US3815738A

US3815738A - Log sorting method and apparatus

Info

Publication number: US3815738A
Application number: US00272019A
Authority: US
Inventors: H Sweet; R Papworth; J Grimm
Original assignee: MARPLEX PROD CO Inc; HERMAN ENG CORP
Current assignee: MARPLEX PROD CO Inc; HERMAN ENG CORP
Priority date: 1972-07-14
Filing date: 1972-07-14
Publication date: 1974-06-11
Anticipated expiration: 1991-06-11

Abstract

A log sorting method and apparatus in which logs are conveyed on a flat, continuous conveyor between the arms of a plurality of ejector yokes. A kicker rail is connected to one set of arms on one side of the conveyor and a longer retainer rail is secured to the arms on the other side of the conveyor. When the yoke is at rest, these rails are generally continuous with the remaining side rails of the conveyor. The logs are scanned for minimum diameter and those with the largest minimum diameter are ejected from the conveyor by the first ejector yoke. Progressively smaller logs are ejected at successive stations. If there is no gap between the logs as they come to an ejector, as determined by an energy transmitting beam passing across the conveyor, then the logs will not eject. The logs are normally ejected into receiving bins, but can be diverted to the return side of the conveyor or to a second parallel conveyor, which carries them to another ejector which in turn ejects them onto a live deck from whence they are carried to the saws or to some other operation or location.

Description

Sweet et at.

[ LOG SORTING METHOD AND APPARATUS {75] Inventors: Harold J. Sweet, Rhinelander, Wis;

Robert L. Papworth, Chassell. Mich; John G. Grimm, Jr., Tripoli. Wis.

[731 Assignees: Marple? Products Company Inc.,

Rhinelander, Wis; Herman Engineering Corporation, Houghton, Mich.

[22] Filed: July 14, 1972 [21] Appl. No.: 272,019

52 us. C1. 209/82 [51] Int. Cl. B07c 5/04 [58] Field of Search 209/73, 74, 75, 82, 86, 209/88, 111.9, 111.7; 198/185, 24; 33/174 P, 174 PA [56] References Cited UNITED STATES PATENTS 3.138.258 6/1964 Stupfel et a1 209/82 3,631,977 l/1972 Taul 209/82 X Primary Examiner-Lloyd L. King Assistant ExaminerGene A. Church Attorney, Agent, or FirmPrice, Heneveld, l-luizenga & Cooper June 11, 1974 ABSTRACT A log sorting method and apparatus in which logs are conveyed on a flat. continuous conveyor between the arms of a plurality of ejector yokes. A kicker rail is connected to one set of arms on one side of the conveyor and a longer retainer rail is secured to the arms on the other side of the conveyor. When the yoke is at rest, these rails are generally continuous with the remaining side rails of the conveyor. The logs are scanned for minimum diameter and those with the largest minimum diameter are ejected from the conveyor by the first ejector yoke. Progressively smaller logs are ejected at successive stations. If there is no gap between the logs as they come to an ejector, as determined by an energy transmitting beam passing across the conveyor, then the logs will not eject. The logs are normally ejected into receiving bins, but can be diverted to the return side of the conveyor or to a second parallel conveyor, which carries them to another ejector which in turn ejects them onto a live deck from whence they are carried to the saws or to some other operationor location.

88 Claims, 6 Drawing Figures PATENTEDJuu 1 1 m4 SHEET 10F 3 ale-15738 PATENTEnJuu 1 1 I974 sum 3 OF 3 LOG SORTING METHOD AND PATUS BACKGROUND OF THE INVENTION This invention relates to sorting logs for subsequent sawing or other operations. Log sorting systems generally employ conveyors to carry logs past ejector mechanisms. However, logs tend to be difficult to handle, and sometimes fall ofi these conveyors or become jammed. Thus, some prior art sorters employ complicated mechanisms to prevent these problems. For example, one prior art system employs special carriages in conjunction with the conveyor means. Other systems employ extremely complicated ejector mechanisms.

Typically, prior art sorting systems must be run at a rate of 50 feet per minute or slower in order to avoid jamming. If logs move past an ejector while abutting endwise, the ejection of a first log may knock the second askew on the conveyor. The skewed log then jams and the entire system must be shut down.

In most such systems, logs are ejected into storage bins from which they are transferred by fork lift trucks or the like to the saws. While this procedure is generally acceptable, it involves double handling and it is too slow and cumbersome when there is no backlog of logs in storage and a particular size of log is needed immediately.

Sorting systems generally sort logs according to length only. One system sorts the logs to top end dimension. However, prior art systems have not sorted to minimum diameter, apparently because of the difficulty of coordinating the scanning of an entire log with operation of the sorting system. While prior art measuring systems have been devised to determine minimum diameter, they have not been coordinated with a sorting system.

Unfortunately, the teachings relative to the sorting of other objects have generally not been applicable to the sorting of logs. The problems associated with sorting bulky, irregular logs appear to be unique.

SUMMARY OF THE INVENTION In the present invention, logs are conveyed along a predetermined path and a plurality of ejection stations are established at which logs might be ejected from the conveying means. Each log is individually scanned at each ejection station to determine whether or not it has a predetermined minimum diameter. If it does it is ejected from the conveying means. Those logs having the largest minimum diameter are ejected at the first ejection station with progressively smaller logs being ejected at successive ejection stations. By placing an energy transmitting beam projector and receiver generally at each end of each ejection station, one has a fairly good indication of whether the log has the desired minimum diameter. It is preferable to keep a projector or receiver out of the gap area through which a log is ejected. Thus in the preferred embodiment, the projectors or receivers on one side of the conveying means are spaced at opposite ends of the ejection station and the beams are directed diagonally and inwardly across the conveying path. This insures that the beam will be broken by the ends of the log at precisely the moment when it is to be ejected. The use of an energy transmitting beam is preferable to mechanical detecting means since it facilitates greater accuracy in measurement.

In a more preferred aspect of the invention, the minimum diameter of a log is determined by using only one energy transmitting beam projector and receiver generally at the upstream end of an ejection station. Broadly, this aspect of the invention includes positioning a sensing means along the path along which logs are conveyed for sensing the approximate diameter of a log at each point along the length of the log as the log passes the sensing means. A timing means is operably connected to the sensing means and is activated in response to the sensing of a predetermined minimum diameter at a given point along the length of the log. An ejector yoke is operably connected to the timing means and is activated thereby only after the timing means has remained continuously activated for a predetermined length of time. Specifically, the timing means effects closure of a timed contact after having been continuously activated for a predetermined length of time. This timed contact is in series with a control means which effects activation of the ejection means. Also in series with the timed contact and the control means is a normally closed limit switch. The normally closed limit switch is operably connected with the ejector switch in such a way that when the ejector means has completely ejected a log, it opens the limit switch, thereby deactivating the control means and allowing the ejection means to return to its normal position. Finally, since the timed contact will again open as soon as the log passes the sensing means, a holding circuit is provided in parallel with the timed contact, but in series with the normally closed limit switch and the control means. The holding circuit includes a contact which is closed upon activation of the control means, but which is opened when the limit switch is opened, thereby deactivating the control means.

In order to minimize jamming, means are employed for determining whether or not there is a gap between adjacent logs as they approach an ejection station. If there is no gap, the lead log is not ejected, even if it meets the predetermined minimum diameter requirement. The logs are allowed to pass on until the following log reaches the particular ejection station for which a log having its minimum diameter should be ejected. The following log is ejected at that station and the lead log is ejected at the next ejection station. Specifically, a gap sensing means closes a gap contact if there is a gap between adjacent logs. This gap contact is in series with the timed contact referred to above and with the control means and limit switch. Like the timed contact, however, the gap contact is in parallel with the holding circuit. Thus, even if a log enters into a space where a gap previously existed, the control means which activates the ejector means will remain closed until a log is completely ejected and the limit switch is opened.

A simple, generally flat, continuous belt conveying means is employed in the system. To prevent logs from falling off the conveyor, the ejector means employed is a yoke pivotally mounted above the conveying means at each ejection station. Preferably, the belt is flexible laterally inwardly and conforms to the concave shape of a belt supporting means when loaded with logs. This further minimizes the chances of logs falling off. This also minimizes the chances of logs aligning side by side and thereby jamming the system. The yoke includes arms disposed at either side of the conveying means whereby a log traveling on the conveying means is embraced by the yoke arms. When a log is to be ejected,

the yoke is pivoted and one of the embracing arms kicks the log free. Preferably, the yoke includes a retainer rail operably connected to an arm on one side of the conveyor and forming a generally continuous retaining means along the side ofthe conveyor. When the yoke is pivoted, the retaining rail is moved out of the way leaving a gap in the retaining means which is large enough to allow a log to pass therethrough. The other arm of the yoke includes a kicker rail which is shorter in length than the retaining rail and which has its lead edge spaced downstream from the lead edge of the retaining rail. This insures that even though two logs are passing fairly close together on the conveying means,

the kicker rail does not inadvertently catch the front end of a following log or the back end of a preceding log as it sweeps the lead log out through the gap.

Yet another aspect of the invention relates to a means for directing logs directly to the sawing or other subsequent operations as they are sorted. Normally, the

logs will be ejected from the conveying means into receiving bins at the side of the conveying means. Here they will be stored or will be transferred to storage until such time as logs of that particular size are to be processed. However, the present invention employs a return conveying means adjacent to the sorter conveying means for conveying logs directly to a sawing apparatus. A divertor means is positioned adjacent the sorting conveyor means and adjacent each receiving bin. The divertor means can be adjusted to a first position for diverting logs ejected from the conveyor means from the receiving bin to the return conveying means. It can be adjusted to another position in-which logs are ejected directly into the receiving bins;

The result is a log sorting system capable of operation I at a rate of 200 feet per minute. The attainment of this result as well as other objects and advantages of the present invention will be more fully understood and appreciated by reference to the written specification and appended drawings.

BRIEF DESCRIPTION OF THE-DRAWINGS FIG. 1 discloses a side elevational schematic view of the log sorting apparatus;

FIG. 2 discloses a cross-sectional view'taken along plane Illl of FIG. 1;

FIG. 3 is a plan view of one ejector yoke assembly;

FIG. 4 is an end elevational view of one ejector yoke assembly;

FIG. 5 is a schematic showing of a log passing the energy transmitting beam detectors; and

FIG. 6 is an electrical schematic of the control system for an ejector mechanism.

PREFERRED EMBODIMENT In the preferred embodiment, logs l are conveyed on a sorter conveyor 10 past a plurality of ejector yokes (FIG. 1). A minimum diameter scanning assembly mounted on the supporting frame gages the approximate minimum diameter of a log passing through ejector yoke 20 and determines whether or not it has a particular predetermined minimum diameter (FIG. 3). Gap determining assembly at the upstream end of each ejector yoke 20 determines whether or not there is a gap between adjacent logs traveling on conveyor 10. If such a gap exists, and if the log has the specified minimum diameter required, ejector yoke 20 will be activated and the log will be ejected from conveying means 10. Logs having the largest minimum diameter are ejected at the first ejector yoke 20 and successively smaller logs are ejected at successive ejector yokes 20.

Normally, these logs are ejected into receiving bins (FIG. 1). However, divertor gate can be adjusted to the position shown inphantom in FIG. 2 to divert logs from receiving bin 60 onto a return conveyor 80. Return conveyor conveys the logs to a live deck ejector 81 which ejects the logs onto a live deck 90. From live deck 90, logs are conveyed by mill conveyor 100 directly to the saws. Thus if there is a need for a particulartype of log as the logs are being sorted, that particular diameter log can be diverted directly to live deck and ultimately to the saws.

Sorter conveyor 10 comprises the upper portion of a flexible, continuous belt 11 mounted for continuous movement ina conventional fashion such as around wheels 12 mounted on frame 40 (FIG. I). The conveying assembly includes side rails 13 at least at one side thereof to cooperate with the downwardly depending arms of ejector yokes 20 to prevent logs from falling off conveyor 10. Continuous belt 11 is generally flat, but is preferably flexible laterally such that it tends to flex into a concave or dish shape when loaded. Specifically, it tends to conform to the concave shape of top portion 450 of cross supports 45 and thereby makes it more difficultfor a log to fall off.

Ejector yokes 20 are pivotally mounted to frame 40 above sorter conveyor 10, and open downwardly thereonto. Each ejector yoke 20 comprises a pivot axle 21 formed of anelongated tube or the like having ejector sidearms 22 extending laterally and downwardly therefrom to the side of sorter conveyor 10 from which logs are ejected. On its opposite side, it includes a plurality of kicker arms 23 extending laterally therefrom and downwardly onto the kicker side of sorter conveyor 10.

Mounted to ejector side arms 22 is a retainer rail 24. Retainer rail 24 is an elongated member which acts as a closure for a gap at the side of sorter conveyor 10. The gap is large enough for a log to pass through. Retainer rails 24 of adjacent ejector yokes 20 cooperate to form a generally continuous retaining means at the ejector side of sorter conveyor 10.

Secured to the ends of kicker arms 23 is an elongated kicker rail 25. However, kicker rail 25 is shorter in length than retainer rail 24 and its lead or upstream end 25a is spaced downstream from the lead end 24a of retainer rail 24. This helps to insure that when two logs are moving fairly close together along sorter conveyor 10, kicker rail 25 will not inadvertently catch the front end of the following log as it knocks the lead log off of sorter conveyor 10. A blocking plate 28 is secured to the lead end 25a of kicker plate 25 and when yoke 20 is pivoted into its eject position, blocking plate 28 extends across the path defined by sorter conveyor 10 and prevents any logs from passing behind its lead end while it is in its ejection phase (see the phantom show ing in FIG. 4).

In order to effect pivotal movement of ejector yoke 20, a cylinder 27 is mounted with one pivotally joined to a kicker arm'23 and with its other end secured to frame 40 (FIG. 2). (Cylinder 27 not shown FIG. 3 for convenience). When ejector yoke 20 has been pivoted to a predetermined point, the end of retainer rail 24 engages a limit switch 26 which is mounted on a bracket 26a which is in turn connected to frame 40. This causes cylinder 27 to return, thereby returning ejector yoke 20 to its normal position.

Minimum diameter scanning assembly 30 comprises an ultrasonic beam projector 31 and an ultrasonic beam receiver 32 mounted to frame 40 generally at the lead and rear ends of ejector yoke 20. The projector and receiver at the rear end of ejector yoke 20 are labeled 31a and 32a for clarity.

The projectors 31 and 31a and

receivers

32 and 32a are positioned at a height above sorter conveyor corresponding to the minimum diameter which a log must have to be ejected at the particular ejector yoke where they are located. Thus, if it is desired to eject logs having a minimum diameter of 12 inches, the projectors and receivers are set approximately 12 inches above the level of sorter conveyor 10.

The projector 31 is mounted to the main frame upright 41 on the ejector side of conveyor 10. A secondary frame upright 42 extends upwardly on the kicker side of conveyor 10 and joins the same top piece 43 as do the main uprights 41. Because kicker rail is shorter than retainer rail 24,, secondary upright 42 can be positioned inwardly, almost adjacent the point where pivot axle 21 of ejector yoke 20 is pivotally mounted to top piece 43 of frame 40. It is to this secondary upright 42 that each

receiver

32 or 32a is mounted. This causes the ultrasonic beam to project diagonally across the path of sorter conveyor 10 in an inward direction, generally towards the center of ejector yoke 20. In this manner, it can be insured that the projected beam at each end of a log passes within the end extreme of the log at the precise moment the log is in a position to be ejected through the gap normally closed by retainer rail 24. If the receiver 32 were mounted on main frame upright 41 directly opposite projector 32, then some type of delay circuit would have to be employed between the time the scanning system determined whether or not a log had a particular minimum diameter and the time at which the log was actually ejected. Further, it would be impossible to mount in this fashion a scanning assembly 30 at the rear end of ejector yoke 20, since the log would not be measured thereby until it had actually passed the point where it could effectively be ejected without being jammed into a main upright 41.

The use of a scanning assembly 30 at each end of a log as it passes through ejector yoke 20 gives a fairly good approximation of the minimum diameter of a log. Naturally, it would be possible for the log to have a smaller minimum diameter at some point in its center than at either end. However, one can be fairly certain by checking two points of the log, particularly near the ends that one has determined the minimum diameter of the log. This is because the top end of the log is generally narrower since it is farther up the tree. By placing sensor 30 at both ends of a log, one need not be concerned about which way the log was originally inserted onto conveyor 10.

Frame 40 is comprised of steel beams and steel tubular members or the like and is the primary support for the entire log sorting apparatus. In addition to the main uprights 41, the secondary uprights 42 and the top pieces 43, the frame includes a plurality of side supporting beams 44 extending between adjacent main uprights 41 below both sorter conveyor 10 and return conveyor 80 (FIG. I). Extending between these are a plurality of cross supports 45 which act as supports for the upper and lower portions of conveyor belt 11 (FIG. 2). Supports 45 include a dish shaped or concave top piece 450 into which conveyor belt 11 tends to flex, particularly when loaded with a log. This further minimizes the chances of a log falling off sorter conveyor 10 or return conveyor 80.

It should be noted that the secondary supports 42 were not actually shown in FIG. ll because they would tend to clutter the drawing. Similarly, the lower supporting region of frame 40 which is shown in FIG. 2 was not specifically shown in FIG. 1 since FIG. 1 is intended to be primarily a schematic representation of the overall assembly.

Gap determining assembly 50 also comprises an ultrasonic beam projector 51 and a beam receiver 52 (FIG. 3). One assembly 50 is provided at the lead end of each ejector yoke 20. This assembly is placed fairly close to the surface of sorter conveyor 10 so that even the smallest diameter logs will block the beam as it passes by. The beam projected by projector 51 will first be broken by a lead log. If there is a space between adjacent logs on the conveyor, the beam will be received again by receiver 52 after the lead log is passed. If minimum diameter sensors 30 indicate that a log has a proper minimum diameter, and if a beam is received at receiver 52, a pair of switches will be closed which effects the opening of a solenoid which in turn activates.

the cylinder 27. If there is no gap between adjacent logs, the beam from projector 51 will remain unbroken and the abutting logs will pass by ejector yoke 20 even if the lead log has a proper minimum diameter for ejection.

The ultrasonic projectors and receivers are conventional in nature. One type of receiver and projector which has been applicable in the present invention is that manufactured by Delavan Manufacturing Company under the model designation Sonac Model OIL. An appropriate amplifier arrangement would be Sonac Model 31. Of course it is understood that while ultrasonic projectors and receivers are preferable due to the fact that they are less expensive, photoelectric beams or other types of energy transmitting beams could be utilized in practicing this invention.

Each receiving bin 60 includes a track 61 down which logs roll from sorter conveyor 10 (FIG. 2). Divertor gate is pivotally connected to this track assembly 61 and in a first position actually constitutes a part of the track. I-Iowever, divertor gate 70 is pivotally mounted to track 61 at 73 and can be rotated outwardly until it engages a stop 71, which is preferably mounted between the side walls 62 of track 61. In this alternative position, divertor gate 70 diverts logs ejected from sorter conveyor 10 onto a divertor track 72 which leads to return conveyor 80. Divertor track 72 extends from pivot mount 73 to a juncture with cross pieces 45 at the sides of return conveyor 80.

Return conveyor comprises the underside of continuous belt 11. It carries logs to a live deck ejector 81 which is identical in structure to ejector yokes 20 (FIGS. 1 and 2). Live deck and live deck ejector 81 are positioned ahead of the first ejector yoke 20 such that the logs from any ejector station can be returned to live deck 90 for immediate use. Live deck 90 itself comprises a deck upon which a plurality of logs to be sawedare piled. From thence they are picked up by mill conveyor and carried to the sawmill.

The minimum diameter scanning assembly described above employs two sets 30 of beam projectors and receivers, one set 30 positioned at each end of a log as it passes through an ejector yoke 20. These give fairly sound approximation of what the actual minimum diameter of a log is. However, a preferred means for determining minimum diameter has been invented. In this preferred system, only one beam projector 31 and only one beam receiver 32 are employed (FIG. When the beam between these two is broken by a log 1 passing therebetween, a timed contact 33 will close within a predetermined length of time unless the beam is again received at receiver 32 prior to the expiration of that predetermined length of time. Timed contact 33 is part of a timing circuit in which the contact is normally closed, but is held open and is allowed to close only after a time delay relay has been activated for a predetermined length of time. One appropriate timing circuit including such a timed contact and time delay relay is a unit manufactured by Delavan under the designation AC model 34.

The predetermined length of time is set and can be adjusted according to the speed of sorter conveyor and the length of logs l which are placed on sorter conveyor 10. The time delay of the circuit is set at a time which will result in an activation of ejector yoke just before the trailing end of a log 1 passes beyond the beam between projector 31 and receiver 32. Thus, if the logs are eight feet long, and sorter conveyor 10 is moving at two feet per second, 120 feet per minute, the timing circuit would be set to time out at approximately just under 4 seconds. If receiver 32 does not receive a beam for this predetermined length of time. timed contact 33 will close.

Time contact 33 is in series with gap contacts 53 (FIG. 6). Gap contacts 53 are controlled by gap determining assembly 50. If there is a gap between adjacent logs, a beam will pass from projector 51 to receiver 52 and gap contact 53 will be closed. The simultaneous closing of timed contact 33 and gap contact 53 allows a current to pass through normally closed limit switch 26 and through control relay CR. Control relay CR closes contacts CR, and CR The closure of contact V and if there is a gap between adjacent logs as indicated blocking of the beam would cause gap contact 53 to open. If it werent for the holding circuit through contactCR the opening of gap contact 53 would cause the deactivation of control relay CR and this in turn would cause cylinder 27 to remove to its start position without having ejected the log. It will be remembered that during the ejection operation, the blocking plate 28 of ejector yoke assembly 20. will prevent the closely following log from jamming up the system.

Thus, this preferred embodiment minimum diameter system provides a more positive determination of the minimum diameter of a log 1 by scanning the height of a log 1 above a conveyor along the entire length of the log.

OPERATION In operation, a plurality of logs are cut to any predetermined length and placed on sorter conveyor 10. On sorter conveyor 10, they are conveyed past the plurality of ejector yokes 20. As a log passes through an ejector yoke 20, it is scanned for minimum diameter and if it has a particular predetermined minimum diameter,

by gap determining assembly 50, the log will be ejected by ejector yoke 20. The simultaneous closing of switches controlled by minimum diameter scanning as-.

sembly 30 and gap determining assembly 50 activates cylinder 27 to pivot yoke 20 and cause kicker rail 25 to kick a log out through the gap at the side of sorter conveyor 10, which is left by retainer rail 24 being moved out of the way. Blocking plate 28 extending laterally from the lead end of kicker rail 25 is moved into position across the path of sorterconveyor l0 and acts to stop any logs which might be trailing too closely from passing behind kicker rail 25.

The largestlogs are ejected at the first ejector yoke I 20 and successively smaller logs are ejected at succes- CR activates solenoid 27a. Solenoid 27a in turn acti- V vates cylinder 27 which pivots ejector yoke 20 to thereby eject a log from the conveying assembly. When ejector yoke 20 reaches the extent of its pivot arc, it engages limit switch 26 and opens the same to thereby open the circuit through control relay. CR. Deactivation of control relay CR results in the opening .of contacts CR, and CR The opening of contact CR deactivates solenoid 27a and allows cylinder 27 to return to its normal position.

The purpose of contact CR is to establish a holding circuit in parallel with timed contact 33 and gap contact 53 and in series with control relay CR. This insures that once a gap has been determined to exist between adjacent logs by gap determining assembly 50, current will continue to flow to contact relay CR until ejector yoke 20 has completely ejected a log therefrom. This will be true even though a log might be following fairly close to the log being ejected. Such a following log might block the beam being projected by projector 51 after a gap has been initially determined. Such sive ejector yokes 20. The smallest logs, those below a particular predetermined minimum, pass directly off the end of sorter conveyor 10 and are carried onto a chipper orother process. (This is actually a final sorting station).

If it is desired to immediately cut a particular group of logs being sorted, divertor gate is adjusted ,to the I position shown in phantom in FIG. 2. This diverts the logs directly onto divertor tracks 73 and then onto return conveyor 80. On return conveyor 80, logs are conveyed to live deck ejector 81 A detector means such as an ultrasonic beam or the like detects the presence of a log at live deck ejector 81 and activates the same whereby logs are thrown downwardly onto live deck 90. From live deck 90, they are conveyed by mill conveyor to the saw.

Of course, it is understood that the above is merely a preferred embodiment of the invention and that many changes and alterations can be made without departing from the spirit and broader aspects of the invention.

The embodiments of the invention in which an exclusive property lows. r

l. A method for sorting logs comprising: moving said logs along a predetermined path; establishing a plurality of ejection stations along said path at which logs might be ejected from said path; scanning said logs at ameter of a passing log; ejecting from said path, at each or privilege is claimed are defined as folsaid ejection station, those logs having a predetermined minimum diameter, those logs having the largest minimum diameter being ejected at the first ejection station along said path with logs of progressively smaller minimum diameters being ejected at successive ejection stations.

2. A method for sorting logs comprising; moving said logs along a predetermined path; establishing a plurality of ejection stations along said path at which logs might be ejected from said path; scanning said logs at each said ejection station to determine approximately the minimum diameter of a passing log; ejecting from said path, at each said ejection station, those logs having a predetermined minimum diameter, those logs having the largest minimum diameter being ejected at the first ejection station along said path with logs of progressively smaller minimum diameters being ejected at successive ejection stations; determining whether or not there is a gap between adjacent logs when a given log is at a given ejection station; and ejecting a log at that ejection station only if such a gap is found to be present.

3. The method of claim 2 in which the existence or nonexistence of a gap is determined by projecting an ultrasonic beam across said path to be received by an ultrasonic receiver, the existence of a gap being indicated by the passage of said beam to said receiver.

4. The method of claim 3 in which said minimum diameter of a passing log is determined by passing an ultrasonic beam across the path of said log at a predetermined height approximately at each end of a log in position at a given ejection station, the presence of a desired predetermined minimum diameter being indicated by blockage of both said beams by a log positioned therebetween.

5. The method of claim 4 comprising: positioning one of a beam projector and beam receiver on one side of said path at each end of each ejection station, and at a distance apart which is greater than the length of a log to be ejected, whereby a log can be ejected therebetween; projecting a beam across said path, from or to said projector or receiver, in a diagonal inward direction towards the center of said ejection station whereby said beams are broken by a proper diameter log at the moment when they are in position to be ejected,

6. The method of claim 3 in which said minimum diameter of a passing log is determined by sensing the approximate diameter of a passing log at each point along the length thereof as it passes a preselected point along said path; activating a timing means in response to the sensing of a predetermined minimum diameter at a given point along the length of said log; ejecting said log from said predetermined path after said timing means has remained continuously activated for a predetermined length of time and to the simultaneous sensing of a gap between adjacent logs.

7. The method of claim 6 in which the step of ejecting said log includes the steps of: closing a first contact in response to the sensing of a gap between adjacent logs; closing a timed contact which is in series with said first contact after said timing means has remained continu ously activated for a predetermined length of time; activating a control means which is in series with said first contact and said timed contact in response to closing of saidcontact; and ejecting said log in response to activation of said control means.

8. The method of claim 7 comprising: closing a control relay contact which is in parallel with said first contact and said timed contact, and which is in series with said control means, in response to activation of said control means whereby said control means remains activated even if said first contact is opened in response to the sensing of a log at a point where a gap had previously been sensed; opening a normally closed limit switch which is in series with said first contact, said timed contact and said control relay and in series with said control relay contact, at the time a log is completely ejected from said predetermined path.

9. The method of claim 2 which also includes the step of blocking said predetermined path when a log is ejected therefrom at a point along said predetermined path behind the trailing end of the log which is being ejected.

10. A method for sorting logs comprising: moving said logs along a predetermined path; establishing a plurality of ejection stations along said path at which logs might be ejected from said path; scanning said logs at each said ejection station to determine approximately the minimum diameter of a passing log; ejecting from said path, at each said ejection station, those logs having a predetermined minimum diameter, those logs having the largest minimum diameter being ejected at the first ejection station along said path with logs of progressively smaller minimum diameters being ejected at successive ejection stations; receiving logs ejected at each ejection station in a receiving bin: selecting those logs being ejected at a particular ejection station and diverting them from their storage bin to a conveying means; conveying logs on such conveying means to a log sawing apparatus.

ll. A method for sorting logs comprising: moving said logs along a predetermined path; establishing a plurality of ejection stations along said path at which logs might be ejected from said path; scanning said logs at each said ejection station to determine approximately the minimum diameter of a passing log; ejecting from said path, at each said ejection station, those logs having a predetermined minimum diameter, those logs having the largest minimum diameter being ejected at the first ejection station along said path with logs of progressively smaller minimum diameters being ejected at successive ejection stations; said minimum diameter of a passing log being determined by passing an ultrasonic beam across the path of said log at a predetermined height approximately at each end of a log in position at a given ejection station, the presence of a desired predetermined minimum diameter being indicated by blockage of both said beams by a log positioned therebetween.

12. The method of claim 11 comprising: positioning one of a beam projector and beam receiver on one side of said path at each end of each ejection station, and at a distance apart which is greater than the length of a log to be ejected, whereby a log can be ejected therebetween; projecting a beam across said path, from or to said projector or receiver, in a diagonal inward direction towards the center of said ejection station whereby said beams are broken by a proper diameter log at the moment when they are in position to be ejected.

13. A method for sorting logs comprising: moving said logs along a predetermined path; establishing a plurality of ejection stations along said path at which logs might be ejected from said path; scanning said logs at each said ejection station to determine approximately the minimuum diameter of a passing log; ejecting from said path, at each said ejection station, those logs having a predetermined minimum diameter, those logs having the largest minimum diameter being ejected at the first ejection station along said path with logs of progressively smaller minimum diameters being ejected at successive ejection stations; said minimum diameter of a passing log being determined by sensing the approximate diameter of a log at each point along the length thereof as it passes a preselected point along said path; activating a timing means in response to the sensing of a predetermined minimum diameter at a given point along the length of said log; ejecting said log from said predetermined path after said timing means has remained continuously activated for a predetermined length of time.

14. The method of claim 13 in which the step of ejecting said log includes the steps of: closing a timed contact after said timing means has remained continuously activated for a predetermined length of time; activating a control means which is in series with said timed contact in response to closing of said contact; and ejecting said log in response to activation of said control means.

15. The method of claim 14 comprising: closing a control relay contact which is in parallel with said timed contact, and which is in series with said control means, in response to activation of said control means whereby said control means remains activated during ejection of a log; opening a normally closed limit switch which is in series with said timed contact and said control relay and in series with said control relay contact, at the time a log is completely ejected from said predetermined path.

16. The method of claim 1 in which logs are cut to a predetermined length before being conveyed along said predetermined path.

17. The method of claim 1 in which logs below a predetermined minimum diameter are conveyed directly to a subsequent processing means.

18. A method of sorting logs comprising: moving said logs along a predetermined path; establishing a plurality of ejection stations along said predetermined path at which logs might be ejected from said predetermined path; determining the presence of a log at said ejector station; determining the existence or nonexistence of a gap between adjacent logs being moved along said predetermined path; ejecting from said path at said ejec tion station those logs for which there is a gap between said log and the next adjacent log.

19. A log sorting apparatus comprising: conveying means for conveying logs or the like along a predetermined path; retaining means at either side of such path to prevent logs from deviating from said path; said retainer means on the first side of said path including a gap therein defining an ejection station, said gap being longer than the length of logs being conveyed on said conveying means; a yoke pivotally mounted above said path at said ejection station and having a first arm extending downwardly on said first side of said path and a second arm extending downwardly on the second side of said path; a retaining rail being operably connected to said first arm and having a length approximately the same as the length of said gap with said retaining rail thereby defining in conjunction with said retainer means a generally continuous retainer on said first side of said path; a kicker rail being operably connected to said second arm, said kicker rail being shorter in length than said retaining rail and having its lead end spaced downstream from' the lead end of said retaining rail; means for pivoting said yoke whereby said retaining rail moves out of said gap and said kicker rail ejects a log therethrough.

20. The log sorting apparatus of claim 19 in which: said retainer means on said second side of said path includes a gap therein generally opposite said gap in said first side; said gap being approximately the same in length as said kicker rail and said kicker rail normally being positioned within said gap to thereby form a generally continuous retainer in conjunction with said retainer means on said second side of said path.

21. The log sorting apparatus of claim 19 in which: said kicker rail includes a blocking means secured thereto at the lead edge thereof, said blocking means projecting in a direction laterally away from said conveying means whereby when said yoke is pivoted, said blocking means is moved into said predetermined path to thereby prevent logs from inadvertently passing behind the lead edge of said kicker rail.

22. The apparatus of claim 19 comprising: sensing means mounted adjacent said conveying means and adjacent said ejector station for determining the existence or nonexistence of a gap between adjacent logs traveling on said conveying means; activating means for pivoting said yoke only in response to the detection of a space between said adjacent logs by said gap sensing means 23. The log sorting apparatus of claim 22 in which said gap sensing means comprisesan ultrasonic beam directed across said predetermined path and a receiving means on the opposite side thereof.

24. The log sorting apparatus of claim 19 which comprises: minimum diameter sensing means for determining whether or not a log has a predetermined minimum diameter, at least at two points along the length thereof; activating means for activating. said yoke only in response to the sensing of a log having said predetermined minimum diameter at said ejector station.

25. The apparatus of claim 24 in which said sensing means comprises: means for projecting an energy transmitting beam diagonally and inwardly across said predetermined path generally at each end of said ejector station, said means at each end being spaced farther apart than the length of said retainer rail; a corresponding receiving means being positioned on the opposite side of said predetermined path for each said beam projecting means, said receiving means being positioned inwardly towards one another, closer together than the length of a log to be ejected from said ejector station.

26. The apparatus of claim 25 in which a vertical support is positioned on said first side of said predetermined path at the lead end of said retainer rail; a second vertical support being positioned at the second side of said predetermined path downstream of said first side vertical support, but upstream from the lead end of said kicker rail; said means for projecting an energy transmitting beam across said path being mounted on one of said vertical supports; said receiving means for receiving said energy transmitting beam being mounted on the other of said vertical supports.

connected to said sensing means and being activated in response to the sensing of a predetermined minimum diameter at a given point along the length of said log; said yoke being operably connected to said timing means and being pivoted thereby after said timing means remains continuously activated for a predetermined length of time.

43. The log sorting apparatus of claim 42 comprising: a timed contact being operably connected to said timing means and being closed in response to said timing means being continuously activated for said predetermined length of time; control means connected in series with said timed contact and being activated when said timed contact is closed; said control means being operably connected to said yoke for activating said yoke.

44. The apparatus of claim 43 comprising: a holding circuit in parallel with said timed contact, and in series with said control means; said control means comprising a control relay; said holding circuit including a first control relay contact operably connected to said control relay and being closed when said control relay is activated whereby said control relay remains closed even if a log is being removed from said conveying means; a normally closed limit switch in series with said timed contact, said holding circuit and said control relay; said limit switch being operably connected to said yoke such that when said yoke completes ejection of a log, said limit switch is opened, thereby deactivating said control relay and holding circuit and allowing said yoke to return to its normal position.

45. The apparatus of claim 39 in which means are provided at the lead end of said yoke for sensing the presence or absence of a gap between adjacent logs passing thereby; said activating means being activated only in response to the sensing of such a gap in combination with the sensing of a log having said predetermined minimum diameter.

46. The apparatus of claim 35 comprising: conveyor support means including a generally concave upper surface; said generally flat conveying means being flexible laterally inwardly whereby it tends to conform to the shape of said generally concave upper surface when loaded to thereby aid in locating the logs on said conveying means.

47. A log sorting apparatus comprising: conveying means for conveying logs endwise along a predetermined path; ejector means for ejecting logs from said conveying means; means adjacent said ejector means for sensing the presence of a log at said ejector means; means adjacent said ejector means for determining the existence of a gap between the ends of adjacent logs; activating means for activating said ejector means in response to sensing the presence of a log at said ejector means and in response to sensing a gap between the ends of adjacent logs.

48. The log sorting apparatus of claim 47 in which said gap sensing means comprises an ultrasonic beam directed across said predetermined path and a receiving means on the opposite side thereof.

49. The log sorting apparatus of claim 47 in which said means for sensing the presence of a log at said ejector means comprises: means for sensing whether the log has a predetermined minimum diameter, logs having a smaller minimum predetermined diameter being allowed to pass without said activating means activating said ejector means.

50. The apparatus of claim 49 in which said sensing means comprises: means for projecting an energy transmitting beam diagonally and inwardly across said predetermined path generally at each end of said ejector means, said means at each end being spaced farther apart than the length of said retainer rail; a corresponding receiving means being positioned on the opposite side of said predetermined path for each said beam projecting means said receiving means being positioned inwardly towards one another, closer together than the length of a log to be ejected from said ejector means.

51. The apparatus of claim 50in which a vertical support is positioned on said first side of said predetermined path at the lead end of said ejector means; a second vertical support being positioned at the second side of said predetermined path downstream of said first side vertical support; said means for projecting an energy transmitting beam across said path being mounted on one of said vertical supports; said receiving means for receiving said energy transmitting beam being mounted on the other of said vertical supports.

52.. The apparatus of claim 49 in which means are provided at the lead end of said ejector means for sensing the presence or absence of a gap between adjacent logs passing thereby; said activating means being activated only in response to the sensing of such a gap in combination with the sensing of a log having said predetermined minimum diameter.

53. A log sorting apparatus comprising: sorter conveying means for conveying logs along a predetermined sorting path; a plurality of ejector means positioned along said sorting path for ejecting logs from said sorter conveying means; a receiving bin positioned adjacent said sorter conveying means and adjacent said ejector means; a return conveyor means, adjacent said sorter conveying means, for conveying logs to a sawing apparatus; divertor means adjacent said sorter conveying means and adjacent each said receceiving bin for diverting logs ejected by said ejecting means from said receiving bin to said return conveying means; said divertor means being adjustable to a non-diverting position in which logs are ejected into said receiving bin.

54. The apparatus of claim 53 in which said sorter conveying means and said return conveying means comprise: a single continuous belt, the upper portion of said belt comprising said sorter conveying means and the portion of said belt passing beneath said upper portion comprising said return conveyor means.

55. The apparatus of claim 54 in which a track is positioned adjacent said sorter conveyor means and extends from said ejector means to said receiving bin; said divertor means comprising a portion of said track; said track portion being pivotable to a position blocking the path defined by said track, a second track extending from the pivotal mounting of said pivotable track portion to said return conveying means.

56. The log sorting apparatus of claim 53 in which said return conveying means is positioned directly below said sorter conveying means, said return conveying means traveling in a direction opposite to that of said sorter conveying means; said sorting apparatus including a live deck upon which logs are piled and from which logs are conveyed to saws; said live deck being positioned generally at the front end of said sorter conveying means; said return conveying means extending to a position generally above said live deck; ejector means being positioned adjacent said return conveying 27. The apparatus of claim 26 in which said projecting means and receiving means comprise an ultrasonic projector and receiver.

28. The log sorting apparatus of claim 19 which comprises: sensing means positioned along said conveying means for sensing at least the approximate diameter of a log at each point along the length thereof as said log passes by said sensing means; timing means operably connected to said sensing means and being activated in response to the sensing of a predetermined minimum diameter at a given point along the length of said log; said yoke being operably connected to said timing means and being pivoted thereby after said timing means remains continuously activated for a predetermined length of time.

29. The log sorting apparatus of claim 28 comprising: a timed contact being operably connected to said timing means and being closed in response to said timing means being continuously activated for said predetermined length of time; control means connected in series with said timed contact and being activated when said timed contact is closed; said control means being operably connected to said yoke for activating said yoke.

30. The apparatus of claim 29 comprising: a holding circuit in parallel with said timed contact, and in series with said control means; said control means comprising a control relay; said holding circuit including a first control relay contact operably connected to said control relay and being closed when said control relay is activated whereby said control relay remains closed even if a log is being removed from said conveying means; a normally closed limit switch in series with said timed contact, said holding circuit and said control relay; said limit switch being operably connected to said yoke such that when said yoke completes ejection of a log, said limit switch is opened, thereby deactivating said control relay and holding circuit and allowing said yoke to return to its normal position.

31. The apparatus of claim 24 in which means are provided at the lead end of said ejector station for sensing the presence or absence of a gap between adjacent logs passing thereby; said activating means being activated only in response to the sensing of such a gap in combination with the sensing of a log having said predetermined minimum diameter.

32. The apparatus of claim 19 comprising: a receiv-.

ing bin positioned adjacent said conveying means at said yoke; a return conveying means positioned adjacent said conveying means for conveying logs to a sawing apparatus; divertor means adjacent said converter means, between said yoke and said receiving bin for diverting logs ejected by said yoke from said receiving bin to said return conveying means; said divertor means being adjustable to a non-diverting position in which logs are ejected into said receiving bin.

33. The apparatus of claim 32 in which said conveying means and said return conveying means comprise: a single continuous belt, the upper portion of said belt comprising said conveying means and the portion of said belt passing beneath said upper portion comprising said return conveyor means.

34. The apparatus of claim 33 in which a track is positioned adjacent said conveyor means and extends from said yoke to said receiving bin; said divertor means comprising a portion of said track; said track portion being pivotable to a position blocking the path defined by said track, a second track extending from the pivotal mounting of said pivotable track portion to said return conveying means.

35. A log sorting apparatus comprising: a generally flat, continuous conveying means for conveying logs along a predetermined path; a yoke; pivotally mounted above said conveying means and opening downwardly towards said conveying means; the arms of said yoke being disposed one at either side of said conveying means whereby a log traveling on said conveying means is embraced by said yoke means; means for pivoting said yoke whereby a log passing therethrough is ejected from said conveying means.

36. The apparatus of claim 35 in which said means for pivoting said yoke is operable in only one direction whereby only one of said yoke arms comprises a kicker arm; said kicker arm including a blocking means secured thereto and projecting laterally away from said conveying means whereby when said yoke is pivoted, said blocking means is pivoted into the path being followed by logs on said conveying means.

37. The apparatus of claim 35 comprising: sensing means mounted adjacent said conveying means and adjacent said yoke for determining the existence or nonexistence of a gap between adjacent logs traveling on said conveying means; activating means for activating said pivoting means only in response to the detection of a gap between adjacent logs.

38. The log sorting apparatus of claim 37 in which said gap sensing means comprises an ultrasonic beam directed across said predetermined path and a receiving means on the opposite side thereof' 39. The log sorting apparatus of claim 35 which comprises: minimum diameter sensing means for determining whether or not a log has a predetermined minimum diameter, at least at two points along the length thereof; activating means for activating said pivoting means only in response to the sensing of a log having said predetermined minimum diameter at said ejector station.

40. The apparatus of claim 39 in which said sensing means comprises: means for projecting an energy transmitting beam diagonally and inwardly across said predetermined path generally at each end of said ejector station, said means at each end being spaced farther apart than the length of a log to be ejected, a corresponding receiving means being positioned on the op- 7 posite side of said predetermined path for each said beam projecting means, said receiving means being positioned inwardly towards one another, closer together than the length of a log to be ejected from said ejector station.

41. The apparatus of claim 40 in which a vertical support is positioned on said first side of said predetermined path at the lead end of said yoke; a second vertical support being positioned at the second side of said predetermined path downstream of said first side vertical support; said means for projecting an energy transmitting beam across said path being mounted on one of said vertical supports; said receiving means for receiving said energy transmitting beam being mounted on the other of said vertical supports.

42. The log sorting apparatus of claim 35 which comprises: sensing means positioned along said conveying means for sensing at least the approximatediameter of a log at each point along the length thereof as said log passes by said sensing means; timing means operably means and adjacent said live deck for ejecting logs off of said return conveying means and onto said live deck.

57. The apparatus of claim 56 in which said sorter conveying means and said return conveying means comprise: a single continuous belt, the upper portion of said belt comprising said sorter conveying means and the portion of said belt passing beneath said upper portion comprising said return conveyor means.

58. The apparatus of claim 57 in which a track is positioned adjacent said sorter conveyor means and extends from said ejector means to said receiving bin; said divertor means comprising a portion of said track; said track portion being pivotable to a position blocking the path defined by said track, a second track extending from the pivotal mounting of said pivotable track portion to said return conveying means.

59. A log sorting apparatus comprising: conveying means for conveying a log along a predetermined path; sensing means positioned along said path for sensing at least the approximate diameter of a log at each point along the length thereof as said log passes by said sensing means; ejector means positioned along said path for ejecting logs from said conveying means; timing means operably connected to said sensing means and being activated in response to the sensing of a predetermined minimum diameter at a given point along the length of said log; said ejector means being operably connected to said timing means and being activated thereby after said timing means remains continuously activated for a predetermined length of time.

60. The log sorting apparatus of claim 59 comprising: gap sensing means positioned along said path adjacent said ejector means at the upstream end thereof for determining the existence or non-existence of a gap between adjacent logs as they pass thereby; said gap sensing means being operably connected to said ejector means; said ejector means being activated in response to said timing means being continuously activated for said predetermined length of time and to said gap-sensing means simultaneously sensing a gap between adjacent logs.

61. The log sorting apparatus of claim 60 comprising: a first contact operably connected to said gap sensing means and being closed in response to sensing of a gap between adjacent logs; a timed contact in series with said first contact, said timed contact being operably connected to said timing means and being closed in response to said timing means being continuously activated for said predetermined length of time; control means connected in series with said first contact and said timed contact and being activated when said first contact and said timed contact are closed; said control means being operably connected to said ejector means for activating said ejector means.

62. The log sorting apparatus of claim 61 comprising: a holding circuit in parallel with said first contact and said timed contact, and in series with said control means; said control means comprising a control relay; said holding circuit including a first control relay contact operably connected to said control relay and being closed when said control relay is activated whereby said control relay remains closed even if gap sensing means senses the presence of a log after having first sensed a gap.

63. The log sorting apparatus of claim 62 comprising: a normally closed limit switch in series with said first contact, said timed contact, said holding circuit and said control relay; said limit switch being operably connected to said ejector means such that when said ejector means completes ejection of a log, said limit switch is opened, thereby deactivating said control relay and holding circuit and allowing said ejection means to return to its normal position.

64. The log sorting apparatus of claim 63 comprising: an ejector means activating circuit including a second control relay contact operably connected to said control relay and beingclosed in response to activation thereof; a solenoid in series with said second control relay contact; said ejector means being operably connected to said solenoid and being activated in response to activation of said solenoid.

65. The log sorting apparatus of claim 64 in which said approximate diameter sensing means comprises means for sensing the height of a log above said conveying means.

66. The log sensing apparatus of claim 65 in which said approximate diameter sensing means comprises an energy transmitting beam positioned at a predetermined height above said conveying means for transmitting an energy beam across said predetermined path, said timing means being activated in response to the breaking of said energy transmitting beam; said gap sensing means comprising means for projecting an energy transmitting beam across said predetermined path, said beam being broken by the passage of a log; said gap contact being closed when said gap sensing energy transmitting beam is unbroken.

67. The log sorting apparatus of claim 66 in which both of said energy transmitting beams are ultrasonic beams.

68. The log sorting apparatus of claim in which said approximate diameter sensing means comprises means for sensing the height of a log above said conveying means.

69. The log sensing apparatus of claim 68 in which said approximate diameter sensing means comprises an energy transmitting beam positioned at a predetermined height above said conveying means for transmitting an energy beam across said predetermined path, said timing means being activated in response to the breaking of said energy transmitting beam; said gap sensing means comprising means for projecting an energy transmitting beam across said predetermined path, said beam being broken by the passage of a log; said gap contact being closed when said gap sensing energy transmitting beam is unbroken.

70. The log sorting apparatus of claim 69 in which both of said energy transmitting beams are ultrasonic beams.

71. The log sorting apparatus of claim 59 in which said approximate diameter sensing means comprises means for sensing the height of a log above said conveying means. I

72. The log sorting apparatus of claim 71 in which said approximate diameter sensing means comprises means for projecting an energy transmitting beam across said path at a particular predetermined level above said conveying means and means for receiving said energy transmitting beams positioned on the other side of said predetermined path.

73. The log sorting apparatus of claim 72 in which said means for projecting said means for receiving said energy transmitting beam comprises means for projecting and means for receiving an ultrasonic beam.

74. The log sorting apparatus of claim 59 comprising: a timed contact being operably connected to said timing means and being closed in response to said timing means being continuously activated for said predetermined length of time; control means connected in series with said timed contact and being activated when said timed contact is closed; said control means being operably connected to said ejector means for activating said ejector means.

75. The log sorting apparatus of claim 74 comprising: a holding circuit in parallel with said timed contact, and in series with said control means; said control means comprising a control relay; said holding circuit including a first control relay contact operably connected to said control relay and being closed when said control relay is activated whereby said control relay remains closed even as a log is being removed from said conveying means.

76. The log sorting apparatus of claim 75 comprising: a normally closed limit switch in series with said timed contact, said holding circuit and said control relay; said limit switch being operably connected to said ejector means such that when said ejector means completes ejection of a log, said limit switch is opened, thereby deactivating said control relay and holding circuit and allowing said ejection means to return to its normal position.

77. The log sorting apparatus of claim 76 comprising:

an ejector means activating circuit including a second control relay contact operably connected to said control relay and being closed in response to activation thereof; a solenoid in series with said second control relay contact; said ejector means being operably connected to said solenoid and being activated in response to activation of said solenoid.

78. The log sorting apparatus of claim 77 in which said approximate diameter sensing means comprises means for sensing the height of a log above said conveying means.

79. The log sensing apparatus of claim 78 in which said'approximate diameter sensing means comprises an energy transmitting beam positioned at a predetermined height above said conveying means for transmitting an energy beam across said predetermined path, said timing means being activated in response to the breaking of said energy, transmitting beam; said gap sensing means comprising means for projecting an energy transmitting beam across said predetermined path, said beam being broken by the passage of a log; said gap contact being closed when said gap sensing energy transmitting beam is unbroken.

80. The log sorting apparatus of claim 79 in which both of said energy transmitting beams are ultrasonic beams.

81. A method for sorting logs comprising: conveying said logs along a predetermined path; sensing the approximate diameter of a log at each point along the length thereof as it passes a preselected point along said path; activating a timing means in response to the sensing of a predetermined minimum diameter at a given point along the length of said log; ejecting said log from said predetermined path after said timing means has remained continuously activated for a predetermined length of time.

82. The method of claim 81 which comprises the steps of: sensing the existence or non-existence of a gap between adjacent logs being moved along said predetermined path; ejecting said log from said predetermined path in response to said timing means having remained continuously activated for a predetermined length of time and to the simultaneous sensing of a gap between adjacent logs.

83. The method of claim 82 in which the step of ejecting said log includes the steps of: closing a first contact in response to the'sensing of a gap between adjacent logs; closing a timed contact which is in series with said first contact after said timing means has remained continuously activated for a predetermined length of time; activating a control means which is in series with said first contact and said timed contact in response to closing of said contacts; and ejecting said log in response to activation of said control means.

84. The method of claim 83 comprising: closing a control relay contact which is in parallel with said first contact and said timed contact, and which is in series with said control means, in response to activation of said control means whereby said control means remains activated even if said first contact is opened in response to the sensing of a log at a point where a gap had previously been sensed.

85. The method of claim 84 which comprises: opening a normally closed limit switch which is in series with said first contact, said timed contact and said control relay and in series with said control relay contact, at the time a log is completely ejected from said predetermined path.

86. The method of claim 81 in which the step of ejecting said log includes the steps of: closing a timed contact after said timing means has remained continuously activated for a predetermined length of time; activating a control means which is in series with said timed contact in response to closing of said contact; and ejecting said log in response to activation of said control means.

87. The method of claim 86 comprising: closing a control relay contact which is in parallel with said timed contact, and which is in series with said control means, in response to activation of said control means whereby said control means remains activated during the ejection of a log.

88. The method of claim 87 which comprises: opening a normally closed limit switch which is in series with said timed contact and said control relay and in series with said control relay contact, at the time a log is completely ejected from said predetermined path.

5%? UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION yawn; No. 3,815,738 nmd June 11, 197 4 Inventor(s) Harold J. Sweet, Robert L. Papworth, G John G. Grimm, Jr.

It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Assignee;

After "Herman" insert --Gundlach--;

Column 13, line 52;

"converter" should-be --conveyor--.

Signed and sealed this 29th day of October 1974;

(SEAL) Attest:

MCCOY M. GIBSON JR. C. MARSHALL DANN Attesting Officer Commissioner of Patents

Claims

1. A method for sorting logs comprising: moving said logs along a predetermined path; establishing a plurality of ejection stations along said path at which logs might be ejected from said path; scanning said logs at all points along the length thereof, at each said ejection station, to determine approximately the minimum diameter of a passing log; ejecting from said path, at each said ejection station, those logs having a predetermined minimum diameter, those logs having the largest minimum diameter being ejected at the first ejection station along said path with logs of progressively smaller minimum diameters being ejected at successive ejection stations.

2. A method for sorting logs comprising: moving said logs along a predetermined path; establishing a plurality of ejection stations along said path at which logs might be ejected from said path; scanning said logs at each said ejection station to determine approximately the minimum diameter of a passing log; ejecting from said path, at each said ejection station, those logs having a predetermined minimum diameter, those logs having the largest minimum diameter being ejected at the first ejection station along said path with logs of progressively smaller minimum diameters being ejected at successive ejection stations; determining whether or not there is a gap between adjacent logs when a given log is at a given ejection station; and ejecting a log at that ejection station only if such a gap is found to be present.

5. The method of claim 4 comprising: positioning one of a beam projector and beam receiver on one side of said path at each end of each ejection station, and at a distance apart which is greater than the length of a log to be ejected, whereby a log can be ejected therebetween; projecting a beam across said path, from or to said projector or receiver, in a diagonal inward direction towards the center of said ejection station whereby said beams are broken by a proper diameter log at the moment when they are in position to be ejected.

7. The method of claim 6 in which the step of ejecting said log includes the steps of: closing a first contact in response to the sensing of a gap between adjacent logs; closing a timed contact which is in series with said first contact after said timing means has remained continuously activated for a predetermined length of time; activating a control means which is in series with said first contact and said timed contact in response to closing of said contact; and ejecting said log in response to activation of said control means.

11. A method for sorting logs comprising: moving said logs along a predetermined path; establishing a plurality of ejection stations along said path at which logs might be ejected from said path; scanning said logs at each said ejection station to determine approximately the minimum diameter of a passing log; ejecting from said path, at each said ejection station, those logs having a predetermined minimum diameter, those logs having the largest minimum diameter being ejected at the first ejection station along said path with logs of progressively smaller minimum diameters being ejected at successive ejection stations; said minimum diameter of a passing log being determined by passing an ultrasonic beam across the path of said log at a predetermined height approximately at each end of a log in position at a given ejection station, the presence of a desired predetermined minimum diameter being indicated by blockage of both said beams by a log positioned therebetween.

18. A method of sorting logs comprising: moving said logs along a predetermined path; establishing a plurality of ejection stations along said predetermined path at which logs might be ejected from said predetermined path; determining the presence of a log at said ejector station; determining the existence or nonexistence of a gap between adjacent logs being moved along said predetermined path; ejecting from said path at said ejection station those logs for which there is a gap between said log and the next adjacent log.

19. A log sorting apparatus comprising: conveying means for conveying logs or the like along a predetermined path; retaining means at either side of such path to prevent logs from deviating from said path; said retainer means on the first side of said path including a gap therein defining an ejection station, said gap being longer than the length of logs being conveyed on said conveying means; a yoke pivotally mounted above said path at said ejection station and having a first arm extending downwardly on said first side of said path and a second arm extending downwardly on the second side of said path; a retaining rail being operably connected to said first arm and having a length approximately the same as the length of said gap with said retaining rail thereby defining in conjunction with said retainer means a generally continuous retainer on said first side of said path; a kicker rail being operably connected to said second arm, said kicker rail being shorter in length than said retaining rail and having its lead end spaced downstream from the lead end of said retaining rail; means for pivoting said yoke whereby said retaining rail moves out of said gap and said kicker rail ejects a log therethrough.

22. The apparatus of claim 19 comprising: sensing means mounted adjacent said conveying means and adjacent said ejector station for determining the existence or nonexistence of a gap between adjacent logs traveling on said conveying means; activating means for pivoting said yoke only in response to the detection of a space between said adjacent logs by said gap sensing means.

23. The log sorting apparatus of claim 22 in which said gap sensing means comprises an ultrasonic beam directed across said predetermined path and a receiving means on the opposite side thereof.

24. The log sorting apparatus of claim 19 which comprises: minimum diameter sensing means for determining whether or not a log has a predetermined minimum diameter, at least at two points along the length thereof; activating means for activating said yoke only in response to the sensing of a log having said predetermined minimum diameter at said ejector station.

27. The apparatus of claim 26 in which said projecting means and receiving means comprise an ultrasonic projector and receiver.

32. The apparatus of claim 19 comprising: a receiving bin positioned adjacent said conveying means at said yoke; a return conveying means positioned adjacent said conveying means for conveying logs to a sawing apparatus; divertor means adjacent said converter means, between said yoke and said receiving bin for diverting logs ejected by said yoke from said receiving bin to said return conveying means; said divertor means being adjustable to a non-diverting position in which logs are ejected into said receiving bin.

38. The log sorting apparatus of claim 37 in which said gap sensing means comprises an ultrasonic beam directed across said predetermined path and a receiving means on the opposite side thereof.

39. The log sorting apparatus of claim 35 which comprises: minimum diameter sensing means for determining whether or not a log has a predetermined minimum diameter, at least at two points along the length thereof; activating means for activating saId pivoting means only in response to the sensing of a log having said predetermined minimum diameter at said ejector station.

40. The apparatus of claim 39 in which said sensing means comprises: means for projecting an energy transmitting beam diagonally and inwardly across said predetermined path generally at each end of said ejector station, said means at each end being spaced farther apart than the length of a log to be ejected, a corresponding receiving means being positioned on the opposite side of said predetermined path for each said beam projecting means, said receiving means being positioned inwardly towards one another, closer together than the length of a log to be ejected from said ejector station.

42. The log sorting apparatus of claim 35 which comprises: sensing means positioned along said conveying means for sensing at least the approximate diameter of a log at each point along the length thereof as said log passes by said sensing means; timing means operably connected to said sensing means and being activated in response to the sensing of a predetermined minimum diameter at a given point along the length of said log; said yoke being operably connected to said timing means and being pivoted thereby after said timing means remains continuously activated for a predetermined length of time.

51. The apparatus of claim 50 in which a vertical support is positioned on said first side of said predetermined path at the lead end of said ejector means; a second vertical support being positioned at the second side of said predetermined path downstream of said first side vertical support; said means for projecting an energy transmitting beam across said path being mounted on one of said vertical supports; said receiving means for receiving said energy transmitting beam being mounted on the other of said vertical supports.

52. The apparatus of claim 49 in which means are provided at the lead end of said ejector means for sensing the presence or absence of a gap between adjacent logs passing thereby; said activating means being activated only in response to the sensing of such a gap in combination with the sensing of a log having said predetermined minimum diameter.

56. The log sorting apparatus of claim 53 in which said return conveying means is positioned directly below said sorter conveying means, said return conveying means traveling in a direction opposite to that of said sorter conveying means; said sorting apparatus inclUding a live deck upon which logs are piled and from which logs are conveyed to saws; said live deck being positioned generally at the front end of said sorter conveying means; said return conveying means extending to a position generally above said live deck; ejector means being positioned adjacent said return conveying means and adjacent said live deck for ejecting logs off of said return conveying means and onto said live deck.

60. The log sorting apparatus of claim 59 comprising: gap sensing means positioned along said path adjacent said ejector means at the upstream end thereof for determining the existence or non-existence of a gap between adjacent logs as they pass thereby; said gap sensing means being operably connected to said ejector means; said ejector means being activated in response to said timing means being continuously activated for said predetermined length of time and to said gap sensing means simultaneously sensing a gap between adjacent logs.

64. The log sorting apparatus of claim 63 comprising: an ejector means activating circuit including a second control relay contact operably connected to said control relay and being closed in response to activation thereof; a solenoid in series with said second control relay contact; said ejector means being operably connected to said solenoid and being activated in response to activation of said solenoid.

68. The log sorting apparatus of claim 60 in which said approximate diameter sensing means comprises means for sensing the height of a log above said conveying means.

71. The log sorting apparatus of claim 59 in which said approximate diameter sensing means comprises means for sensing the height of a log above said conveying means.

77. The log sorting apparatus of claim 76 comprising: an ejector means activating circuit including a second control relay contact operably connected to said control relay and being closed in response to activation thereof; a solenoid in series with said second control relay contact; said ejector means being operably connected to said solenoid and being activated in response to activation of said solenoid.

79. The log sensing apparatus of claim 78 in which said approximate diameter sensing means comprises an energy transmitting beam positioned at a predetermined height above said conveying means for transmitting an energy beam across said predetermined path, said timing means being activated in response to the breaking of said energy transmitting beam; said gap sensing means comprising means for projecting an energy transmitting beam across said predetermined path, said beam being broken by the passage of a log; said gap contact being closed when said gap sensing energy transmitting beam is unbroken.

83. The method of claim 82 in which the step of ejecting said log includes the steps of: closing a first contact in response to the sensing of a gap between adjacent logs; closing a timed contact which is in series with said first contact after said timing means has remained continuously activated for a predetermined length of time; activating a control means which is in series with said first contact and said timed contact in response to closing of said contacts; and ejecting said log in response to activation of said control means.