Vacuum gripper usability analysis - Sintered brick handling

- Aug 20, 2019-

1 Status analysis

The company is committed to the development of logistics equipment and solutions for the wall material industry, such as steamed brick transfer and fixed point conveying equipment, sintered brick bulk transfer and fixed point transfer equipment, wheeled transfer equipment, solid bricks, and automatic transport lines. However, the actuators used (end gripping parts) are mainly scissors and parallel clamps.

Tricky handling and transfer technology is now in mature use, and the finishing of the sinter bricks – the bulk buds coming out of the kiln – is transformed into solid bricks for transport and storage, and no mature products are available to customers. .

According to the company's system design concept for the finishing of sintered bricks, the workflow is as follows:

1) Demolition: manually remove 4 or 5 pieces of the sintered brick from the flower bed, or mechanically hold the whole layer, and use external force to separate the brick layer to be removed from the lower layer of the brick layer;

2) Transfer: transport the removed brick/brick layer to the coded solid work station by using a pusher belt driven by a conveyor belt or a motor;

3) Palletizing: Use the robot or motor-driven push plate to place the brick layer neatly in the palletizing station.

Taking the above work flow as an example, the degree of adhesion of the sintered brick and the overall deformation of the brick are different, but it is inevitable that the manual demolition is most convenient and primitive, and the mechanical cannot be accurately positioned or positioned too difficult or costly; mechanical dismantling The 垛 project is being tested and should be resolved in the near future. If the transfer and palletizing are done by robots, the transfer of long strokes should be completed by using the guide rails. This technique is relatively mature and will not be described here. Then, the only thing that needs to be considered is the palletizing process.

The palletizing process is not technically difficult to implement, and existing palletizing, or clamping methods, have been described above and are aspects that may be improved or need to be improved. The direction of improvement is:

1) Integrated, with good interchangeability;

2) Lightweight and easy to operate;

3) Low cost and easy to open up the market;

4) High reliability, easy market promotion and business expansion.

From the clamping method, the mechanical clamping force point is the two sides of the long side of the sintered brick, and the reaction force provided by the self-deformation of the elastic body (for example, polyurethane) fixed on the holder generates friction against gravity. To clamp the brick layer, in order to ensure the necessary clamping force, the rigidity of the gripper plate, the strength of the scissors-type connecting member, etc. need to be considered, otherwise the problem of deformation and distortion may occur.


2 product composition

Depending on the load, the power source of the sponge suction is different: a small load, such as 240*200mm (four sintered bricks, see Figure 1) can be supplied with a vacuum generator (see Figure 2) with compressed air as a negative pressure. Device.

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Large-loaded sintered bricks 960*960mm (see Figure 3) and 720*720mm require a vacuum blower (that is, an asynchronous motor to drive a high-pressure blower for suction or suction, or an asynchronous motor to connect the vacuum pump) as a vacuum source with a power of 7.5kW. 5.5KW.


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The connection method is to use the T-screw and nut to fix the suction cup assembly on the mounting surface (manipulator end actuator), use the spring guide rod as the guide and the sponge pre-compression, the suction suction is used for normal work, and the spring compression stroke is not less than 20mm ( The thickness of the sponge is 20mm, which ensures that after the sponge is compressed, it can ensure the negative pressure provided by the hole on the adhesive surface + the sponge can reduce the surface of the adsorbed object to form a temporary confined space), the blower (see Figure 4) and the sponge suction cup assembly The hose is connected between them. Considering the long-term fatigue and reciprocation, the fatigue strength of the hose must be guaranteed. Otherwise, the air leakage and vacuum will be lower than the requirements, and the normal adsorption cannot be achieved

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The simplest vacuum adsorption system, including vacuum blowers, electromagnetic reversing valves (or pneumatic vacuum valves) and pipes, in order to ensure long-term smooth operation of the equipment, the following accessories need to be added:


1. A check valve to avoid system leakage;


2. Maintain a vacuum accumulator with a vacuum negative pressure;


3. A vacuum filter that ensures trouble-free operation of the equipment;


4. Pressure gauges that maintain system readability;


5. Vacuum switch for emergency operation;


6. Compressed air line and blow valve for auxiliary electromagnetic reversing valve;


7. Controllers that control asynchronous motors, etc.



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3 system expansion

Considering the universality and versatility of the system, if we require a sponge suction device to adapt to different bricks (solid or flower), different bricks (standard or shaped), different materials (shale or sand brick) ), different sizes (960*950, 720*700), different weights (the difference between the size of the solid enamel and the weight of the flower buds is more than 40%), in theory there are two ways to achieve:

1. Customize the smallest standard suction unit and use this minimum unit for different degrees of expansion. Taking the standard brick as an example, in order to cover the solid 垛 (19 pressure 4, 14 pressure 3) and the flower 垛 (8 pressure 3, 11 pressure 4, 6 pressure 2), only the suction tool of one brick can be selected as the module unit, even if Regardless of the positioning problem during modular splicing, when the number of bricks to be adsorbed is to a certain extent, the pipe connection and arrangement used together will be very troublesome.

2. Choose the largest suction cup assembly, configure the power, valves, lines and accessories according to the largest shape and weight, the worst on-site environment, the fastest beat, and the roughest surface – which may result in a larger amount Waste and high costs.

Recommended products (long strip units, 316mm, 442mm, 640mm, 838mm, 1234mm, 1432mm, see Figure 5), you can consider customizing and forming a series of products (here referred to as outsourcing) Sponge suction device components, blowers, etc., are connected to the robots produced by our company).


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