Technical report

“Safe­ty at work — how can machine tools and sys­tems oper­ate safe­ly and effi­cient­ly?” For a while now, sen­sors are not only a mat­ter of process con­trol — today one of their pri­ma­ry tasks is to link process­es togeth­er. With its exten­sive range of Safety@work prod­ucts, Leuze elec­tron­ic opti­mizes col­lab­o­ra­tion between man and machine: sen­sor and con­trol sys­tems, like those of the RSL 400 safe­ty laser scan­ner, can be inte­grat­ed intel­li­gent­ly into the process­es per­formed by machines and safe­guard these machines in a reli­able and tam­per­proof man­ner. At the same time, the process­es are struc­tured effi­cient­ly and cost-effectively.

Machining work pieces

In machin­ing cen­ters, parts of var­i­ous mate­ri­als are machined, turned, and drilled. The pre­req­ui­site for pro­cess­ing work pieces in com­plex machin­ing cen­ters with a high degree of pre­ci­sion is hav­ing the right tool avail­able for each work step. In addi­tion to check­ing whether the tool is present and iden­ti­fy­ing it, the drill or milling cut­ter must also be mon­i­tored for tool break­age. Induc­tive switch­es or cam­era-based code read­ers clear­ly iden­ti­fy whether the cor­rect tool is mount­ed for the respec­tive pro­cess­ing step. Focused laser pho­to­elec­tric sen­sors can — thanks to their very small light spot — reli­ably check whether even the small­est drills or milling cut­ters are intact.

Increased level of automation

Indus­tri­al robots, which can per­form a large num­ber of swiv­el and grip­ping move­ments in a very short peri­od of time, are often used for auto­mat­ed load­ing and unload­ing of machine tools. Their move­ment zones must be reli­ably pro­tect­ed against access over a large area. Before a robot picks up a part, the part must be unique­ly iden­ti­fied to ensure that the cor­rect pro­cess­ing step is car­ried out. This is done using the DCR 200i cam­era-based code read­er. The DCR 200i is a read­er used to detect and iden­ti­fy Data Matrix codes. The fast imager, inte­grat­ed high-per­for­mance LED illu­mi­na­tion, as well as high res­o­lu­tion in com­bi­na­tion with a very high depth of field guar­an­tee reli­able decod­ing, even with fast process­es and high object speeds.

Safe­ty-relat­ed mon­i­tor­ing of machines and sys­tems Safe­ty laser scan­ners such as the RSL 400 from Leuze elec­tron­ic are used for the safe­ty-relat­ed mon­i­tor­ing of areas in and around machines and sys­tems. A max­i­mum oper­at­ing range, robust oper­a­tion and sim­ple han­dling are cru­cial here. The simul­ta­ne­ous mon­i­tor­ing of four pro­tec­tive fields means the work­ing area can be split up and the speed safe­ly reduced.

The RSL 400 safe­ty laser scan­ner pro­vides a solu­tion for such appli­ca­tions. Its large oper­at­ing range of 8.25 meters allows large areas to be mon­i­tored. With two par­al­lel pro­tec­tive fields and two inte­grat­ed safe­ty-relat­ed switch­ing out­puts, only one RSL 400 safe­ty laser scan­ner can also mon­i­tor two sta­tions inde­pen­dent­ly of one another.

A fur­ther option is safe­guard­ing using mul­ti­ple light beam safe­ty devices. These devices pro­vide a greater oper­at­ing range and there­fore an effi­cient solu­tion for safe­guard­ing access points over long dis­tances of up to 70 meters — even “around the cor­ner” solu­tions with mul­ti­ple mir­ror columns are pos­si­ble. Intel­li­gent prod­ucts such as the MLD 500 safe­ty light cur­tain have an inte­grat­ed laser align­ment aid for time-sav­ing and cost-effec­tive align­ment. Sim­ple con­fig­u­ra­tion by means of wiring and inte­grat­ed indi­ca­tor lights for sta­tus dis­play are pos­si­ble, even over long distances.

In-house logis­tics with auto­mat­ed guid­ed vehi­cles (AGVs) An AGV, which moves autonomous­ly and flex­i­bly in space, trans­ports blanks into the work­ing area of the robot or machine tool. On com­ple­tion of the pro­duc­tion process, the machined work pieces are col­lect­ed again. The trans­porta­tion path of the AGVs must be safe­guard­ed with safe­ty sen­sors which mon­i­tor the pres­ence of per­sons and objects. An impor­tant con­sid­er­a­tion here is the flex­i­ble adap­ta­tion of the pro­tec­tive fields to the move­ment sit­u­a­tion and the dif­fer­ent loads. In the case of the tri­an­gu­la­tion prin­ci­ple, an AGV must be equipped with two dif­fer­ent scan­ners. Unlike the con­tour nav­i­ga­tion prin­ci­ple, just one scan­ner is need­ed for safe­guard­ing and nav­i­ga­tion. This means that safe­guard­ing and data cap­ture for nav­i­ga­tion requires one sin­gle safe­ty laser scan­ner. In oth­er words, the scan­ner simul­ta­ne­ous­ly also pro­vides the mea­sure­ment data need­ed for nav­i­ga­tion. In addi­tion to that, the mea­sure­ment val­ues have an extreme­ly high angu­lar res­o­lu­tion and accu­ra­cy. This is impor­tant to pre­cise­ly deter­mine the posi­tion of the AGV.  The RSL 400 safe­ty laser scan­ner enables such a com­bined solution.