JPH0527400Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an improvement of a control device for controlling the lowering state of a paper discharge tray in a sheet-fed rotary printing press.

[Prior art]

In sheet-fed rotary printing presses, the printed sheets are sequentially ejected and stacked onto the paper delivery tray, and the paper delivery tray automatically descends accordingly. When taking out the upper sheet, if the paper ejection tray has stopped midway, the paper ejection tray may be lowered further by manual operation, and the user is not paying attention to the descending status of the paper ejection tray. However, the user's toes or the like may become caught between the floor and the paper output table, resulting in unexpectedly serious personal injury.

[Summary of the idea]

The purpose of this invention is to eliminate such drawbacks of the conventional method at once, and uses a descending stop position detector to detect when the paper discharging tray has descended to a descending stop position that is higher than and near the lowering limit of the paper discharging tray. The lowering stop position detector automatically stops the lowering of the paper output tray according to the detection by the lowering stop position detector, and disables the lowering operation of the paper output tray for a certain period of time after detection by the lowering stop position detector. An object of the present invention is to provide a highly effective sheet-fed rotary printing press discharge table control device that is designed to ensure the safety of workers and to alert them.

〔Example〕

Hereinafter, details of the present invention will be explained with reference to figures showing embodiments.

FIG. 1 is a cutaway side view of the main part showing the paper ejection table, in which printed sheets are captured by the gripper 5 provided on the chain 4 stretched over the sprockets 2 and 3 of the paper ejection device 1. Move the paper through chain 4 in the direction of arrow A.
As the paper moves, it is conveyed, and when it reaches the paper ejection table 11, the gripping claw 5 opens, and the paper is ejected.
The sheets are pressed against the paper rest 12 and stacked one after another on the wooden frame 14 on the stacking plate 13.

However, the loading plate 13 is suspended from above by a hanging fitting 15 and a chain 16, and is raised or lowered by a lifting mechanism (not shown in the figure), and initially the lifting limit is detected. Raise the limit switch to the LS ₁ position, and then
7 are gradually stacked up, the top level of the stacks is detected by limit switch LS ₀ , and the stack descends one by one until it reaches the position of limit switch LS ₂ , which is installed near the floor to detect the lowering limit. It has become a thing.

In addition, a limit switch LS ₃ is provided corresponding to a lowering stop position that is sufficiently safe than the lowering limit detected by limit switch LS ₂ , so that when lowering of the loading plate 13 is detected, The lowering of the loading plate 13 is automatically stopped.

FIG. 2 is a circuit diagram of the control circuit, in which A shows the relay circuit and B shows the motor circuit of the lifting mechanism, in which switch _SS1 for manual and automatic switching is manually operated to return to the recovery state; And limit switch LS ₁
~If LS ₃ is in the non-detection state as shown in the figure, relay DX2 operates and contact DX2 ₁ is turned on, so relay DU or DD operates in response to switch PU or PD being turned on, and AC power supply AC・The 3φ phases R, S, and T are applied to the motor M via the no-fuse breaker NFB and the contact UD ₁ , and the motor M rotates forward and the loading plate 13 rises, or via the contact DD ₁ . Each phase R and T are reversed and the motor M
is applied, the motor M is reversely rotated, and the loading plate 13 is lowered.

Note that if limit switch LS ₁ or LS ₂ is in the detection state due to the lifting or lowering of loading plate 13, these will be turned off, so relay DU or LS 2 will be turned off.
The DD is restored, the motor M stops, and the loading plate 13 also stops.

However, when the loading plate 13 is lowered, limit switch LS ₃ as a detector detects the loading plate ₁₃ before limit switch LS 2, and restores relay DX2 as a switching element to turn off contact DX2 ₁ . Then, in order to restore the relay DD and stop the motor M, the lowering of the loading plate 13 is automatically stopped.

On the other hand, when the limit switch LS ₃ enters the detection state, the timer DT 2 starts and turns on the contact DT 2 ₁ according to the time up after a certain period of time.
From this point on, the lowering operation of the paper discharge table 11 using the switch PD becomes effective. That is, when the paper ejection table 11 descends to the lowering stop position, it automatically stops and the timer DT2 is started.
The lowering operation of the paper discharge table 11 by the PD becomes invalid.

Therefore, according to the present embodiment, the loading plate 13 is prevented from lowering more than expected, and the safety of the workers can be ensured, and the paper output tray 11 reaches the lowering stop position and automatically stops. After, timer DT
During the fixed period of time until time 2 expires, the worker is always given time to look at the surrounding situation (especially under his/her feet), and the worker's attention can be called for. If the paper output tray 11 is automatically stopped, it will be possible to know that the current situation is close to the lowering limit.
When further descending, care can be taken not to get the feet or the like caught between the loading plate 13 and the floor. This seems to be the same even if the configuration does not provide a certain period of invalidation time for the lowering operation after the sheet discharge table 11 automatically stops at the lowering stop position. However, if a separate circuit configuration is used that does not provide a descending operation invalid time, and assuming that the switch PD is of the type that is turned on only while the switch PD is kept pressed, the paper output tray 11 will descend if the switch PD is kept pressed. Although it automatically stops at the moment it reaches the stop position, the sheet discharge tray 11 immediately descends again, leaving the operator with no time to look at the surrounding situation. In addition, when assuming an ON/OFF type switch PD, after the paper output tray 11 automatically stops at the lowering stop position, the switch PD
If the switch is turned ON again, the paper ejection tray 11 will immediately descend, and the worker will not have time to look at the surrounding situation, as described above. According to this embodiment, after the paper output tray 11 reaches the lowering stop position and automatically stops, a certain period of time during which the lowering operation is invalid is provided, so the above-mentioned problems can be avoided and the worker can be aware of the surrounding situation. You will definitely be given the time to look at it.

In addition, if switch SS ₁ is in the recovery state and limit switches LS ₂ and LS ₃ are in the non-detection state, by turning on switch PB, relay DX1 operates via contact DX2 ₂ which is on, and the contact Self-holding by DX1 ₁ and contact DX1 ₂
and operates relay DD via DX2 ₁ to cause the loading plate 13 to start descending, and at the same time, contacts DX1 ₃
This starts the timer DT1, and this state is maintained until the timer times out and the contact _DT11 is turned off. Therefore, the loading plate 13 is lowered by a certain amount according to the set time of the timer DT1.

However, in this case as well, control according to the detection operations of limit switches LS ₂ and LS ₃ is performed in the same manner as described above.

Regarding the above, if switch SS ₁ is operated and limit switches LS ₂ and LS ₃ are in non-detection state,
Relay DD operates via contact _DX21 which is in the on state until the top surface level of sheet 17 falls below a predetermined level and limit switch _LS0 is turned off.
In order to automatically lower the loading plate 13, the sheet 1
7 is always kept at a constant level.

In addition, in this case, limit switch LS ₂ and
Control in response to the detection operation of LS ₃ is performed in the same manner as described above.

In addition, there are contacts in the circuits of relays DU and DD.
DD ₂ and DU ₂ are inserted in series, each turning off the other circuit, and both operate simultaneously to prevent a short circuit from occurring between the R and T phases.

However, Relay DX2 recovery or timer
A bell or buzzer or the like may be sounded in response to the activation of DT2 to issue an alarm, and the same effect may be achieved by using a photoelectric sensor, proximity switch, etc. in place of the limit switches LS ₁ to _{LS 3} , without relying on relays. Various modifications are possible, such as configuring an equivalent circuit using semiconductor elements.

[Effect of idea]

As is clear from the above explanation, according to the present invention, when the paper output tray descends to an automatic stop position higher than the floor surface, it always stops once, and the lowering operation of the paper output tray is disabled for a certain period of time. Therefore, there is no possibility that the toes or the like may be pinched between the floor surface and the paper ejection tray, and the occurrence of personal injury can be prevented, which is highly effective in various sheet-fed rotary printing presses.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention; FIG. 1 is a cutaway side view of essential parts showing a paper discharge tray, and FIG. 2 is a circuit diagram of a control circuit, where A is a relay circuit and B is a motor circuit. 11... Paper output tray, 13... Loading plate, 15... Hanging bracket, 16... Chain, LS ₁ to LS ₃ ... Limit switch, DT ₁ , DT ₂ ... Timer, DX ₁ ,
DX ₂ , DU, DD...Relay.

Claims (1)

[Claims for Utility Model Registration] A top level detector for detecting the top level of sheets stacked on a paper output tray; a lowering limit detector for detecting that the paper output tray has descended to its lowering limit; A descending stop position detector for detecting that the sheet discharging tray has been lowered to a lowering stop position higher than and near the lowering limit; a switching element that stops the descending of the paper ejection tray in response to the detection of the paper ejection tray by the stop position detector; and a switching element that is activated in response to the detection of the paper ejection tray by the lowering stop position detector and continues the operation until time-up. A sheet discharge tray control device for a sheet-fed rotary printing press, comprising a timer for disabling a lowering operation of the sheet discharge tray.