DE2609537A1 - SAFETY DEVICE FOR MACHINERY TO BE MONITORED - Google Patents

Description

PATENT LAWYERS DR. KADOR & DR. KLUNKER

Patent Attorneys Kador «Klunker Knoebelstr. 36 8 Munich 22 DR. ING. H. F. KU FNKRR (DIPt ,. [NC.)

DR. RER. NAT. U. KADOR (DIPLCHEM.)

Knoobelslrasse 36

At the Max II monument

D-8 Munich 22

Phone: 089-224164

Telegram: hello pat

Telex: 5-22903

Your reference: / Yourref .: Our reference: / Ourref .: K 11 330/7 day / Date 8. 3 · 1976

Re: / Re:

UNIMX SWITCH LIMITED
Maidenhead, Berkshire, UK

Safety device for machines to be monitored

The invention relates to a safety device for
"Closing a door, lid, or similar openable or removable guard that is normally closed around a machine or
Keep closed area that is potentially dangerous.

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British Patent 1,260,322 describes a "security device" which is a "lock unit has, which can be connected to the fixed structure of a machine, also a captive Key unit for connection to a door, cover or other protection of the machine. The two Units are designed so that they can be brought into engagement with one another and. by a Rotation of the captive key with the door closed can be locked together. The lock unit also has an electrical switching device, which is activated by the rotation of the captive key is controlled and which in turn controls the power supply to the machine, so that the machine only then is supplied with power when both units are connected together, with the power supply being switched off when the captive key is in the open position is rotated and the two units can be separated freely and the door opened and closed can be.

This known safety device is suitable for machines that become safe as soon as the power supply is switched off is. However, it is not sufficient for machines that have been switched off for some time of the current may remain dangerous as the door can be opened while the machine is running is still in a dangerous condition. For example, the machine can have rotating parts that not come to rest immediately after switching off the current, either because of the inertia of these parts or because they are slowed down gradually, as is the case, for example, in a textile mill, in order to break the fibers

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- 3 to prevent.

The invention is based on the object of a safety device to create with which these disadvantages of the known safety device are overcome will.

According to the invention, the safety device consists of a first unit, which is designed so that it can be connected to the fixed structure of a machine and contains an electrical switching device with which the power supply to the machine can be monitored, further from a second unit, which is so designed is that it can be connected to a door, a lid or a guard and which has a manually operated key device which can be moved back and forth between successive open-off and on-Stellungeη and with the first unit in and out Can be brought into engagement when it is in the OFi ¹ EN- ^ position and cooperates with the first unit in order to prevent a separation of the two units when it is in engagement with the first unit and in the out or " he employment is moved, and the key device continues to monitor the operation of the switching device when both units are in input riff stand so that the machine is only supplied with power when the key device is in the on position, a delay device, which is set in action when the key device is moved from the on to the off position, for a a movement of the key device from the off to the open position is positively prevented for a limited time «

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260953?

This limited time is chosen so that a possibly dangerous state of the machine can subside after switching off the power supply. Time can be either a predetermined time or a time that is set by a sensing device, which on the the dangerous condition of the machine.

The delay device preferably consists of a mechanical stop device, which is the key device locked in the off position and continued from a timer that is started when the key device reaches the off position and, after a certain period of time, the stop device operated and allows continued movement of the key device to the off position.

The key device can have a rotatable key which is positively locked on a second unit is held and the laterally protruding lugs through corresponding slots in the first Unit can be inserted when the key is in the open position and the corresponding Stop surfaces in the first unit cooperate to prevent removal of the key when it never plugged into the first unit and in the on position is rotated.

The key can furthermore have recesses that mate with a cylinder lock mechanism in the first unit cooperate so as to cause a loosening of the lock spindle, the lugs of the key with corresponding Grooves in the lock spindle cooperate so that the key and lock spindle can be rotated together and the

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Rotation of the lock spindle turn the operation of the electrical switching device controls. This device enables operation of the switching device prevented by anything other than the captive key of the second unit, so the protection or the door must be closed and both units locked together before the switching device can be operated to supply the machine with power.

The invention is described below with reference to the accompanying drawings, for example. Show in it:

Fig. 1 is a side view of an embodiment the invention,

FIG. 2 is a plan view of the embodiment according to FIG. 1,

Fig. 3 is a view along the line III-III in Fig. 2, and

4 shows a perspective view of the captive key and lock of FIGS . 1 and 2.

In Figures 1 to 4 of the drawings is a safety device shown, which has two separate units. Unit 1 consists of a housing 2, which surrounds a lock body 3 and is designed so that it is connected to the frame 4 of the machine to be secured can be. The other unit 5 consists of the

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Body 6 of a captive key which is designed so that it can be with a door, a lid or Guard 7 can be connected to frame 4 and a control button 8 and key 9 can be rotated and slid carries, which is designed so that it can interact with the lock body 3 to both units 1 and 5 to connect when the protection 7 is closed, as will be described below.

The control button 8 consists of a hollow cylindrical part which fits telescopically over the key body 6 and in the interior of which the key 9 is arranged axially. The key 9 is slidable and rotatable in one Bore can be introduced in the key body 6 and hollowed out at its free end, whereby a key socket 10 is formed with a cylindrical socket which engages with a locating pin 11 in the lock body 3 can be brought. Two laterally protruding, diametrically opposite key lugs 12 are formed at the outer end of the key socket 10 and are received by a pair of correspondingly formed guide grooves 13 in the key body 6 when the door 7 is open and control button 8 is released, as shown in FIG. 1. A coil spring 14 then acts between the head of the control knob and the key body to withdraw the key into the key body.

In the lock body 3 there is arranged a cylinder lock mechanism with axial pin tumblers, the one cylinder or holder 15 for the pin tumblers, which is in the Body 3 is attached and. also a cooperating cylinder or holder 16 for the pin tumblers, which is in one piece with lock spin oil 17, which is in the body 3 is rotatably arranged. The lock body 3 has a

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Front ring 18 with a conical surface that with a correspondingly conical seat 19 in the Key body can be engaged. There is a keyhole in the front wall of the front ring 20 formed, which has a central hole for receiving the key socket 10 and a pair of diametrically oppositely arranged slots 21 for receiving the key lugs 12 on the fitting 10. Die Lock spindle 17 also has a pair of diametrically opposite grooves 22 for receiving the key lugs 12 in its cylinder 16.

When the door 7 is closed, seat 19 comes on Key body 6 with front ring 18 on lock body 3 in engagement. Control button 8 can then be used against the Effect of spring 14 are depressed to insert the key socket 10 through keyhole 20. It is supported by the localization pin 11 and the key lugs 12, which pass through the slots 21 in the front ring 18 fit, guided on the lock body and comes into engagement with the grooves 22 in the cylinder 16 of the lock spindle. Key recesses 23 are along the circumference between the key approaches 12 at the end of the key version 10 arranged (see Fig. 4), and these work with the pin tumblers 24 of the cylinder lock mechanism in the lock body. 3 (Fig. 1) together to produce the Release cylinder 16 for a rotation of the lock spindle, with the key 9 being inserted into the grooves 22 Key lugs 12 acts on the lock spindle. When turning the key 9 and the lock spindle 17 move the key lugs 12 behind the areas of the front wall of the front ring 18, which between the keyhole slots 20 and form the stop surfaces to which the key lugs are attached.

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to connect the two units 1 and 5 together.

The lock spindle 17 is via a sleeve 25 with a Another spindle 26 is connected which carries cams 27, 28 of two electrical switches 29 and 30, respectively. Both switches are of the type in which the cams control the position of a bridge part that is used to bridge between The inlet and outlet of the switch are used. One switch 29 is connected so that it is the frictional connection to the controlled machine to be monitored and only lets current through when the two units 1 and 5 with the control button 8 are combined in an on position. From this on position, the control knob can be turned into a Open position can be rotated, in which the two units 1 and 5 are unlocked and key 9 from the lock body 3 is separable. Between these two positions, the control button can take an off position, in which switch 29 turns off the electricity from the machine to be monitored, in which one, however the two units 1 and 5 are still connected.

The safety device thus protects the operating personnel against injuries by applying an undercurrent the machine is only allowed when door 7 is closed and by pressing down and turning the control button is locked in the on position. A subsequent unlocking of the door automatically switches the power supply away. By providing the coded key recesses 23 on the key to operate the mechanism of the tumbler of the lock is an energization of the unprotected machine by introducing a simple object through the keyhole in the lock body.

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The above safety device is described in British Patent 1,260,322. The device according to the invention is further modified in that it includes a delay device that interlocks at Units 1 and 5 when the control knob is turned from the on to the off position switches on a time delay before the control button continues to the open position can be rotated.

The delay device consists of a solenoid operated Piston 31 'which is mounted inside the housing 2 in such a way that it lies parallel to the lock spindle 17 and cooperates with a cam plate 32, which with sleeve 25 connected is. When the solenoid is deactivated and control button 8 is in the on or off position, piston 31 is pushed out of the solenoid by a spring, so that its outer end comes into engagement with a recess 33 on the periphery of the cam plate 32 (see FIG Fig. 3) · In the on position, piston 31 has one end the recess 33, in the off position with the other end the recess into engagement, as shown in FIG. 3. Piston 31 thus prevents the control button can be turned further to the open position. the The delay device also consists of an electric switch 30 and a timer 34 * that of the Switch 30 is monitored and which in turn is activation the solenoid of the piston 3I controls. Switch 30 is operated when the control button is in the off position reached and thus the timer 34 sets in motion that in turn, the solenoid coil is supplied with power after a certain period of time. This causes piston 3I to go out the recess 33 of the cam plate 32 pulled out, whereby

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the control knob is turned to the open position and Door 7 can be opened. The predeterminable time delay the timer is chosen so that a possibly dangerous state of the machine is reduced can before it is possible to open the door.

According to a further embodiment of the invention, the timing circuit 34 of the embodiment shown can be achieved by a sensing device which senses the presence of a possibly dangerous state of the machine to be monitored and only supplies the magnet coil of the piston 31 with power when this state is reached has subsided. The sensing device can be set in motion by a switch similar to switch J> 0 , which only responds after control button 8 has been turned from its on to the off position. Alternatively, the sensing device can be continuously in operation to sense the potentially dangerous condition and to enable the solenoid to be energized only when this condition has subsided, regardless of whether the control button is in the on or off position.

It is advantageous that a failure of the circuit of the solenoid prevents an energization of the solenoid, whereupon the control button remains locked in the on or off position and the two units 1 and 5 are connected stay. The safety device shown is therefore "fail-safe" in terms of its design.

It is also advantageous that the position of the cam plate 32 is of no particular importance and

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that it is preferably attached to the spindle 26 on the other side of the switches 29 and 30 of the lock body 3 can be. The solenoid operated piston 31 would then have to be relocated accordingly.

Although the embodiment shown with a locking mechanism is provided with tumblers to turn the lock spindle by introducing a simple object to prevent in the keyhole, this lock mechanism can either in the embodiment shown or any of the other embodiments described above can be omitted. This results in the Possibility of turning the lock spindle using devices other than the captive key in the key body. This may be acceptable in some non-industrial applications, such as spin dryers in the household.

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Claims (19)

- 12 claims M .j safety device, consisting of a first unit which is designed so that it can be connected to the fixed structure of a machine and which has an electrical switching device to monitor the power supply to the machine, further consisting of a second unit, the is designed so that it can be connected to a door, a lid or other protection and has a manually operated key device which can be successively adjusted between open, off and on positions and in the open position with the first unit can be engaged and disengaged and which cooperates with the first unit to prevent separation of the two units when engaged with the first unit and in either the off or on position and the key device continues to monitor the function of the switching device when both units are in engagement with each other, so that the machine e is only supplied with power when the key device is in the employment, characterized by the fact that the security device has a delay device (30, 31, 32, 34-) which when the locking device (9) is moved from the Position in the off position responds and then for a limited time prevents a movement of the key device from the off position in the open position. 609840/0726 2. Safety device according to claim 1, characterized in that that the delay device has a mechanical stop (31), which the key device (9) in the off position locked and which is operated after a limited period of time for continued movement to enable the key device in the open position. 3. Safety device according to claim 2, characterized in that the key device (9) with a movable part (17) in the first unit cooperates so that the movable part reciprocates between an open, off and on position and the electrical switching device (29) is controlled by the movement of the movable part and that the stop device has a first stop part (32) which extends from the movable part (17) is worn and a second stop part (31) i the on the first unit (1) and cooperates with the first stop part (32) to the key device (9) to be locked in the off position. 4. Safety device according to claim 3, characterized in that the key device (9) and the movable part (17) are rotatably mounted in the second or first unit (5; 1) and cooperate in this way, that they twist together unr! that the first stop part (32) on the movable part (17) is attached so that it rotates with this and that the second stop part (34-) on the first unit (1) is attached so that it can be brought into and out of engagement with the first stop member (32). 609840/0726. 5 · Safety device according to claim 4, characterized in that the first stop part (32) is directed substantially radially to the axis of rotation of the movable part (17) and that the second Stop part (31) essentially parallel to the axis of rotation of the movable part (I7) is guided and between a normal position in which it is in the Projecting level of the movement of the first stop part (32) in order to lock the latter in its off position and a release position in which it is withdrawn from the plane of movement of the first stop part is adjustable. 6. Safety device according to one of claims 2 to 5i characterized in that the stop device (31) can be actuated electrically. 7. Safety device according to claim 5 and 6, characterized characterized in that the second stop part (31) is a solenoid operated piston. 8. Safety device according to claim 7 *, characterized in that the piston (31) in Normal position is when the coil is deactivated and in the release position when it is energized. 9 safety device according to one of claims 2 to 8, characterized in that the delay device (30, 311, 32, 34-) is a time device (3 ^), which is started when the Key device (9) reaches the off position and the stop device after a predetermined period of time (31) actuated. 609840/0726. 10. Safety device according to claim 9, characterized in that the timing device (34) has an electrical timer, which electrically actuates the anchor device. 11. Safety device according to claim 9 or 3 and 10, characterized in that the Timing device (3 * 0 an electrical switch (30) which is actuated by the movement of the movable part (17) and which the timing device (34) starts when the key device (9) has reached the off position. 12. Safety device according to one of claims 9 to 11, characterized in that the Time device (3 * 0 is part of the first unit (1). 13. Safety device according to one of claims 2 to 8, characterized in that the delay device has a sensing device, which senses a possibly dangerous condition in the machine and the anchor device (3I) controls so that the key device (9) cannot be moved from the off to the on position, until the dangerous state has subsided. 14. Safety device according to claim M or 5 or one of claims 4 and 6 to 13, characterized in that the key device (9) is rotatably and slidably mounted in a key body (6) which is designed so that it is with a door (7) can be connected and the laterally protruding lugs (12) carries through 609840/0726. corresponding slots (21) in the first unit (1) are insertable when the key device (9) is in the open position and the stop surfaces cooperate in the first unit (1) to prevent the key device from being removed, when this is inserted into the first unit (1) and rotated into the off or on position. 15. Safety device according to claim 14, characterized characterized in that the lugs (12) on the key device (9) with corresponding Grooves (32) in the movable part (17) interact, the two being coupled to one another and rotatable together are. 16. Safety device according to one of claims 14 or 15 »characterized in that the key device (9) with a control button (5) is connected, which is attached to the key body (6) so that it can be telescoped thereon and is rotatable relative to it. 17 · Safety device according to claim 16, characterized in that a spring device (14) is provided in the second unit (5) to the key device (9) in a relative to To preload the key body (6) in the retracted position, in which the lugs (12) are automatically aligned in a predetermined angular orientation will. 18. Safety device according to one of claims 14 to 17, characterized in that the first unit (1) a cylinder lock mechanism 609840/0726. with a lock spindle (17) which forms the movable part and which is normally secured against rotation _T however your introduction of the key device (9) into the slots (21) of the first unit (1) is released for rotation. 19. Safety device according to claim 18, characterized characterized in that the cylinder lock mechanism is one with axial pin tumblers and the key device (9) coded Has recesses (23) which come into engagement with the pin tumblers (24) of the lock mechanism in order to to loosen the lock spindle. 609840/0726. At Blank page