US3791242A

US3791242A - Power operated wrench mechanism

Info

Publication number: US3791242A
Application number: US00808774A
Authority: US
Inventors: A Bartusch
Original assignee: Individual
Current assignee: Individual
Priority date: 1969-03-20
Filing date: 1969-03-20
Publication date: 1974-02-12
Anticipated expiration: 1991-02-12

Abstract

A motor operated wrench mechanism for imparting successive rotative movement to an object to which the wrench mechanism is applied. The wrench mechanism includes a motor which imparts reciprocational movement to a connecting rod through a worm gear eccentric crank shaft mechanism. The connecting rod imparts successive rotational movements to a ratchet gear through a driving mechanism including a plurality of driving pawls capable of varying the effective rotative driving stroke of the drive mechanism. A lost motion connection may be provided between the connecting rod and the ratchet drive mechanism to provide infinite variance in the length of the operative stroke of the wrench mechanism and to provide impacting actuation of the drive mechanism for breaking loose the object to be rotated.

Description

United States. Patent 1191 Bartusch Feb. 12, 1974 POWER OPERATED WRENCH 1,871,857 8/1932 Martois 81/5739 x MECHANISM 2,711,110 6/1955 Brame 81/58.]

[76] Inventor: Alexander P. Bartusch, 40333 i Central Ave coldspringsi Tex Prrmary Examiner-James L. Jones, Jr. 92343 [57] ABSTRACT [22] Filed: Mar. 20, 1969 A motor operated wrench mechanism for imparting PP 808,774 successive rotative movement to an object to which Related U.S. Application Data Continuation-in-part of Ser. No. 669,668, Sept. 21, 1967, abandoned References Cited UNITED STATES PATENTS 5/1956 Schneider 74/l42 X 6/193] Weaver..... 81/5739 6/1966 Medesha... .s1/57.13 12/1955 Blackburn ..s1/57.39x

the wrench mechanism is applied. The wrench mechanism includes a motor which imparts reciprocational movement to a connecting rod through a worm gear eccentric crank shaft mechanism. The connecting rod imparts successive rotational movements to a ratchet gear through a driving mechanism including a plurality of driving pawls capable of varying the effective rotative driving stroke of the drive mechanism. A lost motion connection may be provided between the connecting rod and the ratchet drive mechanism to provide infinite variance in the length of the operative stroke of the wrench mechanism and to provide impacting actuation of the drive mechanism for breaking loose the object to be rotated.

5 Claims, 8 Drawing Figures PATENTEUFEB 12 I974 SHEET 1 [1F 2 Alexander F. Bartusch /N VE N TOR A TTORNE Y iATENTED FEB l 2 I974 SHEET 2 (IF 2 FIGS Alexander P. Bartusch IN VE N TOR A TTORNE Y 1. POWER OPERATED WRENCH MECHANISM This is a continuation-in-part of applicants prior patent application serial number 669,668 filed September 21, 1967, now abandoned.

BACKGROUND OFTHE INVENTION This invention relates generally to a motor operated wrench mechanism which is capable of imparting rotational movement to an object to be rotated such as a hand wheel of a valve, a bolt to be tightened or loosened, or the like. This invention will be described particularly as it relates to the rotation of a valve hand wheel, but such specific use is not intended to limit the spirit or scope of this invention. This application will also be directed particularly to utilization of the invention in a portable valve actuating mechansim, but it is intended that this invention be capable of utilization in stationary valve operator mechanisms within the sprirt and scope of this invention.

Valves which are located in various processing or refining plants or are located on ocean going tanker vessels and the like are frequently positioned so that operation thereof is made difficult, especially if the valve requires extremely high breakloose or opening torque. It is therefore frequently found necessary to provide motor energized valve actuators for such valves because of the difficulty of opening and closing the same. Provision of motor energized valve actuators is gener-. ally an expensive proposition which could increase cost to an impractical degree. I

It is therefore a primary object of my invention to provide an improved motor operated wrench mechanism which may be portable in construction allowing utilization of a'limited number of wrench mechanisms for opening and closing valves.

It is another object of this invention to provide a novel motor operated wrench mechanism which is capable of being powered by various acceptable power means, such as electric or pneumatically actuated motors or internal combustions engines and the like.

Among the several objects of my invention is contemplated the provision of a novel motor operated wrench mechanism having the ability to rotate an object either clockwise or counterclockwise and also having the ability to loosen screwed parts which are substantially frozen in place.

the structures hereinafter described and the scope of which will be indicated in the appended claims.

In the accompanying drawings, in which two of various possible embodiments of the invention are illustrated;

FIG. 1 is a plan view of the invention having portions thereof broken away and illustrated in section.

FIG. 2 is a side view of the motor operated wrench mechansirn of FIG. 1, having a portion thereof broken away and illustrating the ratchet gear drive mechanism therof in detail.

FIG. 3 is a sectional view of the motor operated wrench mechanism of this invention taken along the line 3-3 in FIG. 1 and illustrating utilization of the wrench mechanism with a hand wheel adapter to operate the hand wheel'of a valve.

FIG. 4 is a fragmentary sectional view in plan illustrating a modified embodiment of this invention.

FIG. 5 is an elevation view illustrating a hand wheel adapter tool which is utilized with the motor operated wrench mechansim for opening and closing gate valves.

FIG. 6 is a fragmentary plan view illustrating a portion of a valve hand wheel in phantom and showing association of the ball spring catch structures of a hand wheel adapter tool to the valve hand wheel.

FIG. 7 is a sectional view taken along line 7--7 in FIG. 8 and illustrating a modified valve hand wheel adapter tool for utilization with the motor operated wrench mechanism.

FIG. 8 is a plan view of the hand wheel adapter tool of FIG. 7.

Briefly this invention concerns a motor operated wrench mechanism which utilizes a rotary motor such as an electric motor, pneumatic motor, or the like, which is disposed in driving connection with a worm gear capable of inducing rotation to an eccentric member. The motor driven eccentric imparts reciprocation to a connecting rod mechanism which in turn imparts successive rotational movements to a ratchet gear drive mechanism. The ratchet gear drive mechanism includes a plurality of driving pawls which may be of It is an even further object of this invention to provide a novel motor operated wrench mechanism which is provided in the form of a totally enclosed unit which is lubricated for life and is able to function efiiciently with various adapter tools such as nut and bolt sockets, valve hand wheel adapters, and the like.

It is another important object of my invention to pro vide a novel motor operated wrench mechanism which is portable and is of such size, design, and weight that it may be utilized effectively in restricted areas such as for the operation of valves located in small pits or in the holds of ships and the like.

Another object of my invention involves the provision of a novel motor operated wrench mechanism which is simple in nature, reliable in use, and low in cost.

The invention accordingly comprises the elements and combination of elements, features of construction and arrangement of parts which will be exemplified and operatively associated therwith. A stopping pawl is provided to prevent retrograde rotation of the ratchet gear and may include a plurality of steps thereon for limiting partial tooth retrograde rotation upon operation of the partial tooth driving pawls as will be described herein below. The ratchet gear includes internal splines which are adapted to mate with the external driving splines of a valve hand wheel adapter tool or the like. The internal splined connection of the motor operated wrench mechanism is accessible from either side thereof to achieve clockwise or counterclockwise rotation of the valve hand wheel without the necessity of providing an internal reversing mechanism. The motor operated wrench mechanism may also include a lost motion connection between the connecting rod and ratchet gear drive mechanisms thereof in order to provide for infinite variation in the rotational movement of the ratchet gear, especially during the initial phases of breaking loose an object to be rotated. The lost motion connection effectively develops an impacting condition which readily accomplishes initial breaking loose of the object to be rotated.

With reference now to the drawings for a more detailed description of my invention, in FIG. 1 I have illustrated a motor operated wrench mechanism illustrated generally at which includes a wrench housing 12 defined by a pair of opposed housing halves l4 and 16 maintained in assembly by a plurality of bolts 18. A rotary motor 20 is received within the housing 12 in such manner as to define a portion of the handle structure of the motor operated wrench mechanism. The motor is illustrated in the drawings as an electric motor but it is quite obvious that other rotary motor mechanisms such as pneumatic motors or internal combustion engines may be employed within the spirit and scope of this invention. The motor structure 20 is provided with a handle 22 which is grasped by personnel using the motor operated wrench mechansim. An electrical conductor 24 extends from a source of electrical energy through the handle structure of the motor and is connected to the electrical circuitry of the motor in conventional manner. Energization of the motor 20 is controlled by means of a conventional electrical switch, not shown, which is in turn controlled by a manually actuated button 26. The motor 20 is provided with a rotatable shaft 28 which is supported intermediate its extremities by an antifriction bearing 30 retained in a bearing aperture formed in the housing 32 of the motor. The bearing 30 is retained by a seal and bearing retainer 34 connected to the motor housing 32 by means of screws 36. The motor housing 32 is provided with a bearing support extension 38 in which is formed a bearing aperture 40 having a bearing 41 therein receiving the free extremity of the motor shaft 28. A worn gear 42 is disposed about the rotatable motor shaft 28 and is maintained in non-rotatable relation with the shaft 28 by a tapered pin 44extending through registering apertures in the shaft 28 and worm gear.

A crank shaft 46 is supported by

opposed antifriction bearings

48 and 50 retained within

bearing support bosses

52 and 54 defined internally of the

housing halves

14 and 16 respectively. A worm wheel 56 is disposed in concentric non-rotatable relation with the crank shaft 46 and is disposed in driving engagement with the worm gear 42 as illustrated in FIG. 1. The worm wheel 56 may be formed integrally with the crank shaft 46 or may be connected in non-rotatable relation therewith in any desired manner. As illustrated in FIGS. 1 and 2 of the drawings the worm wheel 56 is connected to the central portion 58 of the crank shaft 46 by means of a key 60 which is retained in registering keyways formed in the worm wheel and central portion of the crank shaft.

A pair of

eccentric members

62 and 64 are formed integrally with the crank shaft 46 about a common eccentrically located center and are disposed within apertures formed in a pair of connecting

rods

66 and 68 respectively. Bearing

members

70 and 72 are disposed within the connecting rod apertures and provide bearing engagement with the

eccentric members

62 and 64 respectively. The connecting

rod

66 and 68 are joined at one extremity thereof by means of screws 71 and are provided with registering openings which cooperate to define an elongated aperture 73 retaining a connecting shaft 74. The connecting shaft 74 is secured to one of the connecting rods 68 by means of a set screw 75.

As illustrated particularly in FIG. 3 the motor operated wrench mechanism includes a ratchet gear 76 which is supported by upper and

lower bearings

78 and 80 received within bearing apertures formed in

internal bosses

82 and 84 defined within the housing halves l4 and 16 respectively.

A ratchet drive mechansim illustrated generally at 86 in FIG. 3 is provided with upper and lower interfitting

drive segments

88 and 90 which are secured into assembly by means of a plurality of bolts 92. A plurality of dowl pins 94 are received within registering blind bores formed in the upper and lower drive segments in order to add structural integrity to the ratchet drive assembly 86. The

drive segments

88 and 90 retain

bearings

94 and 96 which define bearing apertures receiving the extremities of the connecting shaft 74. The ratchet drive assembly 86 is received in rotatable bearing engagement with exterior peripheral bearing surfaces forrned on bearing

members

79 and 81 which are retained on opposite sides of the ratchet gear 76. The ratchet drive assembly therefore is freely rotatable within the housing 12 upon linear movement of the connecting

rods

66 and 68.

A plurality of driving pawls 98 are pivotably connected to the ratchet drive assembly 86 and are biased outwardly into engagement with the teeth 100 of the ratchet gear 76 by a plurality of compression springs 102. A stop pawl 104 is pivotally retained within a boss 106 formed integrally with and internally of the housing 12. A compression spring 108 is retained within a spring recess formed in the housing and biases the stop pawl 104 into engagement with the teeth 100 of the ratchet gear 76. The stop pawl is provided to prevent retrograde rotation of the ratchet gear as the ratchet drive assembly 86 is being rotated counterclockwise as illustrated in FIG. 1 by the connecting

rods

66 and 68. As the ratchet drive assembly 86 rotates counterclockwise as illustrated in FIG. 1 the driving pawls 98 will advance the ratchet gear 76 counterclockwise the distance of one or more ratchet teeth depending upon the stroke of the connecting

rods

66 and 68. As the ratchet drive assembly 86 is rotated clockwise the driving pawls 98 will be moved clockwise into engagement with other teeth of the ratchet gear 76 while the stopping pawl 104 prevents retrograde rotation of the ratchet gear.

The ratchet gear is provided with female splines 110 which receive the male spline 112 of a valve hand wheel adapter tool illustrated generally at 114 in FIG. 5. The adapter tool 114 is provided with a ball spring catch 116 which locks the male splines 1 12 into driving engagement with the female splines 110 of the ratchet gear. The adapter tool 114 is also provided with a plurality of depending fingers or lugs 118 each being provided with a ball catch mechanism 120. The fingers or lugs 118 of the adapter tool 114 are received between the spokes 122 of a valve hand wheel 124 in such manner that the ball spring catches engage the spokes in order to prevent inadvertant disassembly of the adapter tool from the hand wheel in the manner illustrated in FIG. 6.

With reference now to FIGS. 7 and 8 an alternate embodiment of my hand wheel adapter tool is illustrated generally at 128 which includes a lug adjustment plate 130 having a shank 132 received within a central aperture 134 formed therein. The shank 132 is provided with male splines 136 which are received by the female splines 110 of the ratchet gear 76. The shank 136 may be welded or otherwise fixed to the plate 130 as indicated at 138 in order to achieve positive driving connection between the shank 136 and the plate 130.

With reference particularly to FIG. 8 the plate 130 is provided with a plurality of radiating elongatedadjustment slots 140 in which are received adjustment bolts 142 having enlarged head portions 144 including 0pposed flat surfaces 145 which cooperate with the walls of the slots 140 to prevent rotation of the bolts within the slots. The bolts 142 are provided with upper flanges 146 which are larger than the width of the slots and which engage the upper surface of the plate 130. Hand wheel spoke engaging sleeves 148 are received about each of the bolts 142 and are maintainedin assembly with the bolts by a plurality of nuts 150. The nuts 150 may be loosened and the bolts 142 along with the spoke engaging sleeves 148 may be adjusted radially within limits defined by the slots 140 to enable the hand wheel adapter tool 128 to receive valve hand wheels of different size and configuration.

With reference now to FIG. 4, which illustrates a modified embodiment of my invention, a motor operated wrench mechanism, illustrated generally at 152, includes a housing 154 of essentially identical configuration as compared to the housing illustrated in FIGS. 1 through 3. A motor, not shown, is received by the housing 154 and is adapted to impart rotation to a worm gear 156 received by the motor shaft 158. A worm wheel 160 is driven by the worm gear 156 and imparts rotation to upper and lower integral eccentric members l62'formed on a crank shaft 164 on either side of the worm wheel. A connecting rod 166 having a bifurcated connector portion 167 is maintained in assembly with the upper and lower eccentrics 162 by connecting rod caps 168 which are retained in assembly with the upper and lower eccentric connector portion of the connecting rod by 'a plurality of bolts 170. A sleeve bearing 172 is interposed between the crank shaft and the eccentrics for the purpose of preventing wear of these parts.

A ratchet gear 174 is rotatably supported by upper and lower bearings 176 which are retained by the housing halves in the same manner as the

bearings

78 and 80 are retained by the

housing halves

14 and 16 respectively as illustrated in FIG. 3. The ratchet gear 174 is provided with female splines 178 which receive the male splines of an adapter tool in driving engagement therewith.

A ratchet drive assembly, illustrated generally at 180 in FIG. 4, is rotatably retained within the housing 154 by bearing members inthe same manner as the ratchet drive assembly 86 is rotatably supported-by the upper and

lower bearings

79 and 81 as illustrated in FIG. 3. The ratchet drive assembly 180 includes upper and lower drive segments which are retained in interfitting assembly and which cooperate to retain a plurality of driving pawls in pivotal relation therewith. The driving pawls include a plurality of long pawls 182 and a plurality of short pawls 184 which are biased into engagement with the teeth 186 of the ratchet gear 174 by a plurality of compression springs 188. In the event the ratchet drive assembly 180 is rotated a distance of one or more teeth in a counterclockwise direction before reversing the long drive pawls 182 upon reversing will be rotated clockwise into engagement with other teeth 186 of the ratchet gear 174. In the event the ratchet gear 74 is not driven counterclockwise a distance of at least one tooth by the ratchet drive assembly 180 upon counterclockwise rotation thereof, the short driving pawls 184 are capable of movement into driving relation with other ratchet gear teeth 186 upon partial clockwise rotation of the ratchet drive assembly. It is seen therefore that upon full stroke rotation and counter rotation of the ratchet drive assembly the long driving pawls 182 will drive the ratchet gear 174 and the short driving pawls 184 will not function. In the event however that rotation and counter rotation of the ratchet drive assembly is less than a full tooth distance the short driving pawls 184 will provide the driving function and the long driving pawls 182 will remain substantially inoperative. While two sets of long and short driving pawls are illustrated in FIG. 4 of the draw ings it is intended that other sets of driving pawls of varying length may be utilized within the spirit or scope of this invention to provide for less than full tooth driving capacity of the ratchet drive assembly.

A stop pawl 190 is pivotally supported by a boss 192 formed internally of the housing 154. The stop pawl 190 is biased into engagement with the teeth 186 of the ratchet gear 174 by a compression spring 194 retained within a spring recess in the boss 192. The stop pawl 190 is provided with at least one step defining a second tooth engaging shoulder 196. In the event the ratchet gear 174 is rotated counterclockwise a distance of at least one tooth the extreme end portion of the stop pawl '190 will engage a ratchet gear tooth to prevent retrograde rotation of the ratchet gear when the ratchet drive assembly is reversed. In the event the ratchet gear 174 should be rotated counterclockwise a distance less than a full tooth the step or shoulder 196 of the stop pawl 190 will engage a ratchet gear tooth to prevent retrograde rotation of the ratchet gear. In the event more than two sets of driving pawls are employed it will be necessary to provide additional steps on the locking pawl 190 to allow for partial tooth rotational control of the ratchet gear.

Each of the upper and lower segments of the ratchet drive assembly 180 includes a driving arm 198 having a driving slot 200 formed therein. The connecting rod 166 includes a circular driving extremity 202 which is received within the driving slot 200 to provide a lost motion connection between the connecting rod 166 and the ratchet drive assembly 180. Upper and lower tension springs 204 are retained between posts 206 on the arm 198 and posts 208 on upper and lower extensions 210 of the connecting rod caps 168. The tension springs 204 bias the ratchet drive assembly in the clockwise direction opposing the connecting rods 166 and maintaining the extremity of the connecting rod in assembly with the driving recess 200. i

In the event a valve hand wheel or the like should be very difficult to turn upon initial breakloose operation thereof the motor operated wrench mechanism of this invention may be positioned relative to the hand wheel by relative angular adjustment of the motor operated wrench so that the ratchet drive mechanism will be rotated counterclockwise almost to its fully rotated position. The motor operated wrench mechanism will be energized in this position causing the motor and worm gear drive mechanism to reciprocate the connecting rod 166 with the circular extremity 202 within the driving recess 200. Under this condition the circular drive portion 202 of the connecting rod 166 will impact against the back portion of the slot 200 as the connecting rods reach the fully extended position thereof. This impacting movement will induce small increments of rotation to the ratchet drive mechanism 180 in a counterclockwise direction causing the driving

pawls

182 or 184 to drive the ratchet gear 174. Under these conditions extremely high torque forces are transmitted to the ratchet gear while only a minute rotation of the ratchet gear is achieved. A substantially frozen or extremely tight valve hand wheel may be broken loose in this manner and then normal successive rotative movements may be imparted to the ratchet gear 174 as counterclockwise movements of the ratchet drive mechanism become easier. The lost motion connection also allows initial starting of the motor so that momentum of the motor can be achieved prior to placing a load on the driving structure of the wrench mechanism thereby promoting long service free operating life of the wrench mechanism.

It will be evident from the foregoing that I have provided a novel motor operated wrench mechanism which utilizes a rotary motor for imparting successive rotative movements to an object to which the wrench mechanism is applied. The wrench mechanism includes a plurality of driving pawls which develop sufficient mechanical interconnection with a ratchet gear to prevent shearing of the teeth of the ratchet gear in the event a maximum load is applied by the ratchet gear drive mechanism. The ratchet gear drive mechanism is capable of achieving either full tooth rotational stroke or partial tooth rotational stroke to achieve varying increments of rotation of the ratchet gear in order to achieve positive rotation of the object to be rotated regardless of the tightness thereof. Further, my invention utilizes a lost motion connection between the motor driven connecting rods and the ratchet drive assembly in order to promote minute rotational control of the ratchet gear in the event the valve hand wheel or other object to be rotated may be substantially frozen or extremely difficult to turn. The lost motion connection of my invention also allows the electric or pneumatic drive motor to be brought up to momentum before a driving load is placed thereon. This feature effectively allows the use of motors which are of simple and reliable nature to drive the wrench mechanism. It is clearly apparent that because of the simple and unique construction of my invention that the invention will be low in manufacturing cost and reliable in use. It is obvious therefore that this invention effectively achieves all of the various objects noted hereinabove together with other advantages which are obvious from a description of the apparatus itself.

I claim:

1. A motor operated wrench mechanism for imparting successive rotative movements to an object to which said wrench mechanism is applied, said wrench mechanism comprising a wrench housing, a rotary motor carried by said housing, a pair of eccentrics journaled for rotation within said housing, said motor imparting rotation to said eccentric connecting rod means being reciprocated by said motor means and being received by each of said eccentrics, a ratchet drive mechanism journaled for rotatable oscillation within said wrench housing and including drive segments defining a central opening, said connecting rod means engaging said ratchet drive mechanism and imparting oscillational movement thereto, a ratchet gear journaled for rotation within said housing and being received within said central opening, a plurality of driving pawls carried by said ratchet gear, a locking pawl connected to said housing and engaging said ratchet gear to prevent retrograde rotation of said ratchet gear as said ratchet drive mechanism is oscillated, rotatable drive means carried by said ratchet gear and being adapted to drivingly engage the object to which the actuator mechanism is applied.

2. A motor driven actuator mechanism as set forth in claim 1, at least one of said driving pawls engaging the teeth of said ratchet gear upon rotation of said ratchet gear less than a full successive movement stroke, said locking pawl having a partial stroke stop shoulder thereon and preventing retrograde rotation of said ratchet gear subsequent to a partial stroke rotational movement thereof.

3. A motor driven actuator mechanism as set forth in claim 1, a worm rotatably driven by said motor, a worm gear journaled for rotation within said housing and having said eccentrics formed thereon.

4. A motor driven actuator mechanism as set forth in claim 1, means biasing said ratchet drive mechanism in the retrograde rotative direction, said connecting rod having a lost motion connection with said ratchet drive mechanism whereby the effective length of driving stroke of said connecting rod means may be varied by positioning said actuator mechanism rotatively relative to the object which is to be rotated to achieve slight successive rotational movements with extremely high torque output of said actuator mechanism.

5. A motor operated wrench for imparting successive rotative movements to an object to which the tool is applied, comprising a housing, a motor supported by said housing, said motor having a rotatable shaft, a worm gear mounted on said shaft, a worm wheel having an eccentric crankshaft defining an eccentric on either side of said worm gear, said worm wheel being operatively engaged by said worm gear, a ratchet drive assembly being journaled for rotation within said housing and defining a central opening, a ratchet gear being journaled for rotation within said housing and being received within said central opening a connecting rod having one end thereof engaging each of said eccentrics and the other end thereof being connected to said ratchet drive assembly, said ratchet gear having a female Spline formed therein, spring biased pawl means engaging the ratchet gear to prevent reverse rotation of said gear, said female spline being adpated to receive an adaptor tool having a splined shank at one end adapted to fit in the female spline and with lugs at the other end to fit over a hand wheel of a gate valve that is to be operated upon.