US1736975A - Safety device for centrifugal machines - Google Patents

Description

Nov. 1929. H. J. M. c. KRANTZ 3 SAFETY DEVICE FOR CENTRIFUGAL MACHINES Filed Oct. 25, 1926 Patented Nov. 26, 1929 HUBER! J. H. C. KRANTZ, F MCHEN, GERMANY SAFETY DEVICE FOR GENTRIFUGAL MACHINES Application "filed October 25, 1926. Serial No. 144,942.

This invention relates to a .centrifu 'al machine, and particularly to a safety device therefor, the same being in the nature of an improvement upoh what isshown and described in my co-pending application Serial An object of the present improvement is to provide a safety device which will operate to prevent opening movement of themachine 19 cover until after the rotating element of the machine has ceased to move.

A more detailed object is to provide an automatically operable latch member suitably connected with the rotating element of the machine in such manner that the latch will move to unlatching position only when movement of the rotating element of the machine has stopped, or practically so.-

Other objects and'aims of the invention,

more or less specific than those referred to above, will be in part obvious and in part .pointed out in the'course of the following description of the elements, combinations, arrangements of parts and applications .of principles constituting the invention; and the scope of protection contemplated will be indicated in the appended claims.

In the accompanying drawings which are to be taken as a part of this specification, and in which I have shown merely a preferred form of embodiment of the inven- Fig. 1 is a vertical sectional view through a centrifugal machine constructed in accordance withthis invention, parts being shown in elevation, and

Fig. 2 is a top plan view of the structureseen in Fig. 1. f

In the co-pending application referred td a device is shown in which means is provided for braking the rotation of the rotatable element of a centrifugal machine co-incident with the cutting-off of driving power, and associated with means to lock the protecting and the driving power cut-off. It has been found in practice that additional means may be advantageously used for preventing open-- ;ing movement of the cover during the period of time while the brake is performing its cover closed until the brakeis thrown on .latch rod 16 is held, by the centrifugal force function of stopping the rotating member.

The mechanism shown in the present application for applying a brake co-incident with the cutting-ofi' of the driving power may be briefly described as including a lever L to which is connected a switch blade 1 for controlling the driving circuit of the motor- 2, the motor having a-pulley 3 carried at the lower end of its shaft 4 and being connected by belt 5 with the spindle 6 of the rotating element or basket G of the machine, and the basket being mounted within a casing H to which the motor 2 is connected. A brake lever 7 is connected with the lever L and with a brake band 8 which surrounds a brake drum'9 provided upon the basket G so that whenever the lever L is swungto break the driving circuit the brake band will be tightened for stopping the rotation of the basket.

The casing H has the usual hinged protecting cover 10 and the means illustrated for preventing opening movement of this cover except when the brake is on comprises a link 11 connected with the cover and with a plunger 12 so that any opening movement of the cover is accompanied by a sliding movement of the plunger in its supporting bearing 13.

Connected with the lever L is a second plunger 14 slidable in a path at right angles to the path of the plunger 12 and arranged to stand for obstructing movement of plunger 12 except when the lever L is in brake applying position, as more fully set forth in said co-pending application.

Asa simple embodiment of means comprising the present improvement the drawing illustrates the shaft 4 of the motor 2 as having connected therewith a centrifugally operated governor'devicev 15 with which is connected a latch rod 16 projecting upwardly through an opening 17 of the bearing 13 and adapted for engaging within a notch 18 provided to receive it in the plunger 12.

Whenever the motor shaft is rotating the of the governor device 15, pressed into the notch 18 so that theplunger 12 may notbe moved, and so that the protecting cover 10 is thus held against being opened. When rotation of the motor shaft ceases however, and the centrifugal force of the governor device is thus removed, the latch rod will be pulled, or be drawn, out of the notch 18 and leave the cover free to be lifted.

.It will be apparent from this disclosure that, owing to the co-operative relationship between the plungers 12 and 14, the cover must necessarily be closed before driving power can be applied to the rotor, and that the brake will at such time be released. The

notch 18 of the plunger 12 will thus of necessity be in position to receive the latchv rod when the driving power is applied. As long as the driving power remains applied the latch rod will continue in engagement within the notch. After the driving power is cutoff the latch rod will continue to stand in engagement with the notch until the basket and the motor shaft have lost their momentunli and have come practically to a stand stil If for any reason the brake should fail to be effective when the driving power is cutoff the latch rod would nevertheless continue to hold the protecting cover 10 against possible opening movement until the basket has ceased to rotate.

It will be understood that the motor 2, and the means for its control, is illustrated only in a conventional manner, and may be of any form desired, either electrical, belt driven, or otherwise.

As many changes could be made in this construction without departing from the scope of the invention, as defined in the following claims, it is intended that all matter contained in the above description or, shown in the accompanying drawings shall be interpreted as illustrative only and not in a limiting sense.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is 1. In a centrifugal machine, a rotatable member, a drive motor connected to rotate said rotatable-member, a displaceable guard for said rotatable member, a part connected with the guard to be moved thereby when the guard is displaced said part having a shoulder thereon, a bearing member within which saidpart is slidably mounted said bearing member having an auxiliary bearing opening therethrough ext-ending laterally of the direction of movement of said 'part, a device connected with the rotatable member to be rotated in concert therewith, a latch rod movable in said auxiliary bearing opening, and connections between the latch rod and said device operable by the centrifugal power generated by rotation of said device to move the latch rod within its auxiliary bearing intoengagement with said shoulder forthereby preventing displacement of the gpard during rotation of the rotatable mem- 2. In a centrifugal machine, a rotatable basket, a carrier within which said basket is rotatably mounted, an electric motor mounted upon said carrier, drive connections between the-motor and the rotatable basket by which to rotate thebasket, a displaceable guard carried by the carrier movable into and out of position for guarding the basket, a bearing member carried by the carrier in a position above the motor, a part mounted in said bearing member slidable therein in a horizontal direction and having'a shoulder thereon, con nections between said part and the guard by which to slide said part when the guard is displaced, a device connected with the motor to be rotated thereby whenever the motor is in operation said bearing member having an auxiliary bearing therein opening downwardly toward the motor, a latch rod slidable in said auxiliary bearing and extending downwardly therefrom toward the motor, and connections between the latch rod and said mentioned device operable by the centrifugal ower generated by rotation of said dev1ce or moving the latch rod upwardly through said auxiliary bearing and into engagement with said shoulder for thereby preventing displacement of the guard during operation of the motor.

3. In a centrifugal machine, a rotatable basket, a carrier within which said basket is rotatably mounted, an electric motor mountred upon said carrier, drive connections be ,the motor is in operation, said bearing member having an auxiliary bearing therein opening downwardly toward the motor, a latch rod slidable in said auxiliary bearing and extending downwardly therefrom toward the motor, and connections between the latch rod and said mentioned device operable by the centrifugal power generated by rotation of said-device for moving the latch rod upwardly through said auxiliary bearing and into engagement with said shoulder for thereby preventing displacement of the guard during operation of the motor, together with a brake for said basket, an operating handle for said brake, and means connected with said handle adapted to be moved thereby into and out of position controlling the sliding movements of said mentioned part according as said brake is applied or released.

4. In a centrifugal machine, a rotatable member, a drive motor connected to rotate said rotatable member, a displaceable guard for said rotatable member, a part connected with the guard to be moved thereby when the guard is displaced said part having a shoulder thereon, a bearing member Within which said part is slidably mounted said bearing member having an auxiliary bearing opening therethrough extending laterally of the direction of movement of said part, a latch rod movable in said auxiliary bearing opening into and out of engagement with said shoulder, and means whereby the rotatable member will move the latch rod into and out of engagement with said shoulder according to Whether the rotatable member is rotating or not, together with a brake for the rotatable member, an operating handle for said brake, and means connected With said handle adapted to be moved thereby into and out of position controlling the sliding movement of said mentioned part according as the brake is ap-. plied or released.

5. In a centrifugal machine, a rotatable member, a drive motor to rotate said rotatable member, a displaceable guard for said rotatable member, a brake for said rotatable member, a lock for said displaceable guard, means automatically operable by rotation of the rotatable member to hold the displaceable guard against displacement during rotation of the rotatable member, the combination therewith of a single manually operable lover, and con- 1 nections between the lever the motor the brake and the lock whereby operation of the motor the brake and the lock are directly controllable by movement of said single lever.

6. In a centrifugal machine, a rotatable member, a drive motor to rotate said rotatable member, a displaceable guard for said rotatable member, a brake for said rotatable memher, a lock for said displaceable guard, means automatically operable by rotation of the rotatable member to hold the displaceable guard against displacement during rotation of the rotatable member, the combination therewith of a single manually operable lever, and connections between the lever the motor the brake and the lock whereby manual movement of the lever in one direction will release the brake start the motor and lock the guard, While movement of the lever in an opposite direction will apply the brake stop the motor and unlock the guard.

In testimony whereof I aflix my signature.

HUBERT J. M. C. KRANTZ.

Images