US2821214A - Adjustable double log dog for sawmills - Google Patents

Description

Jan. 28, 1958 R. Q, JUREK ADJUSTABLE DOUBLE LOG DOG FQR SAWMILLS Filed Feb. 21, 1956 2 Sheets-Sheet 1 Raymond C. Jurek INVENTOR.

BY Q4 I MMHM Jan. 28, 195 R. c. JUREK ADJUSTABLE DOUBLE LOG DOG FOR SAWMILLS 2 Sheets-Sheet 2 Filed Feb. 21, 1956 Raymond G. Jurek INVENTOR.

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ww a 1 United States Patent ADJUSTABLE DOUBLE LOG-DOG FOR SAWMILLS Raymond C. Iurek, Virginia, Minn.

Application Februar-y 21,1956, SerialxNo. 566,943

This inventionrelatesin general: to new. and useful improvements in sawmill constructions, ,and morev specifically to. anii'nprovedlog dogv assembly.

In order that a log may be retained in position during a sawing operation, the head blocks are provided with suitable: log dogs for gripping the log. and retaining it? in position. The logdogs generally include upper and lower dogs which are disposed in opposed relation: and which grip the. log therebetween. In. order to engage the log dogswith. the log,.it is necessary that the dogs be advanced or retractedaway from a knee of the headblock dependi'ng upon the diameter of the log and also be moved vertical. withrespect to each other to clampa log therebetween. Normally this isdone manually with the result that it is not only timeconsuming. but requires considerable work upon-the operator of the sawmill. In-fa'ct, most installations require the use of one manfor operating the sawmill and another man for operating. the log, dogs;

It is therefore theprimary object of this invention to provide. an improved. log dog assembly which includes; a fluid-cylinder. connected to-the log dogs whereby by turne ing a. simple control handle the operator of the sawmill may openor close the logdogs as desired without efliort out his part.

Another object of this invention is to' provide improved log dog assembly whichv includes an upper'dog: and a lower dog mounted for movement away from and towards: each other, there also being provided means connected to the log dogs which permits the simultaneous movement of the log dogs in and out together.

Still. another object of: this invention is to provide an improved log dog assembly which employs a-fluidl cylinder which is so constructed whereby itrnay be easily attached to the knees of existing sawmills.

Afurther. object of this invention is toprovide an. improved log. dog assembly which has an extremely simple control. whereby a sawmill operator may operate the log dog with amim'mum of effort so that one person may both set the log on the sawmill and operate the sawmill.

These together withother objects and advantages which will. become subsequently apparent reside in the. details of construction and operation as more fully hereinafter described and claimed, reference being bad to the accompanying drawings forming a part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is an elevational view of a head block of a sawmill and shows positioned thereon a log, the log being clamped on the head' block by means of the log dog assembly which is the subject of this invention;

Figure 2' is a front view of the log dog assembly removed from the head block and shows the specific details thereof;

Figure 3 is a fragmentary elevational view similar to Figure 1 and shows the upper log dog in an elevated position;

Figure 4 is anenlarged transverse vertical sectional view tional view taken substantially upon the plane indicated by thesection-line. 5=5 of-FigureZ and shows further. the.details-of anoperator for moving thelog dogsint-and. out;.and

Figure. 6 (Sheet 1,) is an enlarged fragmentary verticalsectionalcview taken substantiallyupon'the planeindicated; by the section line 6:6. of Figure-5. and. showsifurther the'detailsof the'operator for moving the logdogs in and out.

Referring nowto Figure. 1, in particular,it will be seentha trthere i s'illustrated.detailsofa sawmill which include; a head. block. 10? having adjustably mounted" thereon as knee:12.. Carriedibythe knee 12 is thelog dog assembly, which.-is?the subject ofi'thisiinvention thelog dogassembly beingreferred. to inageneral by therreference. numeral. 14;. The log: dogg'assembly 14-is illustrated. as gripping-a log 1T6 andretainin'g it-iin-positiontontthe; head block 10;

The-log dog1assembly'14' includes a mounting bracket: which isireferredto-in general by the reference numeral 18. The mounting bracket 18 is formed. Ofi avertical strap. 20" which has secured. to the lower end thereof a plate 22-. A similar plate-24 is securedto the upper ends of the strap 20. The. strap 20 is'suitabliy'securedi tothe knee in the position best illustrated in Figure 1..

Referring now" to-Figure-4 ill-particular, it will be seen that. theplates 2-2? and- 24: are provided: with: aligned slots 26 and 28, respectively; Slidahly received in the slots 26 and ls forz guided movement isa. slide bar 30'. The slide bar 30 1s vertically. disposed: and has secured to the upper' end thereof'. by means of. suitable: clamps 32 a cylinder 34 of a fluidmntor which isreferred' to in: general by the. referencenumeral 36. Slidably" positioned withincylinder'3r4i's a piston 38 which has eonnected thereto an elongated pistorc rod'40; The piston rod 40 passes through; a bore 42 in the upper platev 2 b and is: guided relative thereto;

In order that. the fluid. motor 36" may be controlled; there'isaprovided avalive144'. The valve 44 hasconnected thereto an air line 46 (Figures 1" and 3 whichmay be connected: tosany'desire'd compressed-supply; Extend ing: from the" valve 44':- and connected to opposite ends of the cylinder 343are: lines 48 and 50 The'valve 4'4 is provided with aisuitable handle-52 for operating the same. B'y selectively positioning the handle 52, the piston- 38 is moved: up or down in the cylinder 34.

Securedto' the lower endof the slide bar 30forlimited movement: therewith is a lower dog assembly which is referred to'ii'n general by the reference numeral 54. The lowerdog. assembly 54 includes a lower support 56' (Figure 4) which-is secured' directly to the slide bar30: Eittending: transversely through the lower support 56 is a lower dog 58'. The dog 58 includes a rackportion' 59 (Figure 1.) to facilitate th'e positioning thereof.

Iournaled; in tlre pl'ates 22 and 24 is a vertically'ext'end ing: shaft: 60.. Theshaft sods mounted for both rotation and vertical sliding movement. Carried by the lower support 56 jounnalz block: 62 in:which the=1ewer end of the. shaft 60 is: journaled; Secured on the extreme lower end of the shaft 60 is a gear 64 which is meshedwith the rack 60 of the dog: 58; By rotating: the: shaft 60,, the rack. 59 is driven by the gear. 64 with the result that. the. lower dog 58: is moved in: or out; asdesired with respect tothe. support. 56.

Slidably mounted on the slide. bar 30 intermediate. the plates 22 and; 24 is an upper. dog, assembly which is referredto in general by the, reference numeral 66. The upper dog assembly 66 includes an upper support 68 which is g d 'figly positioned on the slide bar 30. se-

Patented Jan. 28, 1958.

port 68 by means of a collar 72 which is threadedly engaged in a threaded lower portion74 of the piston rod- 40, the collar 72 being disposed between the ears 70.

' The shaft 60 also extends through the ears-70 and is suitably journaled therein for both rotation and vertical sliding movement. The shaft 60 also includes an elongated keyway 76. Positioned between the cars 70 and suitably keyed to the shaft 60 is a gear 78. Positioned above the uppermost ear 70 and also keyed to the shaft 60 for vertical sliding movement is a crank 80. The crank 80 includes a-latch element 82 which is engaged with a segment ring 84 having a plurality of circumferentially spaced notches 86 for receiving the latch 82. The latch 82 is pivotally mounted on a pivot pin 88 and normally seats in one of the notches 86. In order that the latch 88 may be selectively moved to an inoperative position, there is carried by the crank 80 a sleeve 90 in which there is mounted a spring 92. Disposed within the spring 92 and connected to the latch member 82 is a pin 94 having a button 96 on the upper end thereof. By depressing the button 96, the latch member 82 is moved to an inoperative position and the crank 80 is free to be rotated to rotate the shaft 60 whereby the gears 64 and 78 may be rotated.

Slidably carried by the upper support 68 is an upper dog 98. The upper dog 98 includes a rack portion 100 which is meshed with the gear 78.

In the operation of the log dog assembly 14, a log, such as the log 16, to be sawed is positioned on the head block in abutment with the knee 12. At this time the lower dog 58 and the upper dog 98 are separated, the lower dog 58 being in a lower point of travel out of the way of the log 16 and the upper dog 98 being vertically elevated, as is best illustrated in Figure 3. In the movement of the crank 80 will be necessary to properly position the dogs 58 and 98.

It is pointed out that the dogs 58 and 98 are disposed on the left side of the slide bar 30, as is illustrated in Figure 4. If desired, the gears 64 and 78 may be made smaller or moved further away from the slide bar 30. In such event, the dogs 58 and 98 may be moved to the right of the slide bar 30 if it is so desired.

,. A resilient stop assembly 102. (Figures 2 and 4) is carried by the plate 24. The stop assembly 102 includes a stop member 104 having a stem 106 slidably passing through the plate 24. A spring 108 is carried by the stem 106. An angle member'110 is carried by event the dogs 58 and 98 project farther enough away from the knee 12, it will not be necessary to move in or out with respect to the supports 56 and 68. Thus once the log 16 has been pushed against the knee 12, it is merely necessary for the operator of the sawmill to turn the handle 52 to the desired position. This will result in the piston 38 moving downwardly so that the piston rod will also move downwardly to move the upper dog 98 into engagement with the log 16. Once'the dog 98 engages the log 16, the downward movement of the piston 38 will substantially stop and as a result the cylinder 34 will move upwardly. This will result in the upward movement of the lower dog 58 to the position illustrated in Figure 1. Further movement of the piston 38 with respect to the cylinder 34 will result in the effective clamping of the log 16. Inasmuch as the operator merely has to turn the handle 52 to position the dogs 58 and 98, it will be readily apparent that the operation of the log dog assembly 14 is extremely simple and requires no hard work on the part of the sawmill operator. After the log 16 has been fully sawed,'it is released from the head block 10 by turning the handle 52 in the opposite direction. This will result in the simultaneous upper movement of the piston 38 and the downward movement of the cylinder 34, so as to move the dogs 58 and 98 apart.

In the event a log of a difierent size from the log 16 is to be mounted on the head block 10, it may be necessary to either advance or retract the dogs 58 and 98. This is accomplished by merely releasing the latch member 82 and rotating the crank 80 in any desired direction. Inasmuch as the crank 80 drives the shaft 60 which in turn drives the twogears 64 and 78, it will be readily apparent that the dogs 58 and 98 are either advanced or retracted simultaneously. Because of the ratio between the gears 64 and 78 and the rack portions 59 and-100, respectively, it will be seen thatonlya slight the slide bar 30 in alignment with the stop member 104.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it, is not desired to limit ,the invention to the exact construction'and operation shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

Whatis claimed as new is'as follows:

1. A log dog assembly comprising a mounting bracket, a slide bar supported by said mounting bracket for limited vertical sliding movement,'an upright fluid motor, said fluid motorincluding a cylinder secured to an upper end of said slide bar, a piston rod projecting downwardly from said cylinder, a lower dog supported by and for up I and down movement with said slide bar at the lower end of said slide bar, an upper dog slidably mounted for vertical movement on said slide bar, said upper dog being connected to said piston rod.

2. A log dog assembly comprising a mounting bracket, a slide bar supported by said mounting bracket for limited vertical sliding movement, an upright fluid motor, said fluid motor including a cylinder secured to an upper end of said slide bar, a piston rod projecting downwardly from said cylinder, a lower dog supported by and for up and down movement with said slide bar at the lower end of said slide bar, an upper dog slidably mounted for vertical movement on said slide bar, said upper dog being connected to said piston rod, control means for said fluid motor mounted on said mounting bracket.

I 3. A log dog assembly comprising a mounting bracket, a slide bar supported by said mounting bracket for limited vertical sliding movement, an upright fluid motor, said fluid motorincluding a cylinder secured to an upper end of said slide bar, a piston rod projecting'downwardly from said cylinder, a lower dog supported by and .for up and down movement with said slide bar at the lower end of said slide bar, an upper dog slidably mounted for vertical movement on said slide bar, said upper dog being connected to said piston rod, means connected to said upper and lower-dogs for simultaneously extending and retracting said upper and lower dogs relative'to said slide bar.

4. A log dog assembly comprising a mounting bracket, a slide bar supported by said mounting bracket for limited verticalsliding movement, an upright fluid motor, said fluid motor including a cylinder secured to an upper. end of said slide bar, a piston rod projecting downwardly from said cylinder, a lower support carried by the lower end of said slide bar, a lower dog carried by said lower support for up and down movement with said slide .bar, an upper support carried by said piston rod, said upper support being vertically slidably mounted on said slide bar, an upper dog carried by said upper support, means connected to said upper and lower dogs for simultaneously extending and retracting said upper and lower dogs relative tosaid upper and lower supports andsaid slide bar.

5. A log dog assembly comprising a mounting bracket, a slide bar supported by said mounting bracket for limited vertical sliding movement, an upright fluid motor, said fluid motor including a cylinder secured to an upper end of said slide bar, a piston rod projecting downwardly from said cylinder, a lower support carried by the lower end of said slide bar, a lower dog carried by said lower support for up and down movement with said slide bar, an upper support carried by said piston rod, said upper support being vertically slidably mounted on said slide bar, an upper dog carried by said upper support, means connected to said upper and lower dogs for simultaneously extending and retracting said upper and lower dogs relative to said upper and lower supports and said slide bar, said means including racks on said upper and lower dogs, a shaft carried by said mounting bracket for rotation and vertical sliding movement, gears connected to said shaft for rotation with said shaft, said gears being meshed with said racks.

6. A log dog assembly comprising a mounting bracket, a slide bar supported by said mounting bracket for limited vertical sliding movement, an upright fluid motor, said fluid motor including a cylinder secured to an upper end of said slide bar, a piston rod projecting downwardly from said cylinder, a lower support carried by the lower end of said slide bar, a lower dog carried by said lower support for up and down movement with said slide bar, an upper support carried by said piston rod, said upper support being vertically slidably mounted on said slide bar, an upper dog carried by said upper support, means con-' nected to said upper and lower dogs for simultaneously extending and retracting said upper and lower dogs relative to said upper and lower supports and said slide bar, said means including racks on said upper and lower dogs, a shaft carried by said mounting bracket for rotation and vertical sliding movement, gears connected to said shaft for rotation with said shaft, said gears being meshed 6 with said racks, one of said gears being retained by said upper support for movement therewith, said one gear being keyed on said shaft for relative sliding movement.

7. A log dog assembly comprising a mounting bracket, a slide bar supported on said mounting bracket for limited vertical sliding movement, an upright fluid motor, said fluid motor including a cylinder secured to an upper end of said slide bar, a piston rod projecting downwardly from said cylinder, a lower support carried by the lower end of said slide bar, a lower dog carried by said lower support for up and down movement with said slide bar, an upper support carried by said piston rod, said upper support being vertically slidably mounted on said slide bar, an upper dog carried by said upper support, means connected to said upper and lower dogs for simultaneously extending and retracting said upper and lower dogs relative to said upper and lower supports and said slide bar, said means including racks on said upper and lower dogs, a shaft carried by said mounting bracket for rotation and vertical sliding movement, gears connected to said shaft for rotation with said shaft, said gears being meshed with said racks, one of said gears being retained by said upper support for movement therewith, said one gear being keyed on said shaft for relative sliding movement, drive means for said shaft supported by said upper support.

References Cited in the file of this patent UNITED STATES PATENTS 484,332 Martin et al Oct. 11, 1892 1,724,010 Ferris Aug. 13, 1929 1,772,052 Martin Aug. 5, 1930 2,626,640 Cahoon Ian. 27, 1953 2,661,779 Saunders Dec. 8, 1953

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