Torque Limiters
Deserti Meccanica S.r.l. (Italy)
Deserti Meccanica offers a wide range of torque limiters both mechanical and pneumatic which can satisfy every need. Deserti Meccanica uses the most modern technical and organizational systems to optimize their entire production process.
Torque limiters are both pneumatic and mechanical safety devices.
Torque limiters have become increasingly required by manufacturers and are now considered safety devices.
Their means of operation is to stop the transmission of motion between the driving device and the driven one, intervening when the connection structures are subjected to excessive overloads. This avoids major problems, such as the stopping or the breakage of the mechanical components with consequent damages to persons or plant.
LS series
Ranging from 2 to 12,000 Nm.
- Easy Use
- Solid
- Easy torque value adjustment
- Excellence price / performance ratio
- Large range
- Made in Italy
- For coaxial and parallel transmissions
- High quality construction
- High reliability
- Silent and without vibrations
- Special manufacturing on request
The “LS…” series torque limiters are safety devices that intervene to protect mechanical transmissions and respective components that are subjected to repeated overloads generated by abnormal operating conditions, thus preventing faults and damage that take the machine out of service and are usually caused by unprotected parts. Operation relies on friction that keeps materials of different consistency under tension. The friction torque limiters allow immediate release from the excess torque applied to the transmission; they do not need resetting and permit an immediate visual inspection of operating conditions.
LASS series ball/roller bearing type torque limiters
Providing accurate and precision machinery protection. Ranging from 23 to 2,000 Nm.
- High operating reliability
- Repeatability of torque value – this value does not change after being set.
- High precision adjustment
- Motion can be stopped electrically
- Motion can be stopped electrically. Synchronized reset, ( LASS…F Series ) without slipping, both in normal and in highly sensitive torque limiters.
- High speed “detachment”: only a few angled degrees of overloading are sufficient to cause the rotation that produces an electrical stop.
- Phosphated to prevent corrosion
LASS series torque limiters are safety devices protecting mechanical transmissions and relevant assemblies subjected to repeated overloading and, in any event, caused by incorrect operating conditions. Tripping of the limiters is total and definitive, causing transmission to stop mechanically and stopping the drive unit by means of an electrical device (micro switch). This device is equipped with a “Feeler” in contact with the surface of the limiter’s mobile half- coupling.
LASS SYNCRO LINE torque limiters differ from LASS LINE ones and competitors’ products thanks to a chromium plated band as a special and unique feature.
LASS series air type torque limiters
- High operating reliability
- Repeatability of the preset torque value
- Possibility of altering the torque values transmitted to suit unstable loads, as part of a machine cycle or upon starting or stopping a machine with a high dynamic cycle.
- Extremely accurate adjustment, obtainable by simple modulation of the pneumatic air supply pressure even whilst operating.
- Quick and complete disconnection by releasing the compressed air into the atmosphere, thus allowing the mechanical load to be taken instantly to ZERO (even whilst operating at maximum output) with absence of wear since dragging of the rollers on their respective seats is avoided.
- Flexibility in the choice of solutions with regard to type of operation or configuration, thus allowing the connections: shaft-shaft or shaft-pulley-pinion.
- Power-factor correction. Using the versions LASS…F/AIR, synchronous reset is obtained, passing from a state of ZERO torque to one of total synchronous traction.
These limiters are strictly derived from the “LASS” series of which they share exactly the same mechanical and performance specifications, whilst differing as regards the torque control and regulation system.
In fact, the torque can be adjusted pneumatically by altering the pressure of the compressed-air supply even during running. This system allows a very high operating speed to be achieved and proves the ideal solution as regards the problem of matching the theoretical torque for normal use of the machine with the torque necessary for the initial acceleration of the machine itself.
SGR series "backlash-free" torque limiters
Torque limiters of the “backlash-free” series are safety devices which protect mechanical components that are subject to repeated and different kinds of overload but where it is recommended to maintain a fixed and determined point of transmission.
RADIAL/TORSIONAL VALUE = 0
Function
- Any overload in the movement system caused by exceeding the predetermined torque value causes disengagement of the device, separating the driving part from the driven.
- Torque is transmitted from the hub to the pressure flange through rollers “A” lodged in special “copied” housings.
- The rollers are pushed by the moving part, transmitting the back-lash free torque limiter in both senses of rotation.
- On exceeding working torque the rollers exit their respective housing, generating the shifting of the moving component and the consequent stopping of the transmission, intercepted by an electric micro-switch which further brings about the stop (signaled) of the driving part.
Application
- The great precision of “backlash-free” torque limiters means that they can be used in all mechanical transmissions where disengagement of the drive must absolutely not cause shifting in the fixed movement points: step by step systems, automatic machines, machine tools etc.
- The various versions of “backlash-free” torque limiters- mechanical-pneumatic-laminar sprocket-for intromitters – mean that they can be applied to meet every specific need
DM/SM/PM Series torque limiters
The “DM” series torque limiters are safety devices that intervene to protect mechanical transmissions and respective components that are subjected to repeated overloading. These devices are characterized by a max. sensitivity. The solution provided by radial balls, controlled by cylindrical spiral spring, with a differentiated adjustment for every ball, allows repeatability and possibility of choice when the torque value is very high. With low speed it is possible to obtain perfect adjustment and faithful reproduction of the overload effects. Therefore, even if in principle, it is possible to use DM torque limiters also with 1400 rpm, a speed lower than 600 r.p.m. is recommended to reduce the starting and stopping inertial effects, which could cause the release of the limiters also in cases when it is not absolutely necessary.
SERIES
Free idle rotating radial ball torque limiters with the possibility of fitting the driving component by both sides, according to the requirements. They are extremely sensitive and easy-to-adjust. The re-engagement of the moving body must be carried out by the operator. The micro switch must be fitted in order to stop motion in case of release.
SM SERIES
With larger hole – Same technical and constructive features of the DM series, but with a larger hole, which allows the fitting on non standardized shafts having larger diameters.
PM SERIES
With through hole – They show the same features of the previous limiter types. They can (when the fitting on the end is not possible) be fitted in the middle of the driving shaft, that is the main shaft, with a through hole. The fitting of a micro-switch in case of release Is absolutely necessary.
FDM SERIES
With automatic timing and re-engagement – This range derives from the DM/SM series, keeping the operating, fitting and adjustment features unchanged. It differs in the automatic re-engagement every 360° and in the possibility of keeping a preset angular phase.
FSM SERIES
Same technical and constructive features of the FDM series, but with larger hole, which enables the fitting on non-standardized shafts having larger diameters.
FPM SERIES
With timing – Same technical and constructive features of the PM series; it differs in the possibility of an automatic re-engagement every 360° in case of release.
GS Series torque limiters
“GS” series torque limiters are safety devices protecting mechanical transmissions and relevant assemblies subjected to repeated overloading, due to irregular operating conditions. Tripping of the limiters is total and definitive, causing transmission to stop mechanically and stopping the drive unit by means of an electrical device (micros witch). This device is equipped with a “Feeler” in contact with the surface of the limiter’s mobile half-coupling.
These limiters are used in those cases, where the use of LASS torque limiters is not possible because of too long strokes of the sliding part. The solution is provided thanks to the use of balls which are oversize with respect to those of the LASS series. In this way very large movements can be reached. The installation of common micro switches ensures total safety.
GS series torque limiters can be supplied in three different versions according to the adjusting spring element. They are thus able to offer a wide range of controllable torque values and high sensitivity, together with appropriate holes.
FEATURES
- High operating reliability
- Repeatability of torque value – this value does not change after being set.
- High precision adjustment
- Motion can be stopped electrically
- High speed “detachment”: only a few angled degrees of overloading are sufficient to cause the rotation that produces an electrical stop
- Phosphated to prevent corrosion
OPERATING PRINCIPLE
- All “GS” series torque limiters operate on the principle entailing transmission between two half couplings via balls or rollers, which ensure that the position is maintained as they are pressed by adjustable springs.
- Any overloading exceeding the set value of the torque limiter causes a slight movement between the two half couplings which, in turn, causes the balls or rollers to come out of their seats. As a result, the half-couplings detach, the overloaded part stops rotating and the micro switch is tripped.
