JPH0632958Y2 - Balancer for cargo handling and air cylinder device for the balancer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a cargo handling balancer using an air cylinder device as a load balance drive source, and an air cylinder device of the balancer.

[Prior Art] When moving a load in a three-dimensional space, it is known to use a so-called manual loader type cargo handling balancer in which vertical movement is performed by power, and turning and horizontal movement are manually performed. . In this balancer for cargo handling, a parallel link mechanism is adopted as an arm device for holding and moving loads, and a structure using an air cylinder device for load balancing driving of the arm device is Japanese Patent Publication No. 58-12196.
It is disclosed by the publication. In such a known cargo handling balancer, the air cylinder device is fixed to the base with the piston rod facing upward and the cylinder housing is fixed to the base, and the arm device attaches the bracket to the tip of the piston rod and supports the arm on the bracket. One fulcrum for this purpose, and the other fulcrum is fixed to the base. Further, the arm device extends the arm backward so that its own weight does not cause an excessive load on the forward and backward movements of the arm. The balance weight is provided in the extension portion.

However, in the cylinder device, when the load applied to the arm device suddenly becomes small, the piston suddenly returns and the arm bounces up, which could lead to an accident. Therefore, JP-B-61-6074 and JP-B-60- Japanese Patent No. 6641 discloses an air cylinder device that prevents jumping of an arm. In this air cylinder device, the piston rod is provided upward like the cylinder device, but the piston rod is hollow and has a pipe shape, and the inside of the rod is filled with oil and is axially moved. A moving partition member divides the chamber into two chambers. Further, the partition member opens a through hole for communicating the two chambers with each other, and when the piston rod is raised, the through hole is opened. A valve that closes the hole is provided with a compression coil spring interposed, and when the arm device suddenly becomes unloaded from the loaded state, the oil inside the guide rod that directs the valve passes through the through hole of the partition member. Flow from the lower chamber to the upper chamber, and the dynamic pressure of the oil at that time presses the valve against the elastic force of the compression coil spring, and the valve is pressed. Close the through holes, to prevent rapid descent of the piston rod, it was to serve to prevent the jumping of the arm coupled to the rod.

[Problems to be Solved by the Invention] However, in the above-described conventional cargo handling balancer, since the structure in which the arm device is connected to the upward piston rod of the air cylinder device must be adopted, the piston rod having a relatively small diameter is used. The arm device could not be directly connected to, and a special bracket had to be attached to avoid the problem. Therefore, it is necessary to raise the mounting position of the arm device by the size of the bracket. Therefore, if the arm device is to be lowered, the air cylinder device must be lowered accordingly. Therefore, in a usage mode in which the cargo handling balancer is installed on the wall surface or suspended on the ceiling, the air cylinder protruding downward is used. The problem that the device interferes with the work and may hit the worker is unavoidable.

In addition, in the conventional air cylinder device with the piston rod facing upward, there is a drawback that the impact absorption power is reduced with respect to the cross-sectional area of the piston by the cross-sectional integral of the piston rod, and the elastic force of one compression coil spring is increased. With the structure in which the valve operates against this and the through hole of the partition member is closed, the work of stopping the movement of the piston rod was too rapid, and there was concern that the reaction at that time would adversely affect the entire balancer mechanism. .

An object of the present invention is to provide a cargo handling balancer that solves the above-mentioned conventional problems. At the same time, the air cylinder device serving as a load balance drive source is downsized, and the cylinder device is not loaded. Even when suddenly no load is applied, it is intended to exert a sudden jumping-up prevention effect of the arm device without giving a reaction to all the mechanisms.

[Means for Solving the Problems] As a means for solving the above problems, the cargo handling balancer of the present invention has a plurality of arms and links each having a basic structure of a quadrilateral deformable by link coupling. The arm device composed of the connected body is attached to the base so that it can be easily manually operated in the front-back direction by the action of the tension spring, and can be manually operated in the up-down direction, the left-right direction, and the load of the arm device. In a cargo handling balancer in which an air cylinder device as a balance drive source is connected to a fulcrum of the arm device on the base, the cylinder rod is turned upside down to make the piston rod downward, and the piston rod A hollow body to fix the lower part of the piston rod on the base,
An oil replenishment tank for filling the hollow piston rod is provided in an upper portion of the air cylinder device so as to be isolated from the inside of the cylinder housing, and a guide rod is fixed toward the inside of the hollow piston rod. In the inside of the piston rod filled with, a partition member that descends when the piston that moves up and down inside the cylinder housing is located above the housing in a relative positional relationship with the cylinder housing is urged downward. A compression coil spring is interposed so as to be slidably provided on the guide rod, and the partition member divides the inside of the piston rod into an upper chamber and a lower chamber. From the bottom when the cylinder housing suddenly descends through the through hole provided in the partition member for communicating with the chamber A chained disc-shaped valve is provided so as to be freely contactable and separable with respect to a partition member with a compression coil spring urging downward, and the lower part of the valve is provided with the partition when the cylinder housing is in a stationary position. It employs a structure that is supported by a stopper to form a slight gap with the member.

Further, the air cylinder device has a piston rod formed of a hollow body having a fixing portion on the base at the bottom,
An oil replenishment tank for filling the hollow piston rod is provided in an upper portion of the cylinder housing in a state of being isolated from the inside of the cylinder housing, and a guide rod is fixed toward the inside of the hollow piston rod.
Inside the piston rod filled with oil, a partition member that moves downward when the piston that moves up and down inside the cylinder housing moves above the housing in a relative positional relationship with the cylinder housing is attached downward. A compression coil spring that urges is interposed so as to be slidably provided on the guide rod, and the partition member divides the inside of the piston rod into an upper chamber and a lower chamber. A compression coil for urging downward a disk-shaped valve that closes a through hole provided in the partition member for communicating between the lower chamber and the lower chamber when the cylinder housing suddenly descends toward the piston mounting portion. It is provided so as to be able to come in contact with and separate from the partition member with a spring interposed, and the cylinder housing is at a stationary position below the valve. Can the then supported by a stopper to form a slight gap between the partition member, the cylinder housing is adopted a structure which is characterized in that vertically moves with respect to the piston rod.

[Operation] The cargo handling balancer of the present invention can be used by attaching a load to the tip of the arm device and supplying compressed air of a predetermined pressure to the air cylinder device. When the luggage is lifted, if compressed air is supplied to the cylinder housing from below, the cylinder housing descends with respect to the piston that is fixed to the piston rod and maintains a fixed position. At this time, the arm device rises, The load can be lifted in an unloaded state by the action of air pressure preset according to the weight of the load.

When the load is removed from the arm device and the load acting on the arm device suddenly disappears, the load balance due to the air pressure supplied to the air cylinder device is lost, so that the cylinder housing tries to descend rapidly. At this time, the guide rod integrated with the cylinder housing also tries to go down inside the piston rod together with the partition member.
The lower chamber, which is partitioned by the partition member inside the piston rod, contracts its volume, and the oil in the chamber tries to suddenly flow toward the upper chamber through the through hole of the partition member,
The pressure of the oil generated at this time is received by the lower surface of the disc-shaped valve, and the valve is pushed upward, which immediately closes the through hole of the partition member from below, and inside the piston rod, the upper chamber and the lower chamber are closed. The cylinder housing and the cylinder housing are prevented from communicating with each other, and the movement of the cylinder housing that attempts to descend is immediately stopped. As a result, the arm device is prevented from jumping up.

In this way, even after the disc-shaped valve closes the through hole of the partition member, the guide rod can be relatively lowered against the elastic force of the spring, so that the spring can prevent the spring from jumping. It functions as a bumper that absorbs reaction force, and prevents the arm device from jumping up without impact.

[Embodiment] FIG. 1 is a side view of this embodiment, and the cargo handling balancer 1 is horizontally rotatably supported on a column 3 standing on a base (not shown). Reference numeral 5 denotes a base provided on the column 3 so as to be horizontally rotatable via a bearing or the like (not shown). The base 5 includes an arm device 7 configured by a complex parallel link mechanism and the arm device 7. An air cylinder device 9 for balance driving is installed.

The air cylinder device 9 is installed vertically and has a piston rod 13 protruding downward from the cylinder housing 11.
The lower portion of the cylinder housing 11 is fixed on the base 5, and the cylinder housing 11 itself is provided so as to move up and down.

The air cylinder device 9 is provided with an operation portion 1 provided near a hook 15 for hanging a load provided at a tip portion of the arm device 7.
The balance is driven by operating 7.
When the air cylinder device 9 is activated, when the cylinder housing 11 is moved up and down, it is driven so that the relative load to the load supported by the arm device becomes zero.

Next, the arm device 7 will be described in detail.

The arm device 7 is composed of a composite parallel link mechanism including a first parallel link mechanism 21, a second parallel link mechanism 23, and a third parallel link mechanism 25.

The first parallel link mechanism 21 has a main arm 29 rotatably supported by support shafts 27 provided on both sides of the cylinder housing 11, and a free end portion of the main arm 29 has an upper end portion of a suspension arm 31. The main shaft 29 is rotatably connected to the main arm 29, the link 35 is rotatably connected to a support shaft 37 provided near the both support shafts 27 of the main arm 29, and the rear part is connected to the link 35 by a support shaft 41. The main part of the main arm 29, the suspension arm 31, the link 35
Together with this, it is configured by rotatably connecting to the suspension arm 31 so as to form a quadrangle.

In the second parallel link mechanism 23, a bell crank 43 is provided on the upper support shaft 33 of the suspension arm 31, and a rod link 51 is rotatably connected to a support shaft 45 on the front side of the bell crank 43. The lower ends of both 51 and 31 are attached to the front and rear of the bracket 47 for attaching the hook 15 so that the link 51 and the suspension arm 31 are parallel to each other.
3 and a spindle 49 are connected.

The third parallel link mechanism 25 is disposed above the first parallel link mechanism 21, and the upper side of the bell crank 43 and the cylinder housing 11 are rod links via support shafts 57 and 59, respectively. The rod link 55 and the main arm 29 are rotatably connected to each other at 55 and are arranged in parallel.

A frame 61 is fixed to the base 5 in parallel in the front-rear direction so as to surround both sides and a back surface of the air cylinder device 9.
A vertical guide 67 for vertically guiding the guide rollers 63, 65 provided on 7, 59 is provided, and a horizontal guide 71 and a horizontal guide 73 for vertically guiding the guide roller 69 provided on the support shaft 41 are vertically provided. They are provided so as to face each other. The upper horizontal guide 73 is a guide roller 6
9 is regulated from moving away from the lower horizontal guide 71 and moving upward, but this guide 73 prevents the arm device 7 from rising excessively while working together with the cylinder device 9, and It also functions to prevent jumping up when the load suddenly becomes unloaded, such as when detached.

In the arm device 7, when the air cylinder device 9 is driven to move the cylinder housing 11 up and down, the guide rollers 63 and 65 integrated with the cylinder housing 11 move up and down, and the support shaft 37 or 41 serves as a fulcrum. The suspension arm 31 moves up and down. Therefore, when the cylinder housing 11 rises, the guide rollers 63, 65 rise along the vertical guide 67 accordingly, and the guide roller 69 moves rightward in FIG. The arm 29 gradually takes a forward downward posture and descends,
Along with that, the suspension arm 31 is lowered. On the other hand, when the cylinder housing 11 descends, the guide rollers 63 and 65 descend along the inside of the vertical guide 67 having a U-shaped cross section, and the guide roller 69 moves leftward in FIG. When the main arm 29 gradually moves upward, the main arm 29 takes an upward posture, and accordingly, the hanging arm 3
1 goes up.

In this arm device 7, the support shafts 27, 41, 53 are on a straight line, and the triangles 27, 37, 41 and the triangles 27, 33, 53 are always similar figures regardless of the orientation of the arm device 7. Therefore, the ratio of the arms and links around the support shaft 27 is constantly constant, and the thrust of the air cylinder device 9 is determined by the ratio of the arms and links and the magnitude of the load, and is always constant. The force generated by the air cylinder device 9 reduces the weight of the parcel relative load 0
With a force that balances the load, the load can be suspended and moved in a substantially unloaded state regardless of the direction of the arm device 7.

In FIG. 1, reference numeral 75 is a tension coil spring stretched between the cylinder housing 11 and the main arm 29, and the action of this spring supports the weight of the arm device 7 in the longitudinal direction of the suspension arm 31. The flow of is suppressed.

FIG. 2 shows the details of the air cylinder device 9, which is a cylinder cylinder 79 included in the cylinder housing 11.
81 that reciprocates in the vertical direction inside the cylinder, a cylindrical hollow piston rod 13 that is fixed to the lower part of the piston 81 and projects from the lower part of the cylinder housing 11, and the oil that is housed inside this piston rod 13. The piston rod 13 is fixed on the base 5 in an upright state. This air cylinder device 9 is a cylinder cylinder 7 partitioned by a piston 81.
Compressed air is supplied to the inside of the port 9 from a port 89 provided in the lower part, so that the piston 81 can be moved up and down or stopped at an intermediate position by the pressure difference between the upper and lower chambers partitioned by the piston 81. Has become.

The flow rate control unit 85 includes a guide rod 91 that penetrates the inside of the hollow piston rod 13 and the piston 81 and is fixed to the cylinder housing 11.
1, a partition member 93 having a compressed air through hole 93T is provided so as to be slidably contactable with the inner peripheral surface of the piston rod 13.
The interior of the piston rod 13 is separated into an upper chamber 95U and a lower chamber 95D. Reference numeral 97 denotes a disc-shaped valve that closes the through hole 93T of the partition member 93 from the lower end side of the piston shaft 13 in the process in which the piston rod 13 is drawn into the cylinder cylinder 79 and the lower chamber 95D contracts. Numeral 93 is elastically bulged downward by a compression coil spring 99 so as to open when the arm device 7 is in a stationary state. Reference numeral 103 denotes a compression coil spring having a larger elastic force than that of the compression coil spring 99. The compression coil spring 103 presses the partition member 93 downward and elastically repels the stopper 101 screwed to the lower end of the guide rod 91. There is.

At the upper end of the cylinder housing 11, the piston rod 1
Tank 105 for replenishing the oil filling the inside of 3
The inside of the piston rod 13 is always filled with oil by the oil tank 105, and the inside of the tank and the inside of the piston rod 13 communicate with each other through a passage 107 formed in the guide rod 91. ing.

Next, the operation of this balancer will be described.

The air that has been set to a predetermined pressure in advance is supplied to the air cylinder device 9 by the operation of the operation unit 17, and the port 8
When the cylinder housing 11 is lowered by the pressure of the air supplied from 9 and the arm device 7 is biased upward, the action of the tension coil spring 75 can be assisted to keep the arm device 7 in the raised position. In this case, the pressure applied to the piston 81 in the vertical direction maintains an equilibrium state, and the arm device 7 is maintained in a substantially floating state. Therefore, the operator swings within the movable range of the arm device 7, moves forward and backward, It can be moved horizontally to the left and right. Since the pressure of the air supplied from the port 89 into the cylinder cylinder 79 is always kept at a predetermined pressure, the hanging arm 31 can be lowered together with the arm device 7 when the load is moved to a predetermined position. If so, the luggage can be smoothly lowered to a predetermined position.

In such a series of loading and unloading work, if the suspended load is dropped while the cylinder device 9 balances the load, the cylinder device 9 will be in a load state immediately, and the cylinder housing 11 will suddenly drop. Trying to go down,
At this time, since the guide rod 91 integrated with the cylinder housing 11 also tries to lower inside the piston rod 13 together with the partition member 93, the volume of the lower chamber 95D contracts so that the oil inside the chamber 95D passes through the through hole 93T. Upper chamber 9
It begins to flow rapidly toward 5U. This rapid flow of oil pushes the valve 97 upward to close the through hole 93T of the partition member 93. As a result, the partition member 93 is prevented from abruptly descending, the cylinder housing 11 does not abruptly descend, and the instantaneous jumping up of the arm device 7 is prevented. At this time, since the partition member 93 moves on the guide rod 91 against the elastic force of the compression coil spring 103, the guide rod 91 keeps the compression coil spring even after the valve 97 closes the through hole 93T of the partition member 93. 10
The compression coil spring 103 functions as a bumper that absorbs a reaction force at the time of preventing jumping, by relatively lowering against the elastic force of 3.

The present invention has been described above in detail based on the embodiments, but the present invention is not limited thereto and can be variously modified without departing from the gist thereof.

[Effects of the Invention] In the cargo handling balancer of the present invention, the piston rod filled with oil is fixed on the base, while the cylinder housing accommodating the piston integrated with the piston rod moves up and down, and Since the cylinder housing also serves as a bracket for supporting the fulcrum of the arm device with respect to the piston rod, a bracket for supporting the fulcrum of the arm device is specially attached to the piston rod that moves up and down like a conventional balancer. The height of the balance drive part of the arm device can be kept low enough not to interfere with the work, compared to the structure that is installed and the structure that has the cylinder device with the piston rod facing upward. , It is not necessary to increase the diameter of the piston rod because the bracket is specially provided. Therefore, there is a feature that the diameter of the cylinder device can be reduced by itself. Therefore, even when the cargo handling balancer of the present invention is installed on a wall or ceiling crane, the cylinder housing does not project below the arm device as in the conventional case. This has the effect of avoiding a collision accident in which a person hits his head.

Moreover, the cylinder device used for the cargo handling balancer has a suppressing function of preventing the cylinder housing from dropping rapidly toward the mounting portion of the piston rod, and the valve mechanism therefor has two compression coil springs, one large and one small. Since the movement of the partition member is controlled via the, even if the load acting on the cylinder housing suddenly disappears, the inside of the piston rod functions as an oil bumper and reliably prevents the arm device from jumping up without recoil. There is an effect that can be done.

[Brief description of drawings]

The drawings show one embodiment of the present invention. FIG. 1 is a side view in which a part of a cargo handling balancer is cut away, and FIG. 2 is a longitudinal sectional view of a cylinder device. 1 ... Balancer for cargo handling, 5 ... Base, 7 ... Arm device, 9 ... Cylinder device, 11 ... Cylinder housing, 13 ... Hollow piston rod, 81 ... Piston,
91 ... Guide rod, 93 ... Partition member, 93T ...
Oil passage, 95U ... upper chamber, 95D ... lower chamber, 97
...... Disk valve, 99, 103 ...... Compression coil spring, 101 ・ ・ ・ Stopper, 105 ・ ・ ・ Oil supply tank.

Claims (2)

[Scope of utility model registration request] 1. An arm device, which has a basic structure of a quadrilateral deformable by link connection and is composed of a plurality of arms and a link body, is easily manually operated in the front-back direction by the action of a tension spring. It is possible to mount the air cylinder device as a load balance driving source of the arm device on the base so that it can be manually operated in the vertical and horizontal directions, and the air cylinder device is connected to the fulcrum of the arm device on the base. In the cargo handling balancer provided as described above, the cylinder device is turned upside down so that the piston rod faces downward, and the piston rod is formed of a hollow body, and the lower portion of the piston rod is fixed on the base.
An oil replenishment tank for filling the hollow piston rod is provided in an upper portion of the air cylinder device so as to be isolated from the inside of the cylinder housing, and a guide rod is fixed toward the inside of the hollow piston rod. In the inside of the piston rod filled with, a partition member that descends when the piston that moves up and down inside the cylinder housing is located above the housing in a relative positional relationship with the cylinder housing is urged downward. A compression coil spring is interposed so as to be slidably provided on the guide rod, and the partition member divides the inside of the piston rod into an upper chamber and a lower chamber. From the bottom when the cylinder housing suddenly descends through the through hole provided in the partition member for communicating with the chamber A chained disc-shaped valve is provided so as to be freely contactable and separable with respect to a partition member with a compression coil spring urging downward, and the lower part of the valve is provided with the partition when the cylinder housing is in a stationary position. A cargo handling balancer supported by a stopper for forming a slight gap between the member and the member. 2. An air cylinder for a cargo handling balancer, which is used as a load balance driving source of an arm device having a basic structure of a quadrilateral configured to be deformable by linking and which is composed of a plurality of linked arms and links. In the device, the piston rod is constituted by a hollow body, the lower portion of the piston rod has a fixing portion on the base, and the upper portion of the cylinder device is provided with a portion of the oil filled in the hollow piston rod. A refueling tank is provided so as to be isolated from the inside of the cylinder housing, a guide rod is fixed toward the inside of the hollow piston rod, and a piston that moves up and down inside the cylinder housing is provided inside the piston rod filled with oil. In the relative positional relationship with the recliner housing, it descends when it is located above the housing. A partition member is slidably provided on the guide rod with a compression coil spring urging downward, and the partition member divides the interior of the piston rod into an upper chamber and a lower chamber. On the rod,
A disk-shaped valve that closes a through hole provided in the partition member for communicating the upper chamber and the lower chamber from below when the cylinder housing is suddenly lowered toward the mounting portion of the piston is urged downward. A compression coil spring is interposed between the partition member and the partition member so that the compression coil spring can be brought into contact with and separated from the partition member. Further, when the cylinder housing is at a stationary position, a small gap is formed between the valve and the partition member. The air cylinder device is characterized in that the cylinder housing moves up and down with respect to the piston rod.