JPS626945B2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention applies not only to the rising end and the descending end of the conveying rod, but also to the
The present invention relates to a conveying rod lifting and lowering device that also controls the speed and acceleration at points in between.

2. Description of the Related Art Various means have been proposed in the past for reducing the shock caused by stopping at the ascending end or descending end of a transport rod in a transfer machine, autoloader, or other transport rod lifting/lowering device. Typical examples include a method of squeezing the oil in the drive device just before the stop position, a method of installing a shock absorber at the stop position,
Alternatively, there is a method of mechanically controlling acceleration/deceleration. However, in either method, the shock can only be reduced at two points, upper and lower, and the speed and acceleration at intermediate positions where the conveyed object is attached and detached are not taken into consideration. For this reason, if the conveyed object is lightweight, the conveyed object may be displaced or fall off due to the shock during attachment and detachment.

In order to eliminate the above-mentioned drawbacks, the present invention aims to control the speed and acceleration of the transport rod in the transport rod lifting device not only at the rising end and the lowering end, but also at the conveyed object attachment/detachment position between them. shall be. In order to achieve this object, the present invention has a structure in which a crankshaft is pivotally supported on a drive arm that is reciprocatingly rotated eccentrically with respect to its rotation center, and a planetary gear is provided on this crankshaft, and the planetary gear meshes with the drive arm. A sun gear is fixedly supported with its center aligned with the rotation center of the drive arm, a roller is pivotally supported on the crankshaft eccentrically with respect to the axis thereof, and an output shaft having a groove with which the roller engages is provided. Rotatably supported,
It is characterized in that a driving joint is coupled to the output shaft, and a driven joint that engages with the conveying rod is connected to the driving joint via an intermediate joint.

In other words, in the present invention, the cycloid generating mechanism and the four-bar linkage mechanism are used as means for driving the transport rod in order to control the speed and acceleration not only at the ascending end and the descending end of the transport rod, but also at positions in between. be.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a conveying rod lifting device according to the present invention will be described in detail based on an embodiment shown in the drawings.

Fig. 1 shows a cross section of the cycloid generating mechanism in one embodiment, and Fig. 2 shows the - in Fig. 1.
A cross section taken along a line is shown, and FIG. 3 shows a four-bar linkage mechanism.

A piston-shaped rack 3 is inserted into the cylinders 2a and 2b, which are attached to the casing 1 so as to face each other on the same axis, so as to straddle these cylinders.
This rack 3 is connected to a flow path 5 formed in cylinder lids 4a and 4b that close the ends of cylinders 2a and 2b.
It is reciprocated by pressure fluid supplied from a and 5b. Reference numeral 6 denotes a presser roller that comes into contact with the upper surface of the reciprocating rack 3. A fixed shaft 8 is fixedly supported on the casing 1 by a fixed bracket 7 in a direction perpendicular to the reciprocating direction of the rack 3. A drive arm 9 is rotatably mounted on the fixed shaft 8 via a bearing, and a pinion 10 that meshes with the rack 3 is integrally connected to the drive arm 9. That is, the drive arm 9 is reciprocated and rotated via the pinion 10 by the reciprocating movement of the rack 3. A sun gear 11 is fixed to the fixed shaft 8, while a crankshaft 12 is pivotally supported on the drive arm 9 eccentrically with respect to its rotation center.
A planetary gear 13 that meshes with 1 is connected. Due to the rotation of the drive arm 9, the planetary gear 13 and the crankshaft 12 rotate (revolution) while rotating on their own axis. 14
is a bearing support that is integrated with the drive arm 9 and is rotatable with respect to the fixed shaft 8 via a bearing, and also supports the crankshaft 12. A roller (cam follower) is mounted on the crankshaft 12 eccentrically with respect to its axis.
15 are supported. As the crankshaft 12 moves, the roller 15 rotates around the axis of the crankshaft 12 and around the rotation center of the drive arm 9.

On the other hand, the fixed shaft 8 in the casing 1
On the opposite side to the side fixedly supported by the fixing bracket 7, an output shaft 16 is rotatably mounted via a bearing with its center coincident with the rotation center of the drive arm 9 (same as the center of the fixed shaft 8). Supported. Output shaft 16
A hole 17 is provided in the center of the shaft, into which the end of the fixed shaft 8 is inserted and supported via a bearing. This output shaft 16 has a groove 18 in the radial direction.
is formed, into which the roller 15 is fitted. The output shaft 16 is rotated while the roller 15 rotates due to the rotation of the crankshaft 12 of the roller 15 and the rotation of the drive arm 9 around the rotation center.
By moving within the groove 18 of the output shaft 16, the output shaft 16 is rotated while changing its speed and acceleration. If the rotation angular velocity of the drive arm 9 is constant, the rotation radius (revolution radius) of the roller 15 with respect to the center of the output shaft 16
When the rotation radius is the minimum, the rotational angular velocity of the output shaft 16 is the minimum, and when the rotation radius is the maximum, the rotational angular velocity is also the maximum. In the present invention, the amount of eccentricity of the roller 15 with respect to the axis of the crankshaft 12 and the amount of eccentricity of the crankshaft 12 with respect to the center of rotation of the drive arm 9 are set such that the rotational angular velocity of the output shaft 16 is 0 when the rotation radius is the minimum. Also, the number of teeth of the planetary gear 13 and the sun gear 11 are set.

The above is the structure of the cycloid generating mechanism, and this is combined with the four-bar link mechanism. A driving link 19a, which is a driving link of a four-bar link mechanism, is coupled to the output shaft 16. This driving link 1
9a is connected by a shaft 21 to a driving link 19b which is rotatably supported by a support member (stationary joint) 20 with its center on an extension of the center of the output shaft 16, and the two are integrally formed. Rotate and rotate. Axis 21
One end of an intermediate link (intermediate node) 22 is connected to the support member 23 by a sliding joint, and the other end of the intermediate link 22 is connected to a support member 23.
A dogleg-shaped driven link (driven joint) 24, one end of which is pivotally supported, has a central portion (bent portion) connected to the sliding joint. A roller 25 is attached to the other end of this driven link 24.
is provided, and a conveying rod 26 is supported by this roller 25. A workpiece pedestal 28 that supports a conveyed object (workpiece) 27 is provided on the conveyance rod 26 . Note that 29 is a connecting rod that is connected to an adjacent link mechanism (driven). The rotation of the driving links 19a and 19b causes the driven link 24 to swing via the intermediate link 22, and the movement of the roller 25 at its tip causes the conveying rod 26 to rise and fall. Since it is raised and lowered by the swinging driven link 24, the transport rod 26 smoothly accelerates or decelerates and stops at its lowering end and rising end. An object 27 is placed between the descending end and the ascending end of the transport rod 26.
Since there is an attachment/detachment point (transfer position) of
The four-bar linkage mechanism is designed such that when the transport rod 26 is stopped, the transport rod 26 is located at the attachment/detachment point.

FIG. 4 shows an example of the speed change of the conveying rod 26 according to this embodiment of the apparatus. As shown in this figure, the speed rises smoothly at the descending end, once reaches 0 at the conveyed object loading/unloading point, and then increases.
At the rising end, the speed smoothly drops to 0 again.

Furthermore, the roller 15 in the cycloid generating mechanism
eccentricity of crankshaft 12 and gear 1
By changing the number of teeth 1 and 13 or the specifications of the link mechanism, it is possible to freely change the upward and downward strokes of the conveying rod 26, the position of the attachment/detachment point of the conveyed object, etc.

As described above in detail based on one embodiment,
According to the conveying rod lifting device according to the present invention, the conveying rod smoothly accelerates or decelerates to a stop at the descending end and the ascending end by the crank motion, and also decelerates and stops at the conveyed object loading/unloading point by the cycloid motion. The posture of the conveyed object is stabilized throughout the cycle. This eliminates machining defects and dropping of conveyed objects due to misalignment of conveyed objects, and improves machine performance.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional view of a cycloid generating mechanism in an embodiment of the present invention, and FIG.
A line sectional view, FIG. 3 is a front view of the four-bar linkage mechanism in one embodiment, and FIG. 4 is a diagram showing changes in speed of the conveying rod in one embodiment. In the drawing, 3 is a rack, 8 is a fixed shaft, 9 is a drive arm, 10 is a pinion, 11 is a sun gear, 12 is a crankshaft, 13 is a planetary gear, 15 is a roller, 16
is an output shaft, 18 is a groove, 19a, 19b are driving links, 22 is an intermediate link, 24 is a driven link, 25
is a roller, and 26 is a conveyor rod.

Claims (1)

[Claims] 1 A crankshaft is pivotally supported on a drive arm that is driven to reciprocate and rotated eccentrically with respect to its rotation center, and a planetary gear is provided on this crankshaft, and a sun gear meshed with this planetary gear is centered around the rotation center of the drive arm. A roller is pivotally supported on the crankshaft eccentrically with respect to the axis of the crankshaft, and an output shaft having a groove with which the roller engages is rotatably supported;
A conveying rod lifting device characterized in that a driving joint is coupled to the output shaft, and a driven joint that engages with the conveying rod is connected to the driving joint via an intermediate joint.