US2927731A

US2927731A - Transit mixer revolution counter

Info

Publication number: US2927731A
Application number: US476377A
Authority: US
Inventors: Rassele E Swarthout
Original assignee: CHALLENGE Manufacturing CO
Current assignee: CHALLENGE Manufacturing CO
Priority date: 1954-12-20
Filing date: 1954-12-20
Publication date: 1960-03-08
Anticipated expiration: 1977-03-08

Description

Maid! 1960 R. E. SWARTHOUT 2,927,731

TRANSIT MIXER REVOLUTION COUNTER Filed Dec. 20, 1954 INVENTOR. R4 55545 E 5W4R7H0l/7 ATTORNEY Unitcd States Patent TRANSIT MIXER REVOLUTION COUNTER Rassele E. Swarthout, Santa Monica, Calif., assignor to Challenge Manufacturing Co'., Los Angeles, Calif., a corporation of California Application December 20, 1954, Serial No. 476,377

3 Claims-1C1. 235-91) This invention relates to counting and recording the revolutions and speed of revolutions of the drum-of a truck type. or transit concrete mixer. Transit mixers are used to transport concrete "already mixed, as a mixer en transit to a point of use, or as a mixer at the point of use. Whether used in one way or another, the operation will be benefited by counting the number and speed of revolutions of the drums of such transit mixers, to give uniformity of quality of the end product and also remove guesswork from the operation. Thus, errors of judgment are, in a large measure, obviated and operator inexperience removed from affecting the quality of mix. The foregoing is particularly true where the mix must be performed according to specification re quirements and affords an inspector or supervisor a sure and dependable means to ascertain that such requirements are being honored.

Since over-mixing of concrete as Well as under-mixing is not desirable, homogeneity of mix being lacking under both such faulty operations, it is an object of the present invention to provide novel and improved means for readily determining the number and the speed of the revolutions of the drum of a transit mixer to afford the benefits as well as obviate the faults hereinbefore mentioned.

Counting and recording the number of revolutions of each separate mix, being desired, it is another object of the invention to provide means adapted to be re-set to zero so that such separate counting may be effected.

A further object of the invention is to accumulate the different counts of the revolutions of the mixer drum, thereby providing a means to determine service requirements of the mixer appartus and useful life expectancy.

The invention also has for its objects to provide such means that are positive in operation, convenient in use, easily installed in a working position and easily disconnected therefrom, economical of manufacture, relatively simple, and of general superiority and serviceability.

The invention also comprises novel details of construction and novel combinations and arrangements of parts, which will more fully appear in the course of the following description. However, the drawing merely shows and the following description merely describes, one embodiment of the present invention, which is given by way of illustration or example only.

In the drawing, like reference characters designate similar parts in the several views.

Fig. 1 is a top plan view of a generally conventional transit type mixer provided with the present drum-revolution counting means.

Fig. 2 is an enlarged side elevational view of said counting means, the support means therefor being shown in cross-section.

Fig. 3 is a face view of the visual indicator of said counting means.

The conventional truck type or transit mixer that is illustrated in Fig. 1 is shown as provided with a wheelmounted chassis 5 on the forward portion of which is "ice provided the usual cab and motive means 6 and the rearwardportion mounting a mixing drum 7. Said drum is here shown as being rotated by an engine or motor 8 provided with a variable speed transmission 9, through the medium of a speed reducer 10, operatively connected to transmission 9 by a drive shaft 11 and a chain. and sprocket drive 12 operatively connecting said reducer 10 and the drum 7. The drum 7 is shown as horizontally disposed, although in practice the same is at an angle with the open rear end elevated with respect to the opposite end.

The present drum-revolution counting and recording,

means 13 is shown as being driven from the transmission 9. This may be varied, however, since said means 13 may be driven from the speed reducer 10 or from any part of the means that may be used for rotating drum 7.

The means 13 that is illustrated comprises, generally, a drive connection 14 deriving its rotation from transmission 9 or other means in the driving train of the drum 7, a tachometer type of unit 15 driven by connection 14, and a gear box 16 interposed between said connection and unit to impart a desired speed ratio between the drive of'the transmission and that of the tachometer.

The drive connection 14 may comprise a flexible shaft 17 enclosed in a sheath 18 and extends, in the form shown, from any rotating member in transmission 9 to gear box 16.

Said gear box is provided for the purpose of causing the connection to provide a proper speed ratio drive to tachometer 15. It will be noted that the drive between transmission 9 and drum 7 not only goes through gear box 10 but also includes a chain and sprocket drive 12 that further reduces speed. Thus, the speed of shaft 11 is substantially greater than the speed of rotation of the drum. Since the tachometer counts drum revolutions, it is necessary to drive the same at a speed related to the speed imparted to the drum. Hence, the gear box 16 in the drive to the tachometer.

Said tachometer 15 may follow speedometer design in that the same is provided with a pointer 19 that sweeps the dial 20 according to the input speed from gear box 16, and is also provided with an accumulating counter 21 and a counter 22 that is re-settable to zero as by a knob 23. By providing said dial with a scale 24 that can be read as drum revolution speed, visual inspection of the dial will advise of three things: one, the speed at which the drum 7 is rotating (from zero to 20 revolutions per minute); two, the number of revolutions the drum has made since the counter 22 had been re-set to zero (241.6

011 the drawing); and, three, the total number of revolutions that the drum had made during the life of the mixer (28,761 on the drawing).

Thus, the mechanical condition of the mixer, as refiected by use, is shown by counter 21; the number of revolutions of the current mix by counter 22; and the speed of the mix by pointer 19- and scale 24. Therefore, it is a simple matter to set the drive for the drum to give a desired rotational speed of the drum so that agitation, mixing or charging may be effected and to determine whether a mix is properly completed.

Since the transmission 9 is usually of the reversing type so that drum 7 may be reversed when such is desired, the means 25 is provided for de-clutching the tachometer from gear box 16 during such reversal. Instead of such a control, a slip clutch may be interposed between the gear box and the tachometer.

While the foregoing has illustrated and described what is now contemplated to be the best mode of carrying out the invention, the construction is, of course, subject to modification without departing from the spirit and scope of the invention. It is, therefore, not desired to restrict the invention to the particular form of construction illustrated and described, but to cover all modifications that may fall within the scope of the appended claims.

Having thus described the invention, what is claimed and desired to'be secured by Letters Patent is:

1. In combination with a truck-mounted cement mixer having a rotating drum and a drive means for said drum, atachometer to count revolutions and show speed of revolutions of the drum, drive means interconnecting the tachometer and the drum, and a slip clutch interposed in the drive means for the tachometer.

2. In combination with a truck-mounted cement mixer having a rotating drum and a drive means for said drum, a tachometer to count revolutions and show speed of revolutions of the drum, drive means interconnecting the tachometer and the drive means for the drum, a gear box interposed in the drive means for the tachometer to coordinate the operation thereof with the rotation of the drum, and a slip clutch interposed between the gear box and the tachometer.

3. In combination with a truck-mounted cement mixer having a rotating drum and drive means to rotate said drum first in one direction and then in a reverse direction, the improvement therewith comprising a tachometer to count the number of revolutions of the drum in one direction to thereby measure the texture of the cement mix, drive means interconnecting the tachometer and the drum, and a slip clutch interposed in the drive means for the tachometer, said clutch disconnecting said drive means from the tachometer when the drum is rotated in a reverse direction.

References Cited in the file of this patent UNITED STATES PATENTS 1,148,125 Stewart July 27, 1915 1,182,022 Larson May 9, 1916 Berge Nov. 2, 1926