US2212930A - cochrane - Google Patents

Description

ug- 27, 1940- R. A. cocHRANE TIMER Filed June l1, 1937 65450 INVENTOR I xlll.

Ro beviF A. Cochrane BY /rn/ ATTO R N EYY Patented Aug. 27, 1940 UNTE STATES liiiTEN'l FFiCE TIMER Robert A. Cochrane, Los

f, Calif.

Application June 11, i935?, Serial No. 1131!,734

4 Claims.

y A equipment including an internal combustion engine is used under a system in which. pay iol' the use of the equipment is based upon the cried o operation. Trucks for example may "oe thu rented; and since there may be ended period y. of inactivity, an equitable system of charging for the use of such equipment is on the basis ci the total times oi activity.

It is one oi the objects of this invention to provide a simple and reliable time recording apparatus especially adapted for this character of work.

it is another object of this invention to provide a recording time measuring apparatus that will function successfully under such extreme conditions of shock., vibration and dust as would reasonably be expected to cause interruption or damage to a clock works mechanism of conventional design.

As the readings oi this device will often be used as the basis for the computation of earned rentals, and as the operator o1" the equipment to which it is attached, may be the renter of said equipment, it is also an object of this invention to provide a time recording apparatus for this class of service that is tamper prooi and will require no winding, changing of charts nor electrical energy.

A further object of my invention is the provision ci a time recording apparatus embodying any form oi timer mechanism having a known and constant interval of operation, such as a dash pot, and which is set into operation by' a partial vacuum supplied thereto from the suction side of an engine periodically through operation of a valve mechanism so as to cause uniform This form will now be ldescribed in deillustrating the general principles of the incation. taii,

vc? Y'on; but it is to he understood that this detailed description is not to be taken in a limitim s.

. corporating the invention, shown as a housing, and as associated with an 1() is a longitudinal sectional View of the shown in Fig. l;

appar t is an enlarged sectional view taken along -lane lI--fl of Fig. 3;

5 is a fragmentary view similar to Fig. 4, vith some of the parts in section;

Fig. G is a sectional view taken along plane 6 5 oi Fig. fr;

Fig. is a sectional View taken along plane 'F-l of T g. 4; and

engine i, or other mechanism that develops a 30 pressure ventiel. This internal combustion engine i be stalled on a truck or utilized for other purposes. It is shown as provided with an intake manifold 2, forming a part of the intake passages to the cylinders of the engine l.

The timer mechanism, shown in greater detail in Figs. 2 to 8 inclusive, is shown in Fig. l as in a locked or sealed box or housing 3, which may be appropriately supported at or near the engine l. Although this housing 3 may be locked 40 or sealed to ensure against unauthorized tampering, it is provided with a viewing window 4 through which a register, indicator, or recorder enclosed within the housing 3 may be viewed. In the present instance a register mechanism 5 45 is utilized, and is shown in Figs. 2 and 3 as a counter mechanism having an actuating oscillatable arm G. its dial is placed below the window d, which may be formed of a glass plate held by a frame 'l to the lower side of the top of housing 3. 50

The timer mechanism must have a known and substantially constant operating interval, that is, that interval between the setting of the mechanism into operation and the cessation in operation. Such a timer mechanism suitable for the a transverse sectional view taken along 15 25 stem i9.

purpose is a dash pot in which the operating interval of the piston in its retarded stroke within the cylinder is known and constant.

Hence, as a timer mechanism I employ a dash 5 pot l, shown in Fig. 2, as comprising a piston structure 8 operating within a cylinder structure 9. Upon the bottom i8 of the housing 3 the two cylinder heads Il and l2 may be supported, as by the feet Il. Between these two 10 cylinder heads there is clamped the cylinder proper i3.v The constructionis made air tight at the right hand end of the cylinder by the aid of an annular gasket lli. The assembly of the heads il and I2 with the cylinder proper I3 is effected by the aid of a plurality of through boltsY I5 passing through ears I6 formed on the cylin-v der heads l l and I2.

The cylinder head l I is provided with a centralV guide boss I8, through which the piston stem, I8 extends.

30. operated by the aid of a projection 25, shown as formed integrally with an arm 26 fastened to thel left hand end of the stem I9. As the piston structure4 8 moves inwardly with respect to the cylinder i3, the projection strikes the arm e and causes the register 5 to record the number of inward reciprocations. The register 5 and the operating Aarm 6 are so arranged that movement of the piston structure g 8 outwardly, that is, toward the left,will cause the arm 6 to rotate in a clockwisedirection without operating the registerV 5. In this way each complete cycle of piston operations causes one operative oscillation only of the arm 6.

YThe numbers on the counter 5 may be arranged so as to indicate directly the hours and tenths of hours comprised by integration of the intervals of operation of the mechanism l. Ihus a complete reciprocation may be so timed as tov occur in siX minutes, that is, once in one-tenth of A an hour. Accordingly the right hand gure appearing on indicator 5 will represent tenths of hours; and the remaining V:ligures will represent the wholenumber of hours.

MIn the present instance the register 5 is show as conveniently supported upon ak bracket 27 fastened to the cylinder head ll.

Connections areY provided from the interior chamber of cylinder structure 9 to the intake manifold 2.

This connection may be sealed against removal as bypappropriate seal 30. The other end of connection 28 extends toa nipple structure 3l supported onthe side wall 32 of the housing 3.

6,This nipple structure is engaged by a nut 33 car- Y `ried by the end of the conduitV 28 and sealed against removal, as by a wire 34 and seal 35.

YThe inside end of the nipple structure 3i may be similarly connected to a connection 38 which 7Qleadsto'a valve `structure, to be described in detail hereinafter. From the valve structure the connection proceeds, as by aid of lconnection M, tothe nipplel Aattachedpto the cylinder head l2,'

and i inV communication with the f, cylinder 75.5chamber..

Thus there is a conduit 2a whichV is connected at one end 29 into the manifold 2.

When the valve mechanism between connections 36 and 41 is open, the partial vacuum existing in manifold 2 is effective within the cyl-l inder space, and causes the piston structure 8. to move inwardly, that is, toward the right as viewed in Fig. 2. However, upon approaching the extremity of its stroke, the piston structure 8 and Valve stem i9 are so arranged that they actuate the valve means to disconnect the source of Vacuum 2, and the piston 8 is moved outwardly or toward the left. This is accomplished by the aid of a compression spring 38 located within the cylinder space and which had been compressed by the inward movement of the piston structure 8. The motion of the piston structure 8 inwardly is quite rapid and the spring 38 is so designed that the pressure effects created by the l partial vacuum within the cylinder space is sufcient under any condition of engine operation to overcome the spring 38. However, when the partial vacuum is destroyed, the piston structure 8 is caused to move slowly towardv the left or outwardly. This is accomplished by providing a restricted vent from the cylinder space so that it is only at a slow rate that the vacuum is destroyed in the cylinder space.

This restrictedvent is provided by the aid of a needle valve structure 39 fastened in the head l2. The atmospheric vent or connection is indicated at 8. The size of the vent is controllable by a needle valve closure operated by the thumb screw il engaging threads within the body'of the structure 39. Itinay be held in adjusted position as by the aid of the check nut 42. Thus by accurate adjustment of the thumb screw 42, the period required for the piston structure B to move to its extreme outward position may be controlled. Of course, the vent 4U is so greatly restricted that it does not interfere appreciably with the creation of the partial vacuum within the cylinder space, when the valve mechanism connects the cylinder space with the source of Vacuum 2. In order to relieve any pressure differential on the left of piston 8, the head Il may be appropriately vented.

Upon arrival of the piston structure 8 near its extreme outward position, the valve mechanism is actuated to reconnect the cylinder space to the manifold 2, and the cycle of operations is repeated. In order that the interior of housing 3 may at all times be at atmospheric pressures, a dust-proof opening Ais provided in the wall 32. This opening is formed by a small cup-like structure 43 having apertures therein and filled withY dust'trapping material, such asvoil soaked snarled l wire. It may be covered over by an apertured plate M. Thus arbreather is Yprovided for the interior of the housing or casing 3 which is pref;

erably otherwise air-tight.

The control valve mechanism is illustrated most clearly in Figs. 4 toY 8 inclusive. Thus in Figs. l and 6, the connection 36 is shown as leading to aperture 136 within ablock 45. The connection 4l from the cylinder nipple 31 is similarly l connected to another aperturell within the block 45. Y Y Y y y The connection between apertures 48 and 48 is controlled by a slide valve plate 49.

This valve plate 69 has Va depending boss 50, provided with lviewed in Fig. 4, will bring the recess 5I out of communication with the aperture 46. The plate 49 is guided as by the aid of a pair of screws 52 and 53 passing'through slots, such as 54 and 55 in the plate 49. The screws 52 and 53 are fastened into the bar 45. Compression springs 56 may be interposed between the heads of screws 52, 53 and the top of plate 49, so as to ensure substantially air-tight t between the boss 58 and the top of bar 45.

The plate 49 is adapted to be quickly snapped to open and to closed position by an over-center mechanism to be later described. It is shown as joined as by the aid of its upstanding ear 51 (Figs. 4 and 6) to a corresponding ear 58 on the top plate 59 of a movable carriage structure to be hereinafter described.

This movable carriage structure as shown most clearly in Figs. 7 and 8, includes, in addition to its top plate 59, a lower plate 68. The two plates are held in spaced relation at one end by the aid of a pair of spacer bushings 6I (Figs. 5 and '7) through which pass the fastening screws 62. At the opposite end the plates 59 and 68 of the carriage structure are held in spaced relation by carriage guide rollers 63, the pivot pin 64 of which may be fastened as by riveting to the plates 59 and 68.

This carriage structure is guided for movement to control the valve mechanism by the aid of a stationary guide structure. This guide structure is shown most clearly in Figs. 4, 5, '7 and 8. It comprises a bottomplate 65 supported in spaced relation to the bottom wall I8 of the casing. It also has a top plate 66 which may be connected to the bottom plate 65 by the vertical wall 61 (Fig. 5). These top and bottom plates 65 and 66 are embraced between the top and bottom plates 59 and 68 of the carriage structure. The carriage structure is intended to slide over these spaced plates 65 and 66.

Limits are imposed to the extent of slide of the carriage to correspond with the opening and closing of the valve mechanism, These limits may be provided by the transverse bar stops 68 joined to the plates 65 and 66. In Fig. 8, the carriage structure 59-68 is shown as in its extreme right hand position against the right hand stops 68; this corresponds to the uppermost position of Fig. 4, the valve mechanism being open. Upon movement of the carriage longitudinally to cause it to contact with the left hand stops 68 (Fig. 8) the valve mechanism is closed.

The snap-over action between these two extreme positions is provided by the aid of a longitudinally movable bar 69 slidably guided between the upper and lower stationary plates 66 and 65. 'This bar 69 as shown most clearly in Fig. 8, may be provided with slots 18 and 1I through which pass the guide screws 12, to constrain the movement of the bar 69 in a direction parallel to the movement of the valve plate 49. The carriage rollers 63 engage one edge of the bar 69. The bar 69 is also provided with a pair of tapered notches 13 and 14 at one edge thereof. Between these notches is formed a tooth 15. A roller 16 supported by the carriage 59-60 is adapted to engage within either one or the other of the notches 14 and 15. This roller is also carried by the carriage structure 59-6I. Roller 16 is provided with a pivot pin 11 extending through slots 18 and 19 in the upper and lower plates of the carriage. Furthermore, the roller 16 is urged resiliently into the corresponding notch by the aid of the tension springs 88 and 8|. These rollers 63 and 16 thus form a convenient guide for properly defining the movement of the carriage with respect to bar 69. One end of each of these springs is anchored to the corresponding end of the pivot pin 11. The other end of each of the springs is anchored to a screw 82 or 83 supported on the flanges 84 or 85, respectively formed on the top plate 59 and bottom plate 60 of the carriage structure.

It is apparent that when the bar 69 is moved upwardly as viewed in Figs. 4 and 5, the springs 88 and 8l will rst be stretched until the roller 16 has moved completely out of the notch 13, up to the apex of tooth 15; and thereafter the roller will be urged by the springs and BI quickly into the lower notch 14. Due to the slope of the walls of the notch 14, the carriage as a whole will be moved downwardly as viewed in Figs. 4 and 5, or toward the left as viewed in Fig. 8. This causes a corresponding movement of Valve plate 49, causing the val-Ve mechanism to close.

Conversely, when the valve mechanism is closed, a movement of the bar 69 downwardly will cause eventually a corresponding quick motion of carriage 59-68 upwardly to open the valve. The vertical wall 61 is appropriately slotted as indicated at 86 (Fig. 5) to permit the roller 16 to contact with the bar 69.

The reciprocations of the bar 69 are controlled by motion of the piston stem I9 and the arm 29 attached thereto. Thus the bar 69 is provided with an upturned flange 81 (Figs. 4 and 8). To this flange is attached a threaded rod 88. This threaded rod 88 carries the adjustable abutments, such as the nuts 89 and 98. The arm 26 is apertured so that rod 88 may pass therethrough. Between these nuts 89 and 90 the arm 26 is arranged to travel. When the arm 26 is carried suiciently toward the left as viewed in Fig. 2, it contacts with the abutment 90 to draw the bar 69 downwardly as viewed in Fig. 4, and to place the bar in valve opening position, as illustrated in Fig. 6. However, as soon as this is accomplished, the partial vacuum is immediately effective and the piston structure 8 moves rapidly toward the right as viewed in Fig. 2. Near the extremity of its motion, the arm 26 contacts with the other abutment 89, and urges the bar 69 upwardly as viewed in Fig. 4. This upward motion as heretofore explained, causes the carriage structure and the valve plate 49 rapidly to snap downwardly to valve closing position. Thereafter the cycle is repeated, during the entire interval of engine operation.

The operating interval of the dash pot, that is, the time during which the piston structure 8 and its associated stem I9 moves outwardly of the piston is accurately controllable by the aid of the adjustable vent 40, and thus the operating interval of the dash pot can be timed and made constant. The timing function can thus be accurately calibrated.

The mode of operation of the system is quite apparent from the foregoing. With the bar 69 in valve opening position, the recess 5I in plate 49 effects the vacuum connection from the manifold 2 to the cylinder space. Immediately the piston structure 8 and valve stem I9 move rapidly toward the right as viewed in Fig. 2, compressing the spring 38. Near the extremity of this motion, the arm 26 contacts the abutment 89. Thereafter the bar 69 is moved upwardly as viewed in Figs. 4 and 5 or to the right as viewed in Fig, 8. The roller 16 of the carriage 59-68 75 isurged outwardly of the notch i3 by this upward movement. Asrsoon as this roller passes the apex of the tooth l5, the carriage structure is rapidly moved in a downward direction. This carriage structure carried with it the plate 49, and the valve mechanism is closed. Thereafter the partial vacuumv is no longer eiective to hold the piston structure t in its inward position, the vacuum being gradually destroyed by the vent di). The spring Se urges the piston structure 8 outwardly at a'slow rate. At the extremity of this outward movement, the arm 26 contacts the abutment Si) and thereafter pulls the bar G9 downwardly to the position illustrated in the drawing.k This downward movement of'bar E9 eventually causes theeroller 'i3 to snap upwardly into the position illustrated in Fig. 5, and the valve plate @d moves to the opened position shown in Fig. 6. The cycle is then repeated as often as permitted during operation of engine l.

From the preceding operation of the time recording mechanism, it will be clear that with each cycle of operation, the piston of the dash pot is reset or moved to the right hand end of theV cylinder under each power impulse produced by the partial vacuum admitted to the cylinder, and that althoughA there is a slight variation in the power of the impulses due to the variation in the degree of vacuum produced in the intake manifold, such variation in power of the impulses is negligible for all practical purposes, as it does not affect the accuracy of the mechanism required to time and record the integrated periods of operation of the engine. This is due to the fact that the dash pot is so designed that even the lowest degree of vacuum produced in the intake manifold is sucient to rapidly move the piston to set position; and what slight variation may occur in this movement is negligible as compared to the slow movement of the piston to unset position. Tests conducted with an apparatus constructed in accordance with my invention and under extreme conditions of suction iuctuation showed that where the dash pot required siX minutes to complete one cycle of operation, 357 seconds were consumed by the piston in its movement to unset position, while only three seconds were consumed by the piston in its movement back to set position. In other words, the time consumed in the movement of the piston to set and unset positions was in the ratioof 119 to 1,

What is claimed is:

1. In a time registering apparatus; a dash pot including a vented cylinder, aV piston, and a spring for slowly moving the piston in one direction in the cylinder to an unset position; means adapted for connection to the suctionside of an engine and communicating with said cylinder to cause the resultant Vacuum to rapidly move said piston to a set position against the tension of said spring; and a valve mechanism operable by movement of said piston for disconnecting the cylinder from the enginev upon the piston reaching set position.

2. In an apparatus for registering the periods of operation of an engine; a dash pot having a cylinder with a restricted Vair vent, and a piston; means adapted to control the connection of the cylinder to the suction side of an engine to cause ther piston to move rapidly in one direction in the cylinder; means for yieldably urging the piston in the opposite direction in the cylinder to cause relatively slow movement thereof under the action of said vent; and means for actuating the controlling means to establish the connection between the engine and the cylinder when the piston is moved to a predetermined position by said urging means, and to cause a disconnection between the cylinder and engine when the piston is moved by the engine suction to another posi-l tion.

3. In an apparatus for measuring the periods of time of operation of anyengine providing a source of pressure differential; means for converting the pressure differential into periodical power impulses; and a dash pot correlated to said means so as to be periodically reset by the power impulses.

4. In an apparatus for measuring the periods of time of operation of any engine providing a source of pressure differential; a mechanism having an element rapidly movable in one direction 4to a set position and slowly movable n the opposite direction to an unset position; and valved means adapted for periodically connect-V ing said mechanism to a source of pressure -diierential so as to cause rapid movement of the element to set position after each slow movement of the element to unset position.

ROBERT A. COCI-IRANE.

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