US3168094A

US3168094A - Traction therapy apparatus

Info

Publication number: US3168094A
Application number: US121769A
Authority: US
Inventors: Robert W Siltamaki
Original assignee: TRU EZE Manufacturing CO Inc
Current assignee: TRU EZE Manufacturing CO Inc
Priority date: 1961-07-03
Filing date: 1961-07-03
Publication date: 1965-02-02
Anticipated expiration: 1982-02-02

Description

Feb. 2, 1965 R. w. slLTAMAKl TRACTION THERAPY APPARATUS Filed July 3. 1961 3 Sheets-Sheet l yall] Feb. 2, 1965 R. w. slLTAMAKl 3,168,094

TRACTION THERAPY APPARATUS Filed July 5. 1961 5 Sheets-Sheet 2 Feb. 2, 1965 R. w. slLTAMAKl 3,168,094

TRACTION THERAPY APPARATUS Filed July 5. 1961 3 Sheets-Sheet 3 United States Patent O MME-'4 TRACTIUN THERAPY APPARATUS Robert W. Siltamalri, Burbank, Calif., assigner, by mesne assignments, to Tru-Eze Mfg. Co., inc., Burbank, Salif., a corporation of California Filed hilf] 3, 1961, Ser. No. 121,769 i7 iaims. (Ci. 12S-75) This invention relates to therapeutic apparatus and more particularly to a means for imparting intermittent traction to a patient; such apparatus being more commonly employed -for imparting traction to the spinal columns of patients but being useful for any therapy in which intermittent traction is indicated.

In the treatment of injuries or disease conditions for which the use of traction is desirable, the most beneficial amount of tractive force is often greater than the level of tolerance of the patient for the continued application of such tractive force. A patient may, however, be subjected to momentarily applied tractive forces which are much greater than those which may be applied continuously and therefore, by the use of intermittent traction, the amount of tractive force which is `most beneficial to the condition being treated can be achieved without undue discomfort to the patient.

The principal object of the invention is to provide an organized apparatus for applying intermittent traction to a patient in which not only the length of elapsed time for a total treatment can be predetermined but also the factors of the frequency of the application of tractive efforts, the time periods of maximum traction lapplication and the amount `of tractive effort or pull are independently adjustable by an attendant either before or during a treatment.

Another object of the invention is to provide a traction therapy apparatus `of the `above `character in which the apparatus automatically adapts itself to the position of the patient relative to the apparatus in the line of traction effort.

Still another object of the invention is to provide an intermittent traction applying apparatus in which the attainment of a predetermined maximum pull or tractive effort is the factor lwhich initiates a cycle of operation comprising an adjustably predetermined holding or dwell at the maximum tractive effort condition, a release of the tension, a second dwell separately adjustable as to the time interval thereof at the end of the tension releasing movement, and another application or pull of tension on the portion of the body of the patient subjected to treatment until the attainment of the said predetermined maximum pull or traction initiates the next cycle of operation.

A still further object of the invention is to provide an intermittent traction producing apparatus of the above character -which is susceptible of use on a patient in either a seated position or in a prone or supine position.

Still another object of the inven-tion is to provide an intermittent traction producing apparatus which is o-f small size and readily transportable and which may be readily installed for use and as readily dismounted after use.

A still further object of the invention is to provide an intermittent traction therapy 4apparatus which is simple and sturdy in construction, which is quickly adapted for use with succeeding patients and which is capable of long 4and continued use Awithout the need for servicing.

With the foregoing objects in view, together with such additional objects and advantages las may subsequently appear, the invention resides in the parts and in the construction, combination and arrangement of parts described, by way of example, in the following specification of a presently preferred embodiment of the invention;

iddli Patented Feb. 2, 1965 reference being had to the accompanying `dra-wings which form a part of said specification and in which drawings:

FIG. l is a front View of ya traction therapy apparatus embodying the present invention; the view being capable of being construed as applied to the head of a patient and being either mounted `on a wall for treatment of a seated patient or on a table or the like for treatment of a patient lying on a bed or table,

FIG. 2 is a side elevational View as viewed from the right hand side of FIGA,

FIG. 3 can be construed either as a top plan -view or a rear elevational view depending whether the apparatus is considered as being mounted on a vertical surface or a horizontal surface,

FIGS. 4 and 5 show in reduced scale the means for detachably mounting the apparatus on a surface (horizontal or vertical) for use,

FIG. 6 is an enlarged scale sectional view taken on line 6 6 of FIG. l,

FIG. 7 is an enlarged scale sectional View taken on the line 7 7 of FIG. 2,

FIG. S is a rear view of the timer panel of the apparatus,

FIG. 9 is a fragmentary sectional view taken on the line 9 9 of FIG. 6,

lFIG. l0 is a fragmentary View generally similar to FIG. 6 but showing the relation of the cycle initiating components at the instant of achieving a predetermined maximum amount of traction, and during the hold period,

FIG. ll is an enlarged scale sectional View taken on the line 11.-11 of FIG. 2,

|FIGS. l2 and 13 are fragmentary, sectional views taken on the llines 12-12 and 13a-A13, respectively, of FIG. 6,

FlG. 14 is a fragmentary sectional View taken on the line f4-14 of FIG. l, and

FIG. l5 is a circuit diagram of the electrical system of the apparatus.

Referring to the drawings, the illustrated embodiment of the invention comprises a supporting frame structure 1 including a frame casting Z of modified U-shape configuration disposed with the open end thereof extending laterally toward the base of the device; said casting having a vertical plate 3 attached to and covering one side thereof :and said plate including a depending portion 4 to which a driving motor means 5 is mounted and to which further reference will hereinafter be made. The opposite side of the casting 2 extends in a plane parallel to the .iirst mentioned side and carries a side plate 6 and a removable, access plate 7. i'I'he `frame structure further includes a base member S here shown `as a heavy sheet metal pan of rectangular configuration and including side flanges 9 and 9' and top and bottom llanges it) and 1li and the upper arm 11 of the frame casting 2 is secured to the top flange lIii at the midlength thereof by a bolt d2. The vertical dimension of said base member is considerably greater than the vertical dimension of the frame structure 41 `and the llower arm 13 -of the :casting 2 terminates in an upwardly extending foot portion 14 and a screw 15 extends through a mounting member 16 t0 which detailed reference will later be made, then through the bottom 117 of the base member 8 and threadedly engages said 'foot portion d4 to secure the frame structure and base member together with the frame structure 1 extending at right angles from the plane of the base member bottom 17.

A sheet metal cover 18 has the skirt portion thereof secured to the outer faces of the

base member flanges

9, 9', 10 and liti by screws 19; said cover member projecting forwardly a lesser distance than said frame structure and having a slot Ztl formed in the upper portion of the front face 21 thereof and in the top side face 22 thereof through which the frame structure 1 projects forwardly beyond said front face 21. Preferably, the upper portion 23 of said front face 21 of the cover is outwardly, convexly curved and the portion 24 thereof below the frame structure 1 extends diagonally downwardly and rearwardly and is provided with a rectangular opening 25 over which an instrument panel 26 is secured by screws 27.

The motor means is secured by

bolts

28, 28 to one side of the depending portion 4 of the plate 3 and is spaced therefrom by

bosses

29, 29 on the motor means. The said motor means is reversible and comprises, in effect, two separate motors having the armatures thereof mounted on and xed to the horizontal motor shaft 30; said motors including a rst motor 31 operable only to effect rotation of the motor shaft in a direction to effect traction on a patient by devices actuated thereby which will presently be described, and a second motor 32 operable only to etfect rotation of the motor shaft 38 in the opposite direction. This opposite rotation requires less effort and, accordingly the motor 32 is less powerful than the motor 31 and the armature associated therewith. Also comprising a part of the motor means 5 is a speed reduction unit 33 comprising a gear housing into which one end of the motor shaft St) extends and which contains suitable gearing between the motor shaft 3) and the horizontal Ydriven shaft 34- which projects therefrom and thence through the plate portion 4. At the side of said plate portion 4 opposite the motor means 5, the shaft 34 carries a small sprocket 35 which is connected by a sprocket chain 36 to a larger sprocket 37 fixed by a key 37 to a shaft 38; said shaft being journaled in

bushings

39, 39 carried by the plates 3 and 6 as best shown in FIG. 7. Mounted on the shaft 38 between the plates 3 and 6 is a windlass pulley 40 xed to the shaft by a key 40' and a collar 41 iixed to the shaft 38 exteriorly of the plate 6 cooperates with the sprocket 37 to prevent endwise movement of the shaft 38.

The windlass pulley 40 is provided with a cylindrical body portion 42 bordered by

flanges

43, 43 and the said tbody portion 42 is provided with a hole 44 extending tangentially therethrough in which one end of a flexible member such as a cable 45 is clamped by a screw 46 extending parallel to and laterally spaced from the shaft 38 (see FIG. 7). The cable 45 is thence wrapped sever-a1 turns about the body portion 42 in a counterclockwise direction `as viewed in FIG. 6 and thence extends from the top of the windlass pulley substantially horizontally forward over a rst grooved idler sheave 47 mounted for free rotation on a bolt 48 xed to a lever larm 49 which lever arm is pivotally mounted on a sleeve 5t) clamped to the inner face of the plate 3 by a bolt 51 and disposed adjacent the lower portion of said plate; said sleeve having an enlarged flange portion 52 holding the arm 49 in laterally spaced relation to the inner face of the plate 3. On the side of the lever arm 49 opposite the plate 3, the sleeve 50 carries a second grooved idler sheave 53 over which the cable 45.i s next trained and from which it thence extends downwardly through an opening 54 in the forward or outer end of the bottom run 13 of the frame member 1; the distal end of said cable being attachable to suitable devices connecting it to the patient as, for example, the head strap means H. Preferably, the bolt 51 carries a guard member 55 extending over the portion of the sheave over which the cable 45 passes to prevent the cable from getting out of the groove in the sheave. As the motor means 5 is actuated to rotate the windlass pulley 40 in a clockwise direction as viewed in FIGS. 6 and 10, the cable will be wound thereon 'to produce traction on the patient to which the cable is effect is discontinued.

The device may be mounted on a wall W or the like for vtreatment of a seated patient and it is in relation to that most common mode of use that the terms upper,

lower, forward, horizontal, vertical, etc. have been dwell period occurs.

employed. The device may, however, be mounted on a table or the like for treatment of a patient lying on a bed or table. The illustrated mounting means 16 comprises la metal ange having downwardly converging

edges

56, 56 spaced outwardly from the rear or mounting surface of the device and adapted to detachably engage complementary slots 56', 56' in a socket member 57 fixed to the wall or other surface on which the device is to be mounted. Preferably, the lower or rear surface of base member 8 is provided with a resilient pad 58 to cushion the device against the mounting surface.

Control means The means by which the device applies successive traction efforts of adjustable predetermined magnitude, duration, and frequency land of predetermined extents of treatment comprises an electro-mechanical system operated by alternating current which system will now be described. The end of the lever arm 49 remote from the pivotal mounting thereof is provided with a depending cylindrical boss 59 which is engaged by one end of the compression spring 69 which thus bears against the shoulder formed by said boss. The other end of the spring surrounds Ia corresponding boss 61 on the inner surface of the run 13 of the frame member 1 and bears against the said inner face of said member; the effort of said spring being to urge the lever arm in a counterclockwise direction about its pivotal mounting as viewed in FIGS. 6 and 10. As the windlass pulley winds in the cable 45 creating tension on the cable from the resistance offered by the patient, the reaction of the cable is to tend to straighten the bight thereof extending between the pulley 40 and the sheave 53 by causing the sheave 47 and lever larm 49 to move in a clockwise direction as viewed in FIGS. 6 and 10 against the resistance offered by the spring 60. As will be presently explained, it is the pivotal movement of the lever arm 49 in response to the changing biases imposed thereon by the tension on the cable 45 and the yielding resistance of the spring 60 that eects the cycle of operation of the device.

Before going into a detailed description of the electrical system, .the cycle of operation will be briefly described.

Assuming that the cable 45 is attached to a patient and the machine placed in operation the motor 31 of the motor means 5 is automatically energized to wind up the cable 45 and when the traction eected by the cable reaches a predetermined maximum value, the motor means 5 is stopped and held against reverse rotation for a predetermined time at that maximum traction value. At the end of that dwell time, the bias Iis removed from the motor 31 and the motor means 32 is energized to reverse the rotation of the windlass pulley and relieve the tension on the cable 45. When the cable reaches slack condition, the motor 32 is stopped and a second At the end off that second dwell period, the motor 31 is re-energized to start a new cycle. All of the foregoing steps take place in sequence automatically and the treatment continues for the time set on the master time switch of the device. When this time expires, the device continues to operate through control means to be described until the cycle which may have been in progress at t-he instant o-f expiration of time by the master switch has been completed.

The control means includes an adjustable sto-p means for determining the maximum amount of traction to be exerted on an individual patient at each cycle of operation of the device; said means including a shaft 62 journaled in and extending between the plates 3 and 7; said shaft being disposed below the lever arm 49. The shaft extends beyond the outer surfaces of the plates 3 and 7 and at each end thereof carries one each of a pair of 'hand knobs 63, 63 each of which has a radial indexed 'line 64 which registers along a semicircular scale or dial 65 to indicate the extent or magnitude of maximum traction effort to be exerted. Fixed to the shaft 62 and exslashes tending between the plates 3 and 7 is an eccentric member 62' to wh-ich further reference will presently be made.

The total elapsed time for a treatment is determined by a master time switch means 66 including a single throw switch 66 operated by clock work to be closed when the clock work is started at the beginning of a period and to open when the said period reaches zero; said switch eing mounted on the panel E6 and being adjusted by a handle 6'7 moved with reference to a dial 68 on the exterior of the panel 26.

The length of the dwell which occurs at the time of maximum traction effort, hereinafter called the holding dwell, is determined by an automatically re-set timing device 69 which operates a double throw switch means 69 forming a part thereof and which is held normally in one of its two set positions. The timing device 69 is mounted on the inner face of the panel Z6 and has an operating hand knob 70 exteriorly of Athe panel provided with index means having reference to an associated dial 71.

The elapsed time for the dwell at the end of traction release, hereinafter called the rest dwell, is determined by a timing device '72 which is identical to the device 69 and which likewise includes a corresponding double throw switch means '72' which is normally held in one of its two positions. The :timing device '72 is also mounted on the inner face of the panel 26 and is provided with an Operating hand knob '73 which similarly has means for indexing reference to a dial 7d. All of the foregoing timing devices are standard components, wherefore, urther description is deemed unnecessary.

Mounted on and movable with the lever arm i9 is a double throw snap switch 75 which moves from one to the other of its two positions in response to movement of the lever arm 49. The distal end of the lever arm 49 also carries a normally closed single throw switch '76 whose primary function is to insure that upon the end of a treatment period the device will continue to operate until the end of the cycle during which the treatment time determined by the master timer 66 expired.

FIG. l5 shows the relative positions o the electrical system components prior to beginning treatment of a patient. Assuming that the device is both connected to a patient and to a source of alternating current and that adjustment has been made yfor the desired magnitude of traction as well as the length of the respective dwell periods, the master timer knob 67 is turned to set the length of time for the treatment. This closes the switch 66' allowing power to iiow through the lead '755, switch 66', and lead '79 to the common terminal of the switch '75; said switch being in the full line position and thus causing current to flow through the lead Sti to the timing means and switch actuator of the rest timer '72 causing it to go through its previously predetermined dwell period and then move the switch 72' to the dotted line position; the circuit being completed through the lead @l to the power lead 82. This dotted line position of the switch '72' completes the power circuit for operating the motor 3l which circuit extends `from the switch 66' through lead 83 to the switch 69', the lead 84 to the switch 'i2' and thence through leads 85 and 86 to and from the motor means 31 to the power lead 82. The circuit remains until the switch 75 is moved to its other position.

As the cable 45 is wound on the pulley d@ and achieves tension by the resistance offered by the body of the patient, the lever arm 49 will be moved about its pivotal mounting against the resistance of the spring 6i?. The switch 75 has a iirst operating plunger projecting from one side of the switch case which is engaged by the arm 88 or" a lever 89 pivotally mounted in a bracket 9i) on the switch case; said switch in its full line position normally causing the plunger to protrude to the extent shown in FlG. 6 and the lever 89 having a stop member 91 engageable with the switch case to limit the extent of movement of the lever 89 in a counterclockwise direction as viewed in FIGS. 6 and l0. The switch '75 extends at right angles to the axes of the shaft 62 and eccentric 62' and the movement of the lever arm di? in response to cable tension brings the lever 89 against the eccentric 62'; the distance the lever arm may thus be required to move to effect this contact with the eccentric with consequent greater or lesser compression of the spring d@ being dependent on the adjusted position of the eccentric 62.

As the tension on the cabie 45 causes the lever arm 49 to engage the eccentric 62', as shown in FIG. l0, the switch '75 snaps to its dotted line position, whereupon, current from the lead 79 then tlows through the lead 93 to the timing means and switch actuator of the holding timer 69 causing it to go through its previously predetermined dwell period and then move the switch 69' to its dotted line position; the circuit being completed through leads 9d and S?. to the power lead 32. This also completes the power circuit for the motor 32 through lead 95, and the motor 32 reverses the direction of rotation of the windlass pulley 49 until the slackening of the cable 4S allows the spring 6% to move the lever arm 49 to a position in which the plunger 96 of the switch 7 S is actuated by engagement with an actuating resilient leaf element 97 carried by the arm d@ with an adjustable stop means comprising an eccentric 98 carried by a screw 99 for rotative adjustment on the inner face of the plate 3, said engagement with the plunger 96 causing the switch 75 to snap back to its full line position. This starts the next cycle of operation of the device with the institution of the dwell of the rest timer 72 as previously described and the cycles of operation repeat themselves until the time set by the master timer 66 has expired.

It is desirable in some instances, that the motor means be held against rotation when operating current is not supplied to either motor component and that the motor be stopped instantly upon cessation of current supply to either motor component thereof. For this purpose, a rectiying means Mit) comprising a diode 101 and a resistor 162 may be interposed between leads T03 and 1M extending, respectively, to the lead 84 and to the side of the switch 72' which is connected to the lead SS when that switch is in its full line position. Additionally, the rectifying means may include a capacitor N5 connected 'to the lead 82 by a lead 10d. It will be noted that at all times when the switch 66' is closed and the switches 69' and '72' are in their full line positions, only one phase of the alternating current is being imposed on the alternating current motor 3l thus holding it against rotation.

There remains to be described the function of the switch 76. This switch is normally closed at all times except when the lever arm 49 is at its extreme upper position as shown in FIG. 6. At this time the distal end of the resilient leaf 97 contacts an operating lever 167 pivotally mounted at 16S on the case of switch 76; said lever operating a plunger N9 of the switch to open the switch contacts. At all other times, this switch is closed and therefore, if the switch 66' should be opened while a cycle of operation is in progress, current will nevertheless flow between the leads 78 and 79 through the closed switch 76 until the lever arm reaches the slack cable position shown in FIG. 6 with resultant opening of this switch. The switch 76 thus insures that regardless of when elapsed time determined by the timer 6e expires, the device will nevertheless complete the cycle then in progress.

if, for any reason, Athe switch means for stopping the motor 32 should fail to operate and the continued operation of that motor would first completely unwind the cable and then start to wind it up in the reverse direction, the cable would be drawn down over the distal end of the resilient ieaf 97 causing it to move the switch from its dotted line to full line position and to restart the cycle of operation. This insures that the cycle will be repeated under all circumstances.

While in the foregoing specification, there has been disclosed a presently preferred embodiment of the invention, the invention is not to be deemed to be limited to the exact and precise details of construction thus shown by way of example and it will be understood that the invention includes as well, all such changes and modifications in the parts, .and in the construction, combination and arrangement of parts as shall come Within the purview of the appended claims.

I claim:

1. In a device foi subjecting a patient to repeated applications of traction, a windlass means, a flexible member having one end thereof attached to said windlass means and having its other end provided with means for attachment to the portion of the body of the patient to be subjected to traction, reversible motor means for actuating said windlass means in alternate directions with resultant winding in and unwinding of said flexible member and consequent application and relief of traction on the patient, and control means for reversing said motorV means operable automatically when winding in of said flexible member shall have effected a traction pull of predetermined magnitude on a patient, to reverse said motor means with resultant unwinding of said flexible member; said control means including a time delay switch and means operated thereby operative to stop said motor means upon reaching said predetermined magnitude of traction for a predetermined time interval before said motor means is reversed to relieve said traction.

2. A therapeutic traction applying device as claimed in claim l which further includes a second time delay switch means operable to institute traction producing winding in of said flexible member and consequent application of traction to a patient at the end of a predeter- `mined time interval after unwinding of said flexible member has reduced the magnitude of traction on said flexible member to zero.

3. A therapeutic traction applying device as claimed in claim 2 which further includes an elapsed time switch which is adjustable to determine the total elapsed time for a treatment and which further includes devices which effect stoppage of said device at a point in its cycle of operation which is immediately prior to the beginning of exertion of a traction effort.

4. In a device for subjecting a patient to repeated applications of traction, a windlass means, a flexible member having one end thereof attached to said windlass means and having its other end provided with means for attachment to the portion of the body of the patient to be subjected to traction, reversible motor means for actuating said windlass means in alternate directions with resultant Winding in and unwinding of said flexible member and consequent application and relief of traction on the patient, and control means for reversing said motor means operable automatically when Winding in of said flexible member shall have effected a traction pull of predetermined magnitude on a patient, to reverse said motor means with resultant unwinding of said flexible member; said control means including a time delay switch and means operated thereby operative successively to stop said motor means upon reaching said predetermined magnitude, to hold said motor means against reverse action incident to traction pull on said flexible member and finally to reverse the direction of rotation of said motor means to relieve said traction on said flexible member.

5. In a device for subjecting a patient to repeated applications of traction, a windlass means, a flexible member having one end thereof attached to said windlass means and having its other end provided with means for attachment to the portion of the body of the patient to be subjected to traction, reversible motor means for actuating said windlass means in alternate directions with resultant winding in and unwinding of said flexible member and consequent application and relief of traction on the patient, and control means for said reversible motor means including an electric switch and spring bias operating means engaging said switch including devices engaging said flexible member and tending to yieldingly laterally displace said flexible member whereby in response to imposition of a traction pull on said flexible member of a predetermined magnitude, said flexible member engaging devices will be moved against the spring bias thereon with resultant actuation of said switch to effect reversal of said motor means and consequent unwinding of said windlass means.

6. A therapeutic traction applying device as claimed in claim 5 which includes manually adjustable means for determining the magnitude of traction effort imposed on said flexible member required to effect reversal of said motor means by actuation of said spring biased switch operating means.

7. A therapeutic traction applying device as claimed in claim 5 in which said control means for said motor means includes devices actuated by the spring bias on said switch operating means when the tension on said flexible member decreases to Zero to change the direction of rotation of said motor means to institute winding up of said flexible member by said windlass means.

8. In a device for subjecting a patient to repeated applications of traction, a windlass means, a flexible member having one end thereof attached to said windlass means and having its other end'provided with means for attachment to the portion of the body of the patient to be subjected to traction, reversible motor means for actuating said windlass means in alternate directions with resultant winding in and unwinding of said flexible member and consequent application and relief of traction on the patient, and control means for reversing said motor means operable automatically when winding in of said flexible member shall have effected a traction pull of predetermined magnitude on a patient, to reverse said motor means with resultant unwinding of said flexible member; said control means further including an elapsed time switch which is adjustable to determine the total time for a treatment and additionally includes devices operable to effect stoppage of said traction applying device ata point in its cycle of operations which is immediately prior to the beginning of a traction effort thereby.

9. In a device for subjecting a patient to repeated applications of traction, a windlass means, a flexible member having one end thereof attached to said windlass means and having its other end provided with means for attachment to the portion of the body of the patient to be subjected to traction, reversible motor means for actuating said windlass means in alternate directions with resultant winding in and unwinding of said flexible member and consequent application and relief of traction on the patient, and control means for reversing said motor means operable automatically when winding in of said flexible member shall have effected a traction pull of predetermined magnitude on a patient, to reverse said motor means with resultant unwinding of said flexible member;

said control means further including a time delay switch means operable to institute winding in of said flexible Vmember and consequent application of traction to a patient at the end of :a predetermined time interval after the previous unwinding of said flexible member has reduced the magnitude of traction to zero.

10. In a therapeutic device for subjecting a patient to repeated applications of traction, a base, a rigid arm structure projecting from one surface of said base, a windlass pulley, mounting means for said windlass pulley, and reversible motor means for actuating said windlass pulley disposed at the end 'of said arm which is adjacent to said base, a guide means at the distal end of said arm, a flexible member having one end thereof fixed to said windlass pulley and thence being trained over said guide means to its other end, means at said other end of said flexible member for attachment thereof to the portion of the body of a patient to be treated, control devices for said motor 9 means operable to cause said motormeans to alternately rotate said windlass means in opposite directions with consequent Winding and unwinding of said flexible member thereon, and devices responsive to the amount of tension lon said flexible member incident to a traction effort thereby effective upon attainment of a predetermined maximum magnitude of tension to reverse the direction of rotation of said motor means.

11. A therapeutic traction applying device as claimed in claim in which said control devices include a pulley engaging and laterally displacing said flexible member intermediate said windlass pulley and said guide means, a spring biased mounting for said pulley yieldingly tending to effect lateral displacement of the flexible member at the point of engagement by said pulley, and switch means actuated by movement of said pulley mounting means incident to movement thereof deriving from tension on said flexible member sufficient to overcome said spring bias and operative to cause reversal of said motor means and release of tension on said flexible member.

12. A therapeutic traction applying device as claimed in claim 10 in which said control means includes a time delay switch and means operated thereby operative to stop said motor means upon reaching said predetermined magnitude of tension on said flexible member for a predetermined time interval before reversing said motor means to relieve said tension on said flexible member.

13. A therapeutic traction applying device as claimed in claim 10 which includes means associated with said pulley mounting means for adjustably predetermining the magnitude of traction eflort required to actuate said control means to effect reversal of said motor means and said pulley.

14. A therapeutic traction applying device as claimed in claim 10 in which said control means for said motor means includes means vfor reversing the direction of rotation of said motor means to institute winding up of said flexible member by said windlass pulley after the tension on said flexible member has been reduced to zero.

15. A therapeutic traction applying device as claimed in claim 10 in which said control means includes an elapsed time switch which is adjustable to predetermine the total time for a treatment and which further includes devices operable automatically to eflect stoppage of said device at a point in its cycle of operation which is substantially at the time the tension on said flexible member has been reduced to zero.

16. A therapeutic traction applying device as claimed in claim 10 in which said control means further includes a time delay switch means operable to institute traction producing Winding in of said flexible member and consequent application of traction to a patient at a predetermined time interval after unwinding of said flexible member has reduced the magnitude of traction to zero.

17. A therapeutic traction applying device as claimed in claim 1l in which said control means further includes a time delay switch means operable to institute traction producing Winding in of said flexible member and consequent application of traction to a patient at the end of a predetermined time interval after unwinding of said flexible member has reduced the magnitude of traction to zero.

References Cited by the Examiner UNITED STATES PATENTS 2,275,953 3/42 Frisch 254--172 2,468,092 4/49 Mahnke 254-173 2,474,267 6/ 49 Mahnke 254-173 2,512,017 6/50 Hayes 254-173 2,773,499 12/56 Zur Nieden 12S-75 2,811,965 11/57 Richards 128-75 2,861,565 11/58 LaPierre 128-71 2,910,061 10/59 Rabjohn 128-70 2,958,510 11/60 Finch 254--173 RICHARD A. GAUDET, Primary Examiner.

ROBERT E. MORGAN, Examiner.

Claims

5. IN A DEVICE FOR SUBJECTING A PATIENT TO REPEATED APPLICATIONS OF TRACTION, A WINDLASS MEANS, A FLEXIBLE MEMBER HAVING ONE THEREOF ATTACHED TO SAID WINDLASS MEANS AND HAVING ITS OTHER END PROVIDED WITH MEANS FOR ATTACHMENT TO THE PORTION OF THE BODY OF THE PATIENT TO BE SUBJECTED TO TRACTION, REVERSIBLE MOTOR MEANS FOR ACTUATING SAID WINDLASS MEANS IN ALTERNATE DIRECTIONS WITH RESULTANT WINDING IN AND UNWINDING OF SAID FLEXIBLE MEMBER AND CONSEQUENT APPLICATION AND RELIEF OF TRACTION ON THE PATIENT, AND CONTROL MEANS FOR SAID REVERSIBLE MOTOR MEANS INCLUDING AN ELECTRIC SWITCH AND SPRING BIAS OPERATING MEANS ENGAGING SAID SWITCH INCLUDING DEVICES ENGAGING SAID FLEXIBLE MEMBER AND TENDING TO YIELDINGLY LATERALLY DISPLACE SAID MEMBER WHEREBY IN RESPONSE TO IMPOSITION OF A TRACTION PULL ON SAID FLEXIBLE MEMBER OF A PREDETERMINED MAGNITUDE, SAID FLEXIBLE MEMBER ENGAGING DEVICES WILL BE MOVED AGAINST THE SPRING BIAS THEREON WITH RESULANT ACTUATION OF SAID SWITCH TO EFFECT REVERSAL OF SAID MOTOR MEANS AND CONQUENT UNWINDING OF SAID WINDLASS MEANS.