JPH0217760Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a lower limit setting device for a ram in a hot forging hydraulic press.

Prior Art The lower limit setting device of the ram (slide) in the conventional hot forging hydraulic press is as shown in Fig. 1.
A set of rotary encoders a and a are installed on both sides of the ram (slide) b, and the ram b is pressurized by the output signals of the left and right rotary encoders a and a, which are driven by the vertical movement of the ram b. The ram b is controlled by switching the hydraulic system valve (not shown).
The lower limit position of .

The signals from both rotary encoders a and a control the left and right hydraulic pumps c and c with electric/hydraulic servo control to adjust the amount of oil sent to the left and right cylinder devices d and d, thereby causing the ram to move up and down. The lower limit position of the ram b is determined by the signals from the rotary encoders a and a while parallel control is being carried out.

In such a conventional example, two sets of rotary encoders are used as detectors, and these two sets of rotary encoders are used to feedback control the hydraulic pump that drives the ram. As a result, there was a problem in that the control equipment and the hydraulic pump became extremely expensive.

Purpose of the invention The lower limit of the ram can be set accurately regardless of the inclination of the ram with a simple configuration using one set of detectors, and the hydraulic pump that drives the ram can be feedback-controlled by the detector for setting the lower limit of the ram. It is an object of the present invention to provide a device for setting the lower limit of a ram in a hot forging hydraulic press, which eliminates the need for control and reduces the cost of the hydraulic pump.

Structure of the invention The bearing axis is oriented in the left-right direction at the center of the ram that moves up and down along the upright, and the swing axis is perpendicular to the bearing axis in the front-rear direction. A freely movable bearing is provided, the middle part of the rotating shaft is supported by this bearing, and both ends of this rotating shaft are easily connected to the left and right uprights of the press machine.
A rod member is connected via a pinion, and a rod member is rotatably suspended and connected to one end of the rotating shaft, and the lower end of this rod member is connected to the input shaft of a detector such as a rotary encoder installed on the machine frame side. A detector is operated by a rod member that is connected via a rack and pinion and moves up and down as the ram moves up and down, thereby detecting the average up and down movement of the ram.

Embodiment Hereinafter, an embodiment of the present invention will be described based on FIG. 2 and subsequent figures.

In the figure, 1 is a bed, 2 is a crown, 3 is an upright, 4 is a ram that moves up and down along this upright 3, and 5 is a cylinder device that moves this ram 4 up and down, and is fixed to the crown 2. Note that this cylinder device 5 is connected to the center of the ram 4.

At the center of the ram 4 in the left-right direction, an intermediate part of the rotary shaft 6 is connected via a bracket 6a, with its axis oriented in the left-right direction, and with its axis perpendicular to this axis in the front-rear direction. It is supported so that it can swing freely around the center. Further, pinions 7, 7 are fixed to both ends of the rotating shaft 6 that are equidistant from the swing support part, and these pinions 7, 7 are fixed in the vertical direction along the left and right uprights 3, 3. It is meshed with racks 8,8.

One end of a rod member 9 is rotatably connected to one end of the rotating shaft 6 via a bearing. This rod member 9 hangs downward, and a rack 10 is provided at its lower end. 11 is a rotary encoder fixed to the bed 1, and a rack 10 of the rod member 9 is meshed with a pinion 12 fixed to the input shaft of the rotary encoder 11.

The output section of the rotary encoder 11 is connected to an electromagnetic switching section of a valve (not shown) of a hydraulic circuit connected to the cylinder device 5 that drives the ram 4.

4 and 5 show the configuration of a bracket 6a that pivotally supports the rotating shaft 6 on the ram 4. The bearing 13 that supports the rotating shaft 6 is connected to the bracket 6a via trunnions 14, 14, and the bearing shaft It is supported so as to be able to swing freely around a swing axis that is orthogonal to the bearing axis in the front-rear direction and with its center oriented in the left-right direction.

In the above configuration, the ram 4 is
When the rotary shaft 6 moves downward, the rotating shaft 6 also moves downward while rotating along the rack 8, and accordingly, the rod member 9 suspended from the rotating shaft 6 also moves downward, and the rotary encoder 11 is driven via the rack 10. The rotary encoder 11 is then
A signal is then output to the electromagnetic switching section of the valve in the hydraulic circuit, the valve is placed in the cutoff position, and the ram 4 is stopped at the lower limit position.

When the ram 4 is moved downward, if the forging material is a lumpy hot metal piece and its position is eccentric by x from the center of the ram 4, a load P is applied to the position eccentric from the center of the ram 4 by x. acts, and as a result, the ram 4 moves downward in an inclined state by the gap between the sliding parts of the ram 4 and the uprights 3, but the rotating shaft 6 has an intermediate portion that is tilted forward and backward relative to the ram 4. It is supported so that it can swing freely around the axis of direction.
This rotating shaft 6
moves up and down in parallel with the up and down movement of the ram 4, regardless of the inclination of the ram 4. Therefore, the rod member 9 suspended from the rotating shaft 6 also moves in the same manner as the center of the ram 4, regardless of the inclination of the ram 4, and the amount of movement of the center of the ram 4 is input to the rotary encoder 11.

In the above operation, the inclination of the ram 4 is only the gap between the sliding parts of the ram 4, as described above.
Moreover, since this gap is made sufficiently small, there will not be an extremely large inclination. In addition, in the case of a hot forging hydraulic press, the forging material is a lumpy hot metal piece, and there is a considerable distance between the upper surface of the lower mold and the lower surface of the upper mold even at the bottom dead center of the ram 4, Even if 4 tilts and moves downward, the lower mold will not be damaged.

Effects of the Invention Since the present invention is as described above, the lower limit of the ram 4 can be accurately set regardless of the inclination of the ram 4 even with a simple configuration using one set of detectors.
Further, the hydraulic pump that drives the ram 4 does not need to be subjected to feedback control using a detector for setting the lower limit of the ram, making it possible to reduce the cost of the hydraulic circuit control and the hydraulic pump. Further, according to the present invention, the rotating shaft 6 for driving the detector can be easily and easily mounted.
By being mechanically maintained in parallel with the pinion and moving up and down integrally with the ram 4, the movement of the rotating shaft 6 can be mechanically coupled to the detector, and the detector is moved by the movement of the ram 4. It can operate accurately according to the

[Brief explanation of drawings]

FIG. 1 is a configuration explanatory diagram showing a conventional example, FIG. 2 is a front view of the device according to the present invention, FIG. 3 is a side view, and FIG.
Figures 4 and 5 show the bracket part that pivotally supports the rotating shaft. Figure 4 is an axial cross-sectional view, and Figure 5 is a
It is a sectional view taken along the - line in the figure. 3 is an upright, 4 is a ram, 6 is a rotating shaft, 9 is a rod member, and 11 is a rotary encoder.

Claims (1)

[Scope of utility model registration request] The bearing axis is oriented in the left-right direction at the center of the ram 4 that moves up and down along the upright 3, and the swing axis is orthogonal to the bearing axis in the front-rear direction. A rotatable bearing 13 is provided, the intermediate portion of the rotary shaft 6 is supported on the bearing 13, and both ends of the rotary shaft 6 are connected to the left and right uprights 3, 3 of the press machine via a rack and pinion. A rotary encoder in which one end of a rod member 9 is rotatably connected to one end of the rotating shaft 6, the rod member 9 is suspended, and the lower end of the rod member 9 is provided on the machine frame side of the press machine. A lower limit setting device for a ram in a hot forging hydraulic press, characterized in that it is connected to the input shaft of a detector such as No. 11 via a rack and pinion.