JPS594275B2 - 2D movable arm member - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a two-dimensional movable arm member of a heavy object moving device that can save labor in load handling operations such as moving, assembling, and attaching/detaching heavy objects to and from machines.

Recently, a two-dimensional movable arm device that can arbitrarily move a load horizontally and vertically has been proposed and put into practical use. However, the previously proposed device, as shown in FIGS. 1 and 3, pivots the upper end of the vertical second link 2 to the tip of the horizontal first link 1. In order to form a pantograph shape, the link 1
, 2, and a horizontal third parallel to the respective links 1 and 2.
The link 3 and the fourth vertical link 4 are pivotally connected at their tips and upper ends E and C, and the rear ends and lower ends of both links 3 and 4 are pivotally connected B and Z. An arm mechanism is configured such that the length of ~4 is AD■DF2AC;CB, and this arm mechanism is attached to a vertical guide a with the rear end A of the first link 1 provided on a bracket P. In addition, the pivot portions B of the third link 3 and the fourth link 4 are slidably housed in the horizontal guide b of the 30 bracket P, and the bracket P is supported in the vertical direction by supporting the support. In addition, the support point A of the arm mechanism is connected to the take-up drum DR of the drive motor DM provided on the bracket P via the reducer GM via a chain CH to form an arm device.

'Thus, in the arm device shown in Figs. 1 and 3 above, the vertical second
Lower end FK of link 2 (a single supporting part is provided to support the load W, and when the arm mechanism is in the state shown in Fig. 2 and the load W is represented by vectors X and Y) Then, a load of y will be applied to the support point A in the vertical direction, and a load of X will be applied to the support point B in the horizontal direction.
In this arm device, the load acting on the lower end point F of the second vertical link 2 is supported by dividing it into horizontal and vertical directions, and the horizontal component of the load and its position in the horizontal direction are controlled by the horizontal guide b. However, the vertical component of the load and the vertical position are the vertical guide a
It is clear that the burden is becoming more and more burdensome.

Therefore, in order to move the load with the arm device, the motor DM winds up or unwinds the chain CH of the drum DR to move the load W up and down, and the arm device moves the load W in the horizontal direction. Since the support point B of the mechanism is freely supported by the horizontal guide b, a horizontal force is applied to the load W, but this poses a practical problem. That is, in the posture of the arm mechanism shown by the solid line in FIG. 2, near the pivot point D of the first link 1 and the second link 2,
This arm equipment? The self-weight W acts on the first link 1 as a moment represented by M in the figure, and the horizontal component force M of this moment M acts on the support point B within the horizontal guide b. As a result, the support point B of the arm mechanism is moved in the horizontal direction, causing the arm mechanism to become unstable.In other words, the arm mechanism does not remain stationary at the position shown in the figure, resulting in a so-called flow phenomenon. This phenomenon is caused by the fact that the second link 2 is 25
Even when the force is in the position , the force is generated in the opposite direction to that in the above example due to the horizontal component force. When such an arm phenomenon occurs, it becomes difficult to move the load to any horizontal position and keep it stationary, which is extremely inconvenient in practice.

Therefore, in the present invention, in order to prevent the above-mentioned arm drift phenomenon, the arm device is devised as described below.

For example, as shown in FIG. 4, a short fifth link 5 whose lower end is pivotally connected to point A at the rear end of the first horizontal arm 1 is slidably housed in the vertical guide a. At the same time, a tension spring S is stretched between the upper end G of the link 5 and a point K halfway forward of the first link 1, so that the moment M due to the weight W of the arm mechanism is absorbed by the spring. The repellent force of S was used to cancel it out.

In this case, when the angle of the first link 1 (with respect to the vertical guide a) changes, the magnitude of the moment M also changes, but the spring S also changes in response to the change in the moment M, and the arm The moment M due to the mechanism's own weight W and the moment due to the spring S are designed to almost always cancel each other out.

In order to cancel the moment M due to the arm mechanism's own weight W,...a compressed spring d or an air cylinder (
(not shown) may also be used.

In this case, instead of the link 5 in the previous example, a linker is housed in the vertical guide a, and the lower end G of the link 5'
A compression spring S5 or an air cylinder is provided between the first arm 1 and the K point to apply a compression force to the K point of the first arm 1. As described above, the arm member of the present invention can balance the horizontal component force generated at the horizontal support point that is slidably supported by the moment due to the arm mechanism's own weight, so that the arm flow can be reduced. Therefore, it is possible to easily and smoothly move the load in the horizontal direction, and to keep it stationary at the place where it has been moved.

On the other hand, in the conventional arm device, a gripping device (not shown) is fixedly provided at the lower end F of the second link 2, and this gripping device grips the load W, and the posture of the link 1 is shown in FIG. If the load W is changed as shown in FIG.

For example, when mounting a heavy workpiece on a lathe, the gripping device configured as described above changes the direction of the workpiece as the attitude of the arm 2 changes, which may impede mounting of the workpiece. Come. Note that when a heavy object is suspended b, the heavy object remains in the hanging posture regardless of the direction of the arm 2, but the heavy object often sways and is inconvenient to handle. Therefore, in the present invention, the load support part provided at the lower end F of the second link 2 is always maintained in a constant posture regardless of the attitude of the arm mechanism, and therefore the load is grasped and supported by the support part. We devised a way to maintain the load in a constant direction even when the load is on the ground.

FIG. 4 is a skeleton diagram showing the principle of the system, in which the pivot point D of the first link 1 and the second link 2 is connected to the pivot point H. I. ]
y, exhibits a right-angled triangular shape, and has a relationship of DH=AG.了 - [Short 6th link related to 了 6
On the other hand, connect both ends of the first sub-link 8, which has the same length as the first link 1, to the points H and G, and connect the ends of the first sub-link 8, which has the same length as the first link 1, to the points H and G, and connect the ends of the first sub-link 8, which has the same length as the first link 1, to the points
In this case, both ends of a second auxiliary link 9 having the same length as the second link 2 are pivotally connected to form a parallel link mechanism.
In this way, the fifth link 5 in the vertical guide a
The verticality of the elbow-shaped link r and two sub-links 8
, 9, the load is converted into the horizontality of the sixth link 6 and transmitted to the link 6. Therefore, if a load gripping device is attached to the sixth link 6, the load is transmitted regardless of the posture of the arm mechanism. The direction of can always be kept constant.

Also, in the arm mechanism mentioned earlier (see Figure 2), where does the load act? moves away from point F (in other words, if a short horizontal arm is connected to point F and a load is applied to its tip), the equilibrium state of the arm mechanism will be incomplete, and the load will become horizontal. Although movement becomes difficult, by providing the link 6, even if the position where the load is applied deviates from the point F, as long as it is on the link 6, the effect will be the same as when the load is at point F. As a result, the parallel link mechanism has a zigzag effect, so that the parallel link mechanism has the effect that the cedar shape of the tip of the cylindrical link and the position that supports the load can be arbitrarily selected.

This is the original. As described above, the arm member of the present invention can be used in a heavy object moving device to configure a movable arm device, thereby making it possible to overcome conventionally proposed arm devices. Since the arm drift phenomenon can be prevented, the horizontal movement of the load can be easily and smoothly carried out, and by providing a parallel link mechanism, the direction of the load can be adjusted regardless of the posture of the arm mechanism. Since it can be maintained constant, it is extremely useful as a two-dimensional movable arm mechanism used in heavy object handling equipment.

[Brief explanation of the drawing]

1 to 3 are skeleton diagrams showing the structure of a conventional arm device, and FIG. 4 is a skeleton diagram of an arm device according to the present invention. 1...Horizontal first link, 2...Vertical second link, 3
...Horizontal 3rd link, 4...Vertical 4th link, 5.
... 5th link, 6... 6th link, 7... Elbow-shaped link, 8, 9... Sublink, B. C. E. D.
... Pivot part, A ... Rear end of first link 1, B ...
Pivot joints between the third link 3 and the fourth link 4, a...vertical guide, b...horizontal guide, S...spring.

Claims (1)

[Claims] 1 The first, second, third, and fourth links form a pantograph-like arm mechanism, and guide the rear end of the first link and the pivot joint between the third and fourth links. In the arm member, the arm member is formed to be slidable on each of the first and second links, and a load supporting portion is formed at the lower end of the second link.
At the rear end A of the link 1, there is a short fifth part that slides within the guide.
One end of the link 5 is pivotally connected, and a spring S or an air cylinder or the like is installed between the other end G of the fifth link 5 and a position closer to the tip than the center of the first link 1. The arm mechanism is balanced in the horizontal direction, and has three pivot points in the shape of a right triangle with the other end G of the five links 5, and the pivot point of the right angle part is connected to the first link. 1 and the other pivot point of the elbow-shaped link 7 which is pivotally connected to the pivot joint D of the second link 2, and a sixth link whose rear end is pivotally connected to the lower end of the second link 2 and is oriented horizontally. A first sub-link 8 parallel to and of the same length as the first link 1 and a second sub-link 9 parallel to and of the same length as the second link 2 are pivotally connected to the tip of the link 6, respectively. A two-dimensional movable arm member for use in a heavy object moving device, characterized in that a load supporting portion provided on the sixth link 6 is kept in a constant direction regardless of the arm mechanism.