US2128157A - Pneumatic tool - Google Patents

Description

J. A. MONNIER ET AL PNEUMATIC TOOL Filed Jan. 28, 1937 INVENTOR. l2 Iva/Irma? 00w 6. .BRms r ATTORNEY Aug. 23, 1938.

p f F Q ha x QF Eu w able gaseous fluid under pressure.

Patented Aug. 23, 1938 PATENT, OFFICE PNEUMATIC TOOL James A. Monnier and Corning S. Brush, Algonac, Mich.

Application January 28, 1937, Serial No. 122,703

4. Claims.

Our invention relates to a new and useful improvement in a pneumatic tool of the rotary type, whereby a driven shaft to which a suitable tool such as a grinding wheel or the like may be attached is rotated. While the invention is referred to as a pneumatic tool and is primarily intended for being driven by air, it will appear obvious from the description of the invention that it might also be driven by steam or other suit- It is an ob ject of the present invention to provide a tool of this class so constructed and arranged that the maximum. speed of the tool is automatically governed so that when the tool is lifted from the work piece upon which an operation is being performed a racing of the tool will be prevented.

' Another object of the invention is the provision of a tool of this class so arranged and constructed that by simple and easy adjustment the volume of driving fluid delivered to the tool may be regulated.

Another object of the invention is the provi sion of a rotor slidably mounted on a rotatable shaft which it serves to rotate, and so arranged and constructed that, when in operation, the sliding of the rotor onthe shaft will be controlled by the speed of rotation.

Another object of the invention is the provision in a tool of this class of a circular'rotor mounted on the shaft which it drives and cooperating with a jet ring or fluid distributor so-that the fluid will be delivered to the rotor around its periphery.

Another object of the invention is'the provision in a tool of this class of a rotor having a plurality of inwardly directed passages opening outwardly at its periphery and communicating at their inner ends with laterally directed inclined passages through which the driving fluid may be delivered.

Other objects will appear hereinafter.

The invention consists of the combination and arrangement of parts hereinafter described and claimed.

The invention will be best understood by a reference to the accompanying drawing which forms a part of this specification and in which,

Fig. l is a longitudinal central sectional view of theinvention.

Fig.2 is a fragmentary sectional View taken on lined-2 of Fig. l.

Fig. 3 is a fragmentary sectional view taken on line 33 of'Fig. 1.

Fig.4 is a sectional view taken on line 4-4 of Fig. l'with parts broken away.

Fig. 5 is a sectional view taken on line-5-5 of Fig. 1.

Fig. 6 is a side elevational view, slightly reduced, of the jet ring.

Fig. 7 is a fragmentary sectional view taken on line 7- of Fig. 1.

As shown in the drawing, the invention comprises a housing having an elongated neck l5 which serves as a hand hold and which terminates in the enlarged cup-shaped portion I6. Extending axially of the housing is the driven shaft ll, on the enlarged portion 18 of which is mounted a bearing l9 held in position by the nut 20 and clamped against the nut 20 by the collar 25 which is threaded on the end of the neck I5. On the end of the shaft is a suitable collet head 22 whereby a suitable tool such as a grinder, cutting tool or the like may be mounted.

The shaft ii is also journaled in the bearing 23 and mounted on the rear end of the shaft I1 i a bushing 24 having at one end the head 25 which is provided with the tapered surface 26 and in which are formed spaced openings 21 in each of which is positioned a ball 28 adapted to engage the inclined surface 29 formed at one end of the collar 30. This collar is slidably mounted on the bushing 24 but is non-rotatable thereon. The collar 3|] and the bushing 24 are keyed by the key 32 and the bushing 24 is mounted on the shaft IT. as a press fit so that the collar and the bushing 2- 5 both rotate in unison with the shaft ii. A cup-shaped fitting 33 is threaded on the inner end of the shaft I! and overlies the end of the collar 39. A spring 34 is positioned about the bushing 24 in embracing relation and engages at one of its ends with the end of the collar and at its other end with, the inner face of the fitting 33. Consequently the sliding of the collar 36 on the bushing 24 toward the right of the drawing would be against the compression of the spring 36, so that the spring 34 would normally retain the parts in the position shown in Fig. Fixedly mounted on the collar 30 is a rotor 35 which is caused to rotate by a fluid under pressure delivered thereto. As the rotor rotates and carries with it the shaft H, the centrifugal force operating on the balls 28 would have a tendency to force them outwardly. When this force becomes sufiiciently strong resulting from the increased speed of rotation the balls will move outwardly and force the collar 30 to move toward the right of the drawing against the compression of the spring 34, thus diminishing the quantity of fluid delivered to the rotor and therefore reducing the speed of the rotor.

Positioned fixedly within the housing [6 so as to embrace the rotor 35 is a cylindrical member which may be termed a jet ring 36. Formed in the jet ring at spaced intervals are the axially extended passages 31. Each of these passages 37 communicates with an arcuate groove 39 formed in the periphery of the jet ring 36. Each of these grooves 39 terminates centrally of the jet ring 36 and communicates with the chordally directed passage All which opens through the inner surface of the ring 36.

Formed in the periphery of the rotor 35 is a plurality of spaced recesses M, each of which communicates with a pair of oppositely directed passages 42 and 53, which are directed at an incline to the faces of the rotor 35 and outwardly toward the periphery. Thus air delivered through the passages 3i will be projected outwardly through the passages ii and 43 and effect a rotation of the rotor 35. In order to permit the exhausting of the air passing outwardly through the passages at, we have cut openings 44 as spaced parts on the ring 36, leaving a body 45 of the material spanning the cut away portion and this body 35 is the portion of the ring 36 which registers with the rotor Threaded on the housing it and serving as an end wall or a closure therefor is the cap 55 in which are formed the pockets 4'5. Positioned in the pockets l? is a spring 48 and a ball 4% adapted to bear against the inner face of the adjusting plate 56 which is held in position by the spring band 5% snapped on the hub 52 of the cap il'z. This adjusting plate 56 carries the inwardly projecting stud 53 which projects through the arouate slot 54 formed in the cap 46. This stud projects into a pocket 55 formed in the control valve 56. This control valve is circular and fits fairly snugly within the housing 56. Formed centrally of the control valve 53 in one face thereof is a recess 5'? which communicates by passages 58 with the slots 5% 68 and 5!, which open through one face thereof. Projecting outwardly from one face of the valve 5% is a circular flange engaging in a circular groove 63 formed on the inner face of the cap 45. The construction is such that upon rotating the plate 5f] the valve 56 may be rotated.

Formed in the hub 52 is a threaded opening 64.

to which may be attached the end of the pressure line through which the driving is conducted. This driving fluid will pass through the pipe 65 mounted in the cap it, this pipe 65 traversing the recess 6% formed in the hub 52. A filling passage 6! closed by the plug 68 is provided for delivery of oil into the passage or recess 66. This oil may be drawn through the openings 69 and '50 into the passage 5? so that the air delivered to the jet ring 36 will be lubricated.

When the plate 5:? is rotated to a certain posi-- tion, the slot 6i will be in registration with one of the passages 3i and the slots 59 and will not be in registration with any of the passages 31, so that the driving fluid will be delivered to the rotor through only one of the passages 3?. Should it be desired that more power be transmitted to the rotor the plate 5E3 may be rotated until the slot 60 is also brought into registration with one of the passages 37!, the slot ti being of sufficient length to permit this rotation without disturbing the delivery of fluid through the slot iii. In such a position of control or adjustment, the fluid will be delivered to the rotor through a pair of passages 31. Should additional fluid be desired so that additional power would be transmitted to the rotor the plate 50 may be turned to bring the slot 59 into registration with one of the passages 37 while, at the same time, the slots 60 and iii would remain in registration with their respective passages 31 and thus the driving fluid would be transmitted to the rotor through three of the passages 31. In this way, there is provided a simple and easily operated means for adjusting the amount of fluid under pressure delivered to the rotor.

When the tool is operating, the power required to drive the tool at the required speed would, of course, depend upon the nature of the tool mounted on the head 22 and the nature of the work being done. On some types of work greater power would be required than on others and the adjusting feature referred to affords a meansv of regulating this power. The ball t9 would at each position of adjustment snap into a shallow recess it formed in the inner face of the plate 50.

When the tool is operating and it is lifted from the work the shaft I! would be, of course, be relieved of the strain or resistance which the operation would exert and the shaft ['1 would naturally have a tendency to race. When the increased speed reaches a predetermined amount. the balls 23 moving outwardly would shift the collar to the right carrying with it the rotor 35, thus moving the recess 41 gradually out of alignment with the jet passages 40 and therefore reducing the amount of fluid under pressure delivered to the rotor. Consequently, when the tool is lifted from the Work piece, its speed of rotation cannot pass a predetermined speed as the control automatically functions.

With a tool constructed and arranged in this manner, it is believed that a very efficient easily operated tool of this class is provided, in which a maximum of control and regulation is obtained while, at the same time, the device is compact and yet durable.

While we have illustrated and described the preferred form of construction, we do not wish to limit ourselves to the precise details of structure shown, but desire to avail ourselves of such variations and modifications as may come within the scope of the appended claims.

Having thus described our invention, what We claim as new and desire to secure by Letters Patent is:

1. In a machine of the class described a housing; a rotatable shaft projected into said housing; a rotor mounted on and rotatable in unison with said shaft; a fluid delivery member embracing said rotor and having a plurality of passages formed therethrough centrally thereof in registration with said rotor and communicating with passages opening through one of its end faces; means for delivering fluid to said passages opening through said end faces, a portion of said fluid delivery member being cut away at opposite sides of said rotor and provided with a cut away portion spanning said rotor for permitting escape of fluids from one side of said rotor.

2. A tool of the class described, comprising: a housing; a rotatable shaft projected into said housing; a rotor mounted on and rotatable in unison with said shaft and having a plurality of spaced recesses formed in its periphery, each of said recesses communicating at its base with a passage opening at one of the side faces of said rotor and directed at an incline to said shaft and inclined outwardly toward the periphery of said rotor; an annular member snugly embracing said rotor and having an axially directed passage opening through one of its end faces and communicating at its inner end successively with the recesses in the periphery of said rotor upon rotation of said rotor; a valve positioned in said housing and having a plurality of passages formed therein adapted for communicating with the ends of said passages in said annular member; means for conducting fluid under pressure to the passages in said valve, said valve and said annular member being rotatably, relatively movable for regulating the volume of fluid delivered to the passages in said annular member.

3. A tool of the class described, comprising: a housing; a rotatable shaft projected into said housing; a rotor mounted on and rotatable in unison with said shaft and having a plurality of spaced recesses formed in its periphery, each of said recesses communicating at its base with a passage opening at one of the side faces of said. rotor and directed at an incline to said shaft and inclined outwardly toward the periphery of said rotor; an annular member snugly embracing said rotor and having an axially directed passage opening through one of its end faces and communicating at its inner end successively with the recesses in the periphery of said rotor upon rotation of said rotor; a valve positioned in said housing and having a plurality of passages formed therein adapted for communicating with the ends of said passages in said annular member; means for conducting fluid under pressure to the passages in said valve, said valve and said annular member being rotatably, relatively movable for regulating the volume of fluid delivered to the passages in said annular member; and means accessible exterior of said housing for effecting relative movement of said valve and said annular member.

4. In a. tool of the class described, a housing: a rotatable shaft projected into said housing; a rotor mounted on and rotatable in unison with and axially movable of said shaft; a spring for normally resisting movement of said rotor on said shaft in one direction; a stationary delivery member having a plurality of passages formed therein for delivering fluid to said rotor, said rotor having a plurality of spaced recesses formed in its periphery for reception of fluid delivered by said delivery member; a plurality of curvilinear members loosely mounted on said shaft in circumferentially spaced relation to each other and adapted upon rotation of said shaft in excess of a predetermined speed for moving outwardly from the periphery thereof; and means cooperating with said curvilinear members, upon their outward movement, for efiecting axial movement of said rotor relatively to said shaft against the compression of said spring.

JAMES A. MONNIER.

CORNING S. BRUSH.

Images