GB1603595A

GB1603595A - Clutch

Info

Publication number: GB1603595A
Application number: GB21553/78A
Authority: GB
Original assignee: Jagenberg Werke AG
Current assignee: Jagenberg Werke AG
Priority date: 1977-09-09
Filing date: 1978-05-23
Publication date: 1981-11-25
Also published as: BE869403A; FR2402805A1; IT7869082A0; ES473219A1; DE2740658B2; DE2740658A1; DE2740658C3; IT1107924B

Description

(54) A CLUTCH (71) We, JAGENBERG-WERKE A.G., a Joint Stock Company organised under the laws of Germany (Fed. Rep.) of Postfach 1123, D-4000 Diisseldorf 1, Germany (Fed. Rep.), do hereby declare the invention for which we pray that a Patent may be granted to us, and the method by which it is to be performed to be particularly described in and by the following statement: The invention relates to a clutch.

It is known for a labelling machine to be driven by the drive of a filling machine.

However, for cleaning processes it is desirable that this connection is interrupted, since the filling machine is cleaned by flushing clear while the drive is running, whereas the labelling machine is cleaned substantially by hand. For this purpose a clutch is arranged between the drive shaft extending from the filling machine and the take-off shaft leading to the labelling machine. In known machines, this clutch is constructed as a magnetic clutch. In this case the risk exists that upon a current failure, the clutch is engaged during the manual cleaning of the labelling machine.

Great dangers for the operating personnel arise therefrom.

According to the present invention there is provided a clutch comprising driving and driven rotary clutch members one of which is displaceable into and out of driving engagement with the other by means of a double-acting, fluid pressure operated piston member adapted to be locked in its extreme positions corresponding to full engagement and disengagement of the clutch members by respective detent means arranged to be released by fluid pressure tending to move the piston member out of the respective locked position.

Preferably, the piston member is a sleeve slidably mounted in a cylinder and defining therewith two fluid pressure chambers connected to respective fluid pressure inlets, and each detent means is associated with a respective one of the inlets and comprises a plunger which is spring loaded into its locking position and adapted to be withdrawn under the influence of fluid pressure in the respective inlet.

Preferably, each plunger forms part of a piston and cylinder unit including a fluid pressure chamber arranged in the respective inlet. Additionally a restrictor may be inserted in the pressure medium supply between the fluid pressure chamber of the detent element and the fluid pressure chamber of the switching piston. The aforesaid features contribute to the fact that upon pressure loading of the piston member the locked detent means is first released against its pre-loading and only thereafter is the piston member moved by means of the pressure medium.

According to an advantageous further development of the invention, each of the two detent means in the released position actuates a respective signal transmitter. The signal transmitters may serve merely for an optical indication. However, the signal transmitters are particularly suitable for preventing operating mistakes during the cleaning of the labelling machine. It is known that labelling machines comprise an auxiliary drive which permits creeping rotation of the labelling machine during the cleaning process. This auxiliary drive must not be operated when the labelling machine is connected to the drive of the filling machine by means of the clutch.

In contrast, the actuation of the auxiliary drive must be possible when the clutch is in the disengaged state. These requirements may be reliably satisfied by means of the signal transmitters.

The invention will now be further described by way of example with reference to the drawing, which is a longitudinal section of one embodiment of clutch according to the invention.

The clutch is illustrated in the disengaged state and comprises a first rotary clutch member 2 keyed to a drive shaft 1 and a second rotary clutch member 3 mounted on a take-off shaft 4. The clutch member 3 is displaceable into and out of engagement with the member 2 by means of a doubleacting fluid pressure operated switching piston 5 in the form of a sleeve which is axially displaceable. The switching piston 5 can be locked in its extreme positions corresponding to clutch engagement and disengagement by means of detent elements 6 and 7, so that no axial movement thereof is possible.

The first clutch member 2 is fixedly connected to the shaft 1 by a key 8 and is journalled in the end of the shaft 4 by means of a bearing 10. The second clutch member 3 is connected to the take-off shaft 4 in an axilly displaceable manner by means of splines 9 and is rotatably mounted in the switching piston 5 by means of a bearing 11, the switching piston 5 and the second clutch member 3 together performing the axial movement. The two clutch members 2, 3 interengage by means of dog formations 12.

The switching piston 5 is constructed as a double-acting fluid pressure operated switching piston with a cylinder chamber 13 on the one side and a cylinder chamber 14 on the other side. The cylinder chamber 14 is in communication with a pressure medium supply 15, and the cylinder chamber 13 is in communication with a pressure medium supply 16. The detent element 6 is arranged in the pressure medium supply 15 and the detent element 7 is arranged in the pressure medium supply 16. The detent elements 6 and 7 engage radially from outside in a respective bore 30 and 29, of the switching piston 5. In detail the detent element 6 consists of a plunger 17, a pressure chamber 18, a piston 19, a compression spring 20, a contact pin 21 and a signal transmitter 22.

Correspondingly, the detent element 7 comprises a plunger 23, a pressure chamber 24, a piston 25, a compression spring 26, a contact pin 27 and a signal transmitter 28.

The apparatus operates as follows: The clutch is used to connect the drive shaft of a filling machine to the driving shaft of a labelling machine. For the purpose of engaging the clutch (the disengaged state is illustrated) compressed air is supplied through the pressure medium supply 15 to the cylinder chamber 14. On the way to the cylinder chamber 14 the compressed air passes first through the pressure chamber 18, a flow restrictor being arranged between the pressure chamber 18 and the cylinder chamber 14. Therefore the compressed air first acts upon the piston 19 and the plunger 17 is moved against the pre-loading of the compression spring 20, so that the bore 30 in the switching piston 5 is released and an axial displacement (engagement of the clutch) is possible. In the engaged condition the compression spring 26 urges the plunger 23 into the bore 29, since no counter pressure prevails in the pressure chamber 24. The reverse movement is obtained upon disengagement of the clutch, compressed air being guided through the pressure medium supply 16 and the detent element 7 being moved radially outwardly again against the compression spring 26; thereafter the pressure medium moves the switching piston 5 again axially to the right to the disengaged position.

Even in the case of operating mistakes or upon failure of the pressure medium the operating personnel is not at risk, since only one defined manner of working of filling machine and labelling machine is possible because of the detent elements. In the engaged state, only the drive of the filling machine is effective. This state is indicated by the signal transmitters in that a signal is delivered when the contact between the contact pin 21 and the signal transmitter 22 is closed, whereas simultaneously, when the plunger 23 is retained in the bore 29, the contact between the contact pin 27 and the signal transmitter 28 is interrupted. This switching state cannot change when the pressure medium supply fails. In the disengaged state (as illustrated in the drawing) the auxiliary drive of the labelling machine (creeping motion) and the drive of the filling machine may be operated independently of each other, so that cleaning is possible. An optical indication is ensured in this case also by the contact between the contact pin 27 and the signal transmitter 28. In the intermediate position, that is to say upon axial displacement of the switching piston 5, both signal transmitters 22 and 28 deliver a signal. This double signal is utilised in such a manner that only the auxiliary drive of the labelling machine can be operated. This prevents hazards for the operating personnel arising during the change-over phase.

WHAT WE CLAIM IS: 1. A clutch comprising driving and driven rotary clutch members one of which is displaceable into and out of driving engagement with the other by means of a double-acting, fluid pressure operated piston member adapted to be locked in its extreme positions corresponding to full engagement and disengagement of the clutch members by respective detent means arranged to be released by fluid pressure tending to move the piston member out of the respective locked position.

2. A clutch as claimed in claim 1, wherein the piston member is a sleeve

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. of one embodiment of clutch according to the invention. The clutch is illustrated in the disengaged state and comprises a first rotary clutch member 2 keyed to a drive shaft 1 and a second rotary clutch member 3 mounted on a take-off shaft 4. The clutch member 3 is displaceable into and out of engagement with the member 2 by means of a doubleacting fluid pressure operated switching piston 5 in the form of a sleeve which is axially displaceable. The switching piston 5 can be locked in its extreme positions corresponding to clutch engagement and disengagement by means of detent elements 6 and 7, so that no axial movement thereof is possible. The first clutch member 2 is fixedly connected to the shaft 1 by a key 8 and is journalled in the end of the shaft 4 by means of a bearing 10. The second clutch member 3 is connected to the take-off shaft 4 in an axilly displaceable manner by means of splines 9 and is rotatably mounted in the switching piston 5 by means of a bearing 11, the switching piston 5 and the second clutch member 3 together performing the axial movement. The two clutch members 2, 3 interengage by means of dog formations 12. The switching piston 5 is constructed as a double-acting fluid pressure operated switching piston with a cylinder chamber 13 on the one side and a cylinder chamber 14 on the other side. The cylinder chamber 14 is in communication with a pressure medium supply 15, and the cylinder chamber 13 is in communication with a pressure medium supply 16. The detent element 6 is arranged in the pressure medium supply 15 and the detent element 7 is arranged in the pressure medium supply 16. The detent elements 6 and 7 engage radially from outside in a respective bore 30 and 29, of the switching piston 5. In detail the detent element 6 consists of a plunger 17, a pressure chamber 18, a piston 19, a compression spring 20, a contact pin 21 and a signal transmitter 22. Correspondingly, the detent element 7 comprises a plunger 23, a pressure chamber 24, a piston 25, a compression spring 26, a contact pin 27 and a signal transmitter 28. The apparatus operates as follows: The clutch is used to connect the drive shaft of a filling machine to the driving shaft of a labelling machine. For the purpose of engaging the clutch (the disengaged state is illustrated) compressed air is supplied through the pressure medium supply 15 to the cylinder chamber 14. On the way to the cylinder chamber 14 the compressed air passes first through the pressure chamber 18, a flow restrictor being arranged between the pressure chamber 18 and the cylinder chamber 14. Therefore the compressed air first acts upon the piston 19 and the plunger 17 is moved against the pre-loading of the compression spring 20, so that the bore 30 in the switching piston 5 is released and an axial displacement (engagement of the clutch) is possible. In the engaged condition the compression spring 26 urges the plunger 23 into the bore 29, since no counter pressure prevails in the pressure chamber 24. The reverse movement is obtained upon disengagement of the clutch, compressed air being guided through the pressure medium supply 16 and the detent element 7 being moved radially outwardly again against the compression spring 26; thereafter the pressure medium moves the switching piston 5 again axially to the right to the disengaged position. Even in the case of operating mistakes or upon failure of the pressure medium the operating personnel is not at risk, since only one defined manner of working of filling machine and labelling machine is possible because of the detent elements. In the engaged state, only the drive of the filling machine is effective. This state is indicated by the signal transmitters in that a signal is delivered when the contact between the contact pin 21 and the signal transmitter 22 is closed, whereas simultaneously, when the plunger 23 is retained in the bore 29, the contact between the contact pin 27 and the signal transmitter 28 is interrupted. This switching state cannot change when the pressure medium supply fails. In the disengaged state (as illustrated in the drawing) the auxiliary drive of the labelling machine (creeping motion) and the drive of the filling machine may be operated independently of each other, so that cleaning is possible. An optical indication is ensured in this case also by the contact between the contact pin 27 and the signal transmitter 28. In the intermediate position, that is to say upon axial displacement of the switching piston 5, both signal transmitters 22 and 28 deliver a signal. This double signal is utilised in such a manner that only the auxiliary drive of the labelling machine can be operated. This prevents hazards for the operating personnel arising during the change-over phase. WHAT WE CLAIM IS:

1. A clutch comprising driving and driven rotary clutch members one of which is displaceable into and out of driving engagement with the other by means of a double-acting, fluid pressure operated piston member adapted to be locked in its extreme positions corresponding to full engagement and disengagement of the clutch members by respective detent means arranged to be released by fluid pressure tending to move the piston member out of the respective locked position.

2. A clutch as claimed in claim 1, wherein the piston member is a sleeve

slidably mounted in a cylinder and defining therewith two fluid pressure chambers connected to respective fluid pressure inlets, and each detent means is associated with a respective one of the inlets and comprises a plunger which is spring loaded into its locking position and adapted to be withdrawn under the influence of fluid pressure in the respective inlet.

3. A clutch as claimed in claim 2, wherein each plunger forms part of a piston and cylinder unit including a fluid pressure chamber arranged in the respective inlet.

4. A clutch as claimed in any one of the preceding claims wherein each detent means is associated with a respective signal transmitter adapted to emit a signal when the detent means is released.

5. A clutch substantially as herein described with reference to and as illustrated in the accompanying drawings.