US2094131A - Power reverse mechanism - Google Patents

Description

P 1937- L. o. MCLEAN 2,094,131

POWER REVERSE MECHANISM Filed June 15, 1936 3 Sheets-Sheet 1 INVENTOR. [4 4N0 0. M ZE/M/ ATTORNEYS Sept. 28, 1937. 1.. o. M LEAN POWER REVERSE MECHANISM Filed June 15, 1936 3 Sheets-Sheet 2 INVENTOR. c A 5/4 (a ATTORNEYS Patented Sept. 28, 1937 UNITED STATES PATENT OFFICE POWER REVERSE MECHANISM Application June 15,

8 Claims.

My invention relates to improvements in power-reverse mechanism of the type more particularly adapted for use in connection with power shovels, hoists, cableways, and the like, and

in which the power shaft rotates always in the same direction, such as is the case when a gasoline engine furnishes the driving power.

In power shovels used heretofore, and in which the source of power has been a gasoline engine or the like, it has been necessary to employ two drive shafts, rotating in opposite directions, in order to impart the crowding-in and crowding-out movements to the dipper, and also to impart rotary movement in either direction to the revolving frame or turntable supporting the cab, the engine and the driving and control mechanism. Furthermore, in these power shovels used heretofore, the brake drum has been set or released mechanically by a foot pedal during operation of the shovel, a hand brake being provided which the operator sets when leaving his post. This arrangement, as well as several other characteristics of these shovels, have been found to be unsafe for the reason that the brake drum and other control parts can be accidently released to permit the unit to operate out of control.

With the foregoing in mind, it is one of the objects of my invention to provide improved power-reverse mechanism of the character referred to which is in the form of a self-contained unit comprising a single drive shaft which rotates only in one direction, and by which, depending upon whether the mechanism is used in a power shovel, hoist, cableway or the like, can hold a drum, sprocket or gear stationary or cause these elements to rotate in either direction.

Another object of my invention is the provision of improved power-reverse mechanism of the character referred to in which the movable parts are held stationary or caused to rotate in either direction by the application of external, stationary brakes.

Another object of my invention is to provide improved power-reverse mechanism of the character referred to in which braking and movement in either direction of the driving elements are controlled conveniently and quickly by compressed air through valve mechanism so arranged that one of the brakes can be applied and the other released simultaneously without slip or less of control at any instant.

Another object of my invention is the provision of improved power-reverse mechanism of the character referred to in which provision is made for setting of the necessary brakes automatically 1936, Serial No. 85,256

uponrelease of the control lever or levers by the operator, whereby there is absolute safety against failure of the operator to set the brakes when leaving his post, or accidental release of a brake as is possible in the various mechanisms of this 5 type constructed heretofore.

Another object of my invention is to provide improved power-reverse mechanism of the character referred to in which provision is made for having the drive gearing run continuously in oil. 1

Other objects and advantages will hereinafter appear.

In accordance with my invention, a single drive shaft, which rotates in one direction only, drives a number of rotary flanges through planetary 15 gearing, the flanges being mounted for rotation about the axis of the shaft and controlled through the use of external brake bands, one of which is applied by spring pressure, the others being applied by air pressure.

Further in accordance with my invention, in power-reverse mechanism of the character referred to, the air-pressure connections to the control parts are made such that by actuation of a single valve a rotary driving element can be 25 released and simultaneously connected to the single drive shaft for rotation in one direction, by actuation of a second valve the driving element can be released without connecting it for rotation from the drive shaft, and by actuation of a third valve the driving element can be released and connected to the drive shaft for rotation in the reverse direction.

My invention resides in the improved construction of the character hereinafter described and 35 claimed.

For the purpose of illustrating my invention, an embodiment thereof is shown in the drawings, wherein,

Figure 1 is a simplified side elevational view of 40 a power-shovel in which two of my improved units are used for performing the three principal operations, namely, hoisting the dipper, crowding the dipper out and in, and rotating the turntable in different directions;

Fig. 2 is a plan view of Fig. 1;

Fig. 3 is an enlarged sectional view, taken on the line 33 in Fig. 2, of the power-reverse mechanism or unit which performs the functions of hoisting the dipper and crowding the dipper 50 out and in;

Fig. 4 is an enlarged fragmentary view taken from Fig. 2, showing diagrammatically the valve mechanism and the compressed air connections for controlling the mechanism;

Fig. 5 is a sectional view, the section being taken on the line 55 in Figs. 3 and 4;

Fig. 6 is a sectional view, the section being taken on the line 88 in Figs. 3 and 4;

li ig. 7 is an enlarged sectional view, taken on the line 1-1 in Fig. 2, of the power-reverse mechanism or unit which performs the function of rotating the turntable in different directions; and

Fig. 8 is an enlarged fragmentary view illustrative of my improved construction for an oil seal between the adjacent rotating parts or flanges.

With reference to Figs. 1 and 2, the reference numerals I 8 and I2 designate generally two of my improved power-reverse mechanisms or units mounted on a turntable I4 of a power shovel.

The unit I8 comprises a single drive shaft I8 carrying a cable drum I8 for raising and lowering the boom 28 and a sprocket drum 22 for crowding the dipper out and in through a sprocket chain 24 and the countershaft 28 and associated parts, as will be well understood.

The mechanism or unit I2 comprises a single drive shaft 28 which carries a hoist drum 88 and a pair of bevel gears 32 and 84. These gears are in mesh with a bevel gear 38 to rotate the associated pinion 88 in either direction to impart the same movement to the turntable provided on its underside with the circular rack 48 with which the pinion 88 is in mesh.

In operation of the shovel, the two drive shafts I8 and 28 are rotated continuously and always in the same direction under power from a gasoline engine 42 which is connected to the shaft 28 through a transmission unit 44 of conventionalconstruction and gears 48 and 48. The shaft I8 is driven from the shaft 28 by a sprocket chain 58.

The details of construction of the unit I8 will now be described, with reference particularly to Figs. 3, 5 and 6. A first flange 52, a second flange 54 and a third flange 58 are mounted on the shaft I8 for rotation with respect thereto. These flanges are provided, respectively, with brake bands 58, 88 and 82 which are either released to permit free rotation of the flanges or are applied to retard or prevent any rotation thereof. For the purpose of rotating the flange 54 from the drive shaft I8 in one direction to impart crowding-in movement to the dipper, planetary gearing is disposed as shown within the flange 54 and comprises a sun gear 84 fixed on the shaft I8, planet gears 88, and an internal gear 88 which is integral or fixed with respect to the flange 54. The planet gears 88 rotate on stub shafts 18 fixed in the flange 52. With the brakes 58 and 82 released and the brake 88 set, the drum 22 which is integral with the flange 54, will be held against rotation. With the brake 58 applied and the brakes 88 and 82 released, the drum 22 will be rotated in one direction from the shaft I8 through the connection provided by the planetary gearing, to impart crowding-in movement to the dipper.

Reverse rotation of the drum 22 is brought about through planetary gearing disposed within the flange 58 and which comprises a sun gear 12 fixed on the shaft I8, planet gears 14, and an internal gear 18 integral or fixed with respect to the flange 58. The planet gears I4 are rotatable on stub shafts l8 fixed in the side flange 88 of the drum 22.

With the brakes 58 and 88 released and the brake 82 applied, the drum 22 will be caused to rotate in the reverse direction on account of the planetary gearing, to impart crowding-out movement to the dipper, as will be well understood.

The brake 82 is applied upon admission oi compressed air into a cylinder 82 to cause pivotal movement of a lever 84 in a counter-clockwise direction about the pivotal connection 88, the parts being arranged and disposed as shown to cause this action to tighten the brake band about the flange 58.

A spring 88 back of the piston in the cylinder 82 assists in releasing the brake 82 when the air pressure in the cylinder is relieved. The brake 58 associated with the flange 52 is applied in the same mannerby admission of compressed air into a cylinder 88, the construction and arrangement being the same as shown in Fig. 5.

The brake 88 associated with the flange 54 is applied by a relatively stiff spring 82 compressed back of a piston 84 in a cylinder 88 to urge the brake lever 88 in a clockwise direction about its pivotal support I88. To release the brake 88, compressed air is admitted into the cylinder 88 by way of a connection I82, whereupon the piston 84 is forced to the right to cause pivotal movement of the lever 88 in the counter-clockwise direction.

From the foregoing it will be seen that the two brakes 58 and 52 are air-set and that the brake 88 is spring-set.

Compressed air is admitted to the cylinder 88 through a connection I84 by opening a first control valve I88, and the compressed air is exhausted from this cylinder by moving this valve to the position shown. A second control valve I88 admits compressed air into the cylinder 88 when opened, and exhausts the air from this cylinder when it is moved to the position shown. In this case, the compressed air feeds through a connection I I8, a shuttle valve I I2, a connection H4, a shuttle valve H8, and the connection I82. When a third control valve H8 is opened, compressed air is admitted into the cylinder 82 through a connection I28, and is exhausted from this cylinder when valve H8 is moved to the position shown.

The shuttle valves H2 and H8 are of conventional construction, and operate, when only the second control valve I88 is opened, to pass compressed air to the cylinder 88, and to cut 01! or prevent compressed air from passing to the cylinders 82 and 88. By manipulation of the single valve I88, therefore, the brake 88 can be released and applied as desired, without causing application of the brakes 58 and 82.

With the control valves in the positions shown, if only the first valve I88 is opened, compressed air is admitted into the cylinder 88 to apply the brake 58, and is also admitted through the shuttle valve I I8 and the connection I82 into the cylinder 88 to release the brake 88. In this case, the shuttle valve H8 is eifective to cut oil. the compressed air to the cylinder 82. It will therefore be seen that by manipulation of the single valve I88, the brake 58 can be applied and the brake 88 is released simultaneously, or the brake 58 can be released and the brake 88 applied simultaneously, the brake 82 remaining released during these movements.

With the control valves in the positions shown,

' upon opening the third valve H8, compressed air this time cutting off compressed air to the cylinder 80. By manipulation of the third control valve II8, therefore, the brake 62 can be applied and the brake 60 released simultaneously, or the brake 62 can be released and the brake 60 applied simultaneously, the brake 58 remaining released during these movements.

From the foregoing it will be seen that when either of the brakes 58 and 62 is set, the brake 60 is released simultaneously and by manipulation of the same valve, and that when either of the brakes 68 and 62 is released, the brake 60 is simultaneously applied by manipulation of the same valve.

For the purpose of actuating the three control valves by manipulation of a single hand lever, it is proposed to provide a construction of the gen eral type disclosed in my Patent No. 1,711,896, issued May 7, 1929.

Mounted loosely on the drive shaft I6 is a bevel gear I 22 which meshes with a complementary gear I24 connected to drive the wheels of the truck I24 on which the entire mechanismmmd apparatus is mounted. Upon movement of a conventional clutch I26 to the left, the gear I22 is connected to the shaft I6 for rotation therewith. Movement to the right of this clutch connects the drum l8 for rotation with the shaft I 6. A planetary gear unit and brake, similar to those described above, and which is designated generally by the reference numeral I28, is associated with the hoist drum I8 to hold it stationary or cause it to be rotated from the drive shaft I6 to raise the bucket. The bucket drops by gravity when the brake is released. The brake associated with the unit I28 is spring-set.

Also fixed on the shaft I6 is a brake drum I30 about which is a brake band I32. The band I32 is normally released, and is set by hand to hold the drive shaft I6 against rotation, if required.

The power-reverse mechanism or unit I2 is similar in construction and manner of operation to the unit I0, and in Figs. 2 and 7 the various parts are designated by the same reference numerals as the corresponding and respective parts comprising the unit I0, except that the sufllx a is used. Mounted loosely on the drive shaft 28 is a first flange 52, a second flange 54a and a third flange 56a with which are associated, respectively, the brake bands 58a, 60a and 62a. The bevel gear 32, which is loose on the shaft 28, is provided with a flange 80a corresponding to the flange 80 in Fig. 3.

Planetary gearing is associated with the first flange 52a and the second flange 54a. for imparting rotary movement to the bevel gear 34 when the brake 58a is applied and the brake 60a simultaneously released, thereby causing the turntable to rotate in one direction. This planetary gearing comprises a sun gear 64a, planet gears 66a, and an internal gear 68a integral or fixed with respect to the flange 52a. The planet gears 66a are rotatably mounted on stub shafts 10a flxed in the flange 54a.

Planetary gearing is also associated with the flanges 56 and 80a, and comprises a sun gear 12a fixed on the drive shaft 28, planet gears 14a, and an internal gear 16a integral or fixed with respect to the flange 56a. The planet gears 14a are rotatably mounted on stub shafts 18a flxed in the flange 80a. Upon application of the brake 62a, the bevel gear 32 is caused to rotate from the shaft 28 in the same direction in which the bevel gear 34 is caused to rotate when the brake 58a is applied. However, on account of the fact that the bevel gears 32 and 34 are on diametrically opposite sides of the complementary bevel gear 86,

rotation of the gear 32 causes the turntable torotate in the opposite direction. The brake 60a is spring-set by a coil spring compressed in a cylinder 06a, and the brakes 58a and 62a are applied by admission of compressed air into the cylinders 90a and 82a, respectively.

The control valves and the compressed air connections for the unit I2 have not been shown, as these are identical to those for the unit I0. That is, when the flrst valve, corresponding to the first valve I06 in Fig. 4, is opened, the brake 58a is applied and the brake 60a simultaneously released. When this valve is returned to its original position, the brake 58a is released and the brake 60a simultaneously applied. When the second control valve, corresponding to the second valve I08 in Fig. 4, is opened, the brake 60a is released, and when this valve is returned to its original position the brake 60a is spring-set, the brakes 58a; and 62a during these movements remaining released. A third control valve, corresponding to the third valve II 8 in Fig. 4, is opened to set the brake 62a and simultaneously release the brake 60a, and is returned to its original position to release the brake 62a and simultaneously apply the brake 60a.

A brake band I34, which is spring-set, is provided for hold ng and releasing the drum 30. This drum is caused to rotate from the shaft 28 upon application of a brake band I36 through planetary gearing associated with the flanges I38 and I40 and which is constructed and operates in the same manner as the planetary gearing described above.

It is proposed to bias all control valves to the positions shown in Fig. 4, so that when the operator releases his hold on the hand levers controlling the units I and I2, the various parts are automatically restored to the 011? positions so that the brakes 58, 62, 58a and 62a are released, and the brakes 60, the brake associated with the unit I 28, and the brakes 60a and I34 are applied. On account of this action, it is not required of the operator that he set any brakes or otherwise make conditions safe when he leaves his post and which might accidentally be released to cause the apparatus to operate out of control.

An important advantage of my improved power-reverse mechanism resides in the fact that spur gears are used for causing the various movements of the dipper and the turntable, and that the sun and planet and internal gears of the planetary. gearing have substantially the same respective pitch diameters, and that the flanges in each case are retarded or held against rotation by external, stationary brakes which are interchangeable. It will be seen, also, that on account of the difference between the relation of the gears associated with the flanges 52 and 54 and the relation of the gears associated with the flanges 88 and 56, the out-crowd movement of the dipper caused upon application of ,the brake 62 is relatively slow and powerful, whereas the in-crowd movement of the dipper caused by the application of the brake 58 is relatively fast and less powerful. In the unit I2, however, the relation of the gears between the flanges 52a and 54a is the same as that between the flanges 80a and 56a. The rate of swing in both directions, upon application of the brakes 58a and 62a, is therefore the same.

use a construction as shown in Fig. 8. For the flanges 52a and 54a, this comprises an annular ring I42 fixed to the flange 52a by bolts I to provide an annular wall or flange 6 extending about the edge of the flange Mo on the open side thereof and directed radially inwardly toward the axis of rotation. The flange 6 provides an oil well, and is provided with annular ribs H8 concentric about the axis of rotation and which are received and have a running flt in annular grooves I50 in the face of the adjacent flange 54a. The clearance between the ribs 8 and the flange 54a is of the order of flve-thousandths of an inch. Oil is placed in the flange 52a to be at a depth of about one-half the diameter of the planet gears when the flange 52a is stationary, and when this flange rotates to cause the oil to spread out under centrifugal force, to be at a depth less than the height of the flange H6. The close fit of the ribs I48 with respect to the adjacent flange 54a prevents the oil from seeping out between the two flanges when the flange flais stationary, but does not interfere with the relative rotary movement of these flanges. Oil seals of similar construction are provided between the flanges 52 and 54, the flanges and 56, the flanges 80a and 56a, and the flanges I38 and I".

While I have shown and described my improved power-reverse mechanism embodied in a power shovel, it will be understood that this is only for the purpose of showing one use of the mechanism, and that the same is Just as adaptable for use in connection with hoists, cableways and the like. Furthermore, it will be understood that various modifications, such as in the size, shape and arrangement of the parts might be made without departing from the spirit of my invention or the scope of the claims.

I claim as my invention:

1. In power-reverse mechanism comprising a drive shaft and characterized by the fact that during normal operation thereof said shaft rotates only in one direction, a first flange and a second flange and a third flange each rotatable with respect to said shaft and about the axis thereof, normally released means associated with the first flange for retarding rotation thereof when applied, fluid-pressure means for applying said retarding means, means associated with the second flange for retarding rotation thereof, spring means for normally applying said secondnamed retarding means, fluid-pressure means for releasing said spring means, normally released means associated with the third flange for retarding rotation thereof, fluid-pressure means for applying said third-named retarding means, planetary gearing associated with the first and second flanges for imparting rotary movement to the second flange when rotation of the first flange is retarded on operation of said first mentioned fluid pressure means and comprising a sun gear fixed for rotation with said shaft, and planetary gearing associated with the third flange and comprising a sun gear fixed for rotation with said shaft.

2. In power-reverse mechanism comprising a drive shaft and characterized by the fact that during normal operation thereof said shaft rotates only in one direction, a first flange and a second flange and a third flange each rotatable with respect to said shaft and about the axis thereof, means associated with the first flange for retarding rotation thereof, fluid-pressure means including a flrst control valve for applying said retarding means, means associated with the second flange for retarding rotation thereof, spring means for applying said second-named retarding means, fluid-pressure means including a second control valve for releasing said spring means, means associated with the third flange for retarding rotation thereof, fluid-pressure means including a third control valve for applying said third-named retarding means, planetary gearing associated with the first and second flanges for imparting rotary movement to the second flange when rotation of the first flange is retarded and comprising a sun gear fixed for rotation with said shaft, planetary gearing associated with the third flange and comprising a sun gear fixed for rotation with said shaft, and valve means for cutting off the fluid pressure to both the first-named and third-named fluid-pressure means when the second control valve is opened and operable to apply the fluid-pressure to the second-named fluid-pressure means when either of the first and third control valves are opened.

3. In power-reverse mechanism comprising a drive shaft and characterized by the fact that during normal operation thereof said shaft rotates only in one direction, a first flange and a second flange and a third flange each rotatable with respect to said shaft and about the axis thereof,'the second flange being disposed between the other two flanges, means associated respectively with said flanges for retarding rotation thereof selectively, a fourth flange rotatable with respect to said shaft about the axis thereof and disposed between the second and third flanges, planetary gearing associated with the first and second flanges for imparting rotary movement to the second flange when rotation of the first flange is retarded and comprising a sun gear fixed for rotation with said shaft and an internal gear fixed with respect to the first flange and planet gears rotatable about axes fixed with respect to the second flange, and planetary gearing associated with the third flange and comprising a sun gear fixed for rotation with said shaft and an internal gear fixed with respect to the third flange and planet gears rotatable about axes fixed with respect to the fourth flange.

4. In power-reverse mechanism comprising a drive shaft and characterized by the fact that during normal operation thereof said shaft rotates only in one direction, a flrst flange and a second flange and a third flange each rotatable with respect to said shaft and about the axis thereof, means associated with the first flange for retarding rotation thereof, spring means for normally releasing said retarding means, manually controlled fluid pressure means for applying said retarding means, means associated with the second flange for retarding rotation thereof, spring means for normally applying said second-named retarding means, fluid pressure means for releasing said spring means, means associated with the third flange for retarding rotation thereof, spring means for normally releasing said third-named retarding means, manually controlled fluid pressure means for applying said third-named retarding means, planetary gearing associated with the first and second flanges for imparting rotary movement to the second flange when rotation of the first flange is retarded, and planetary gearing associated with the second and third flanges so that rotary movement in an opposite direction is imparted to the second flange when rotation of the third flange is retarded.

5. In power-reverse mechanism comprising a drive shaft and characterized by the fact that shaft, individual braking means normally re-' leased for the first and third flanges, braking means normally applied for the second flange, a

system of planetary gearing associated with said flanges and the drive shaft which will impart rotary movement to the second flange upon braking of the first flange and rotary movement in an opposite direction to the second flange upon braking of the third flange, and manually controlled valves for said braking means so arranged that an application of the braking means to the first or third flanges will automatically release the braking means on the second flange and impart the desired rotary movement to said second flange.

6. In power-reverse mechanism comprising a drive shaft and characterized by the fact that during normal operation thereof said shaft rotates only in one direction, first, second and third flanges, each being freely rotatable on said drive shaft, individual braking means normally released for the first and third flanges, braking means normally applied for the second flange, individual fluid pressure cylinders for operating each braking means, a system of planetary gear ing associated with said flanges and the drive shaft which will impart rotary movement to the second flange upon braking of the first flange and rotary movement in an opposite direction to the second flange upon braking of the third flange, and manually controlled valves for the supply and release of fluid under pressure to said cylinders so arranged that an application of the braking means to the first or third flanges will automatically release the braking means on the second flange and impart the desired rotary movement to said second flange.

7. In power reverse mechanism comprising a driveshaft and characterized by the fact that during normal operation thereof said shaft rotates only in one direction, first, second and third 45 flanges, each being freely rotatable on said drive shaft, individual braking means normally released for the first and third flanges, braking means normally applied for the second flange, a system of planetary gearing associated with said flanges and the drive shaft which will impart rotary movement to the second flange upon braking of the first flange and rotary movement in an opposite direction to the second flange upon braking of the third flange, a manually controlled valve for each individual braking means, and automatic valves which are responsive to the operation of the manually controlled valves in the braking of the first or third flanges to automatically efiect release of the braking on the second flange and permit the planetary gearing to impart the desired rotary movement to said second flange.

8. In power-reverse mechanism comprising a drive shaft and characterized by the fact that during normal operation thereof said shaft rotates only in one direction, a first flange and a second flange and a third flange each rotatable with respect to said shaft and about the axis thereof, the second flange being disposed between the other two flanges, means associated respectively with said flanges for retarding rotation thereof selectively, a fourth flange rotatable with respect to said shaft about the axis thereof and disposed between the second and third flanges, oppositely disposed bevel gears associated with the second and fourth flanges, planetary gearing associated with the first and second flanges for imparting rotary movement to the second flange when rotation of the first flange is retarded and comprising a sun gear fixed for rotation with said shaft and an internal gear fixed with respect to the first flange and planet gears rotatable about axes fixed with respect to the second flange, and planetary gearing associated with the third flange and comprising a sun gear fixed for rotation with said shaft and an internal gearfixed with respect to the third flange and planet gears rotatable about axes fixed with respect to the fourth flange.

.LELAND O. MoLEAN.

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