1. What is the stroke of the press brake?
The stroke is the distance from the top dead center to the bottom dead center of the press brake.
The top dead center is the position when the slider reaches the top end.
The bottom dead center is the position when the slider reaches the bottom end.
It can be understood that the stroke of the press brake from fully opened to fully closed is the press brake stroke.
The stroke of the press brake is also the distance from the tip of the upper punch from the top of the equipment to the closing of the tip of the upper punch and the lower die.
You can refer to the figure 1 below, the “Y stroke” in the figure below is the stroke of the bending machine.
2. The importance of press brake stroke
We can know from Figure 1. The stroke of the press brake is also closely related to the toolings and daylight. In the course of daily operation. Customers will choose different toolings according to their workpieces. When the height of the toolings is different, the stroke will also change.
Customers buying a press brake often need to do a variety of workpieces. A set of tooling is usually not suitable for all workpieces. Customers need to select and purchase other toolings. When the customer chooses the toolings, we have to consider the stroke and daylight.
These two parameters are very important and affect how we choose and buy press brake toolings. However, in actual situations, the stroke and daylight are often overlooked. If these two parameters are not considered. When customers choose the height of the tooling, they often make mistakes.
It may cause the workpiece to be unable to be folded. In addition, the daylight and oil cylinder stroke of the bending machine are determined when the machine is manufactured. Customers can choose the appropriate daylight and stroke according to their needs. This can avoid wasting money.
We have explained above that the stroke from fully opened to fully closed is the stroke. Here we also briefly explain the daylight.
The daylight is the distance from the bottom of the upper beam to the top of the lower beam when the press brake is in the fully opened position. Refer to “Daylight” in Figure 1.
When choosing a mold for a bending machine, we have a few things to pay attention to:
3. How to determine the stroke of the press brake?
Now we know the stroke of the press brake is also closely related to the toolings and daylight. In the course of daily operation. Customers will choose different toolings according to their workpieces. When the height of the toolings is different, the stroke of the press brake will also change.
Some workers do not understand the relationship between the stroke and the toolings and the daylight, which can only be determined by experiments. Below we will introduce how to determine the stroke through calculation?
Here, I will give you a specific example to demonstrate how to calculate the stroke of the press brake.
We have said before,the stroke is also the distance from the tip of the upper punch from the top of the equipment to the closing of the tip of the upper punch and the lower die.
Stroke = Daylight -The total height of bottom die (height of bottom die and die holder or adaptor) – The height of top punch – The height of clamping + Depth of die notch – Plate thickness
From Figure 2, we can see the following data
The total height of bottom die: 75+26=101mm
The height of top punch: 70mm
The height of clamping: 120mm
Depth of die notch: 8/2=4mm
We assume that daylight is 400mm, plate thickness is 1mm, then the machine stroke is calculated as follows,
The stroke is 112mm
4. How do users control and adjust the stroke during use?
The use must pay attention to the adjustment stroke, and the machine must be tested before bending.
When the press brake upper die descends to the bottom, there must be a gap of plate thickness. Otherwise it will cause damage to the mold and the machine.
The press brake stroke adjustment also has electric quick adjustment and manual fine adjustment.
First check whether the ratio of the thickness of the sheet metal bending machine mold to the upper and lower modules is normal.
Generally, the slider needs to be controlled at the switching point of the stroke line. This must be noted, otherwise the mold cannot be used normally, but some people still often make such mistakes.