US1668520A - Transmission lock - Google Patents

Description

Patented May 1, 1928.

warren STATES PATENT OFFICE;

PERRY L. TENNEY, F MUNCIE, INDIANA, ASSIGNOR T0 GENERAL MOTORS COR- PORATION, 0F DETROIT, MICHIGAN, A CORPORATION OF DELAWARE.

TRANSMISSION LOCK.

Application filed August 15, 1924!. Serial No. 732,239.

This invention relates to vehicle locks, and is illustrated as embodied in a key-controlled lock for an automobile transmission.

One object oftheinvention isto provide l a simple lock having an angularly-movable bolt for a transmission oi' the type having shifter forks with sliding plate-like supporting portions, one or the other of which is locked inidle position byk an interlocking plate shifted transversely `by the gear-shift lever. In one desirable arrangement the bolt locks one shifter fork directly, as by having a portion arranged to be turned into ra notch in the edge of the fork, and locks l5 the other fork indirectly through the interlocking plate. y 'I`heinterlocking plate is shown with a notch in its edge which ex `tends inwardly and then parallel to theV edge, to define a finger behind which a sec ond locking portion of the bolt 1s turned to lock the plate against transverse movement while it isinterlocked with the other shifter fork.

Another object of t-he invention is to force 2:5l the driver to use his transmission lock, byV

having an electric switch, preferably the ignitionswitch, mounted on the transmission and operated by the transmission lock, so that the transmission must bev locked to shut off theengine. A simple and reliable arrangement of this character is provided, the novelieatures being pointed out in the appended claims.

The above and other objects` and features following description of one illustrative embodiment shown in the accompanying drawings, in which:

Figure 1 is a horizontal section through the top of a transmission, showing the means for opening and closing the switch from the lock;

Figure 2 is a vertical section on the line -2f2 of Figure 1; t

Figure 3 is a side elevation of the bottom of the key-controlled locking bolt; Y

Figure i is a top plan view of part of the interlocking plate, showing the notch for the locking bolt; Y f

Figure 5 is a top plan view yof part of one of the invention will be apparent from the v or the shifter forks, showing the notch for the locking bolt; i y

Figure (3 is a section corresponding to part of vFigure 1, but showinga different means for operating the switch plunger;

Figure T is a View showing the locking mechanism in plan.

The illustrated transmission is inclosed in a housing 10 withka detachable cap 12 held by screws or bolts 14 which also serve to hold a Vstamping or supporting plate 16 clanipedat its edges between the housing and cap. The transmission is of the type in which the sliding gears are selectively shifted by one of two shifter forks 18 and 20, slidably supported between stamping 16 and an upper stamping secured thereto by bent integral lingers'e. Each shifter fork has a notch '76 in its outer edge, into one or the other of which projects the correspondingone of two downwardly-bent iingers 80, 82 cuan interlocking plate 26 having a longitudinal slot 28 embracing a plunger 30 yieldingly urged bya spring 32 downwardly from af gear shift lever 84, and the lower end or' which enters one o a pluthereby yieldably hold the lever in the vas rious positions in which it may be placed. Thus the interlocking plate is moved vtransversely by the gear shift lever to lock the idle shifter fork and to move the lower end of the plunger 30 into one or the other oi' the notches 84, 84H, one in each shifter fork; the slot 28 permitting movement of the lever to operate the shifter fork which is not locked. A transmission of this type is described .in detail in my application No.. 637,-k

rality of depressions Soin the plate 16 to partly dened by a finger 50, so that the notch extends into the plate and then to the right (Figure 4) parallel to the edge, to deline a shoulder 52 on finger 50, so arranged that when bolt La is turned to locking posi tion a half-round section 54 will be turned to hook behind the shoulder to prevent transverse movement of the interlocking plate, thus locking shifter fork 2O indirectly through the interlocking plate.

Bolt t carries a projecting pin 56, op-

erable when the transmission is locked to' o. U v\. ly closing the ignition circuit. ringers or brushes 6a are carried by an insulating panel 72 forming one end of a housing 74 threaded into an opening in the transmission housing. ltwill be seen that the switch, including panel 72, housing 7a, brushes 6a, plunger 5S, and spring 60, forms a self-contained unit which requires for assembly merely to be threaded into the opening in' the transmission housing', when the transmission is unlocked, there being no joints or connections of any kind to be made.

ln Figure 6 is shown an arrangement for moving the switch plunger 58 positively in both directions. Spring GO is omitted in this arrangement, and bolt 44 carried a two arm member 15G of resilient sheet metal, the lower arm of which is forked to engage under the head ofthe plunger to move it in one direction and the upper arm of which engages the top of the head to move it in the other direction. This obviates reliance on a spring for moving the plunger in one direction.

While one illustrative embodiment of the invention has been described in detail, it is not the intention to limit its scope to that particular embodiment, or otherwise than by the terms of the appended claims.

I claim:

Y l. A combined transmission lock and electric switch mechanism comprising, in coinbinatioii, a pair of gear-shifting members, an interlocking plate cooperating with said members to prevent their movement, a keycontrolled locking bolt movable to lock one gear-shifting member directly and the other through the interlocking plate, an electric switch, and means operated by movement of the bolt to open the switch when the gearrecesso shifting members are locked and to close the switch when they are unlocked.

2. fr transmission having, in combination, a supporting plate, two reciprocating gear shifting members supported by said plate, and having each a notch so arranged that said notches may register with one another; an oscillating gear shifting lever having a spring pressed plunger at its lower end adapted to enter one or the other of said notches as said lever is moved sidewise pre paratory to shifting one of the gear shifting members aforesaid; and depressions rovided in said supporting plate and into which the lower end of said plunger enters, to thereby yieldably hold the vsame within the notch in the gear shifting member into which it is moved.

3. A transmission having, in combination,

unit merely by threading it into and out ofV the opening and being operative when in' place without other connection.

4;. A' transmission having, in combination, two shifter forks including plate-like supporting sliding portions, an interlocking plate resting upon and shiftable transversely of the shifter forks to lock one or the other of them in idle position, the shifter forks being held against transverse movement and he interlocking plate being held `against longitudinal movement, a gear-shift lever engaging the interlocking plate and adapted to move it'transversely yand Which'lever adapted to engage the unlockedrshifter fork and to move it longitudinally, and a key-controlled locking bolt constructed and arranged 'for angular' movement to lock one of the shifter forks directly against longitudinal movement and simultaneously to lock the' interlocking plate a ainst transverse movement while the inter ocking plate isl in a position locking the other shifter fork against longitudinal movement.

A transmission having, in combination, two shifter forks including plate-like supporting sliding portions, an interlocking plate resting upon and shiftable transversely of the shifter forks to lock one or the other of them in idle position, the shifterforks being held against transverse movement and the interlocking plate being held against longitudinal movement, one shifter fork having a notch in its side edge and the interlocking plate havingin its adjacent side edge a notch cut inwardly andy then in a direet-ion parallel to said edge to form a hookshaped finger, a gear-shift lever for moving the interlocking plate transversely and for shifting the unlocked shifter fork longitudinally, and a key-controlled locking bolt arranged for angular movement and having a locking part turned into the shifter fork notchby such movement to lock the corresponding fork directly against longitudinal movement andhaving another locking partV turned by such angular movement behind the finger to lock the interlocking plate against transverse movement and thereby ini PERRY L. TENNEY.

Images