US 2549718 A
Description (OCR text may contain errors)
April 17, 1951 w. F. SPANG SCR=APER UNIT FOR ENDLESS MOVING SURFACES Filed July 17, 1948 lfwezzfow:
mma F E6 1mm f 2 Patented Apr. 17, 1951 SCRAPER UNIT FOR ENDLESS MOVING SURFACES William F. Spang, Miltonj Mass assignor to Cube Steak Machine 00., Needham Heights, Mass.,' a
partnership Application July 17, 1 948, Serial No. 39,360
This invention relates to a novel cleaning unit for endless moving surfaces such as wheels, band saws, etc. Smooth and efficient running of such apparatus requires that these surfaces which come into cooperating contact shall be kept free a tangential position which has not performed the desired operation efficiently. I have discovered that a cleaning unit disposed substantially normal to the surface to be cleaned will perform 1 Claim. (01. 143-29) duced inner end of the detent 28. It will be apparent that this circular construction of the plunger [6 and the cooperating bore within the block provide a structure that can be produced economically and with great precision. This construction together with the one-piece block 20 provides a strong and superior support for resisting the cutting thrusts against the the cleaning operation in superior manner and the primary object of my invention resides in the production of an improved unit thus constructed and operated for this purpose. These and other features of the invention will be best understood and appreciated from the following description of a preferred embodiment thereof selected for purposes of illustration and shown in the accompanying drawings in which;
Fig 1 illustrates diagrammatically a band saw unit employing my invention,
Fig. 2 is a rear end elevation of my improved surface cleaning unit,
Fig. 3 is a side elevation thereof, partially in section, and
Fig. 4 is a plan elevation, partially in section. In Fig. 1 I have illustrated a band saw l0 supported on three wheels or rolls l2. The cooperating surfaces of the saw and wheels must be kept free from dirt, grit and the like if the cooperating parts are to function efficiently. Jihe improved unit M which I have invented for performing llhlSifllllCtiOn is mounted to operate at an angle normal to the surface being cle' ed tooth J8 .terminates in a sharp cutting ed g e;."l9.
The block 2|] is open at its forward end to receive the plunger and its rear end is provided with a hole 22 for receiving the smaller rear end 24 of the plunger. A compression spring 26 normally forces the plunger forwardly and a detent 23 is provided for holding the plunger against rotation. As illustrated in Fig. 2 the forward portion, I6, of the plunger is circular in cross section and has a longitudinal key slot therein receiving the replunger and provides for quick and easy assembly and disassembly of the unit. The block 20 is supported in a bracket 3|] provided with a spring pressed detent 32 for holding it within the bracket.
Each wheel I 2 illustrated in the drawing has a saw supporting periphery 33 grooved circumferentially and the cutting extremity IQ of the tooth I8 is formed to fit this grooved surface as shown in Fig. 4. The bracket 30 and block 20 support the plunger I6 for sliding movement normal to the surface to be cleaned. The tooth [8 has a top surface 34 extending rearwardly from the cutting extremity l9 and disposed in a plane substantially normal to the surface 33 and a bottom surface 35 diverging from the top surface from the extremity l9 rearwardly. Thus the tooth l8 provides a sharp cutting edge always held in cutting contact with the surface 33 by the spring 26 and adapted to keep the surface 33 clean of all foreign matter that would interfere with the operation of the machine.
The block 20 can be removed for repair or replacement merely by releasing the detent 32 and the plunger is freely removable forwardly from the block. The invention therefore provides a unit which can be easily removed and replaced and which serves the intended function with maximum efficiency.
Havingthus disclosed my invention, I claim as new and desire to secure by Letters Patent:
A scraper unit for endless moving surfaces,
comprising a one-piece block having a straight bore circular in cross sectionextending thereinto from its forward face to an end wall at the rear face and a boreof reduced diameter through the wall coaxial with the-first bore, a plunger slidable longitudinally in the bores and having a forward portion fitting the larger bore and a rear portion fitting the smaller bore, the forward portion of the plunger having a key slot longitudinally therein, a releasable detent extending into the key slot and preventing rotation of the plunger but permitting its movement longitudinally, a scraping tool with a sharp cutting extremity on the forward end of the plunger outside of the bore, resilient means-normally forcing the plunger forwardly, a support disposed outside of and having an opening therein receiving and closely fitting the block, and a releasable detent carried by the support for engaging and holding the block in place therein.
WILLIAM F. SPANG.
REFERENCES CITED UNITED STATES PATENTS Name Date Ide Nov. 28, 1871 Number Number 10 Number Name Date Hoffman Dec. 17, 1889 Chamberlain Aug. 19, 1930 Jinnett Feb. 21, 1933 Biro May 18, 1937 Blank July 23, 1940 BiIO 1 July 1, 1947 FOREIGN PATENTS Country Date Great Britain July 7, 1921