US2395541A - Wrench - Google Patents

Description

Feb. 26, 1946. w. c. FAGEL.

WRENCH Filed July 1o, 1944 x gg Inventor: Walter C. Fagel, b 4' 9 I-Is /torn 9.

Patented Feb. 26, 1946 UNITED STATES PATENT OFFICE WRENCH Walter C. Fagel, Schenectady, N. Y. Application July 10, 1944, Serial No. 544,233 2 claims. (o1. zs-zisl My invention relates to wrenches and in particular to a wrench for pulling and positioning a piston in an engine cylinder to facilitate securing a connecting rod to the crankshaft of the engine.

An object of my invention is to provide an improved wrench construction.

Another object of my invention is to provide an improved piston connecting rod assembly wrench.

' Further objects and advantages of my invention will become apparent and my invention will be better understood from the following description referring to the accompanying drawing, and the features of novelty which characterize my invention will be pointed out with particularity in the claims annexed to and forming part of this specification.

In the drawing, Fig. 1 isa side elevational view of an embodiment of my improved wrench illustrating its use for pulling and positioning a piston and connecting rod inan engine cylinder; Fig. 2 is a partial sectional View taken longitudinally of the Wrench shown in Fig. 1; Fig. 3 is a sectional view taken along line 3-3 of Fig. 2; and Fig. 4 is an end view of the upper end of the wrench shown in Figs. 1 and 2, partly in section, taken along line 4--4 of Fig. 3.

Referring to the drawing, I have shown an embodiment of my improved piston connecting rod assembly Wrench construction in which the wrench is provided with a relatively long tubular shank member I having a hand-grip portion 2 which may be knurled to provide an eicient gripping surface adjacent an end of the shank member. A supporting head member 3 is secured to the opposite end of the shank in any suitable manner, as -by a press fit of a head portion II in the end of the shank. This head member is arranged to extend angularly and preferably substantially at right angles to the shank member to provide a support for clamping jaws at ar slight distance from the axis of the shank member I. The wrench is provided with gripping elements which are formed as a pair of jaws 5 arranged in the head 3 and have grooved engaging faces 6 which are adapted to be used to provide aclamping engagement with a piston connecting rod 'I, as shown in Fig. 1. In many instances, it is very difcult to align a piston properly in a cylinder such that the bearing o-f the piston connecting rod is in correct alignment with the crankshaft of the engine. In order to pull the piston into the cylinder and to obtain this alignment, I arrange the clamping jaws 5 adjacent one end of the relatively long shank member I and provide for the operation of these jaws from the other end of the shank member so that the piston connecting rod may be prop'- erly positioned without having to reach far up into the engine block. This also provides the necessary leverage for turning the piston slightly p if this is necessary to provide the required alignment of parts. This construction includes a pivotal support for the pair of jaws 5 on the head 3 formed by a pair of pivot pins 8, each provided with a head 9 and a threaded end Il) opposite the head 9 which threadedly engages a complementary opening formed in the head 3.. These pins 8 extend through a cover or protecting housing element II which is secured over the jaws 5 and to the head 3 by the pins 8 and by a screw I2 which extends through the rear portion of the cover II and threadedly engages a complementary opening in the head 3. The jaws 5 are biased to an open position by a substantially U-shaped leaf spring I3 arranged in engagement with the outer side of fingers I4 formed integral with the jaws 5 and extending in a direction away from the jaws from the pivotal supporting means. This spring I3 resiliently biases the jaw fingers I4 towards each other and thereby biases apart the jaw faces 6.

In order to operate the jaws 5 of the wrench, the underside of the fingers I4 are formed with oppositely tapered cam surfaces I5 which extend over the tubular shank member I and are adapted to be biased apart by a complementary tapered cam I6 formed as the end of an operating rod I'I which is arranged within the tubular shank member VI. clamping of the wrench onto a piston rod as previously explained, the head 3 and jaws 5 are arranged adjacent one end of the shank member I and the operating rod I'I is arranged to W be operable from the opposite end of the shank member I. This feature is provided by forming an internally threaded portion I8 on the inside of the tubular shank member I and providing a complementary threaded portion I9 on the operating rod I'I arranged in threaded engagement with the shank portion I8. A knurled operating knob element 20 is fastened to the end of the operating rod I'I opposite the cam end I6 to provide for readily turning the operating rod I1 to screw the rod through the threaded shank portion I8 and thereby to move the rod I1 toward and away from the jaw nger cam surfaces I5 for biasing apart the fingers I4 and closing or opening the jaw faces relative to each In order to facilitate the other. The particular location of the threaded portion of the shank and the operating rod and the particular construction of the gripping surfaces of the shank I and of the knob 20 can obviously be formed in a number of different suitable ways. In the preferred embodiment of my construction, as shown in Fig. 2, the shank engaging dportion 4 of the head 3 also provides a bearing surface for guiding the cam end'of the operating rod I'I, and the knob 20 is formed with a sealing portion 2l which is adapted to provide a closure at the adjacent end of the shank member I to provide against the entrance of foreign substances into the shank.

As shown in Fig. 3, the operating rod II may be screwed outwardly from the shank member I so that its cam surface I6 is out of engagement with the cam surfaces I5 of the jaw fingers I4, such that the leaf spring I3-biases the jaw faces 6 away from each other to provide for placing them about a piston connecting rod flange o1' any other appropriate member. The jaws 5 may then be biased towards each other to engage the connecting rod by screwing the operating rod Il into the shank I, such that the cam end I6 of the rod engages the cam surfaces I5 of the jaw fingers I4 and biases apart the jaw fingers against the resisting action of the spring I3 and closes the jaws 5 about the element which is to be clamped. In this manner, a piston connecting rod or any other suitable element may be firmly gripped by the wrench at a considerable distance from the hand of the operator, and the wrench will provide a secure grip on the element which will enable pulling and positioning of the element and any other associated member, such as a piston, into its proper position relative to another element, such as an engine crankshaft. This will greatly facilitate the assembly of engines and other mechanical elements to which access may be found to be rather difficult and will also save considerable time and effort in properly positioning such elements relative to each other.

While I have illustrated and described a particular embodiment of my invention, modifications thereof will ccur to those skilled in the art. I desire it to be understood, therefore, that my invention is not to be limited to the particular arrangement disclosed, and I intend in the appended claims to cover all modifications which do not depart from the spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. AA wrench for gripping dimcultly accessible parts, said wrench including a tubular shank member, a jaw supporting head member formed of two parts and extending at substantially right angles to said shank member, said head member forming a closure over an end of said shank, one of said parts forming the bottom of said head and being secured to the adjacent end of said shank, the other of said head parts forming a top and back for said head and being connected to said bottom part and spaced apart therefrom providing a jaw guide, means including a pair of jaws arranged in said head member and having faces for clamping engagement with an object to be moved, means for pivotally supporting said jaws on said head, operating ngers on said jaws extending in the direction away from said faces from said pivotal supporting means, means including a spring arranged between said top and bottom of said head adjacent said back of said head and in engagement with said operatingflngers for resiliently biasing said jaw faces apart, oppositely tapered cam surfaces on the underside of said jaw fingers, an internally threaded portion in said tubular shank of smaller diameter than the internal diameter of the remainder of said shank and spaced longitudinally from the end of said shank opposite from said head, means including an operating rod in said tubular shank arranged in threaded engagement with said threaded portion of said shank providing for movement of said rod toward and away from said jaw finger cam surfaces for closing and opening said jaw faces toward each other, and means including a sealing member arranged in engagement with said rod for providing a seal at the end of said shank opposite said head.

2. A piston connecting rod assembly wrench including a tubular shankmember, a jaw supporting head member extending substantially at right angles to said shank member forming a closure over an end of said shank, said head having a bottom secured to the adjacent end of said shank and a top spaced apart from said bottom providing a jaw guide space therebetween with a back'closure extending between said top and bottom forming a. spring guard at the back of said head, means including a pair of jaws arranged in said head member and having grooved faces for clamping engagement with an object to be moved, means including pivot pins for pivotally supporting said jaws on said head, operating fingers on said jaws extending in the direction away from said faces from said pivotal supporting means, means including a spring arranged within said jaw guide space and adjacent said back closure of said -head in engagement with the outer sides of said fingers for resiliently biasing said jaw fingers towards each other and said jaw faces apart, oppositely tapered cam surfaces on the underside of said jaw fingers extending over said tubular shank, an internallythreaded part spaced longitudinally of said shank between said jaw finger cam surfaces and the opposite end of said shank and having a smaller diameter than the unthreaded internal diameter of said tubular shank, means including an operating rod having a tapered cam operating end in said tubular shank and having a threaded portion arranged in threaded engagement with said threaded part providing for movement of said rod toward and away from saidjaw finger cam surfaces for biasing apart said fingers and closing and opening said jaw faces toward each other, and means on said operating ,rod 'at the end thereof away from said tapered cam operating end providing a seal with the end of said shank away from saidhead.

WALTER C. FAGEL.

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