JPH0825711B2 - Vibration control for rotary damper and crane monitor camera - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a rotary damper capable of absorbing the impact of a rotary motion, and a vibration control device for a crane monitor camera using the rotary damper.

[Problems to be Solved by Prior Art and Invention]

Currently, large cranes are often used in the construction of large buildings, but in this type of crane, the hooks located in places that cannot be seen from the operator's cab may be used for unloading and unloading. A monitor device that attaches a monitor camera near the boom tip and monitors the behavior of the hook is widely adopted.

In this device, the monitor camera is hung from the boom with a wire, but if the monitor camera is fixed to the boom, the direction of the monitor camera will change due to the change of the boom angle, and the hook to be monitored will be changed. This is to prevent the monitor camera from being out of the viewing angle. In addition, simply hanging the monitor camera causes the monitor camera to shake freely due to boom movement, wind, etc. Therefore, in order to prevent this, a weight is attached to the monitor camera to eliminate this point.

However, there was a problem that a considerable amount of weight (for example, reaching 150 kg) was required to suppress the movement of the monitor camera.

In order to solve this problem without using a weight, it is conceivable to employ a damper (buffer) that is generally used for so-called shock absorption.

The dampers currently known are used, for example, as shown in FIG. 6 for the support mechanism of the wheels of automobiles, aircrafts, etc., and for the shock absorption of the carrier as shown in FIG. There are things that are.

In the example shown in FIG. 6, the oil 2 enclosed in the cylinder 1 is moved in and out through the small holes 4 as the wheel 3 moves up and down to absorb the shock. Generally, a vehicle or the like is designed to absorb a shock in both directions. In the example of FIG. 7, the oil 6 and the spring 7 are put in the cylinder 5, and the piston 8 is driven by the resistance force of the oil 6 which escapes from the small hole 9 by the operation of the piston 8 in the direction of the arrow and the elastic force of the spring 7. It absorbs the impact force applied to the. A shock absorber such as a conveyor of this kind absorbs a one-way shock.

By the way, there are not only a linear direction but also a rotational direction as a direction to which an impact is applied, but the conventional damper described above is troublesome to absorb the impact with respect to the swinging motion.

For example, in order to absorb the shock in the rotational direction using the damper shown in FIG. 7, a device shown in FIG. 8 can be considered. In this example, the dampers shown in FIG. 7 are opposed to each other, the ends of the pistons 9 and 9 are connected by a connector 10, and the rotary shaft 11 is attached to the connector 10. Is converted into a linear motion and buffered.

That is, the conventionally known damper necessarily requires a mechanism for changing the rotary motion into the linear motion, which causes a problem that the device configuration becomes large. This point is the same when a damper as shown in FIG. 6 is used. Further, in the case of the configuration as shown in FIG. 8, it is difficult to make the performances of the pair of dampers the same, so that there is a problem that the cushioning performance must be poor in symmetry.

The present invention has been made in view of the above-mentioned conventional problems, and a rotary damper capable of absorbing a shock accompanied by a rotational movement having good left-right symmetry with a compact shape without the need for a movement direction conversion mechanism and the rotary damper. It is an object to provide a vibration control device for a used crane monitor camera.

[Means for solving the problem]

The rotary damper according to the present invention comprises a housing having a cylindrical hollow portion with both ends blocked therein, and a shaft that penetrates the hollow portion along the axis of the hollow portion,
The housing is provided with a projecting wall portion projecting over the entire length of the hollow portion in the axial direction and the projecting end of the hollow portion abutting on the side surface of the shaft. The inside of the above hollow part is divided into two chambers,
In addition, a damper main body having an inflow / outflow hole opening to the outside of the housing in each of these two chambers, and a flow passage inside the housing, and a variable throttle valve that serves as a resistance against the flow of the viscous fluid are provided in the flow passage. And a pressure accumulating chamber for absorbing the volume change of the viscous fluid is provided in communication with the flow passage, and two inflow / outflow ports of the flow passage are opened outside the housing. The housing of the expansion device part is mounted on the outer peripheral surface of the housing of the damper body, and the two inflow / outflow ports of the flow path of the expansion device part are directly connected to the inflow / outflow holes of the damper main body part. A viscous fluid is sealed in the hollow portion and in the flow path of the throttle device, and the rotational energy of the housing or shaft of the damper body is absorbed by the resistance force of the throttle valve. Than it is.

According to another aspect of the present invention, there is provided a vibration control device for a crane monitor camera according to the present invention, wherein a mounting base is hung up and down near a boom tip of a crane, and the mounting base is mounted on the mounting base.
The rotary damper housing or shaft is connected.

The rotary damper according to the present invention is not limited to the size, shape, application, etc. shown above and below, and the type of crane is not limited to the same.

〔Example〕

Next, embodiments of the present invention will be described with reference to the drawings.

1 to 4 show an embodiment of the present invention. In this example, as shown in FIGS. 3 and 4, a monitor camera device 31 is hung on the tip of a boom 30 of a tower type jib crane. The behavior of the hook 32 and the state in the vicinity thereof can be monitored.

The monitor camera device 31 is positioned such that the monitor camera main body 34 with the rotary damper 33 mounted on the upper side and the monitor camera main body 34 is sandwiched from above, and is suspended at both ends of the rotary shaft 35 of the rotary damper 33. It consists of a base 36. The winch wires 37, 37 are hooked to the hanging base 36, and the monitor camera body 34
A power supply line 38 connected to is penetrating the upper surface. A mounting base 39 for suspending the monitor camera device 31 is fixed to the boom 30 by bolting. A winch wire 37 and a rope wheel 40 for hanging the power line 38 are mounted on the mounting base 39.
38 is connected to the monitor camera device 31 through the hole 41 as described above.

The winch wire 37 is for raising and lowering the monitor camera device 31, and normally, as shown in FIG. 3, the winch wire 37 is fully wound and the monitor camera device 31 is pulled up to the vicinity of the tip of the boom 30. It can be lowered to the ground for maintenance. The power supply line 38 is for supplying power to the monitor camera main body 34, but it can be wound together with the winch wire 37.

As shown in FIGS. 1 and 2, the rotary damper 33 has a structure mainly composed of a damper main body and a diaphragm device, and a housing of the damper main body (hereinafter simply referred to as “rotor shaft 35”) protruding from both ends. A damper housing (hereinafter simply referred to as a throttle housing) 44 having a variable throttle valve 43 built in is mounted on a damper housing (42)
Both ends of 35 are fixed to the upper part of the monitor camera body 34 through the mounting angles 45, 45, and fixed to the hanging base 36 as described above.

The damper housing 42 has an outer shape of a straight tube, and has a hollow portion 46 having a cylindrical shape formed therein. The hollow portion 46 is closed by covering both ends with a cover 47. The cover 47 has a penetrating portion of the rotary shaft 35 protruding as shown in FIG. 2, and this portion is fitted into the hole 48 of the mounting angle 45 so that the damper housing 42 is integrated with the monitor camera body 34.

A projecting wall 49 is screwed into the hollow portion 46. The projecting wall 49 is provided so as to project over the entire length in the axial direction of the hollow portion 46, and the tip end thereof is formed in a height dimension and shape that abuts against the side surface of the rotary shaft 35 as shown in the drawing.

On the other hand, a vane plate 50 is screwed to the rotary shaft 35.
The vane plate 50 has its tip abutting against the wall surface of the hollow portion 46, and its contact length is the same as that of the protruding wall 49.
It extends over the entire length of 46 in the axial direction. As a result, the hollow portion 46 is divided into two chambers A and B by the protruding wall 49 and the vane plate 50. Damper housings in rooms A and B respectively
42 Inflow / outflow holes 52, 53 opening to the outside are provided, and both inflow / outflow holes 52, 53 communicate with a flow path 60 in the throttle housing 44, and the rooms A and B are short-circuited via the flow path 60. It is in a state. A viscous fluid (hereinafter simply referred to as oil) 51 that fills the chambers A and B and the flow path 60 is enclosed.

In the flow passage 60 in the throttle housing 44, the enclosed oil 51
There is provided a variable throttle valve 43 which becomes a resistance against the flow.
Further, the throttle housing 44 is provided with a pressure accumulating chamber 54 in communication with the variable throttle valve 43 in order to absorb the volume change of the oil 51 due to the outside air temperature and the like. That is, when the crane equipped with this device is installed in a place where sunlight is severe, the room A,
The oil 51 contained in B easily changes in volume due to the outside air temperature, and the expansion energy thereof causes excessive pressure in the hollow portion 46 of the housing 42, which may cause damage. In consideration of this, the pressure accumulating chamber 54 is provided with a spring 55 and a piston 56 for absorbing the volume change of the oil 51.

The diaphragm housing 44 is mounted on the outer peripheral surface of the damper housing 42 and is fixed by an appropriate means (not shown). The flow passage 60 has openings 52A, 53A to the outside at positions corresponding to the inflow / outflow holes 52, 53 of the damper housing 42.
As described above, the inflow / outflow holes 52 and 53 are provided in the state where the throttle housing 44 and the damper housing 42 are combined as described above.
The openings 52A and 53A are directly connected to each other and connected without requiring external piping to form a so-called closed system. Of course, these inflow / outflow holes 52 and 53 and the openings 52A and 53A of the flow path 60
Although not shown, an appropriate connector or the like may be used for the direct connection.

 Next, the operation of this embodiment will be described.

When the relative angle between the housing 42 and the rotary shaft 35 changes due to an external force, the oil 51 enclosed in the chambers A and B, which divide the hollow portion 46, passes through the inflow / outflow holes 52 and 53 toward the other chamber side. Flowing. For example, if the monitor camera main body 34 is shaken and the housing 42 is rotated to the right (in FIG. 1) and the room A becomes narrower due to the position movement of the vane plate 50, the oil 51 in the room A flows from the inflow / outflow hole 52. It flows into the room B from the inflow / outflow hole 53 through the variable throttle valve 43.

At this time, the variable throttle valve 43 generated against the flow of the oil 51
The throttling effect due to becomes resistance against the swing of the rotating shaft 35,
The rotational energy generated by the rotational movement of the rotary shaft 35 is absorbed by this resistance, and the swing motion generated in the monitor camera body 34 is buffered as it is without being converted into a linear motion.

Of course, even if the rotation direction is opposite to the above-mentioned state, and the monitor camera body 34 itself is not shaken, the boom 30
The same applies when the suspension base 36 moves due to the movement of the side and the monitor camera body 34 side is relatively shaken.

In order to use the rotary damper according to the present embodiment, there are a method of fixing the housing 42 and attaching the rotating shaft 35 to the supporting object, and a method of fixing the rotating shaft 35 and attaching the housing 42 to the supporting object. But the housing 42 and the rotary shaft
The relative relationship of 35 is the same, so any of them may be used. Further, a plurality of rotary dampers, for example, a pair of rotary dampers may be used to buffer the swing of the monitor camera in a plurality of directions.

[Effect of the Invention] As described above, the rotary damper according to the first aspect is a plate body that abuts the projecting wall portion and the wall surface of the hollow portion that correspond to the shaft that penetrates the cylindrical hollow portion in the housing of the damper main body. Since the hollow part is divided into two chambers by and the flow path of the throttle device part equipped with the variable throttle valve is directly connected, and the viscous fluid is enclosed in the hollow part and the flow path, the rotational energy of the housing or shaft of the damper main body is By absorbing the variable force with the resistance of the variable throttle, the swinging motion can be buffered as it is without converting it into a linear motion, and a pressure accumulating chamber that absorbs the volume change of the viscous fluid is provided in communication with the flow path of the throttle device. Therefore, there is an effect that the expansion energy of the viscous fluid due to a change in the outside air temperature can be absorbed and the housing or the like is not damaged.

Further, in the vibration control device for a crane monitor camera according to claim 2, the housing or shaft of the rotary damper according to claim 1 is connected to the mounting base that is hung up and down in the vicinity of the boom tip of the crane. It is possible to absorb the sway generated by the monitor camera hung on the boom of the crane with a simple mechanism without using a weight, etc., so that the hook control can always be maintained in a stable state, and the inflow and outflow of the damper main body can be performed. Since the hole and the inflow / outflow port of the expansion device portion are directly connected, there is an effect that the external pipe is not required and the device can be made compact.

[Brief description of drawings]

FIG. 1 is a sectional view showing a rotary damper according to the present invention in a direction perpendicular to a housing and a shaft, and FIG. 2 is a sectional view showing the rotary damper in a direction along the housing and the shaft. Is a horizontal sectional view of the diaphragm device, FIG. 4 is an enlarged partial perspective view showing a vibration control device for a crane monitor camera using the rotary damper shown in FIGS. 1 to 3, and FIG. 5 is a side view of the same. FIG. 6 is a conceptual diagram of a damper used in a wheel support mechanism of an automobile, an aircraft, etc.
FIG. 8 is a conceptual diagram of a damper used for shock absorption of a carrier and the like, and FIG. 8 is a conceptual diagram showing an example in which the damper of FIG. 6 is used for cushioning a swinging motion. 30: Boom, 31: Monitor camera device 32: Hook, 33: Rotary damper 34: Monitor camera body 35: Rotating shaft, 42: Damper body housing 43: Variable throttle valve, 44: Throttle device housing 46: Hollow Part, 49: Projecting wall 50: Vane plate, 51: Oil (viscous fluid) 52, 53: Inlet / outlet hole, 54: Accumulation chamber 60: Flow path, A, B: Room

 ─────────────────────────────────────────────────── ───Continued from the front page (56) References JP 55-26381 (JP, Y2) JP 60-59740 (JP 616-175639) The specification and drawings attached to the application Micro film (JP, U) of the contents

Claims (2)

[Claims] 1. A housing comprising a cylindrical hollow portion having both ends blocked therein, and a shaft penetrating the hollow portion along the axis of the hollow portion, and extending over the entire axial length of the hollow portion. The housing is provided with a projecting wall portion projecting and a projecting end abutting against the side surface of the shaft, and a plate body that abuts the wall surface of the hollow portion in the entire axial direction is provided on the shaft to provide two chambers in the hollow portion. A damper main body that is divided into two chambers, each of which has an inflow / outflow hole that opens to the outside of the housing, and a flow path inside the housing, and a variable throttle valve that acts as a resistance against the flow of the viscous fluid. A pressure accumulating chamber that faces the flow path and that absorbs a volume change of the viscous fluid is provided in communication with the flow path, and two inflow / outflow ports of the flow path are opened outside the housing. Diaphragm device The housing of the expansion device is mounted on the outer peripheral surface of the housing of the damper main body, and the two inflow / outflow ports of the flow path of the expansion device are directly connected to the inflow / outflow holes, and the damper main body part A rotary damper that encloses a viscous fluid in the hollow and in the flow path of the expansion device and absorbs the rotational energy of the housing or shaft of the damper main body by the resistance force of the expansion valve. 2. The mounting base is hung up and down in the vicinity of the boom tip of the crane, and is mounted on the mounting base.
Vibration control device for a crane monitor camera, which is formed by connecting the housing or shaft of the rotary damper of.