JPS62114742A - Driving device for ram of heading machine - Google Patents

Abstract

PURPOSE:To set optionally a moving speed in one reciprocating motion of a ram by using a non-circular gear for a pair of gears which are engaged to each other, of a gear train, at the time of bringing the ram to which a punch has been installed, to a reciprocating motion through a crank shaft by driving the gear train. CONSTITUTION:A crank shaft 5 is driven to rotate through a gear train A by a driving shaft 3, and a ram 1 in which a punch 2 has been installed to the tip is brought to a reciprocating motion. In this case, a work W is hit and pressed, and brought to heading forming between dies which have been installed to a frame 6 so as to be opposed to the punch 2. In a heading machine of this constitution, a pair of gears 11, 12 which are engaged to each other, of the gear train A are formed by a non-circular gear, and the crank shaft is rotated at a non-equal speed. By setting suitably a shape of these gears 11, 12, a moving speed in one reciprocating motion of the ram 1 can be set optionally, and it can become an optimum one by a shape and a quality of the work W to be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention allows a ram with a punch attached to its tip to be moved forward by the driving force of a crankshaft, thereby allowing a die attached to a frame to face the punch. The present invention relates to a ram drive device in a forging machine that presses a workpiece between the forging machines and performs forging.

Conventional technology The most commonly used method for driving the ram in a heading machine is the conventional crank drive method, in which the crankshaft is bent to create a freely slidable ram in the frame. It is connected to the crank via a connecting rod, and the crankshaft is also connected to a drive shaft driven by a motor via four rows of teeth.The crankshaft is continuously rotated in one direction, and the ram is rotated every rotation. Is it something that makes one round trip?
In conventional drive systems, the crankshaft rotates at a constant speed as the drive shaft rotates, so the ram moves forward from the rear dead center position to the front dead center position and presses the workpiece, and the ram moves forward at the front dead center position. It follows a symmetrical movement path during the backward stroke returning from the point position to the end dead center position.

At this time, the moving speed of the ram changes in a constant sine curve, with the speed being 0 at the rear dead center position and the one-stroke dead center position, and reaching the maximum value at an intermediate position.

Problems to be Solved by the Invention By the way, in the process of pressing the workpiece, while the ram is retracting, a new workpiece is transferred to the front of the die using a chuck or the like, and the ram moves toward the front dead center position. When the punch moves forward and pushes the workpiece a little into the forming hole of the die, the chuck releases the workpiece and retreats from the oil surface of the die, and the punch presses the workpiece as the punch continues to move forward. In order to retract the chuck with enough time to avoid interference between the punch and the chuck, the punch should hit the workpiece and push it into the forming hole a little, then move it to front dead center]8
It is desirable to take a longer time to reach this point, but simply increasing the time will also increase the time required for one round trip of the ram, which will reduce production efficiency. be. In addition, when forging a workpiece by upsetting it with a punch, the optimum heading speed depends on the shape and material of the workpiece to be formed, and the optimum heading speed is not uniform, but depends on the type of workpiece to be formed. By selecting the right material, it is possible to obtain a product of extremely high quality.Furthermore, when considering the wear of punches and dies, generally speaking, the slower the forging speed, the more effective it is in preventing wear.

The present invention has been completed in view of the above points, and
The moving speed of the ram can be set arbitrarily so that the time required for one reciprocation of the ram remains constant, allowing enough time for the chuck to retreat, or the forging speed can be adjusted arbitrarily. The purpose is to provide a ram drive device.

Means for Solving the Problems In order to achieve the above object, the ram drive device in the heading machine of the present invention is equipped with a punch 2 at the tip, as shown in the basic configuration diagrams of FIGS. 1 and 2. The ram L that has been
The workpiece W is pressed between the punch 2 and the die 7 mounted on the frame 6 facing the punch 2, thereby performing heading forming. In this heading machine, the pair of gears 11.1.2 that mesh with each other in the gear train A are non-circular gears, and the crankshaft 5 is rotated at a non-uniform speed.

Function The present invention has the above-mentioned configuration, and has a drive shaft 3 and a crankshaft 5.
By making the pair of gears 11 and 12 that mesh with each other in the gear train A interposed between them as non-circular gears, even when the drive shaft 3 is rotating at a constant speed, the crankshaft 5 is rotated at a non-uniform speed. By appropriately setting the shape of the gears 11 and 12, the ram 1 can be rotated without being constrained by the ram movement speed curve when the conventional crankshaft 5 rotates at a constant speed. The movement speed during one reciprocating motion can be set arbitrarily.For example, in the forward movement of the ram 1, the punch 2 hits the work W and pushes it slightly into the forming hole of the die 7, and then moves forward at a rapid speed. By controlling the ram to move forward at a slow speed until it reaches the front dead center position, sufficient time can be taken for the chuck to retreat without changing the time required for one reciprocation of the ram 1. The heading speed can also be optimally selected depending on the type of workpiece W to be formed or by taking into account the degree of wear of the punch 2 and die 7.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 3 and 4.

This embodiment is mainly intended to provide a margin for the chuck that clamps the workpiece W to retreat from the front surface of the die 7, and as shown in FIG. Gear], 1.12, the gear 11 fixed to the drive shaft 3 divides the entire circumference into approximately 11 parts, with the first and third regions having equal diameter arc shapes, and the region between them having an arc shape. The entire circumference of the gear 12 fixed to the crankshaft 5 is divided into approximately 4 areas, and the gear 12 is shaped like a cocoon as a whole with a concave central part. It is formed into a lemon shape as a whole by making an arc shape with equal diameter and a region in between with the center part of the arc shape protruding, and the details of the radius of the pitch circle of both gears 11 and 12. The numbers 1 and 1 are shown in the table below.

However, in this table, θ is a counterclockwise angle based on the position S of the driving side gear 11, and φ is a clockwise angle based on the position t of the driven side gear 12. There, respectively 0° ~ 18o.

The range of 180' to 36° is symmetrically the same as the range of 0° to 180'', so its description is omitted.

Next, the operation of this embodiment will be explained.

@ When Jfl11.12 are engaged in the state shown in Fig. 3, the ram 1 is at the rear dead center position, and when the drive shaft 3 is rotated counterclockwise from this state, it is fixed to the drive shaft 3. The gear 11 fixed to the crankshaft 5 rotates counterclockwise, and the tooth H112 fixed to the crankshaft 5 rotates clockwise. With this rotation, the ram 1 advances toward the front dead center position, and both gears 1
1. ．． When gear 12 has rotated 180 degrees, ram 1 reaches the front dead center position, and with the subsequent rotation of both gears 11 and 12, ram 1 retreats toward the rear dead center position, and when gear 5 and gear 11 and 12 have rotated once, the ram 1 reaches the front dead center position. l returns to its original rear dead center position.

Here, since the gear 11 is formed in a cocoon shape and the gear 12 is formed in a lemon shape, the crankshaft 5 rotates at a non-uniform speed, and the movement characteristics of the ram I due to 2 ft are shown in Fig. 11. When expressed in a graph with the rotation angle of the gear 11 on the horizontal axis and the vertical axis representing the rotation angle of the gear 11, the characteristic is as shown by a curve X.

If we compare this by 1 with the curve Y, which is a sine kerf when the crankshaft 5 rotates at a constant speed, the ram 1 moves forward from the rear dead center position d until it reaches the intermediate position, which is the same as the curve Y.
From there, the punch 2 moves forward at a high speed between the positions where it hits the transferred workpiece W on the curved surface of the die 7 and pushes the workpiece W into the forming hole a little, and from this pushing position it reaches the front dead center position 0. The vehicle moves forward at a slow speed, and when it reaches the vicinity of the front dead center position C, it becomes extremely slow, and when it retreats from the front dead center position C until it reaches the intermediate position, it becomes the same as the curve Y, and from there While returning to the rear dead center position d, it is confirmed whether the vehicle moves backward at a fast speed at first and then at a slower speed as it approaches the rear dead center position a.

As is clear from this graph, in this example, the ram 1
During one reciprocating motion of This allows the operator to evacuate the vehicle with plenty of time to spare.

Note that the ram 1 moves from the pushing position ib of the work W to the front dead center position mc.
By setting the time required to move forward to the same value as the time required on curve Y, the time required for one round trip of the ram 1 can be shortened.
It is possible to increase the speed and increase production efficiency, and if the time required for one round trip of the ram 1 is the same as the time required for curve Y, and the fact that there is a margin for the retraction time of the chuck can be taken advantage of. , the thickness of the chuck can be increased, making it possible to firmly hold and transport the workpiece W.

Further, in this embodiment, the forward speed of the ram l becomes extremely slow near the front dead center position C, and it takes a long time to press the workpiece W near the front dead center position C.
can be molded to precise dimensions.

As described in detail, according to the present invention, the moving speed of the ram during one reciprocating motion can be arbitrarily set. This allows sufficient time to be taken, and as a result, it is possible to shorten the time required for one round trip of the ram, allowing the heading machine to operate at higher speeds and improving production efficiency. Furthermore, the forging speed can be selected optimally depending on the type of work to be molded or by taking into account the degree of wear of punches and dies.

[Brief explanation of drawings]

FIG. 1 is a plan view showing the basic configuration of the present invention, FIG. 2 is a front view thereof, FIG. 3 is a front view of a non-circular gear according to an embodiment of the present invention, and FIG. 4 is a front view of the present embodiment. 3 is a graph showing the movement characteristics of the ram in FIG.

Claims (1)

[Claims] By reciprocating a ram with a punch attached to its tip by the driving force of a crankshaft that is rotated by a drive shaft via a gear train, a workpiece is moved between the punch and a die attached to a frame facing the punch. A ram in a heading machine that performs heading forming by pressing, characterized in that a pair of mutually meshing gears of a gear train are non-circular gears, and the crankshaft is rotated at a non-uniform speed. drive device