Background of the Invention
The invention relates to an improvement of a handling device having a linear transfer function, e.g., up-down or right left displacement.
Generally, handling devices of the linear displacement type have means for preventing rotation of a linear transfer arm. The linear transfer arm of such a conventional handling device is transferred along a guide shaft which is disposed in parallel with the arm so that rotation of the arm is prevented. In this case, there is a disadvantage in that the construction of the device is complicated.
Summary of the Invention
It is an object of the invention to provide a handling device which is simple in construction and inexpensive to manufacture.
The handling device according to the invention includes a head and a linear transfer arm having a major length dimension, and slideably mounted on the head for sliding relative thereto. Driving means mounted on the head is operable for driving the linear transfer arm to slide along its major length dimension between a retracted position and an extended position extending from the head. The driving means comprises an elongated housing mounted on the head and having a major length dimension parallel to the transfer arm length dimension and having a length extending from the head approximately equal to a length of a portion of the linear transfer arm extending from the head when the linear transfer arm is in the retracted position. Means for preventing rotation of the linear transfer arm about the major longitudinal dimension thereof comprises a member fixedly secured to the linear transfer arm at an end portion thereof, and the member extends toward the housing of the driving means and freely engages therewith for permitting translational movement of the member relative to the housing along the major length dimension of the housing and for preventing rotational movement of the member relative to the housing thereby to prevent rotation of the linear transfer arm about the major longitudinal dimension thereof.
Brief Description of the Drawings
The objects, features and advantages of the handling device according to the invention will be apparent from the specification and drawings in which:
FIG. 1 is a plan view of the handling device according to the invention;
FIG. 2 is an elevational view of the handling device shown in FIG. 1; and
FIG. 3 is an enlarged partial plan view of the handling device, and partially broken away and showing structure for preventing rotation of a linear transfer arm of the handling device.
Description of the Preferred Embodiment
The invention will be fully described with reference to a preferred embodiment shown in the drawings. In FIGS. 1 and 2, a vertical column 2 is connected with a piston rod 4 in a cylinder 3 which is provided in a base 1, and is vertically positionable according to the operation of the cylinder 3. A head 5 is attached on the top of the vertical column 2. The columns 2, cylinder 3 and piston rod 4 together comprise mounting and positioning means mounting the head on the base and operable for positioning the head along a certain direction relative to the base.
A horizontal arm 6 passes through the head 5 and is supported horizontally slidable by the head through linear motion ball bearings (not shown). On the front portion or first end portion of the horizontal arm 6, a manipulator 7 which has shifting, rotating and gripping function, is attached. A cylinder tube 9 of a cylinder 8 for driving the arm 6 is fixed to the head 5 in parallel with the arm 6. A reciprocative piston rod 10 in the cylinder tube 9 is connected with the front portion of the arm 6 through a connecting bracket 11, so that the arm 6 is horizontally transferred according to the operation of the cylinder 8.
A holding bracket 12 is fixed to the back end portion or second end portion of the arm 6. An upper roller 13 and a lower roller 14 are rotatably supported on the bracket 12 through shafts 15 and 16 respectively so that the cylinder tube 9 is between the upper and lower rollers 13 and 14. One of the shafts, e. g., the shaft 15 of the roller 13, is provided with an eccentric portion 15a, as shown in FIG. 3. By rotating the shaft 15, an interval between the rollers 13 and 14 is adjusted so that both of the rollers 13 and 14 roll on the cylinder tube 9.
Stoppers or stops 17 and 18 for defining up the forward or backward end position of the arm 6 are mounted on the head 5. Each stopper, which has a damper function, stops the stopper block 19 of the bracket 12 or the stopper block 20 of the bracket 11, so that each stopper defines the forward or extended position and backward or retracted position of the arm 6. Magnetic contactless switches 21 and 22 are mounted on the head 5. The switch 21 is operated by a magnet 23 attached on the back end of the arm 6, when the arm 6 is on the forward end portion. The switch 22 is operated by a magnet 24 attached on the front portion of the arm 6, when the arm 6 is on the backward end position.
Next, the movement of the handling device will be described, in case of gipping and setting workpieces. In the state shown in FIGS. 1 and 2, the manipulator 7 is operated and grips a workpiece which is on the waiting position. And then the cylinder 3 is operated, so that the head 5 attached on the vertical column 2 is raised. The cylinder 8 is operated and the horizontal arm 6 is linearly transferred forward, i.e., to the left in FIGS. 1 and 2, through the action of piston rod 10. In this case, keeping in contact with the cylinder tube 9, the rollers 13 and 14 supported on the holding bracket 12, which is fixed to the back end portion of the arm 6, roll along the cylinder tube 9 and are transferred forward with the horizontal arm 6. The cylinder tube 9 is put between the upper roller 13 and the lower roller 14, so that it is possible to prevent rotation of the arm 6. When the arm 6 is transferred to the forward end position of the stroke, the stopper block 19 touches the stopper 17 and the speed of the arm 6 is reduced by damping action of the stopper 17, and the arm stops later. At this time, the magnet 23 gets near the magnetic contactless switch 21 and an end signal is generated. The signal operates the cylinder 3 so that the head 5 goes down, and the manipulator 7 sets the workpiece on a predetermined position. After such gripping and setting action is finished, the arm 6 is raised and transferred backward relative to the head 5, so that it returns to the retracted position shown in FIGS. 1 and 2.
Although the invention has been described in conjunction with a handling device containing a rotation preventing means for a horizontal arm which is horizontally transferred, it is to be understood that the invention is not limited to this and it is possible to apply the rotation preventing means to an arm which is vertically transferred.
As mentioned above, in the invention, since the cylinder driving the arm is disposed in parallel with said arm transferred linearly and the cylinder operates as a guide for preventing rotation of the arm, it is unnecessary to provide another guide, whereby the handling device according to the invention is simple in construction and inexpensive to manufacture. Moreover, the cylinder 8 does not carry the weight of the piece held by manipulator 7; this weight is carried entirely by the transfer arm 6.
In case the arm is supported by linear motion ball bearings and each stopper for setting up the forward or backward end position of the arm has a damper function, it is possible to transfer the arm at high speed.