US3734459A

US3734459A - Handle and trigger construction

Info

Publication number: US3734459A
Application number: US00229774A
Authority: US
Inventors: W Sauerwein; R Meloni; H Walter
Original assignee: Black and Decker Manufacturing Co
Current assignee: Black and Decker Corp
Priority date: 1970-08-21
Filing date: 1972-02-28
Publication date: 1973-05-22
Anticipated expiration: 1990-05-22

Abstract

A portable tool including a housing having a rotary pneumatic motor disposed therein and coupled to a tool spindle. Compressed air is delivered to the motor by conduit means which includes passage means in a handle dependent from the housing. A throttle valve is disposed within the handle and is controlled by a trigger pivoted upon the handle. The trigger and handle are provided with novel adjustable stop means to limit trigger movement.

Description

United States Patent 1 Sauerwein et al.

HANDLE AND TRIGGER CONSTRUCTION Inventors: William D. Sauerwein, .loppa; Robert A. Meloni, Baltimore; Harvey J. Walter, Joppatown, all of Md.

Assignee: The Black and Decker Manufactur ing Company, Towson, Md.

Filed: Feb. 28, 1972 Appl. No.: 229,774

Related US. Application Data Division of Ser. No. 65,954, Aug. 21, 1970, Pat. No. 3,666,027.

U.S. Cl. ..251/285, 151/25 C Int. Cl ..Fl6k 51/00 Field of Search ..251/285; 151/25 C;

[111 3,734,459 1 May 22,1973

[56] References Cited UNITED STATES PATENTS 223,326 1/1880 Emerton ..251/285 X 578,603 3/1897 Hill ..25l/285 X 2,898,893 8/1959 Rohrer et al ..173/l70 X 3,037,740 6/1962 Sheps et al ..251/285 X 3,070,125 12/1962 Gulley ..251/285 X 3,429,556 2/1969 Kustwin ..251/285 Primary ExaminerHenry T. Klinksiek Attorney-Leonard Bloom, Joseph R. Slotnik and Edward D. Murphy [571 ABSTRACT A portable tool including a housing having a rotary pneumatic motor disposed therein and coupled to a tool spindle. Compressed air is delivered to the motor by conduit means which includes passage means in a handle dependent from the housing. A throttle valve is disposed within the handle and is controlled by a trigger pivoted upon the handle. The trigger and handle are provided with novel adjustable stop means to limit trigger movement.

4 Claims, 4 Drawing Figures HANDLE AND TRIGGER CONSTRUCTION This is a division of application Ser. No. 65,954, filed Aug. 21, 1970, now U.S. Pat. No. 3,666,027.

SUMMARY OF THE INVENTION The present invention is directed to a novel adjustable trigger construction for a variable speed, portable tool or the like. The trigger is pivoted upon, for example, a tool handle to operate a throttle valve, electrical or electronic speed control, of the like, and includes adjustable means integrated therewith and cooperable with means rigid with the handle to vary the extent to which the trigger can pivot and therefore the speed of the tool. The adjustable means is adapted for easy, manual adjustment, includes means for retaining it in incrementally adjusted positions, and is constructed so that the tool will operate even if the adjustable means is removed or fails. Furthermore, the adjustable means is safe, compact and convenient, involves a minimum of parts and expense, and presents a neat and aesthetically pleasing appearance.

Main objects of the present invention are to provide a novel pivotal, adjustable trigger construction for a variable speed power tool or the like, which construction is compact and is integrated with the trigger and its mount, and is quickly and easily manually adjustable while being retained in incrementally adjusted positions.

Further important objects are to provide a novel trigger construction of the above character which will function in the absence of or upon failure of the adjustment construction, which includes a minimum of separate parts, and wherein most of these parts are concealed or out of the way thereby presenting a neat and aesthetically pleasing appearance.

Additional important objects are to provide a novel trigger construction of the above character which is relatively inexpensive to manufacture, rugged in construction, and safe and reliable in use.

Other objects and advantages will become more apparent from a consideration of the detailed description to follow taken in conjunction with the drawings annexed thereto.

FIG. 1 is a sectional view illustrating a portable pneumatic tool embodying the present invention and showing the trigger construction in one adjusted position;

FIG. 2 is a view of a portion of FIG. 1 and showing the trigger construction in another adjusted position;

FIG. 3 is an enlarged sectional view of the structure of FIG. 1 taken along the line 3-3 thereof; and

FIG. 4 is an enlarged sectional view of FIG. 2 taken along the line 4-4 thereof.

BROAD STATEMENT OF THE INVENTION Broadly described, the present invention relates to a throttle valve and actuator comprising a body having passage means therethrough, a normally closed throttle valve in said passage means and adapted to control the flow of pressurized fluid therethrough, means for opening said throttle valve including an actuator pivoted on actuator inner portion and said body including cooperable abutment means rigid therewith and allowing only limited pivotal movement of said actuator in both said directions, said abutment means on said actuator being adjustable relative to said abutment means on said body by means on said actuator inner portion to vary the extent of allowed pivotal movement of said actuator in at least one direction.

DETAILED DESCRIPTION Referring now more specifically to the drawings, the present invention is seem embodied in a pneumatic impact wrench generally indicated at 11 in FIG. 1. However, it is to be understood that this tool is for purposes of illustration only.

With this in mind, the wrench 11 includes a housing comprising a motor housing 13, a clutch housing 15, a rear cover 16, and a handle 17 secured together in suitable fashion. A rotary pneumatic motor 18 is disposed in the motor housing 13 and includes a rotor 19 having fore and aft stub shafts 21, 23 rotatably supported by

bearings

25, 27 in

end plates

29, 31. The rotor 19 carries a plurality of radially disposed vanes 33 adapted to slidably engage the inner wall of a cylinder liner 35 and trapped endwise between the

end plates

29, 31.

The stub shaft 21 is splined to a cam driver 37 which is coupled to a dog 39. A clutch pin 41 connects the dog 39 and a clutch body 43, and the dog 39 is adapted to engage a jaw 45 formed on a clutch shank 46. The forward end of the shank 46 forms a tool spindle 47 to which a suitable tool bit, e.g., a wrench socket, can be fixed and is supported within the housing by a bushing 49. The dog 39 is adapted to engage and constantly drive the shank 46 at low torque levels and intermittently engage or impact against the shank 46 at higher torque levels.

Pressurized air is delivered to the tool 11 from a source through a conduit (not shown) fastened to a coupling 51 threaded into a valve cavity 53 in the handle 17. A valve member 57 is positioned in the cavity 53 and is normally biased by a compression spring 59 into seated relation with a valve ring 55. The valve member 47 has a stem 61 extending through an opening 63 in the ring 55 and is slidably received in an opening 65 in the handle 17.

When the valve 57 is unseated from the ring 55, pressurized air is delivered to passage 67 and port 69 in the handle 17 and a reversing valve sleeve 71, respectively. In the position of the parts shown in FIG. 1, this air then passes out through a port 73 in sleeve 71, through pas sages (not shown) in the housing 13 and rear cover 16, and then to the motor 18. Air is exhausted from the motor 18 through

ports

75, 77 in the liner 35,

ports

79, 81 in housing 18 and sleeve 71, and out to atmosphere.

When it is desired to reverse operation of the motor, a spool 83 positioned in the sleeve 71 is pushed rearwardly or toward the right, as seen in FIG. 1. Now, pressurized fluid flows from passage 67 and port 69 out through port 85, and to motor 18 through other passages (not shown) in the housing 13 and rear cover 16. Air is now exhausted from motor 18 through

ports

75, 77

ports

87, 89 in housing 13 and sleeve 71, and then to atmosphere. Desirably, detent means (not shown) retains the spool 83 in these positions.

A trigger, generally indicated at 91 in FIGS. 1 and 2, is provided on the handle 17 for actuation of the throttle valve. As shown, the trigger includes a body 93 set partially within a pocket 94 in the handle 17 and pivoted at its lower end thereon by a pin 95. The body 93 has an inner portion which is inaccessible to the operators fingers during normal tool operation and formed with a recess 97 which defines first and second abutment surfaces 99, 101. A projection 103 formed integral with the handle 17 and located within the: pocket 94 is receivable in the recess 97 and defines first and

second abutment surfaces

105, 107 adapted to engage the abutment surfaces 99, 101 and limit pivotal movement of the trigger body 93 in both directions.

The trigger body 93 has a surface 109 adapted to engage the end of the valve stem 61. The body 93 also has an outer portion including a concavely shaped upper portion 111 which accommodates one or more fingers of the operator when his hand is on the handle 17. Thus, with his hand so positioned, the operator can easily pivot the trigger body 93 in a clockwise direction, as seen in FIGS. 1 and 2, whereby to move the valve stem 61 downwardly and unseat the valve body 57 from the ring 55. This, in turn, allows pressurized air to pass into the motor 13 and rotates the rotor 19 and the shank 46 and spindle 47. Clockwise pivotal movement of the trigger body 93 is limited by engagement of the surfaces 99, 105 which, in turn, limits the extent to which the valve 57 can move away from the ring 55. When the trigger body 93 is released, the spring 59 moves the valve body 57 back into seated relationship with the ring 55 (to shut off the tool) and the valve stem 61 pivots the trigger body 93 in a counterclockwise direction. Engagement between

surfaces

101, 107 limits pivotal movement of the body 93 in this direction and prevents the body 93 from coming completely out of the pocket 94.

It is desirable that means be provided to adjust the throttling action of the valve body 57. To this end, the effective position of the abutment surface 99 relative to the abutment surface 105 is adjusted so that the extent to which the trigger body 93 can pivot in a clockwise direction is correspondingly adjusted. This is achieved by a screw 113 which is threaded into the body 93 and having an end 115 adapted to extend beyond the surface 99.

FIG. 1 illustrates the screw 113 withdrawn so that its surface 115 does not protrude from the surface 99. In this position, full pivotal movement of the trigger 93 is allowed and the valve 57 can open fully. FIG. 2, on the other hand, shows the screw 113 adjusted so that its surface 115 extends beyond the surface 99. Now, the screw surface 115 engages the surface 105 before surface 99 does and correspondingly limits allowed pivotal movement of the trigger 93 and the extent to which the valve 57 can open.

The screw 113 is provided with a knurled head 117 which is outside the trigger body 93 but is behind the finger portion 111. This allows the operator to easily adjust the screw 113 while partially concealing it and rendering it inaccessible during tool operation. However, to resist inadvertent or accidental movement of the screw 113, a detent comprising a ball 119 and spring 121, is set into a pocket 123 in the trigger body 93, and cooperatively engages the knurled head 1 17, as seen in the drawings. It will be appreciated, however, the screw 113 can be finger turned against the holding force of the ball 119 and spring 121.

It will be appreciated that the handle 17 (which generally is cast metal) simply is formed with the pocket 94 and the integral projection 103. The trigger body 93, on the other hand, is a relatively small and replaceable element and can be molded using a suitable plastic. The screw 113 is threaded directly into the body 93 (rather than the handle 17) and the ball and

spring

119, 121, also located therein so that this trigger assembly can be packaged and assembled to handle 17 as a separate unit. Thus, this trigger construction described achieves maximum efficiency, convenience, and reliability, with a minimum of cost and, in addition, by the concealed ball, detent and screw, presents a neat and aestheticaliy pleasing appearance devoid of unsightly or unattractive parts.

By the foregoing there has been disclosed a novel trigger construction calculated to fulfill the inventive objects set forth, and while a preferred embodiment of the invention has been illustrated and described in detail, various additions, substitutions, modifications, and omissions may be made thereto without departing from the spirit of the invention.

What is claimed is:

1. A throttle valve and actuator comprising a body having passage means therethrough, a normally closed throttle valve in said passage means and adapted to control the flow of pressurized fluid therethrough, means for opening said throttle valve including a actuator pivoted on said body for movement toward and away from said body and operatively engageable with said valve, said actuator having an outer portion adapted for finger engagement by an operator during normal tool operation and an inner portion generally inaccessible to the fingers of an operator during normal tool operation; said actuator inner portion and said body including cooperable abutment means rigid therewith and allowing only limited pivotal movement of said actuator in both said directions, said abutment means on said actuator being adjustable relative to said abutment means on said body by means on said actuator inner portion to vary the extent of allowed pivotal movement of said actuator in at least one direction.

2. A construction as defined in claim 1 wherein said abutment means on said actuator includes a screw threadedly adjustable toward and away from said abutment means on said body.

3. A construction as defined in claim 2 wherein said screw is accessibly positioned on said actuator for manual adjustment but is disposed on the side of said actuator nearest said body, whereby to partially conceal said screw.

4. A construction as defined in claim 2 which includes detent means on said actuator engageable with said screw, whereby to releasably retain said screw in incrementally adjusted positions.

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