US2937788A

US2937788A - Fluid operated escapement device

Info

Publication number: US2937788A
Application number: US726264A
Authority: US
Inventors: Darsie Burns
Original assignee: Dixon Automatic Tool Inc
Current assignee: Dixon Automatic Tool Inc
Priority date: 1958-04-03
Filing date: 1958-04-03
Publication date: 1960-05-24
Anticipated expiration: 1977-05-24

Description

May 24, 1960 B. DARSIE FLUID OPERATED EISCAPEMENT DEVICE Filed April 3, 1958 v-JLe.

My W

United States PatentO FLUID OPERATED ESCAPEMENT DEVICE BurnsDarsie, Rockford, Ill., assignor to Dixon Automane Tool, Inc., Rockford, 111., a corporation of Illinois Filed Apr. 3, 1958, Ser. No. 726,264 6 Claims. (Cl. 221-298) The present invention relates generally to article controlling escapement mechanisms and more particularly to an escapement mechanism for delivering small articles one by one from a storage magazine.

It is the primary aim of the invention to provide a novel fluid operated escapement release mechanism that is positive acting and reliable while being exceptionally economical to manufacture.

With more particularity it is an object to provide a fluid pressure operated escapement mechanism that does not rely upon a valve arrangement for proper sequential operation and therefore avoids critical machining and adjusting problems. In greater detail, it is an object to provide an escapement mechanism as characterized above, comprising a pair of units inwhich the retaining and releasing operations occur in an accurately timed and consistent sequence so as to insure the feeding of articles one by one. In one of the aspects of the invention means are provided for causing the units to act diiferentially to insure timing overlap, and thus positive gating, even though the units are supplied with fluid simultaneously and from the same fluid source. It is nevertheless an object to provide an article release unit and a stack retaining unit, with each of the units having a large number of common parts so as to minimize manufacturing costs.

It is also an object to provide an escapement mechanism of the above type that is readily adaptable to a wide variety of operating situations in that its component units can be individually positioned and mounted so as to control articles of widely varying sizes. It is a related object to provide an escapement mechanism having the above characteristics which is also extremely simple to adjust for handling articles of various sizes and shapes since its two component units are merely coupled to a common air pressure source and no critical timing adjustment is needed.

Other objects and advantages of the invention will be-v come apparent upon reading the attached detailed description and upon reference to the drawings in which:

Figure 1 is an elevation view of an escapement mechanism embodying the present invention; V

Fig. 2 is a stop motion fragmentary'view similar to Figure 1 showing the escapement mechanism in an intermediate position of its operating cycle;

Fig. 3 is a fragmentary stop motion view similar to Fig. 2 showing the parts of the escapement mechanism in their operative positions;

Fig. 4 is a section taken along line 4-4 of Fig. 1;

Fig. 5 is a section taken along the line 5-5 of Fig. 1; and a Fig. 6 is an elevation view similar to Fig. 1 showing a modified installation of the escapement mechanism embodying the present invention.

While the invention will be described in connection with a preferred embodiment, it will be understood that I do not intend to limit the invention to that em bodiment. I On the contrary, I intend to cover all alternatives, modifications and equivalents as may be ineluded within the spirit and scope of the invention as defined by the appended claims;

Turning now to Figure 1, there is shown an escapement mechanism 10, embodying the present invention, arranged to deliver, one by one, a series of articles A. In the illustrated embodiment, the articles A are alined in a magazine 11 which defines a downwardly inclined pathway12. The articles A are prevented from sliding down the pathway 12 by their engagement with an article release plunger 15 that extends into the pathway 12.

Single articles are released from the magazine 11' by moving the article release plunger 15 from the pathway 12 after a stack retaining plunger 16 has been urged into the pathway to arrest movementof the stack of articles behind the first or lowermost article in the stack. The

sequential operation of the

plungers

15, 16 is illustrated I Figs. 1, 2 and 3. In Fig. l'theplungers are shown in their normal rest positions with the articles A held in the magazine 11 by the plunger 15. In Fig. 2, the stack retaining plunger 16 has been urged downwardly into engagement with the second article of the stack while the plunger-15 remains extended into the pathway 12. In

Fig. 3, the stack releasing plunger 15 has been withdrawn from the pathway 12 so as to release the lowermost articleA while the stack retaining plunger 16-remains effective to hold the remaining articles in position. The plunger operating sequence is, of course, reversed when the plungers are returned to their normal rest positions. That is, the plunger 15 is lowered until itagain extends into the pathway 12 before the plunger 16 is raised from the pathway to its normal position.

In accordance with the present invention, the

plungers

15, 16 are resiliently urged into their normal rest positions and are operated by a pair of fluid pressure motors coupled to a common source of fluid pressure; the eflece tive, piston areas of the motors and the resilient forces on the plungers being so related as to urgegtheplunger ,16 into the pathway 12'before the plunger 15 is moved from the pathway upon the introduction of fluid pressure. In

this way, the articles A may be released from the magazine 11 one by one in the manner described above.

In the preferred embodiment, the

plungers

15, 16 have formed integrally therewith pistons 17 and 18, respectively. The piston 17. is slidably fitted in a cylinder 19 normal rest positions, a spring 25 is compressed inthe cylinder 19 and arranged to bear againstth e piston 17,

and a spring 26 is compressed in the cylinder 20 and arranged to bear against the piston 18. The spring 25 is seated about a pin 27 formed integrally at the top of the piston 17, and the spring 26 is seated by being fitted about a collar 30 formed on the piston 16.

In order to supply fluid pressure and operate the

plungers

15, 16, a connector 31 is provided for introducing fluid under pressure into the cylinder 19 on the side of the piston 17 opposite the spring 25, and a connector 32 is provided for introducing fluid into the cylinder20 on the side of the piston 18 opposite the spring 26. The

connectors

31, 32 are coupled to a common source of fluid pressure by a conduit assembly 33, and avalve 34 is provided in the assembly for controlling the flow of fluid pressure to the cylinders 19, 20.

Preferably, proper sequential operation of the

plungers

15, 16 is assured by two distinct factors. First, it will be seen that the effective piston area against which the fluid pressure may act in moving the plunger is significantly less than the eflective piston area against which the fluid pressure acts in moving the plunger 16.. In cylinder 20, the fluid pressure acts against a piston area substantially equal to the cross-sectional area of the cylinder. In cylinder 19,because of the interconnection of the plunger 15 with the piston 17, the eflective piston area is substantially reduced. It will therefore be seen that, other factors being equal, as fluid pressure is uniformly developed in each of the cylinders 19 and 20, the higher force on piston 18 will move the plunger 16 toward the pathway 12 before the plunger 15 is operated.

The second factor for securing sequential operation of the two

plungers

15, 16 is the fact that spring 25 is selected so as to exert a stronger force holding the plunger 15 in its normal position than is exerted by the spring 26 holding the plunger 16 in its normal position. It will be understood therefore, that as the fluid pressure tending to move these plungers is gradually. increased, the plunger 16 will be moved before the plunger 15 because of the lighter spring force which must be overcome.

In summary then, operation of the valve 34 will admit fluid under pressure into each of the cylinders 19, through the

respective connectors

31, 32. The greater effective piston area of piston 18, and the lighter spring 26, will cause operation of the plunger 16 to its Fig. 2 position before the plunger 15 is moved. Thus, sequential operation is obtained without valving fluid pressure first to one and then the other of the cylinders.

It is a feature of the invention that the

plungers

15, 16 and their related operating structure are substantial duplicates of one another. It will be noted, for example, that the plunger-piston assembly 15, 17 is identical to the plunger-piston assembly 16, 18. The piston 18 is provided with a pin 28 on its upper surface corresponding to the pin 27 on the piston 17. Preferably, the pin 28 abuts the cap 24 and establishes the normal rest position of the plunger 16. It will also be observed that the plunger 15 is formed with a collar 29 which corresponds to the collar 30 on the plunger 16. In the illustrated embodiment, the collar 29 abuts the bottom wall of the cylinder 19 and thus establishes the normal rest position of the plunger 15.

Each of the pistons 17, 18 is formed with a central peripheral groove in which O-rings 37, 38, respectively, are fitted for establishing a fluid pressure seal between the respective pistons and their surrounding cylinders.

Not only are the plunger assemblies identical, but it will be noted that the

cylinder blocks

21, 22 are also substantially identical. The fluid pressure connector 31 communicates with the cylinder 19 through a passage 39, and a corresponding passage 40 is provided in the block 22 to serve as a discharge port for relieving back air pressure on the bottom of the piston 18. Similarly, the fluid pressure connector 32 communicates with the cylinder 20 through a port 42 corresponding to a port 41 formed in the cylinder block 21 which serves to relieve the air pressure behind the piston 17 when it is operated.

By making the various component parts of the mechanism 10 interchangeable, it will be appreciated that substantial savings in manufacturing and servicing costs are effected.

For the purpose of mounting the cylinder blocks 21, 22 and the

plungers

15, 16 carried thereby, the blocks are provided with identically located sets of tapped

holes

43, 44 and 44a, respectively. In the embodiment illustrated in Figs. 1 to 5, the blocks are mounted on L'-shaped brackets 45 which are secured to the sides of the magazine 11 and fastened to the

respective cylinder blocks

21, 22 by screws 46 threaded into the tapped holes 44a.

It is a further feature of the invention that the cylinder blocks 21, 22 are completely independent and-distinct with the only connection between the fluid motors operating the article release piston 15 and the stack retaining piston 16 being the conduit assembly 33 which supplies fluid pressure from a common source to each of the units. The escapement mechanism 10 is, therefore, very flexible and can be readily adapted to handle a wide variety of situations. For example, in Fig. 6, the

blocks

21, 22 are shown mounted on a strip 50 at right angles to one another so that the article engaging ends of the

plungers

15 and 16 are brought into very close proximity to one another. In this embodiment, the blocks are fastened to the strip by screws (not shown) threaded into the tapped

holes

43 and 44. This enables the mechanism 10 to handle very small articles B.

In the preferred and illustrated arrangement for handling small articles, the close proximity of the

plungers

15, 16 is greatly enhanced by providing the latter with pointed tips 15a, 16a, respectively. The operation of the plungers remains as described above.

I claim as my invention:

1. In a fluid operated escapement mechanism having a pathway down which articles are propelled, the combination comprising, a pair of mutually independent cylinder blocks spaced along said pathway, the lowermost of said blocks defining an article release cylinder and the other block defining a stack retaining cylinder, said cylinders having bores of equal diameter, a pair of pistons each being slidably mounted in a respective one of said cylinders and each piston having a plunger extending from one end thereof, said plungers slidably fitting through one end of their respective cylinder blocks so as to be movable into and out of said pathway, a first spring compressed in said article release cylinder on the side of the associated piston opposite the plunger so as to urge the plunger from the cylinder into said pathway, a second spring compressed in said stack retaining cylinder and surrounding the associated plunger so as to bear against the piston and urge the plunger into the cylinder and out of said pathway, and means for introducing fluid under pressure from a common source to said cylinders on the sides of the respective pistons opposite their respective springs whereby upon the introduction of fluid through said means, the greater effective piston area in the stack retaining cylinder resulting from the piston-cylinder connection in the article release cylinder and correlation of the strength of the springs automatically causes the plunger in the former cylinder to operate before operation of the plunger in the latter cylinder.

2. In a fluid operated escapement mechanism having a pathway down which articles are propelled, the combination comprising, a pair of mutually independent cylinder blocksspaced along said pathway, the lowermost of said blocks defining an article release cylinder and the other block defining a stack retaining cylinder, said cylinders having bores of equal diameter, a pair of pistons each being slidably mounted in a respective one of said cylinders and each piston having a plunger extending from one end thereof, said plungers slidably fitting through one end of their respective cylinder blocks so as to be movable into and out of said pathway, a first spring compressed in said article release cylinder on the side of the associated piston opposite the plunger so as to urge the plunger from the cylinder into said pathway, a second spring compressed in said stack retaining cylinder and surrounding the associated plunger so as to bear against the piston and urge the plunger into the cylinder and out of said pathway, said first spring being effective to exert a stronger force on its piston than the force exerted by said second spring on its piston, and means for introducing fluid under pressure from a common source to said cylinders on the sides of the respective pistons opposite their respective springs whereby upon the introduction of fluid through said means, the greater effective piston area in the stack retaining cylinder resultmg from the piston-cylinder connection in the article automatically causes the plunger in the former cylinder to operate before operation of the plunger in the latter cylinder.

3. In a fluid pressure operated escapement mechanism having a pathway for the movement of articles, the combination comprising, an article release cylinder and a stack retaining cylinder positioned along said pathway, a pair of pistons having plungers coupled thereto and being slidably mounted in respective ones of said cylinders so as to move said plungers into and out of said pathway, a pair of springs associated respectively with each of said cylinders with the article release cylinder spring urging the associated plunger toward an article blocking position in said pathway and the stack retaining cylinder spring urging the associated piston to an article clearing position out of said pathway, and means for introducing fluid under pressure from a common source to each of said cylinders so that the fluid pressure acts in opposition to the force of said springs, the eflective piston area in the article release cylinder being less than the elfective piston area in the stack retaining cylinder and said article release cylinder spring being stronger than said stack retaining cylinder spring so that upon introduction of fluid pressure the stack retaining cylinder plunger is urged into said pathway before the article release cylinder plunger is moved from said pathway.

4. In a fluid pressure operated escapement mechanism having a pathway for the movement of articles, the combination comprising, an article release cylinder and a stack retaining cylinder positioned along said pathway, a pair of pistons having plungers coupled thereto and being slidably mounted in respective ones of said cylinders so as to move said plungers into and out of said pathway, a pair of springs associated respectively with each of said cylinders with the article release cylinder spring urging the associated plunger toward an article blocking position in said pathway and the stack retaining cylinder spring urging the associated piston to an article clearing position out of said pathway, and means for introducing fluid under pressure from a common source to each of said cylinders so that the fluid pressure acts in opposition to the force of said springs, said article release cylinder spring being stronger than said stack retaining cylinder spring so that upon introduction of fluid pressure the stack retaining cylinder plunger is urged into said pathway before the article release cylinder plunger is moved from said pathway.

5. In a fluid pressure operated escapement mechanism having a pathway for the movement of articles, the combination comprising, an article release cylinder and a stack retaining cylinder positioned along said pathway, a pair of pistons having plungers coupled thereto and being slidably mounted in respective ones of said cylinders so as to move said plungers into and out of said pathway,

a pair of springs associated respectively with each of said cylinders with the article release cylinder spring urging the associated plunger toward an article blocking position in said pathway and the stack retaining cylinder spring urging the associated piston to an article clearing position out of said pathway, and means for introducing fluid under pressure from a common source to each of said cylinders so that the fluid pressure acts in opposition to the force of said springs, the effective piston area in the article release cylinder being less than the effective piston area in the stack retaining cylinder and the strength of the springs being correlated so that upon introduction of fluid pressure the stack retaining cylinder plunger is urged into said pathway before the article release cylinder plunger is moved from said pathway.

6. In a fluid pressure operated escapement mechanism having a pathway for the movement of articles, the combination of, an article release cylinder and a stack retaining cylinder positioned along said pathway, a pair of pistons having plungers coupled thereto and being slidably mounted in respective ones of said cylinders so as to move said plungers into and out of said pathway,

a pair of springs associated respectively with each of said cylinders with the article release cylinder spring urging the associated plunger toward an article blocking position in said pathway and the stack retaining cylinder spring urging the associated piston to an article clearing position out of said pathway, and means for introducing fluid under pressure from a common source to each of said cylinders so that the fluid pressure acts in opposition to the force of said springs, the effective piston area of each piston and the strength of the springs acting against each piston being correlated so that upon introduction of fluid pressure the stack retaining cylinder plunger is I urged into said pathway before the article release cylinder plunger is moved from said pathway.

References Cited in the file of this patent UNITED STATES PATENTS 2,611,911 Graham et al. Sept. 30, 1952