US2911822A - Portable tool analyzer - Google Patents

Description

Nov. 10, 1959 A. FRAZIER ETAL ZORTABLE TOOL ANALYZER Filed Dec. 26, 1956 RIVE) INVENTOR. GEORGE A. FRAZ/El? 8 RILEY A. SEXTON BY PORTABLE TOOL ANALYZER George A. Frazier, Fort Worth, and Riley A. Sexton,

Arlington, Tex., assign'ors to General Dynamics Corporation, San Diego, Calif., a corporation of Delaware Application December 26, 1956, Serial No. 630,525

3 Claims. (Cl. 73-116) This invention relates to portable tool analyzers and more particularly to a portable pneumatic hand tool analyzer which may be moved to where the tools are in use for testing.

Heretofore when a pneumatic hand tool did not seem to function properly the operator returned the tool for servicing. The only standards set by the manufacturer on the performance of his tool were revolutions per minute and air consumption of the tool. If the tool did not meet these standards the repairman examined it, took it apart, and replaced parts that appeared to be worn or damaged. When it was put back together again the repairman had no way of determining whether its performance would be satisfactory under normal load conditions. The tool may pass the revolutions per minute and air consumption test and still not have satisfactory performance or be adequately serviced. A tool that checks up to standard in the tool service area still may not give satisfactory performance on the job. Sometimes the tool trouble may be traced to low air pressure due to defective air valves, Worn fittings, undersize hose or other obstructions in the air line. Without pro-per testing equipment and performance standards there could be no preventive maintenance procedures. Costly repairs have resulted through failure to detect neglect or trouble in advance. Lack of proper bearing lubrication, binding spindles or other factors producing undue friction reduce the normally long life of the precision tools, which otherwise might have been avoided with proper testing and maintenance procedures.

These and other problems are now overcome by this invention which consists of a mobile test cart equipped with testing devices for checking the performance of rotary-type hand tools, air lines and fittings. It has been determined that for a true test of a tools performance it is necessary to know the air consumption of the tool, the air pressure in the air line, the revolutions per minute of the tool without load, and the horsepower under load. Suitable instruments for determining these factors are provided as well as an oil spray device for lubricating the tool being checked.

It is therefore an object of this invention to provide for a mobile tool analyzer.

Another object is the provision of a mobile tool analyzer which may be used to check the tool at its use location.

Another object is the provision of a pneumatic tool analyzer which also checks the air supply to the tool.

Another object is the provision of a pneumatic tool analyzer which controls the air supply while obtaining performance data.

Still another object is the provision of a pneumatic tool analyzer which will test a tools performance.

Still another object is the provision of a pneumatic tool analyzer which checks the available air pressure, the air consumption of the tool, the rpm. of the tool without load, and the horsepower of the tool under load.

Other objects and features of the present invention will be readily apparent to those skilled in the art from the following specification and appended drawings wherein is illustrated a preferred form of the invention, and in which:

Figure l is a front View of the analyzer; and

Figure 2 is a rear view with the rear doors removed.

Referring now to Figure 1 there is shown the analyzer cart 11 mounted for movement on rollers 12 and swivel casters 13. On the top of the cabinet are two Prony brakes 16 and .17, one for measuring inch pounds of torque and the other for measuring foot pounds. Suitable linkage and weights are mounted within the cabinet for actuating the torque indicators 18 and 19 mounted on instrument panel 21 at the rear of the top of the cabinet. An air flow meter 22, line air pressure gauge 23, tachometer 24 and volume tank pressure gauge 26 are also mounted on the instrument panel 21. Separate switches 25 and 25A permit independent reading from the tachometer 24 of spindle speed of either of the brakes 16 and 17.

Referring now to Figure 2, wherein is shown the rear view with the doors removed, the air hose 27 from a remote air supply (not shown) is connected to an air filter 28 which removes any foreign matter from air passing through the line. The air pressure is then regulated by regulator 29 to the desired pressure as shown by the regulated air pressure gauge 23. The air consumption is then measured directly by air flow meter 22 in cubic feet per minute. From the air flow meter the air passes into a volume tank 31 which maintains the air at a constant air pressure. Connected to the volume tank is a lubricator 30 for spraying a fine mist of oil through each tool being checked. Air hose 32 is for connection of an air tool to the controlled air supply. The rotary shaft of the air tool (not shown) is operably connected to drive spindle 33 on Prony brake 17. The spindle turns the tachometer generator 35 which is connected by switch 25 to the tachometer 24. If a smaller tool is being checked Prony brake 16 is used, and switch 25A connects tachometer generator 35A to the tachometer for reading.

Although other types of instruments and components may be used, the following were found to be satisfactory in the preferred embodiment: Airline filter #65B and Airline Lubricator #65F from Keller Tool Company, C. A. Norgren type 242 regulator, Airflow meter Tool 0 Meter No. TO-40 from New Jersey Meter Company, Westinghouse Tachometer type NC-37, a 0100 p.s.i. volume tank pressure gauge and Chantillon 30 torque in- 'dicators.

When the rotary type hand tool to be checked has been set in the Prony brake 16 or 17, and connected to the air supply through the flexible hose 32, the tool is ready for testing. Since most tools are designed for operation at p.s.i., the air pressure is set to that amount. Since the manufacturer specifies an r.p.1n. for each tool, the pressure is released from the Prony brake to get the tool started and a free speed reading. The r.p.m. without load is now checked. A load is now applied by rotating knob 34, tightening arms 36 against wheel 37. This torque is read from torque indicator 18 or 19 to get the horsepower under load. Three simultaneous readings are obtained, the rpm. from the tachometer 24, the torque from the spring scale reading, and air consumption from the air flow meter. The air pressure gauge 26 is checked to insure the proper pressure regulation. The horsepower may be computed from the r.p.m. and torque or read from a chart having these relationships. It should be noted that a fin spray of oil mist from lubricator 3t lubricates the tool while the test is being performed. Performance of electrical rotary type hand tools may also be tested with the analyzer. The r.p.m. without load, and horsepower under load may be checked in the same manner as pneumatic tools.

Because manufacturers do not furnish data on tool performance other than air consumption and r.p.m., new

standards of performance must be made for each of the large number of hand tools by types and brands. This may be done by testing each new tool before it has been used and recording the information on a card forready reference. When a sufficient number of tools of a particular type (twenty is considered an adequate number) have been tested, a standard of performance, with upper and lower limits, may be devised for that too]. Thus, by comparing data from the tool under test with the established standard of performance, the serviceability of the tool may be checked. The results may be recorded on individual tool maintenance cards for use by the repairman in overhauling the tool. Moreover, the standards established from testing new tools and the performance of tools in use serve as a guide to purchasing new tools.

No longer need the claims or reputation of the manufacturer be relied upon since actual tool performance data is now available. By testing and lubricating regularly minor faults may be detected and remedied before they become serious. Since expensive gears and bearings are often affected by even one damaged or worn part, being able to detect neglect and future trouble in advance can save costly repairs. Historical data of repair costs and performance taken from individual tool maintenance records may be used to provide justification of new tool purchases. Frequently tools have been overhauled when it would have been more practical and inexpensive to replace the tool.

Many benefits are to be realized from the use of the tool analyzer comprising this invention. Among them are:

(1) Increased production resulting from increase in the efficiency of the tools,

(2) Lost time reduction because of better tool service and fewer in use breakdowns,

(3) Extended life of tools due to preventative maintenance measures, and

(4) Reduced cost in tool repairs.

While certain preferred embodiments of the invention have been specifically disclosed, it is understood that the invention is not limited thereto as many variations will be readily apparent to those skilled in the art and the invention is to be given its broadest possible interpretation within the terms of the following claims:

What we claim is:

1. A mobile tool analyzer for checking pneumatic rotary tools at their place of use comprising a movable test cart, an instrument panel on said cart, an air conduction path including an air filter mounted on said panel and adapted for connection to a remote source of air pressure, valve means for controlling the air supply from said source, means connected to said path for measuring the rate of air passage therethrough, a volume air supply tank for maintaining air pressure at a constant predetermined value, means for injecting an oil spray mist into said path, flexible hose means for connecting a pneumatic tool to said spray means, counting means for indicating the r.p.m. of said tool comprising a rotatable spindle adapted to be operably connected to said tool and rotated thereby, an electrical generator means connected to and driven by said spindle for generating an electrical output indicative of the speed of rotation of said spindle, and readout means mounted on said panel and connected to said generator means for indicating the r.p.m. of said spindle corresponding to the electrical output of said generating means, friction means for applying a load to said tool comprising a wheel rotatably mounted to turn with said spindle, means frictionally engaging said wheel for retarding the rotation of said spindle and producing a torque thereon, and indicia means on said panel and operatively connected to said friction means for indicating the torque on said spindle.

2. A mobile tool analyzer for checking pneumatic rotary tools at their place of use comprising a movable test cart, an instrument panel on said cart, an air conduction path including an air filter mounted on said panel and adapted for connection to a remote source of air pressure, valve means for controlling the air supply from said source, means connected to said path for measuring the rate of air passage therethrough, a volume air supply tank for maintaining air pressure at a constant predetermined value, flexible hose means for connecting a pneumatic tool to said air path, counting means for indicating the r.p.m. of said tool comprising a rotatable spindle mounted on said cart, adapted to be operably connected to said tool and rotated thereby, an electrical generator means connected to and driven by said spindle for generating an electrical output indicative of the speed of rotation of said spindle, and readout means mounted on said panel and connected to said generator means for indicating the r.p.m. of said spindle corresponding to the electrical output of said generating means, friction means for applying a load to said tool comprising a wheel rotatably mounted to turn with said spindle, means frictionally engaging said wheel for retarding the rotation of said spindle and producing a torque thereon, and indicia means on said panel and operatively connected to said friction means for indicating the torque on said spindle.

3. A mobile tool analyzer for checking pneumatic rotary tools at their place of use comprising a movable test cart, an instrument panel on said cart, an air conduction path including an air filter mounted on said panel and adapted for connection to a remote source of air pressure, valve means for controlling the air supply from said source, means connected to said path for measuring the rate of air passage therethrough, a volume air supply tank for maintaining air pressure at a constant predetermined value, fiexible hose means for connecting a pneumatic tool to said air path, a pair of rotatable spindles each adapted to be operably connected to said tool and rotated thereby, a pair of electrical generator means each connected to and driven by one of said spindles for generating an electrical output indicative of the speed of retation of each of said spindles, and a single readout means mounted on said panel and alternately connected to each of said generator means for indicating the r.p.m. of its associated spindle corresponding to the electrical output of said generating means associated therewith, friction means for applying a load to said tool comprising a pair of wheels each rotatably mounted to turn with one of said spindles, means frietionally engaging said spindles and producing a torque thereon, and indicia means on said panel and operatively connected to said friction means for indicating the torque on said spindles.

References Cited in the file of this patent UNITED STATES PATENTS 2,004,950 Jenkins June 18, 1935 2,310,974 Lumm Feb. 16, 1943 2,366,889 Westberg et a1. Jan. 9, 1945

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