US2734413A - Chuck and ratchet mechanism - Google Patents

Description

14, 1956 M. s. DUNKELBERGER 2,734,413

CHUCK AND RATCHET MECHANISM Filed April 18, 1950 R m m N EE vn w JIEA Un ted. States, aw

. This invention relates to a tool for operating various types of devices such as screw drivers, drills, socket wrenches, and the like.

A large number of ratchet mechanisms have been de vised from time to time for use in operating screw drivers and the like, but these have either involved a large number of delicate parts or have otherwise been unsatisfactory The problems of providing a satisfactory ratchet type of operator for a screw driver is very ditficult because of the tendency of the ordinary screw driver to slip out of the slot in the screw and because of the need for applying a strong downward pressure while rotating the screw driver. It is an object of this invention to provide an improved combination screw driver and screw driver holder or operator which makes it easy to hold the screw driver in place in the eye of the screw during the screw driving operation.

It is another object of this invention to provide an inexpensive, yet durable, tool which may be used for a large number of different uses and which operates in an improved manner. More particularly, it is an object of this invention to provide an improved type of ratchet drive which includes a simplified means for selectively adjusting the ratchet for rotating a tool in either direction of rotation or for rotating the tool in both di rections.

Another object of this invention is to provide an improved pawl and pawl mounting arrangement.

Another object of this invention is to provide an improved relationship between a ratchet type of crank and thetool to be operated thereby;

"Still another object of this invention is to provide an improved form of chuck for use in supporting the tools. I

I Other objects and advantages reside in the construction of parts, the combination thereof and the mode of operation, as will become more apparent from the following description.

I In the drawings:

.Figure 1 is a side elevational view; I

.Figure, 2 is an exploded perspective view showing the construction and arrangement of the ratchet mechanism;

Figure 3 is a plan view of the ratchet mechanism with the'cover removed;

'Figure 4'is a plan view with parts broken away to show the ratchet in its neutral position;

' Figure 5 is a fragmentary sectional view showing the chuck and its relationship to a tool mounted in the chuck;

Figure 6 is aside elevational view, with parts broken away, showing a drill unit mounted in the chuck;

.Figure. 7 is a perspective view of an adapter for use mounting a socket wrench in the chuck shown in Figure 5 and 6.

Figure 8 is a perspective view of the lower end-piec of the screw driver; and

Figure 9 is a fragmentary elevational view showing the pawl supporting means.

" Referring now to. the drawings wherein I have shown a prferred' embodiment of my invention, reference numeral 10 generally designatesa ratchet lever having a handle 12 rotatably mounted adjacent the one end thereof for use in imparting rotation to the main shank 14 through a ratchet drive in a manner to be explained more fully hereinafter. A chuck or socket 16 is secured to the lower end of the shank 14 and is adapted to interchangeablyreceive a variety of types and sizes of tool members, such as screw drivers, drills, socket wrenches, Allan wrenches, and the like. i

A specially designed pressure handle 20 is rotatably' the work. The lower portion of the pressure handle is" provided with a relatively wide flange 22 which makes it possible to exert a downward pressure without danger of one's hand slipping. The upper end of the handle does not have such a flange and is purposely so designed that irrespective of how large ones hand is, one can get a firm grip-onthe pressure handle. A sleeve 23, which is disposed between the handle 20 and the ratchet lever' 10, holds the pressure handle against the upper end ofthe chuck as shown. It should be noted that the handle 20 is placed next to the chuck, whereby it is possible to accurately'guidethe tool held by the chuck.

Generally speaking, no amount of downward pressure will keep a poorly designed screw driver from slipping out of place. The most common forms of screw drivers have a straight shank with a fixed handle arranged directly in alignment with the shank, so as to enable the user to align the screw engaging portion with the eye of the screw. Even with these conventional screw driver's,

it is ditficult to keep the axis of the screw driver properly lined up with the axis of the screw. In the screw driver construction shown in the drawings, the screw engaging portion 24 is pivotally mounted on a holder 26 by means of a pin 28 arranged as shown. A slight amount of clearance is provided between the upper end of the screw engaging portion 24 and the holder 26, so as to permit limitedoscillation of the portion 24 relative to the holder 26." Furthermore, the lower end of the screw engaging portion 24 is slightly curved as shown at 30. By virtue of this curved arrangement, a slight misalign-- ment of thescrew driver relative to the axis of the screw does not have as much tendency to disengage the screw driver from the slot in the screw.

As indicated in the drawings, the lower end of the screw driver has been ground, so as to form a somewhat wedge-shaped screw engagingmember which further tends to prevent the screw driver from slipping out of the slot in thescrew head. By virtue of this latter construction, operation of the screw driver tends to pull the screw driver downwardly in the slot rather than upwardly as in the conventional screw driver designs. Thus, a

.screw driver of the type disclosed herein is especially well suited for use in a crank type of screw driver wherein the tendency for misalignment between the shank of the screw driver and the axis of the screw is somewhat as the holder.43 of Figure 6.

45, so. as-to. rotate. in unison. with thewshanlt. 14; at all: times; Aelatching doggortrigger 42 is pivotally supportediwithin" the. slot 44%provided.,in-.the; body membe1t40; As shown: in, the drawings,, the.- body member: is cutaway; as in dicated at 46;.so as;to'pr0videaz suitable mounting flange for the: pin; 48 onwhich the trigger 42 is; pivotally: sup.- ported. The trigger 42is.providedwith: a sean-5,0-which is adapted to engage the shoulden 52- formed on eachof the tools to be usediinthe: chucle. The shoulder 52' is formed by: cutting: a circumferentially extending; groove in the: shank. of. each; of" the tools, as shown. The: upper end of each: tool is; provided-with a: semicircular; lug or projection 54. which. is: complementary to a. similar. semicircular; lug; or. projection. 56; formed integrally with. the lower endofrthe mainshank 14;

The trigger. 42 is. at? all times .biasedinto, latchingz posia tionby-the spring 60,-.and in order to. remove atool from the chuck, it isnecessary to press. on the projecting, end ofi, thetrigger so as to. disengage thesear from .the shoulder 52. In order. to support, the spring 60 within the body member,- 40, ahole; 62- is drilledv into the body member 40,,aszbest" shown in Figure 6. The diameter of the hole 62 is-slightly greater than thewidth of the slot 44,,so that a washer. 6.4 placed in the. bottom of. the hole: 62- serves to, support, the inner; end of the spring,- By virtue of this arrangement, thepivot. pin 48 not only-holds.the trigger- 42, iniassembled relationship but also serves to holdv the. spring 60 and thewasher- 64. in assembled relationship. The projecting; end 61 on the trigger 42 strikes. against theend-surface 63' of the slot.- 44 and. limits the inward movement of the sear portion 'of the. trigger.

Referringnowto-the ratchet mechanism which. is' used for transmitting power from the: handle 12ito-the shank 14, reference numerals70 and 72 designate the-upper and lower housing members. respectively of the ratchet assembly. Each of these housing members consists of an inexpensive sheet metal stamping which may beheld in assembled-relationship by, any suitable means, such as-the screws-.74 and the-bolt 76.which supports the handle 12. The upper end. of the.shank has secured thereto-a ratchet. member 78 which isdisposed between the'housing; members 70 and .72, as shown. Asingle ratchet: engag ing pawl 80- is slidably mounted between. the. housingmember-s70 and; 72 and is: adaptedtohavezits;innerend.

arranged to. engage the teeth onthe. ratchet member. 78.

The inner endof. thepawl 80 has its one side-bevelled, as indicated. at; 82, so thatin. a; first setting; of: thepawl, it will be shoved out of engagement with theratchet teeth.

as; the: pawl: is. rotated. inthe; one: direction. but will. positively engage the ratchet teeth if. rotatedLimthe:opposite direction. By rotatingthe pawlthrough 180? into a secondposition, one automatically, changes therdireetion in: which thepawh is etfcctiverto operate. Unlike ordinaryypawlsthc pawl'80 can,be set in. a neutral; position which is: midway between'the first and. second positions; just mentioned and-in this neutral positionzit: will transmit; power. to therteeth of the ratchet inbothdirections; of.r,o-

tation of the pawl. This is made possiblehythe-fact that the. bevelled portion82gfaces up rather than towards the teeth. of the ratchet when the-pawl isinrthe-ineutral POSl':

(i011. In this neutral position. the;straightqsidesofithe pawl engage the teeth, as shown in.Figure.4 of. thedrawings.

The pawl 8.0 i is biased into. engagement .with the-.ratchet member by nreans.of-.a.spri11g.84 whichhas its. one end abuttingagainst. the fixed spring. support 86 riveted or otherwise secured to the housing member 72, as shown. The outer or free end of the pawl is provide'd'with a recess ss-rar receiving, the one end ofthe spring 84. In

order; to facilitate free relative rotation between the spring and the pawl; a ball-bearing eiementSNI-has been'provided, as shown, at the inner end'of'the recess 88.

In order to set the pawl so as to operate the-ratchet in the desired direction, the pawl is provided with a finger engaging wheel or knurled disc 92 which is adapted to project through the slot 94 in the housing member 70. A lug 96 is formed on the disc and is adapted to cooperate with the housing member 70, so as to hold the pawl in any one of the three desired positions. The one wall of the slot 94 is provided with a notch 98 for holding the pawl in the neutral position. The lug. 96 rests against the inner side of the housing in the other two positions of the pawl.

The pawl 89 is rotatably supportedbetween a. pair of complementary floating bearing elements 100' and 102, as shown. These bearing elements areformed from sheet metal stampings which are held in place against sidewise or endwise movement within the slots 104 formed in the housingmembers 70 and. 72. Projecti0ns105 formedton the elements 100and. 102. limit the outwardimovementof the bearing elements in the slots 104;

As best illustrated in Figuresv 2 and 9,,the arms of' the bearing elements 100 and 102 are. provided with inter lockingprojections and.112 which serve to, hold the bearingelements in proper alignment with, one. another. It will be observed that one arm of each of the stampings' is provided with asubstantially, U-shaped bearingslot 114. and that the complementary arm isprovided with. a flat bearing surface 116. By virtue of this construction, it isobvious that a limitedv amount of' misalignmentbetween the. opposed bearing elements willnot cause the pawl to.

bind; Thus, slight variations in the. dimensions of the parts. will not. cause the. pawl to bind..

In order to limit the rotation of the pawl 80,.theone: bearing element 102 has secured. thereto- (-such. as. by spot welding) a U-shaped stamping element 106 which hasits upper edges arranged to limit the rotational. movement of the dog 108'which is struck .up from the pawl 80,. as shown.

Although the preferred embodimentof the device, has

been described; it will beunderstood that within the. purviewv of this invention'various changes may be made in the form, details, proportion and arrangement of' parts, the combination thereof and mode of operation, which generally. stated consist in-a device capable of'carrying out the objects set forth,.as. disclosed. and defined in.

the shank being attached to the ratchet wheel at'the center portion thereof and concentric therewith, the ratchet wheel beingprovided with straight-sided teeth, a pawl for engaging saidteethslidably and rotatably. supported withinthe hollow handle and normal to the longitudinal" axis of'the shank, a plurality of fioatingbearing elements. carried by the handle and supporting the pawl, a spring biasing said pawl into engagement with the ratchetwheeh,

one end of the pawlbeing provided witha circular recess formed therein, a ball bearing partiallydisposed'within the'circul'ar recess and engaged by oneend ofthe'spring, the-other'end of the spring engagingone oftlie hollow half sections; the pawl having OIIBSidEthCI'COf'bCl/Cllhd to slidably engage the teeth, the pawl also having a.

straight. side, and a' knurled knob attached tor the pawl'.

for adjusting the pawl.

References Cited in the file-of this patent UNIT ED. STATES. PATENTS 12,198 Everett Jan; 9,: 1.855: 67,014 Ayres- July;'23-,..1867 207,964: Hart ....Sept.'.10; 1878 (Other references on' following page) 5 UNITED STATES PATENTS Abrams Sept. 9, 1879 Crockford Jan. 13, 1880 Crecilius Jan. 9, 1883 Murphy July 16, 1889 Kent Dec. 17, 1889 Pratt Oct. 21, 1890 Dawson July 21, 1891 Chellis Sept. 25, 1900 Charleset a1. Ian. 6, 1903 Peterson Dec. 29, 1903 Mossberg Nov. 11, 1913 Carll May 4, 1915 Kremer June 19, 1917 6 Ayotte Nov. 1, 1921 Miller July 11, 1922 Morgan Aug. 8, 1922 Gormley Aug. 14, 1928 Flintermann July 14, 1931 Merriman Apr. 11, 1933 Lorenzer et a1. Apr. 9, 1935 Mayer June 25, 1940 3 Eastus Sept. 30, 1941 Detmers Mar. 31, 1942 West Apr. 20, 1943 Foreman May 2, 1950 Vosper June 27, 1950

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