JPS6313064B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention is an electric resistance welded tube manufacturing line in which short materials (materials to be aligned = electric resistance welded tubes) that are cut to a fixed length by a running cutting device and moved in series at high speed are placed on an alignment table. It relates to a short material alignment device that aligns parallel materials, and more specifically,
The present invention relates to an intermittent rotation drive device that rotates an index drum of a short material alignment device.

Conventionally, the intermittent rotation drive device of the alignment device is generally configured as a so-called rotation indexing mechanism such as a Geneva mechanism or a cam mechanism. However, in either case, it is impossible to complete the indexing operation within a short time of 0.02 seconds to 0.03 seconds at the required time. Furthermore, the intermittent rotation drive device using the ratchet mechanism is approximately the first type.
It is configured as shown in the figure. That is, a ratchet gear 102 is attached to the shaft 101 of the index drum, and a pawl 103 that engages with the ratchet gear 102 is attached to a pin 1 at the tip of the cam follower shaft 104.
05, and a torsion coil spring 10
A cam 108, which is energized and attached at 6 and fixed to a rotational drive shaft 107, comes into contact with the cam follower shaft 104, and a reversal prevention pawl 109 meshes with the ratchet gear 102.

In this case, although it is possible to rapidly rotate the ratchet gear 102 by rapidly moving the pawl 103, there is no means to rapidly decelerate the ratchet gear 102, so rapid indexing is ultimately impossible. That is, if the gear is rotated rapidly, the ratchet gear 102 will overrun due to the inertia of the rotating portion, resulting in the ratchet gear 102 being advanced several teeth even though it is desired to advance only one tooth.

Therefore, the first object of the present invention is to use a driving cylinder as a power source that rapidly operates according to a command at a necessary time, and therefore satisfies the conditions for completing rapid indexing within a short time of 0.01 to 0.02 seconds. An object of the present invention is to provide an intermittent rotation drive device.

A second object of the present invention is to perform indexing operation using a rack and pinion mechanism, in which the rack is driven by a crank that reciprocates at a rotation angle of 180 degrees, and therefore the rack has a rotation angle of 90 degrees in the first half. It accelerates rapidly up to 90°, and rapidly decelerates during the second half of the rotation angle of 90°.
The indexing operation is performed smoothly, that is, there is no need to absorb or alleviate kinetic inertia, and there is no adverse effect, making it easy especially when the driving cylinder operates its forward stroke or backward stroke at a constant speed and force. It is an object of the present invention to provide an intermittent rotation drive device that can smoothly perform rapid acceleration/deceleration motion and stop without being affected by this, so that even a device with a relatively large load (rotational inertia) can perform rapid indexing without a shock.

The three objects of this invention are to attach an indexing gear to the shaft of the index drum or a shaft connected thereto, to install a rack that meshes with the indexing gear in series with the crank, and to engage the rack with the indexing gear. An intermittent rotation structure in which a means for releasing the rack is provided, a speed governor gear is attached to the shaft of a crank connected to the rack, a crank is provided on the shaft of a driving gear that meshes with the speed governor gear, and an output shaft of a driving cylinder is connected to the crank. The purpose of the present invention is to provide a driving device.

Next, the present invention will be explained with reference to illustrated embodiments.

2 to 4 show the overall structure of the short material alignment device. 1 in the figure is a running cutting device, and a guide 1a
It consists of a cutter 1c whose upper part is fed parallel to the material to be cut 4' by a feed rod 1b at a synchronous speed, and an air cylinder 1d which drives the cutter 1c. In the figure, reference numeral 2 denotes a guide through which the short pieces to be aligned 4 cut to a fixed size pass, and 3 is a magnetic sensor installed on the guide 2, which detects the distance S between the adjacent short pieces to be aligned 4, 4.
In the figure, reference numeral 5 denotes an index drum for receiving the short materials 4 to be aligned, and a large number of receiving grooves 5a are provided on the outer periphery in parallel with the axial direction at a constant circumferential pitch. In the figure, 6 is a motor that rotationally drives the index drum 5, 7 is an intermittent rotation drive device, 8 is a stepping motor that drives the pushing rod 9 installed in the index drum 5, and 10 is a motor for rotating the short materials 4 to be aligned. It is a sorting table.

Next, FIG. 5 shows the details of the structure of the intermittent rotation drive device 7, which is an embodiment of the present invention. In the figure, 71 is a rotating shaft connected to the shaft 5b of the index drum 5, and 72 is an indexing gear fixedly attached to the rotating shaft 71 with a key 70. Index gear 72
The number of teeth is made proportional to the indexing pitch of the index drum 5, that is, the circumferential pitch obtained by equally dividing the entire circumference by the total number of receiving grooves 5a, and for example, one tooth is set as the number of teeth corresponding to the indexing.

In the figure, 73 is a rack that meshes with the indexing gear, and its left end is the shaft 7 to which the governor gear 74 is attached.
Bush 7 is attached to the crank 74b formed integrally with 4a.
4c, they are rotatably connected. crank 7
The eccentricity a of 4b is set to 1/2 the pitch of one tooth, which is the number of teeth equivalent to indexing of the indexing gear 72. Also,
The right end of the rack 73 is connected to a piston shaft 75a of an air cylinder 75 for engaging and disengaging, which constitutes means for engaging and disengaging the rack 73 from the index gear 72, and a connecting rod 76.
It is connected with. 76a and 76b are connection pins.

In the figure, 77 is a driving gear that meshes with the governor gear 74, and the ratio of the number of teeth therebetween is 1:2. The crank 7 is integrated with the shaft 77a to which the driving gear 77 is attached.
7b, and an output shaft 78a of a driving air cylinder 78 is rotatably connected to the crank 77b via a bush 77c. The driving air cylinder 78 has its cylinder body attached to a bracket 79a of the frame 79 with a pin 80. The effective stroke of this driving air cylinder 78 is the same as that of the crank 77b, and thus the drive gear 77.
is configured to reciprocate through a rotation angle θ=90°.

That is, the output shaft 78a of the driving air cylinder 78
When the drive gear 77 moves clockwise on its forward stroke, the driving gear 77 rotates 90 degrees clockwise, and the governor gear that meshes with it rotates 180 degrees counterclockwise, causing the rack 73 connected to the crank 74b to move right by stroke 2a. , the indexing gear 72 that meshes with this is rotated counterclockwise by one tooth to complete the indexing.

The operating air cylinder 75 pushes up the rack 73 and maintains its meshing state with the index gear 72 while the output shaft 78a of the driving air cylinder 78 and, by extension, the rack 73 move clockwise on its forward stroke. Immediately after the forward stroke is completed, the rack 73 is pulled down to a position where it does not mesh with the indexing gear 72 until the backward stroke is completed, and the disengaged state is maintained, and after the backward stroke is completed, the rack 73 is immediately pushed up to index. The driving air cylinder 78 has a relationship that meshes with the gear 72.
There is a connection between the two. In other words, the driving air cylinder 78 performs a reciprocating stroke at the required time, and the rack 73 also performs a reciprocating stroke, but the rack 73 meshes with the index gear 72 only during the forward stroke to provide indexing feed. It performs an ejecting operation.

As the crank 74b rotates by 180 degrees, the rack 73 moves in the forward stroke, drawing a sine curve speed curve A as shown in FIG. gear 72
In the same way, the indexing operation is performed with smooth acceleration and deceleration movements.

In particular, even when the driving air cylinder 78 performs a reciprocating stroke operation with a constant force and speed, the governor gear 74 and the crank 74b are
At a rotation angle of 90°, it always decelerates, and at a rotation angle of 180°, the speed reaches zero and stops. That is, since the indexing gear 72 also stops without receiving any external force when the indexing operation is completed, rapid indexing can be performed accurately and without shock even in the case of relatively large rotational inertia.

Of course, since the driving air cylinder 78 is used as the power source, the rapid indexing operation can be completed intermittently by controlling air supply and exhaust at necessary times.

As described above, the intermittent rotation drive device of the present invention can complete rapid indexing within a short time of 0.01 seconds to 0.02 seconds.

In addition, in the intermittent rotation drive device of the present invention, the rack accelerates and decelerates rapidly as a mechanical movement characteristic and stops when the indexing operation is completed. This has the effect that rapid indexing can be performed without a shock in any case.

[Brief explanation of the drawing]

Figure 1 is a vertical sectional view of an intermittent rotation drive device using a conventional ratchet mechanism, Figures 2 and 3 are a front view and plan view of a short material alignment device, and Figure 4 is a partially cutaway view of the index drum. Plan view shown as 5th
The figure is a vertical sectional view showing the intermittent rotation drive device according to the present invention, and FIG. 6 is a diagram showing the movement characteristics of the rack. 5... Index drum, 71... Shaft, 72... Index gear, 73... Rack, 74b... Crank, 7
5... Operating air cylinder (means for engaging and disengaging the rack from the index gear), 74... Governor gear, 77... Driving gear, 77a... Shaft, 77b... Crank, 78... Driving air cylinder, 78a... Output shaft.

Claims (1)

[Claims] 1. In an intermittent rotation drive device for rotating an index drum of an alignment device, an indexing gear is attached to the shaft of the index drum or a shaft connected thereto,
A rack that meshes with the indexing gear is installed connected to the crank, a means for engaging and disengaging the rack from the indexing gear is provided, a governor gear is attached to the shaft of the crank to which the rack is connected, and a driving gear meshes with the governor gear. An intermittent rotation device for an alignment device, characterized in that a crank is provided on the shaft, and an output shaft of a driving cylinder is connected to the crank. 2 The number of teeth of the indexing gear is proportional to the indexing pitch of the index drum, and the offset position of the crank to which the rack is connected is set to 1/2 of the pitch of the number of teeth equivalent to the indexing gear of the indexing gear, and the governor gear and driving gear are The ratio of the number of teeth is 1:
2. The intermittent rotation drive device according to claim 1, wherein the drive cylinder is configured to reciprocate a crank provided on the shaft of the drive gear through a rotation angle of 90 degrees. 3. The driving cylinder and the means for engaging and disengaging the rack from the indexing gear press the rack so as to mesh with the indexing gear during the forward stroke of the driving cylinder, and from the completion of the forward stroke until the completion of the backward stroke. 2. The intermittent rotation drive device according to claim 1, wherein the intermittent rotation drive device is linked in such a manner that the intermittent rack is disengaged to a position where it does not mesh with the index gear. 4. The intermittent rotation drive device according to claim 1, wherein the means for engaging and disengaging the rack from the indexing gear is constructed by connecting the piston shaft of the engagement/disengagement operation cylinder and the rack with a connecting rod.