US2029032A

US2029032A - Machine for slicing meats

Info

Publication number: US2029032A
Application number: US689187A
Authority: US
Inventors: Olsson Karl Eric
Original assignee: Individual
Current assignee: Individual
Priority date: 1933-09-13
Filing date: 1933-09-13
Publication date: 1936-01-28
Anticipated expiration: 1953-01-28

Description

Jan, 28, 1936.

K. E. OLSSON 2,029,032

MACHINE FOR SLICING MEATS Filed Sept. 13, 1933 4 Sheets-Sheet l KARL ERIC OLSSON INVENTOR BY in ATTORNEYS Jam 1936- K. E. OLSSON.

MACHINE FOR SLICING MEATS Sheets-Sheet 2 Filed Sept. 13, 1933 AM w KARL ERIC OLSSON INVENTOR t 41 ATTORNEYS v Y B Jan. 28, 1936. K, QDLSSON 2,02%32 MACHINE FOR SLICING MEATS KARL ERIC 01.55am

- INVENTOR I Q ATTORNEYS Jan. 22, 1936. E, OLSSON 2,029,022

MACHINE FOR SLICING MEATS Filed Sept. 13, l933 4 Sheets-Sheet 4 V 1 I 7/ H I I i 7 5 I j ffi I I s 79 5/ 76 60 KARL ERIC OLSSON INVENTOR ATTORNEYS Patented Jan. 28, 1936 STATE i ATENT OFFICE 10 Claims.

The present invention relates to new and improved devices in meat slicing machines of the kind provided with a knife rotatably journalled on a swingable arm or holder, and a table for the material to be sliced, the said table being movable perpendicularly to the knife path, the arm carrying the knife being mounted in one end or corner of the frame of the machine below the horizontal plane of the table, so that, when swinging the arm from the resting position to the slicing position, the knife will have a very short distance to move and the work is facilitated.

The general object of the invention is to obtain a simple and. cheap construction.

A particular object of the invention is to provide an effective knife guard for the knife-edge under the abovementioned conditions. This arrangement eliminates the risks of accidents, when operating the machine, the risks in the said devices being considerably greater than, for instance, in machines having stationary knives.

A further object is to provide in a machine having the knife arm placed and movable in the frame of the machine in the manner indicated; a device by means of which the knife is caused to rotate only when the arm is being swung downward (from the resting position to the slicing position).

Further characteristics of the invention include simplified and effective means for automatically feeding the table adapted to carry the meat toward the path of the knife under positive control of the movements of the knife arm. It may be stated in this connection that the invention also includes means for blocking the motion of the table in the opposite direction, and for releasing the blocking device when necessary.

The said and other characteristics are illustrated in the accompanying drawings, in which Fig. 1 is a front view of the machine with the knife shown partly in a raised position, and partly in dot and dash lines in a swung down intermediate position;

Fig. 2 is a top view of the front end of the machine,

Fig. 3 is a top view of the whole machine, certa n parts being cut away,

F'g. 4 is a side view, partly in section of the shaft construction by which the slicing table is actuated;

Fig. 5 illustrates details of the said construction viewed from above,

Fig. 6 is a section along the line VI-VI of Fig.

Figs. 6A, 6B are sectional detail views, taken on the line A-A of Figure 6, and show one of the table guide means. In Figure 6A, the table is in advanced position, and in Figure 6B, the table is in returned position and guide bar 22 has 5 been given a one quarter rotation by the handle H,

Fig. 7 is a detail on a larger scale of a drive and stop mechanism for the above mentioned shaft constructions partly in section and with certain parts cut away,

Fig. 8 is a front view of the coupling device for rotating the knife, certain parts being removed;

Fig. 9 is a similar front view, a cover for the coupling being removed,

Fig. 10 is a top view of the same device, the cover surrounding the same being cut away,

Fig. 11 is a section along the line XI-XI of Fig. 9 and Fig. 12 is similar to Fig. 10, but includes added detail.

In all the figures equivalent parts are indicated by the same reference numerals.

The main parts of the machine consist of a circular knife 2 rotatably journalled on a handleprovided holder or arm 4 which is swingably mounted in a vertical plane in the frame 3, and of a table 5 movable in the frame toward and from the knife and thus perpendicularly to the knife path. Table 5 is provided, in a way known per se, with clamping devices for the material to be sliced, the said clamping devices having an adjustable clamp 6 in the shape of a stirrup and fixing pins 68, 69 on the table and the stirrup respectively, the said stirrup being provided with a setting screw 6 having an adjusting handle. Moreover the table is provided with a guide and cutting edge 7. The table is gradually advanced toward the knife path by means of a feeding mechanism the movement of which is controlled by movement of the arm 4 and which will be more particularly described below. 8 indicates a plate or the like for receiving the sliced meat, and 9 indicates a detachable bottom memher.

The operating arm 4 is secured to a shaft H] which is pivotally mounted in the rear part of the frame inside the longitudinal side of the frame and below the table 5. By this arrangement a very short movement of the knife from the upper position (the resting position) to the slicing position is obtained, and thus the work is facilitated.

As, however, during this movement the knifethe slicing.

edge may be easily subjected to damage, and because due to the said position of the swinging shaft there are many more risks of accidents when manipulating this type of machine than in machineshaving the knife mounted in another way, a knife guard is provided. This guard is carried by the machine-frame or made in one piece with the machine-frame, and consists of a frame, flange or rib l I, which from the rear edge of the machine-frame first runs rearward and then in a curve upward and forward toward the front machine-frame edge. The curve is first approximately circular but then shaped in accordance with the envelope curve of the knife-edge, and thus the knife is protected from above during its motion and may in the raised (resting) position be sufiiciently drawn back within the outline of the knife guard to leave a free working space for placing meat in position upon, or removing meat from'the table. The flange i l is connected with a plate l2, which completely protects the knife from the inside (the table side). From the arm 4 extends a bar or guard arm 53 in a curve along part of the periphery of the knife, which bar with its upper edge extends a little over the knife-edge and is axially displaced a little outward relatively to theknife-edge (from the middle of the table). When the arm is swung down to the slicing position the bar avoids injury from (involuntary) grasping of the front edge of the flange H. Of course the protection bar must be so made as to not extend over the part of the knife-edge curve (about A,, of the curve) necessary for effecting If desired, a similarly shaped bar may run from the arm 4 in the opposite direction so that the risk of accidents from grasping the machine between the knife and the guard plate l2 may be prevented when the knife is being swung upward from the swung-down position. The bars may also run peripherically in the radial plane of the knife a little outside the knife-edge and, if desired, be provided with a part swung out (viewed from the table) like a curve which projects radially inward past the knife-edge. Shoulders M, I4 limit the movements of the arm 4,

and locking members H5, it are provided for locking the shoulders in the resting position and in an intermediate position for grinding, respectively.

At the guard curve H is fixed a band H such as, a wire or rope of steel or any other suitable material. As shown in Fig. 1.2, the band is wound on a roll it on a shaft l! journalled in a casing l9 located on the arm t in which casing also the knife shaft is journalled. On the shaft 20 is wedged a gear l2 which is held in its position by a stop nut 86 screwed on the threaded end of the shaft. Gear it engages another gear t3, the latter being loosely journalled on the shaft ll. The said parts are situated in a widened portion of the casing IS. A plate '54 is fixed on the shaft H and is provided with tracks 15 for rolls 55 adapted to be actuated by springs ll pressing the rolls to engage between the plate l4 and the gear 13. A spiral spring 58 is also provided and has 7 one end fixed in the casing and its other end secured to the shaft H.

When thus the arm 4 is swung downward the shaft ii and also the plate i l are rotated by the band if in the direction of the arrow so that the roll ratchet will carry along the gear 13 whereby theknife shaft is brought into rotation. Thethe'arm is being returned the spring rotates the shaft H in the opposite direction whereby'the band if is wound on the roll it. The roll ratchet is during the last mentioned movement inoperative and thus the toothed rim and the shaft remain idle. A detachable cover 8| covers the outside of the casing, and in the same is made a hole for the end of the shaft 20. This end of the shaft is provided with a bore 39 and a slot 82, adapted to receive a suitable key or crank for manual operation of the knife shaft when, for instance, the knife is to be ground.

The table 5 travels by means of guides 2! or the like located on the underside on guide bars 22 pivotally journalled in the machine-frame. The guide bars have flattened edges 22 on their rear portion of a length corresponding to the length of the guides and the bars can be turned by means of a handle H provided for each bar. By this arrangement the table in its completely returned position is adapted to be removed from the bars. A rack 23 engages a toothed wheel 23, which, prefer-ably by means of a screw 2 or the like, is detachably secured on a transverse shaft 25 pivotally mounted in the machin -frame. A step feeding mechanism actuated by the shaft ill of the knife arm l is adapted to effect a certain definite anticlockwise rotation of shaft 25 for advancing the table toward the knife. A suitable stop ring 25 serves to hold shaft 25 in position in its bearing.

On the shaft Ifl'is provided a coupling member 26 which only on the rotation of the shaft in one direction (when the arm is swung upward) actuates a shoulder on a second coupling member 2! turnable on the shaft. From coupling member 27 extends an arm 28 provided with a shoulder or pin 29 engaging a shoulder or a pin 30 on one arm 3! of a two-armed lever pivotally mounted on the transverse shaft 25. On arm 3! there is secured a spring 32 which tends to keep the members 29 and 3G in effective engagement with each other. The second arm 33 of the lever is provided with a widened head" tached at its one end to the frame 83 of the machine and at its other end to lever arm 33 and tends to move the lever arm upward. A similar ratchet'head 39 with roll it and track 41 for the roll is rigidly located in the frame; the ratchet allows the wheel to be turned in the direction of the arrow, but blocks it in the opposite direction. Several such ratchets may, of course, be provided, the said ratchets being actuated in the manner indicated below.

In the arm 33 and in a shoulder Q2 extending upward from the ratchet head 39 are pivotally mounted two-armed levers 13, M and d5, 46 respectively. The outer arms 34 and $5 each carry a tongue-like member extending from above and from below respective-1y into the respective ratchet track 36, il so as to rest against the rolls 3'! and All. The inner arms $3 and 45 are at their ends each provided with a shoulder or pin 41 and 48 respectively, which from above and from below respectively rest against the shaft 25 and the outer conical end of a sleeve 49 slidably mounted on the shaft. A spring 50 presses the arm 45 upward.

In the shaft 25, the largest part of which is hollow, is mounted a second shaft or rod 5| which is ope-rated from the outside by means of a handle 52 and which has a pin 53 projecting upward into an inclined groove 54 in the shaft 25. At its distal end the inner shaft 5| is also, by means of a pin 55 or the like engaging a groove, connected to and cooperating with the shaft 25, which pin also engages the sleeve 49 so that the sleeve is carried along by the movements of the respective shafts. For the pin there is in the outer shaft 25 made an oval hole 56 with the largest dimension in the axial direction, and the hole is further so arranged that the pin 55 receives as long a helical displacement as the pin 53 obtains at the turning of the shaft 5! relatively to the shaft 25.

Thus, if the shaft 5| is turned clockwise by means of the handle 52, the shaft receives, to begin with, a simultaneous peripherical and axial movement in the shaft 25 due to the groove and pin connection, whereby the sleeve 45 is displaced toward the wheel so that the pins 41 and 48 run up on the conical end of the sleeve.

Levers

43, 44, and 45, thus receive an oscillatory motion by which the rolls 3'! and 45 by the outer arms of the levers receive a displacement from the blocked position in the tracks to make it possible to turn the wheel clockwise. At a continued turning of the shaft 5! the said shaft can thus bring along the shaft 25 and thereby cause a backward motion of the table 5, if necessary. A spring 51 is located between the toothed wheel 24 and the sleeve 49, the said spring receiving a suitable strain by turning the wheel 24 to the necessary extent before the wheel is screwed on to the shaft. After releasing the handle 52 the spring 51 immediately returns the sleeve 49 and thus the shaft 5! to the position shown in Fig. 4, whereby the wheel 35 is blocked again against rotation clockwise. By means of the handle 52, however, rotation in the anticlockwise direction may freely take place, while the shaft 5! carries along the shaft 25 which is blocked.

In order to control the extent of the stepwise displacement and the length of the stroke respectively of the table 5 for the purpose of obtaining the desired thickness of the slices cut,

there is on the outside of the machine-frame provided a graduated, turnable adjustment scale 58 with a handle 59, which scale is connected with a shaft or rod pivotally mounted in the machine-frame. On rod there is secured a sector plate 6! or the like against which a shoulder 62 or the like on the lever-arm 33, at the upward swing of the latter, will rest. According to the position assumed by the plate 5| the lever may thus receive a greater or smaller swinging motion and so control the step movements of the table. Other arrangements for the same purpose are, of course, possible.

On the shaft 55 there is moreover turnably, but non-removably mounted a sleeve or body 63 provided with an upward directed pin 54 or the like cooperating with a pin or shoulder 65 on the underside of the table 5 for limiting the displacement of the table. A horizontal rod 86 having one end inserted under an elongated end portion 5? of the lever arm 43 is provided by means of which red the body 53 is held in its position.

As shown, the knife can be m ved to an intermediate position and fixed as by means of ratchet By insertion of a key or the like in the opening and slot at '19, 82, the knife shaft and knife can be rotated, as, for example, if it should be desired to perform a grinding operation.

The mode of operation is in just a few words as follows: After the meat to be sliced is placed on the table 5 and the latter has been advanced by the handle 52 to the position intended for cutting a slice, the operating arm 4 is swung down whereby the knife 2 is brought into rotation and cuts a slice. Upon returning the arm together with the then idle knife, the coupling member 26 on the shaft I B actuates the coupling member 27 just before the arm arrives at its uppermost position so that the arm 28 is swung upward carrying along the arm 3 I. The desired extent of the movement of the latter being controlled by means of the adjustment device 53 to SI. The arm 33 on the lever swings downward whereby the

roll ratchet

34, 35, 31 carries along the wheel 35 in the direction of the arrow (Figs. 6 and 7) and thus also the shaft 25 so that the table is advanced one step toward the knife path. At the downward swing of the operating arm again, the coupling member 26 releases the coupling member 2'! because the latter, on part of its circumference only is provided with shoulders cooperating with the former. The arm 28 falls down partly due to its own gravity, partly due to the action of the spring 38 on the lever arm 33, which latter, at its upward swing, does not carry along the wheel 35 when the roll ratchet is brought out of engagement with the wheel partly under the action of the lever arm 44.

During the repeated procedure the rotation of the wheel 35 and the shaft 25 clockwise cannot take place without special operation due to the braking action of the roll ratchet. If the table is to be returned the handle 52 is turned clockwise, whereby, as already mentioned, the shaft 5| connected with the handle first causes a displacement of the sleeve 49 so as to actuate the

lever arms

53 and 45 for the purpose of releasing the blocking engagement of the roll ratchets, after which the shaft carries along the shaft 25 and thus also the table 5.

The embodiment shown is. of course, only chosen as an example and modifications of the same are possible without departing from the scope of the invention.

Having now described my invention, what I claim as new and desire to secure by Letters Patent is:

1. In a slicing machine, a frame, a shaft journalled in the frame, an arm carried at one end of the shaft and adapted for reciprocal movement, a rotary knife journalled on the arm, a table in the frame movable perpendicularly to the path of the knife, a coupling connected to said shaft and adapted to be actuated as the knife is swung from slicing position and to be released as the arm is swung toward slicing position, a second shaft journalled in the frame and extending transversely of the first shaft, a guide member and a carrier for the table mounted for movement on said guide member, means upon the second and transversely arranged shaft engaging with a portion upon said table so that rotation of said second shaft will cause movement of said table on said guide member, a lever connected with the coupling member, and a lever mounted on the transverse shaft, connections between the levers and means adapted to be actuated by the lever on the shaft for turning the shaft in the direction for feeding the table toward the knife ath. p 2. In a slicing machine, a frame, a shaft journalled in'the frame, an arm carried at one end of the shaft and adapted for reciprocal movement, a rotary knife journalled on the arm, a table in the frame movable perpendicularly to the path of the knife and guide means for the table comprising guide rails for the table adapted to travel on guide bars, said guide bars being journalled in the frame, the end of each guide bar remoted from the knife path being flattened, and the length of the flattened portion of the bars corresponding to the length of said guide rails.

3. In a slicing machine, a frame, a shaft journalled in the frame, an arm carried by the shaft and adapted for reciprocal movement, a rotary knife journalled on the arm, a table movable in the frame perpendicularly to the path of the knife, a coupling connected to the shaft and adapted to be actuated as the arm is swung from slicing position and to be released as the arm is swung toward slicing position, a second shaft journalled in the frame and extending transverse 1y of the first-named shaft, guide means in said frame, a carrier for the table mounted on said guide means, means upon the second shaft engaging a portion upon the tabie so that rotation of said second shaft will cause movement of said table upon said guide means, a lever connected to the coupling member, a two-armed lever pivotally mounted on the second and transversely arranged shaft, one arm of said lever having a shoulder for engaging the lever connected to the coupling, a wheel fixed on the transverse shaft, and coupling devices on the second arm of the two-armed lever, said devices being adapted, as the lever on the transverse shaft is moved in one direction, to engage and rotate the wheel on the transverse shaft, and, as the lever is swung in the opposite direction, to cause the wheel to be blocked.

4. In a slicing machine, a frame, a shaft journalled in the frame, an arm carried by the shaft and adapted for reciprocal movement, a rotary knife journalled on the arm, a table movable in the frame perpendicularly to the path of the knife, a coupling connected to the shaft, adapted to be actuated as the arm is swung from slicing position and to be released as the arm is swung toward slicing position, a transverse shaft journalled in the frame, a carrier for the table, guide means in said frame supporting said carrier, means upon said transverse shaft engaging a portion upon said table so that rotation of the transverse shaft will cause movement of the table, alever connected to said coupling, a two-armed lever pivotally mounted on the transverse shaft, a shoulder on the latter lever for engaging the coupling lever, a wheel fixed on the transverse shaft, the second arm of the lever on the transe verse shaft carrying a ratchet head, a roll ratchet mounted in said head, and having a path forthe roll tapering upwardly, said ratchet roll being adapted to rotate said wheel in one direction and to block rotation in the opposite direction.

5. A slicing machine comprising a frame, a shaft journalled in the frame, an arm carried by the shaft and adapted for'reciprocal movements, a, rotary knife journalled on the arm, a table movable in the frame perpendicularly to the path of the knife, a coupling connected to the shaft and adapted to be actuated as the arm is swung from slicing position and to be released as the armis swung toward slicing position, a second shaft journalled in the frame and extending transversely of the first shaft, a guide and a carrier for the table mounted for m ovement upon said guide,

'means upon said transversely arranged second that rotation of said transverse shaft will cause movement of the table upon said'guide, a lever connected to the coupling member, a two-armed lever pivotally mounted on the transverse shaft, one'of the arms of the said lever having a shoulder for engaging the lever connected to the coupling, a wheel fixed on the transverse shaft, coupling devices carried by the second arm of the two-armed lever and adapted to engage and rotate the wheel as the lever is moved in one direction and to block rotation of the wheel as the lever is moved in the opposite direction, a rod pivotally mounted in the frame and extending parallel to said transverse shaft, a'graduated disc connected .to the rod and arranged outside the. said frame, means for adju t ng the disc, an arm fixed on the rod and extending into the path of the drive-means for said wheel, whereby the motion of two-armed lever and the feed of the table can be controlled.

6. In a slicing maehine, a frame, a shaft journalled in the frame, an arm carried by the shaft, a rotary knife journalled on the arm, a table movable in the frame perpendicularly to the path of the knife, a rack carried by said table, a coupling connected with the shaft and adapted to be actuated only as the knife arm is swung from slicing position, another shaft journalled in the frame and extending transversely of the first shaft, a toothed wheel journalled on the shaft meshing with the rack carried by the table, a lever connected with the coupling, a two-armed lever pivotally mounted on the transverse shaft, one arm of said lever engaging the coupling lever, a wheel fixed on the transverse shaft, a ratchet head carried by the other arm of the two-armed lever, said head being provided with a path tapering upwardly and a roller in said path, said roller ratchet being adapted to actuate the wheel and turn it in one direction, a spring in the ratchet head path for pressing the roller upwardly, a second ratchet head arranged at the opposite side of the periphery of the wheel and having a downwardly tapering path in which a roller is arranged, and means for actuating the rollers for releasing the wheel, whereby the transverse shaft can be turned to move the table from the path of the knife.

7. In a slicing machine, a frame, a shaft journalled in the frame, an arm carried by the shaft,

a rotary knife journalled on the arm, a table movable in the frame perpendicularly to the path of the knife, rack carried by said table, a coupling connected with the shaft and adapted to be actuated only as the knife is swung from slicing position, a-hollow shaft journalled in the frame and extending transversely of the first shaft, a toothed wheel on the shaft for engaging the rack carried by the table, a lever connected with the coupling, a two-armed lever pivotallymounted on the transverse shaft, one arm of said lever engaging the coupling lever, a wheel fixed on the transverse shaft, a ratchet head carried by the other arm of the two-armed lever, and having an upwardly tapering path in which a roller is carried, a spring in the said path for pressingthe roller upwardly, a second ratchet head arranged at the opposite side of the periphery of the wheel and having a downwardly tapering path in which a roller is mounted, said roller ratchets being adapted to engage and rotate the wheel in one direction and block rotation in the opposite direc tion, a rod in ,said hollow shaft, connections between the rod and shaft, means for imparting to the rod a simultaneous peripheral and axial movement in the hollow shaft, a sleeve slidable on the transverse shaft, means for connecting the sleeve to the transverse shaft and the inserted rod, and means actuated by the sleeve as it is displaced for actuating the rolls in the ratchets to release the wheel on the transverse shaft.

8. In a slicing machine, a frame, a shaft journalled in the frame, an arm carried by the shaft, a rotary knife journalled on the arm, a table movable in the frame perpendicularly to the path of the knife, a rack carried by said table, a coupling connected with the shaft and adapted to be actuated only as the knife is swung from slicing position, a hollow shaft journalled in the frame and extending transversely of the first shaft, a toothed wheel loosely mounted on the hollow shaft, and adapted to engage the rack carried by the table, a lever connected to the coupling, a two-armed lever pivotally mounted on the transverse shaft, one arm of said lever engaging the coupling lever, a wheel fixed on the transverse shaft, a ratchet head carried by the other arm of the two-armed lever, and having a path in which a roller is carried, a spring for pressing the roller upwardly, a second ratchet head carried at the opposite side of the periphery of the wheel, and having a path in which a roller is mounted, the roller ratchets being adapted to engage and rotate the Wheel in one direction and to block rotation in the opposite direction, a rod in said hollow shaft, connections between the rod and shaft, means for imparting to the rod a simultaneous peripheral and axial movement in the hollow shaft, a sleeve slidable on the transverse shaft, means for connecting the sleeve to the transverse shaft and to the inserted rod, means actuated by the sleeve as it is displaced for actuating the rolls in the ratchets to release the wheel on the transverse shaft, and a helical spring surrounding the hollow shaft and bearing against the said toothed wheel and the movable sleeve.

9. In a slicing machine, a frame, a shaft journalled in the frame, an arm carried by the shaft, a rotary knife journalled on the arm, a table movable in the frame perpendicularly to the path of the knife, a rack carried by said table, a coupling connected with the shaft and adapted to be actuated only as the knife is swung from slicing position, a hollow shaft journalled in the frame and extending transversely of the first shaft, a toothed wheel mounted on the hollow shaft and adapted to engage the rack carried by the table,

a lever connected 'to the coupling, a two-armed lever pivotally mounted on the transverse shaft, one arm of said lever engaging the coupling lever, a wheel fixed on the transverse shaft, a ratchet head carried by the other arm of the two-armed lever and having an upwardly tapering path in which a roller is carried, a second ratchet head arranged at the opposite side of the periphery of the wheel and having a downwardly tapering path in which a roller is located, said roller ratchets being adapted to engage and turn the wheel in one direction and to block rotation in the opposite direction, a rod in the hollow shaft, said hollow shaft being provided with a cam groove and an oval opening, and the inserted rod having pins cooperating with the groove and opening, and a sleeve slidable on the hollow shaft, the pin carried by the rod and passing through the oval opening in the shaft being adapted to connect the sleeve to the rod.

10. In a slicing machine, a frame, a shaft journalled in the frame, an arm carried by the shaft, a rotary knife journalled on the arm, a table movable in the frame perpendicularly to the path of the knife, a rack carried by said table,

a coupling connected with the shaft and adapted to be actuated only as the knife is swung from slicing position, a hollow shaft journalled in the frame and extending transversely of the first shaft, a toothed Wheel on the hollow shaft adapted to engage the rack carried by the table, a lever connected to the coupling and a two,- armed lever pivotally mounted on the transverse shaft, one arm of the latter lever engaging the coupling lever, a Wheel verse shaft, a ratchet head carried by the other arm of the two-armed lever, and having an up wardly tapering path in which a roller is arranged, a recond ratchet head arranged at the opposite side of the a downwardly tapering path in which a roller is located, said roller ratchets being arranged to engage and turn the wheel in one direction and to block its turning in the opposite direction and means for releasing the blocking devices, comprising a rod inserted in the hollow shaft, a sleeve slidable on the shaft, connections between the sleeve and rod, means for imparting simultaneous peripheral and axial movement to the rod, said sleeve being conical and levers, each having an arm carrying a projection extending into the path of the sleeve and the other arm of each lever having a tongue projecting into the path of one of said ratchet heads.

KARL ERIC OLSSON.

fixed on the transperiphery of the wheel having