US1696747A - Interlocking mechanism - Google Patents

Interlocking mechanism Download PDF

Info

Publication number
US1696747A
US1696747A US73525A US7352525A US1696747A US 1696747 A US1696747 A US 1696747A US 73525 A US73525 A US 73525A US 7352525 A US7352525 A US 7352525A US 1696747 A US1696747 A US 1696747A
Authority
US
United States
Prior art keywords
shaft
controller
plug
rotation
interlocking
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US73525A
Inventor
Charles W Wyman
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sullivan Machinery Co
Original Assignee
Sullivan Machinery Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sullivan Machinery Co filed Critical Sullivan Machinery Co
Priority to US73525A priority Critical patent/US1696747A/en
Application granted granted Critical
Publication of US1696747A publication Critical patent/US1696747A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60LPROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
    • B60L15/00Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles
    • B60L15/20Methods, circuits, or devices for controlling the traction-motor speed of electrically-propelled vehicles for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/60Other road transportation technologies with climate change mitigation effect
    • Y02T10/64Electric machine technologies in electromobility
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02TCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
    • Y02T10/00Road transport of goods or passengers
    • Y02T10/60Other road transportation technologies with climate change mitigation effect
    • Y02T10/72Electric energy management in electromobility

Definitions

  • This invention relates tointerlocking mechanisms and more particularly to interlocking controlling mechanisms especially adapted to use in conjunction with the controllers and current supply connections ol' mining machines.
  • the present day coal cutting mun-ng inachinc of the electrically operated typ-e commonly provided with a suitable con'- A troller and is supplied with current through a .suitable detachable connection.
  • the controller is ordinarily ofthe rotatable typ-e and upon rotation in opposite directions from a neutral position is adapted to eii'ect the proper starting and running in opposite directions of the mining machine motor.
  • the connector plug' is ordinarily of the longitudinally insertable type and contains a number of push connections for makin-gy the 2G necessary circuits and also generally a ground connection.
  • a more specific 39 object of the invention is to provide an iin-1 proved interlocking connection. including manually kcontrollable means determining the direction of operation of the motor controller and operating to lock or release a detachable connector plug.
  • Fig. l is a plan view with parts ybroken away to different degrees-of the extreme rear end of a mining machine equipped with the illustrative embodiment of the invention.
  • Fig. 2 is a rear end elevation of the upper portion of the controller end of such a mining machine.
  • Fig. 3 is a vertical transverse section on the line 3&3 of Fig. l.
  • Fig. 4 is a vertical longitudinal section on the line of Fig. 2.
  • Fig. 5 is a vertical longitudinal section upon an enlarged scale on the line 5 5 of Fig. 2 through the controller side of the controlling mechanism.
  • Fig 6 is a vertical longitudinalsectionwith parts broken away on. the line 6*@ oft F 1gr n, showing a portion of the connector plug side of the machine.
  • Fig. 7 is a pla-n view of a portion of thc controlling mechanism.
  • l represents a mining machine frame at one side of which detach-able current supply connections generally designated 9. are arranged and at Whose other side the controller mechanism of the mining machine, generally designated 3, is disposed.
  • the connector plug is of the push type and comprises in the illustrative form three power connections-t and a ground connection 5 lhoused Within a longitudinally insertable and removable casing 6.
  • the connector plug (S is provided with a peripheral locking recess 15 Withwhich the interlocking mechanism engages and is fur ther' provided with a radially extending recess 16 in which a manually releasable spring pressed plunger 17 slidably mounted in a chamber 18 upon an element secured to the machine frame l is lengageable.
  • the function of the locking plunger 17 is to prevent blowing out of the connector plug 6 in the event of a short circuit or other condition causing an explosion within the machine casing at a time when the controller is in oil position.
  • Slidably but non-rotatably mounted upon the rectangular shaft 7 is a sleeve member 20 having peripheral teeth 20 formingv a rack.
  • the member 20 is also provided in its periphery With a longitudinally extending recess 21 Whose machine l in opposite opposite ends open into oppositely circumferentially extending peripheral recesses 22 and 23.
  • a pin 2a formed at the end of a threaded bolt 24a mounted on a part of the machine frame 1 extends'into the groove made up of the portions 21, 22 and 23 and when the sleeve 20 is in the position shown in Fig. 7 precludes rotation of the shaft 7, but upon movement of the sleeve 2O longitudinally until the pin 2/l is opposite the groove 22 or the groove 23 permits turning in one direction or the other of the shaft 7.
  • a transversely extending shaft 26 which has three flattened portions 27, 28 and 29 engageable by a leaf spring member 30 held by a bolt 31 to the machine frame.
  • a handle 32 mounted upon the end of the shaft 26 is movable into upright, horizontal, and depending positions and respectively causes engagement of the surfaces 29, 28 and 27 by the leaf spring 30 when in such positions.
  • the shaft 26 extends to a position beyond the central vertical longitudinal plane of the plug6 and passes through the groove 15.
  • the shaft 26 has a flattened portion 33 oppositegroove 15 whereby vvith the parts in the position shown in Fig.
  • the plug may be freely linserted and removed, While the axis of the shaft as shown in Fig. 6 is so close to the periphery of the plug 6 that rotation of the shaft 26 to either position correspondingV to the vertical dispositions of the handle 32 results in locking the plug against removal.
  • Rotation of the shaft 26 by movement of the handle 32 Will bring either the surface 27 or the surface 29 opposite the leaf spring 30 so that the shaft Will be held in the position to Which it is moved and either rotation of the shaft will move the cutaway portion or flattened surface 33 into a vertical position and bring a cylindrical portion of the shaft 26 into the notch 15. Accordingly, it Will be completely impossible even upon deliberate manual Withdrawal of the latch pin 17 for the plug 6 to be removed While the controller is ,in on position, this being'true irrespective of which direction the motor is running.
  • the rotation of the shaft 26 operates through the pinion 25 to move the rack sleeve 20 from the position shovvn in Fig. 7 longitudinally of the shaft 7 until the desired groove 22 or 23 comes opposite the pin 2l.
  • a shaft mounted only for rotation on aliXed axis and adapted on rotation in opposite directions from a given position to produce different circuits, and means including a member rotatable With said rotatable shaft and reciprocable longitudinally thereof'and a stationary abutment member for controlling the direction in which said co-ntroller member may be moved.
  • an electric controlling mechanism a controller operating member, a connector plug, and means controlling the operation of said-member and the removal of said plug including an independent manual operating element for said controlling means and a horizontal rotatable shaft adapted to interengage with the connector plug and provided With connect-ions With the controller operating member so as to be operative in different positions to permit operation of said controller operating member and Withdrawal of said plug.
  • a controller manual means for operating the same, a removable connector plug through which power is conducted to said mecha-V nism, and interlocking means cooperating with said plug and controller comprising a manually joperable shaft, and means controlled thereby for preventing movement of said controller except in certain positions of said'shaft, said shaft having a portion directly interlocking with said connector plug in said positions.
  • a controller In an electric controlling mechanism', a controller, manual means for operating the same, a removable connector ⁇ mechanism, and interlocking means cooperplug through Which power Yis conducted to saidY kating with said plug and controller compris ⁇ "ing a manually operable shaft, andv means controlled thereby for preventing ovement of said controller except in certain positions of said shaft, said shaft having a portion directly interlocking with said connector plug in said positions and means for yieldingly retaining said shaft in one of a plurality of positions.
  • a controller manual means for operating the same including a shaft, means for con ⁇ trolling the power circuit leading to said controller, and interlocking mechanism cooperating with said means and controller comprising a member slidably and non-rotatively connected to said shaft, stationary means engageable With said member to prevent rotation of said shaft, mannallyY operated means for effecting slidable movement to permit rotation of said shaft, and locking means for said ⁇ circuit controlling means controlled by said manually operated means.
  • a rotatableshaft adapted on rotation in opposite directions from a given position to produce different circuits
  • a handle rigidly connected to said shaft for operating the same, and means including a member slidably and non-rotatively connected to said shaft, and means engageable with said member to make control of shaft rotation dependent on the longitudinal position of said member ron said shaft.
  • a rotatable shaft adapted on rotation in opposite directions from a given position to produce different circuits
  • means comprising an element slidably and non-rotatively connected to said shaft and akv stationary lug engageable with a groove in said member to make control of shaft rot-ation depend upon the longitudinal position of said member with reference to the shaft, and manually operated means for effecting slidable movement of said member, and means con trolling the power circuit leading to said controller, said manually operated means adapted alsoto control said circuit controlling means.
  • a. controller manual means for operating the same including a shaft, a removable connector plug, interlocking mechanism cooperating with said controller and plug comprising a. member slidably and non-rotatively connected to said shaft, a handle rigidly connected to said shaft for operating the same, stationary means engageable with said member to prevent rotation of said shaft except in certain longitudinal positions of said member, manually operated means for effecting slidable movement of said member, and locling means for said plug controlled by said manually operated means.
  • a controller manual means for operating the same including a' shaft, a removable connector plug, and interlocking mechanism cooperating with said plug and controller to prevent removal of said plug While the controller is in on position, and also to prevent operation of said controller except
  • a member slidably and non-rotatively connected to said shaft, stationary means engageable With said member to prevent its rotation except in certain longitudinal positions, and means for effecting slidable movement of said member comprising a manually operated transverse shaft, a rack and pinion carried respectively by said member and shaft,

Description

Dee. 25, 1928.
C. W. WYMAN INTERLOCKING MECHANISI Filed Dec. s, 1925 Smets-sheet 1 Dec. 25, 1928. 1,696,747
c. w. wYMAN INTERLOGKING MEGHANISI Filed Dec. 5. 1925 2 Shoots-Sheet 2 Y/zarew'd layman" l lll Patented Dec. 25, 1928.
CBARLESMW. WYM'AN, OF CLARE'MONT, NEW
HAM'PSHIRE, ASSIGNOR TO SULLIVAN' MACHINERY C'QMPANY, CORPORATIQN OF MASSACHUSETTS.
INTBRLOCKING MECHANISM.
`Application med December. 5, 1925. Seri-a1 No. 73,5255.r
This invention: relates tointerlocking mechanisms and more particularly to interlocking controlling mechanisms especially adapted to use in conjunction with the controllers and current supply connections ol' mining machines. n
The present day coal cutting mun-ng inachinc of the electrically operated typ-e commonly provided with a suitable con'- A troller and is supplied with current through a .suitable detachable connection. The controller is ordinarily ofthe rotatable typ-e and upon rotation in opposite directions from a neutral position is adapted to eii'ect the proper starting and running in opposite directions of the mining machine motor. The connector plug' is ordinarily of the longitudinally insertable type and contains a number of push connections for makin-gy the 2G necessary circuits and also generally a ground connection.
It is an object' of the present invention to provide an improved interlocking con-v trolling mechanism for etecting the operation of a controller of the type specified and locking the connector plug against remo-val or insertion as this may be necessary, as for example in all cases exceptl when the controller is in oli position. A more specific 39 object of the invention is to provide an iin-1 proved interlocking connection. including manually kcontrollable means determining the direction of operation of the motor controller and operating to lock or release a detachable connector plug. Other objects and advantages of thev invention will subscquently appear In the accompanying' drawings in which one illustrative embodiment of the invention is shown:
Fig. l is a plan view with parts ybroken away to different degrees-of the extreme rear end of a mining machine equipped with the illustrative embodiment of the invention.
Fig. 2 is a rear end elevation of the upper portion of the controller end of such a mining machine. n
Fig. 3 is a vertical transverse section on the line 3&3 of Fig. l.
Fig. 4 is a vertical longitudinal section on the line of Fig. 2.
Fig. 5 is a vertical longitudinal section upon an enlarged scale on the line 5 5 of Fig. 2 through the controller side of the controlling mechanism.
Fig 6 is a vertical longitudinalsectionwith parts broken away on. the line 6*@ oft F 1gr n, showing a portion of the connector plug side of the machine.
Fig. 7 is a pla-n view of a portion of thc controlling mechanism. I In the accompanying drawings in which it has been deemed unnecessary to illustrate the specitic details ot the controller mechanism and of the connector plug since these may obviously assume different forms, l represents a mining machine frame at one side of which detach-able current supply connections generally designated 9. are arranged and at Whose other side the controller mechanism of the mining machine, generally designated 3, is disposed. The connector plug is of the push type and comprises in the illustrative form three power connections-t and a ground connection 5 lhoused Within a longitudinally insertable and removable casing 6. Thel details of the circuit controlling mechanism, as mentioned above, are not disclosed, but operation of the motor of the mining directions is obtainable by opposite rotation of a squared operatino` shaft 7 which carries a cam plate 8 With Willich a pivoted locking element 9 cooperates under the tension of a spring l0. Shaft is rotatable by a handle l2 which in its neutral position is disposed as shown in fullv lines in Fig. 2, but which may be moved in opposite directions through angles of slightly less than 180 degrees to the dotted positions shown in that figure.
The connector plug (S is provided with a peripheral locking recess 15 Withwhich the interlocking mechanism engages and is fur ther' provided with a radially extending recess 16 in which a manually releasable spring pressed plunger 17 slidably mounted in a chamber 18 upon an element secured to the machine frame l is lengageable. The function of the locking plunger 17 is to prevent blowing out of the connector plug 6 in the event of a short circuit or other condition causing an explosion within the machine casing at a time when the controller is in oil position. Slidably but non-rotatably mounted upon the rectangular shaft 7 is a sleeve member 20 having peripheral teeth 20 formingv a rack. The member 20 is also provided in its periphery With a longitudinally extending recess 21 Whose machine l in opposite opposite ends open into oppositely circumferentially extending peripheral recesses 22 and 23. A pin 2a formed at the end of a threaded bolt 24a mounted on a part of the machine frame 1 extends'into the groove made up of the portions 21, 22 and 23 and when the sleeve 20 is in the position shown in Fig. 7 precludes rotation of the shaft 7, but upon movement of the sleeve 2O longitudinally until the pin 2/l is opposite the groove 22 or the groove 23 permits turning in one direction or the other of the shaft 7. Opposite longitudinal movement of the sleeveA 2O is effected by a pinion 25 formed upon .a transversely extending shaft 26 which has three flattened portions 27, 28 and 29 engageable by a leaf spring member 30 held by a bolt 31 to the machine frame. A handle 32 mounted upon the end of the shaft 26 is movable into upright, horizontal, and depending positions and respectively causes engagement of the surfaces 29, 28 and 27 by the leaf spring 30 when in such positions. lThe shaft 26 extends to a position beyond the central vertical longitudinal plane of the plug6 and passes through the groove 15. The shaft 26 has a flattened portion 33 oppositegroove 15 whereby vvith the parts in the position shown in Fig. 6 the plug may be freely linserted and removed, While the axis of the shaft as shown in Fig. 6 is so close to the periphery of the plug 6 that rotation of the shaft 26 to either position correspondingV to the vertical dispositions of the handle 32 results in locking the plug against removal. l
From the description Which has been given the mode of operationl of this device 'will be clearly apparent. Let it be assumed that the plug 6 is in position establishing electrical connections` from the line to the machine and that the latch 17 is seated in the socket 16. The recess 15-then overlies the shaft 26 and the machine runner desiring to start the mining machine in one direction or the other will move the handle 32 from the position shown in Fig. 1 either clockwise or countercloclnvise depending upon the direction of rotation of the motor desired. Rotation of the shaft 26 by movement of the handle 32 Will bring either the surface 27 or the surface 29 opposite the leaf spring 30 so that the shaft Will be held in the position to Which it is moved and either rotation of the shaft will move the cutaway portion or flattened surface 33 into a vertical position and bring a cylindrical portion of the shaft 26 into the notch 15. Accordingly, it Will be completely impossible even upon deliberate manual Withdrawal of the latch pin 17 for the plug 6 to be removed While the controller is ,in on position, this being'true irrespective of which direction the motor is running. The rotation of the shaft 26 operates through the pinion 25 to move the rack sleeve 20 from the position shovvn in Fig. 7 longitudinally of the shaft 7 until the desired groove 22 or 23 comes opposite the pin 2l. lt will then be possible for the operator to move the handle 12 in the desired direction to effect controller operation. `Obviously, if theliandle 32 is moved to permit rotation of the handle 12 When the plug 6 is not in position, the plug cannot be inserted. Moreover, rotation ofthe handle 32 and shaft 26 is impossible With the plug partially inserted. lt Will therefore be apparent that the machine is Well protected against willful or accidental manipulation of the parts in a manner to produce likelihood of explosions.
While l have in this application specifically described one embodiment which my invention may assumefin practice, it Will be understood that this invention may be modilieu andV embodied in various other forms Without departing from its spirit or the scope of the appended claims. v
`What l claim as neuv and desire to secure by Letters Patent is: i 1. In an electric controlling mechanism, a shaft mounted only for rotation on aliXed axis and adapted on rotation in opposite directions from a given position to produce different circuits, and means including a member rotatable With said rotatable shaft and reciprocable longitudinally thereof'and a stationary abutment member for controlling the direction in which said co-ntroller member may be moved.
2. ln an electric controlling mechanism, a controller operating member, a connector plug, and means controlling the operation of said-member and the removal of said plug including an independent manual operating element for said controlling means and a horizontal rotatable shaft adapted to interengage with the connector plug and provided With connect-ions With the controller operating member so as to be operative in different positions to permit operation of said controller operating member and Withdrawal of said plug.
3. In an electric controlling mechanism, a controller, manual means for operating the same, a removable connector plug through which power is conducted to said mecha-V nism, and interlocking means cooperating with said plug and controller comprising a manually joperable shaft, and means controlled thereby for preventing movement of said controller except in certain positions of said'shaft, said shaft having a portion directly interlocking with said connector plug in said positions. Y
l. In an electric controlling mechanism', a controller, manual means for operating the same, a removable connector` mechanism, and interlocking means cooperplug through Which power Yis conducted to saidY kating with said plug and controller compris` "ing a manually operable shaft, andv means controlled thereby for preventing ovement of said controller except in certain positions of said shaft, said shaft having a portion directly interlocking with said connector plug in said positions and means for yieldingly retaining said shaft in one of a plurality of positions.
.5. In an electric controlling mechanism, a controller, manual means for operating the same including a shaft, means for con` trolling the power circuit leading to said controller, and interlocking mechanism cooperating with said means and controller comprising a member slidably and non-rotatively connected to said shaft, stationary means engageable With said member to prevent rotation of said shaft, mannallyY operated means for effecting slidable movement to permit rotation of said shaft, and locking means for said` circuit controlling means controlled by said manually operated means.
6. In an electric controlling mechanism, a rotatableshaft adapted on rotation in opposite directions from a given position to produce different circuits, a handle rigidly connected to said shaft for operating the same, and means including a member slidably and non-rotatively connected to said shaft, and means engageable with said member to make control of shaft rotation dependent on the longitudinal position of said member ron said shaft.
7. In an electric controlling mechanism, a rotatable shaft adapted on rotation in opposite directions from a given position to produce different circuits, means comprising an element slidably and non-rotatively connected to said shaft and akv stationary lug engageable with a groove in said member to make control of shaft rot-ation depend upon the longitudinal position of said member with reference to the shaft, and manually operated means for effecting slidable movement of said member, and means con trolling the power circuit leading to said controller, said manually operated means adapted alsoto control said circuit controlling means.
- 8. In an electric controlling mechanism, a. controller, manual means for operating the same including a shaft, a removable connector plug, interlocking mechanism cooperating with said controller and plug comprising a. member slidably and non-rotatively connected to said shaft, a handle rigidly connected to said shaft for operating the same, stationary means engageable with said member to prevent rotation of said shaft except in certain longitudinal positions of said member, manually operated means for effecting slidable movement of said member, and locling means for said plug controlled by said manually operated means.
9. In an electric controlling mechanism, a controller, manual means for operating the same including a' shaft, a removable connector plug, and interlocking mechanism cooperating with said plug and controller to prevent removal of said plug While the controller is in on position, and also to prevent operation of said controller except When the locking means for the plug is effective, a member slidably and non-rotatively connected to said shaft, stationary means engageable With said member to prevent its rotation except in certain longitudinal positions, and means for effecting slidable movement of said member comprising a manually operated transverse shaft, a rack and pinion carried respectively by said member and shaft,
and a locking device for said plug controlled by said transverse shaft.
In testimony whereof I affix my signature.
CHARLES W. WYMAN.
US73525A 1925-12-05 1925-12-05 Interlocking mechanism Expired - Lifetime US1696747A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US73525A US1696747A (en) 1925-12-05 1925-12-05 Interlocking mechanism

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US73525A US1696747A (en) 1925-12-05 1925-12-05 Interlocking mechanism

Publications (1)

Publication Number Publication Date
US1696747A true US1696747A (en) 1928-12-25

Family

ID=22114202

Family Applications (1)

Application Number Title Priority Date Filing Date
US73525A Expired - Lifetime US1696747A (en) 1925-12-05 1925-12-05 Interlocking mechanism

Country Status (1)

Country Link
US (1) US1696747A (en)

Similar Documents

Publication Publication Date Title
US1696747A (en) Interlocking mechanism
US1556829A (en) Interlocking mechanism
US2126843A (en) Operating mechanism for lifting jacks
DE616721C (en) Safety device for electric motor driven spin dryer for laundry u. like
US1940930A (en) Electrical apparatus
US2366441A (en) Controller mechanism
US1940928A (en) Electrical apparatus
US2148473A (en) Electrical controlling apparatus
US1696748A (en) Controlling apparatus
US1363373A (en) Automobile-lock
DE378663C (en) Influenced by a centrifugal pendulum electrical control device for power machines u. like
US1556823A (en) Electric switch
US1569713A (en) Controller
US1320800A (en) Augustus c
US2719927A (en) Electrical control systems and control devices therefor
US1730396A (en) Automobile lock
US1718513A (en) Controlling mechanism
DE904987C (en) Switching lock for large meat processing machines
US2270439A (en) Combination lock with electrical switch control
AT153624B (en) Electric switchgear for motor vehicles.
GB182458A (en) Improvements in or relating to electrically propelled mining machines
GB242220A (en) Improvements in electric controlling apparatus
US1455138A (en) Automobile lock
US1376454A (en) Control apparatus
US1639354A (en) Engine ignition lock