US 2634640 A
Description (OCR text may contain errors)
April 14, 1953 H. c. PEDERSEN 2,634,640
GEAR-OPERATED, PREDETERMINED TORQUE RELEASE WRENCH Filed Nov. 30, 1949 2 SHEETSSHEET 1 Aprifl M, 1953 H. c, PEDERSEN 296349540 GEAR-OPERATED, PREDETEIRMINED TORQUE RELEASE WRENCH Filed Nov. so, 1949 2 SHEETSSHEET 2 ATTORNEYS a Patented Apr. 14, 1953 GEAR OPERATED PREDETERMINED TORQUE RELEASE WRENCH Harry 0. Pedersen, Royal Oak, MiclL, assignor, by
direct and mesne assignments, to Clyde Engineering and Manufacturing Corporation, Royal Oak, Mich, a corporation of Michigan Application November 30, 1949, Serial No. 130,287
This invention relates to power operated Wrenches, the primary object of the invention being to provide means for automatically disconnecting the power from the wrench shank when the tool has operated to tighten a nut upon a bolt to predetermined torque setting.
An important object of the invention is to provide means for moving the coupling members to move the teeth of the coupling out of contact with each other after the nut driven by the wrench has been tightened as required, thereby eliminating wear on the teeth due to the retation of the coupling members and teeth during overrunning of the clutch.
Another object of the-invention is to provide means for adjusting the automatic throwout mechanism so that the throwout mechanismwill operate when a nut has been tightened upon a bolt to apredetermined distance or torque setting. 1
Still another object of the invention is to provide an improved automatic power operated wrench which will be automatically rendered operable by the operator in placing the wrench upon a nut disposed on a bolt and applying pressure upon the wrench in the direction of the nut.
With the foregoing and other objects in view which will appear as the description proceeds, the
invention consists of certain novel details of construction and combinations of parts hereinafter more fully described and pointed out in the claims, it being understood that changes may be made in the construction and arrangement of parts without departing invention as claimed.
Referring to the drawings Figure 1 is a longitudinal sectional view through a power wrench, constructed in accordance with the invention.
Fig. 2 is a sectional view taken on line of Fi 1.
Fig. 3 is a sectional view taken on line 33 of Fig. l.
Fig. 4 is a side elevational view of the main or body portion of the wrench.
Fig. 5 is a sectional view through the upper portion of the wrench.
Fig. 6 is a perspective view pling member of the tool.
Referring to the drawings in detail a work turning element A of the wrench comprises a main shaft 5 carrying adjacent one end a driven head B. The shaft 5 is provided intermediate its ends with a threaded portion 6 with which illustrating the coufrom the spirit of the an adjustable stop collar I is threadedly engaged. The collar 1 is provided with threaded openings 8 and wrench openings 9, whereby the collar may be adjusted longitudinally of the main shaft 5 and held by means of set screws I0 positioned within the threaded openings 8.
This stop collar 1 provides a seat for one end of a compression coiled spring .II which encircles the shaft 5 and the opposite end of said coil spring bears against a bearing C comprising-a steel washer I2 that in turn frictionally engages the bronze washer [3 that rests against a steel washer I 4. The steel washer I4 is provided with an enlargement l5 that fits within a recess it formed in the lower end of a collar I! which encircles the shaft 5 and forms a driving head D which is rotatable about and longitudinally" movable relative to the shaft or work turning element A.
Surrounding the collar [1 and fixed thereto'as' by means of a key 22 is an outwardly extending annular ring 2| having formed in the end there of adjacent the driven head B peripherally spaced recesses 18- of substantially rectangular form.
These recesses open through the adjacent end of the ring 2| for the reception of peripherally spaced fingers 28 which are carried by a driving element 26 which is mounted for rotation on the shaft 5 adjacent the driven head B on the side thereof remote from the driving head D; A-suitable anti-friction bearing 33 provides the-support for the driving element 26 on the-shaftil' Carried by the driving head D on the end thereof adjacent the driven head B is an annular row of tapered teeth 23 which as illustrated in Fig. 5 are adapted to mesh with cooperating teeth 24 on the driven head B. Said teeth 23 and being held in meshing engagement under the influence of the spring ll previously referred to. It will thus be seen that when the resistance to turning of the shaft 5 attains a predetermined value, the teeth 23 will ride against the inclined surfaces of the teeth 24 to cause a separation of the driving head D from the driven head B against the effort of spring ll. Formed in the ring 2| and extending radially therethrough adjacent one corner of each recess 18 is an arcuate recess [0 into which is fitted a roller 20. These rollers project radially outwardly beyond the periphery of the collar I1, and secured in any suitable manner to the ring 2! in encircling relation to and overlying portions of the rollers 20 is an annular retainer 32 by means of which the rollers 20 are held in proper position in the recesses l9. As shown the rollers 20 lie in the path of the fingers 28 so that When turning effort is applied to the driving element 26, the fingers will engage the rollers and cause the driving head D to rotate in unison with the driving element 26.
Carried by the fingers 23 and formed at the junctions of the trailing walls of the recesses and the ends of the fingers remote from the driving element 26 are inclined cam surfaces 29 which, when the teeth 23 and 24 approach maximum separation against the efiort of the spring I ll, engage the peripheral surfaces of the rollers 20 to exert further separating effort on the parts to completely separate the teeth so that the driving head D may rotate without turning the work turning element A and the points of the teeth 23 and 24 will be protected from wear. The driving element 26 is provided on theend thereof remote from that carrying the fingers 28 with clutch teeth 38 which are adapted to be engaged by the teeth 39 of a clutch member 40 which is mounted for rotation on an extension '42 of the shaft andis coupled to a conventional driven gear 48 which is operatively connected through the drive gear 49 to the prime mover of the device. I
In use it will be seen that as the teeth 39 of the clutch 40 engage the teeth 38 of the driving element 26, assuming of course that the prime mover is in operation, power will be transmitted through the fingers 28 to the head D by engagement with the rollers 20. In this driving operation, the teeth 23 will be held in mesh with the teeth 24 under the influence of the spring ll so that driving effort will be transmitted to the shaft 5. When the resistance'of the shaft 5 to turning attains a predetermined value, the inclined faces of the teeth 23 and 24 will tend to cause the driving head D to move longitudinally on the shaft 5 against the efforts of the spring; -I I until the inclined cam numbers 29 on the fingers-28 attain a position-which will cause them to rideon the rollers and move the head D further against the effort of the spring H until the points of teeth 23 and 24 are free from one another to thus enable the driving head D to rotate without imparting an rotary motion to the driven head B.
While in the foregoing there has been shown and described the preferred embodiment of this invention it is to be understood that minor changes in the details of construction, combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention as claimed.
Having thus described the invention, what is claimed is:
1. In a power driven wrench, a main shaft, a driving member having teeth, keyed on the shaft, adriving sleeve loosely mounted on the driving member, said driving sleeve having extensions, a collar rotatably mounted on the main shaft, said collar including an inner section having teeth meshing with the teeth of the driving member, coupling the main shaft with said collar, said collar having cut away portions extending from one edge thereof, into which the extensions extend, bearings mounted within the cut away portions, said extensions engaging said bearings and rotating the collar'and main shaft as the driving sleeve rotates, an adjustable tension spring encircling a portion of the main shaft and bearing against the collar, thereby normally urging the collar towards the driving sleeve and connecting the teeth of the collar and driving sleeve, said extensions having rounded corners adapted to ride over the bearings, thereby disengaging the teeth of the driving member and collar, said extensions resting on the bearings and holding the teeth of the driving member and collar separated during continuous rotation of said main shaft.
2. In a torque Wrench in which driving power applied to work is automatically discontinued when the resistance of the work to turning attains a predetermined value, said wrench comprising an elongated work turning element, a driven head fixed to said element, an annular row of teeth having oppositely inclined faces carried by and extending longitudinally from one side of said driven head, a driving head mounted on said work turning element forro tation thereabout and movementlongitudinallythereon adjacent the driven head, an annular row of teeth having oppositely inclined facescarried by and extending longitudinally from the side of the driving head adjacent the driven head, a collar mounted on the Work turning element in spaced relation to the driving head for adjustment longitudinally on said work turning element, a compression coiled spring encircling the work turning element and bearing on the collar and on the driving head for yieldingly holding the teeth of the driving head in mesh with those of the driven head whereby when the resistance to turning of the work turning element attains a predetermined value the teeth on the driving head will ride on the teethof the driven head against the eifort of the spring and turning efiort on the work turning element will be discontinued despite the continued rotation of the driving head, rollers carried by and extending radially outwardly from the driving head, fingers carried by the work turning ele ment for rotation thereabout, saidfingers-extending parallel with said Work turning element and being adapted to engage the 'rollers for driving the driving head, and cam surfaces on the fingers for engaging the rollers and moving the driving head against the efiort of the spring to completely disengage the teeth as the approach disengagement. l
HARRY c. PEDERSENQTY References Cited in the file' of this patent UNITED STATES PATENTS Great Britain Oct. 24, 1934