 25 communicates with the atmosphere, and the feedback chamber 62 is constantly communicated with the output port 25b, the piston 6
0 and the rod 57 move upward, the pressure reducing valve mechanism 51 is closed by the return spring 58, and the back pressure chamber 65 communicates with the input port 22a via the back pressure passage 66, the solenoid valve 72, and the pilot passage 48. The opening/closing valve mechanism is also closed, and therefore the drive cylinder 24 which is in a stationary state maintains that state, and when it is in an ascending or descending state, an emergency stop or an intermediate deceleration is performed. In state B where the first and second solenoid valves 71 and 72 are turned on and the third solenoid valve 73 is turned off, the pilot chamber 4 of the first control valve 22
1 communicates with the input port 22a, and the feedback chamber 42 communicates with the output port 22b, so similarly to state A, the pressure reducing valve mechanism 31 operates to supply reduced pressure from the input port 22a to the output port 22b, while the back Since the pressure chamber 92 is open to the atmosphere, the on-off valve mechanism 32 is opened by the pressure of the output port 22b, and compressed air from the tank 23 is supplied to the head chamber 24a of the drive cylinder 24. Further, the pilot chamber 61 of the second control valve 25 communicates with the atmosphere, and the feedback chamber 62 communicates with the output port 2.
5b, the piston 60 and rod 57 move upward, and the back pressure chamber 65
In order to open to the atmosphere, the on-off valve mechanism 52 opens to the pressure of the output port 25b, and therefore the drive cylinder 24 rises. When the first and third solenoid valves 71 and 73 are turned on and the second solenoid valve 72 is turned off, the pilot chamber 4 of the first control valve 22
1 and the back pressure chamber 45 communicate with the atmosphere, and the feedback chamber 42 communicates with the output port 22b.
is closed, and the pilot chamber 61 and back pressure chamber 65 of the second control valve 25 are connected to the input port 22a, and the feedback chamber 62 is connected to the output port 25b, so that the piston 60 and the rod 57 are connected to the pilot chamber 61. and feedback room 62
moves up and down in response to the pressure difference between the input port 25a and the output port 25.
At the same time, the on-off valve mechanism 51 is closed and the drive cylinder 24 is lowered. In the lifter shown in FIG. 4, the return springs 39 and 59 in the first and second control valves 22 and 25 can be omitted, and the back pressure chambers 45 and 59 of the control valves 22 and 25 can be omitted. 65 together 1st
It is also possible to connect to the input port 22a through the solenoid valve 71 of the solenoid valve 71, thereby simplifying the structure and control by using only two solenoid valves for the signal system. The first and second control valves shown in FIGS. 3 and 4 described above have basically the same structure, and in particular, the valve body is made common, and the feedback flow path, back pressure flow path, etc. The only difference is whether a hole is to be drilled or not, and the parts installed in the valve body, such as rods and valve discs, are also slightly different, and by simply replacing them, the control valve can be adjusted. This makes it possible to provide various functions. Such a configuration is extremely effective in reducing the types of power-related products that are produced in high-mix, low-volume production, and in making it possible to mass-produce standardized products.

[Brief explanation of drawings]

Fig. 1 is a block diagram of a conventional example, Fig. 2 is a block diagram of an embodiment of the present invention, and Figs. 3 and 4 are different sections of the present invention showing the first and second control valves in cross section. FIG. 21... Air source, 22... First control valve, 22
a...Input port, 22b...Output port, 22
c...Discharge port, 23...Tank, 24...Driving cylinder, 24a...Head chamber, 24b...Rod chamber, 25...Second control valve, 25a...Input port, 25b...Output port, 25c...Discharge port, 31, 51...Pressure reducing valve mechanism, 32, 52
...Opening/closing valve mechanism, 43, 44, 63, 64, 71
~73... Solenoid valve.

Claims (1)

[Claims for Utility Model Registration] A lifter that raises and lowers a load by supplying and discharging compressed air from first and second control valves to a head chamber and a rod chamber of a drive cylinder, wherein the first and second control valves are , basically the second
first and second valve seats in first and second flow paths that communicate the port with the first port and the third port;
First and second valve bodies that slide in the first and second back chambers to open and close these valve seats, rods and pistons that drive these valve bodies, and first and second valve bodies that are partitioned by the pistons. and a second chamber, and the first control valve communicates with the first port to the air source, the second port to the tank, and the third port to the head chamber of the drive cylinder. a first switching valve that switches the first chamber between an air source and the outside; a feedback air pressure at a second port in the second chamber; and an air pressure in a second back chamber that acts in opposition to the feedback air pressure at the second port. and a second switching valve for switching the size of the first and second channels, and these switching valves selectively communicate the first and second channels and disconnect both channels, The second control valve communicates the first port with the tank, the second port with the rod chamber of the drive cylinder, and the third port with the outside, and connects the first chamber with the air source and the outside. and a second switching valve for switching the magnitude of the feedback air pressure of the second port in the second chamber and the air pressure of the second back chamber acting in opposition thereto. A lifter characterized in that the switching valves selectively communicate the first and second flow paths and disconnect both flow paths.