Page 58 - Schmalz - Vacuum Components

2_Kap_VT_EN_2016_VT_KAT 18.02.16 09:36 Seite 58
PA01019111_inh_EN.pdf
Vacuum Knowledge
Vacuum Glossary
PA01019111_inh_EN.pdf PA01019111_inh_EN.pdf

Schmalz - The Company Idle position of NO valve Minimum radius of curvature
The idle position of an NO valve refers to the position of the
The minimum radius of curvature refers to the smallest radius
that a suction cup can securely grip. For round suction cups, this
valve when it is not actuated, i.e. “open” (normally open).
Inner volume refers to a sphere, while for oval suction cups it refers to a cylinder.
The inner volume indicates the volume of the body that has to be
Operating temperature
Vacuum Knowledge evacuated during a suction procedure. For example, the inner The operating temperature is the temperature range in which a
volume of a suction cup has an effect on the evacuation time.
product can be deployed or run.
Leakage Overpressure resistance
Leakage refers to a leak within the vacuum system. This can be
Overpressure resistance refers to the maximum pressure that a
Vacuum Suction Cups caused by missing or faulty sealing elements, or by the porosity body (for example, a reservoir or vacuum filter) can resist.
of the workpiece being processed.
PNP Switching output
Load case PNP switching output refers to the configuration of a switching
output in cases where the load has a permanent connection to
Load case refers to the handling task, or the process of handling
Special Grippers a workpiece. the operating voltage source. The output transistor of the vacuum
switch connects the active device to the positive pole, allowing
Load case I – Suction cup horizontal, direction of force vertical
Load case II – Suction cup horizontal, direction of force horizontal current to flow through the consuming device.
Vacuum Grip- ping Systems Load case III – Suction cup vertical, direction of force vertical Recovery time
Low vacuum
A low vacuum describes any vacuum in which there is an absolute The recovery time is the period in which the product is not being
used or is not subject to significant work loads. The product can
pressure of 1 mbar up to atmospheric pressure (1,013 mbar). recover during this time.
Mounting Elements Examples of applications for a low vacuum include light bulbs Reference pressure
and vacuum cleaners. Vacuum handling technology also uses
values in the low vacuum range because these can be generated
Vacuum switches, for example, have a connection for reference air.
economically to create high suction power and short cycle times. Reference pressure is the pressure referred to by a sensor.
Vacuum Generators Medium vacuum Relative pressure
A medium vacuum describes any vacuum in which there is an
Relative pressure refers to the value of pressure in relation to the
absolute pressure between 0.001 mbar and 1 mbar. Medium prevalent ambient pressure. The vacuum is given using negative
vacuums are used, for example, in low-pressure gas-filled lights. values. Relative pressure has a pressure of 0 mbar as a reference
point. An absolute pressure of 400 mbar corresponds to a relative
Valve Technology Nominal flow pressure of -600 mbar. In the field of vacuum handling, it is also
common to state the values in percentages:
Nominal flow refers to the maximum flow through a certain dia -
meter (nominal diameter). The nominal flow is given in l/min or m³/h. -600 mbar corresponds to a vacuum of 60%.
Switches and Monitoring Normal force Reversing valve
Normal force is the force component acting perpendicular to a
A reversing valve is a type of changeover valve used in a blower.
surface. Every force acting on a surface can be divided into
underpressure. The valve thus controls the suction, blow-off and
normal force and shear force (see “Shear force”). Based on the The valve supplies the system alternately with overpressure and
normal force, the friction force can be calculated using the friction
neutral setting in the vacuum system.
Filters and Connections coefficient for a material pairing. The result indicates the friction Shear force
force between two surfaces, for example between a suction cup
and a workpiece. Normal force is measured in Newton [N]. Shear force is the force acting tangentially to a surface and
indicates how much friction can be transferred between the
NPN – Switching output suction cup and workpiece. Shear force is given in Newton [N].
Services NPN switching output refers to the configuration of a switching Shore hardness
output in cases where the load is connected to the positive pole
of the operating voltage source. The output transistor of the Shore hardness refers to the hardness of elastomers and plastics.
vacuum switch connects the active device through to the opera- It is a standardized material property for the hardness of materials.
Contact ting voltage, allowing current to flow through the consuming
device.

Index of Products

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PA01019111_inh_EN.pdf