US3678622A

US3678622A - Safety reverse for automatic parking gates

Info

Publication number: US3678622A
Application number: US62816A
Authority: US
Inventors: Harold L Miller
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-08-11
Filing date: 1970-08-11
Publication date: 1972-07-25
Anticipated expiration: 1989-07-25

Abstract

An improved automatic drive mechanism for automobile parking lot gates incorporating a reversing mechanism to immediately raise the gate if the gate strikes an object as it is lowering. An electrical interlock prevents the gate from raising when it has reached its final horizontal position.

Description

D United States Patent [151 3,678,622 Miller 1 [451 July 25, 1972 [541 SAFETY REVERSE FOR AUTOMATIC 1,934,429 11/1933 Jenkins .L ..49/2s PARKING GATES 2,247,129 6/1941 Little ..49/2s 2,883,182 4 1959 B0 em .....49 28 X [72] Inventor: Hl IOld L. mu", 946 Lakepointe, GIOSSG 3 45 7; 9 2 u 49: x 48230 3,078,407 2/1963 Schaefer.. .....49/28 x [22] Filed: Aug. 11, 1970 3,129,936 4/1964 Carlson ..49/28 X 3,174,743 3 1965 B ..49 28 21 Appl. No.: 62,816 I I Primary Examiner-Dennis L. Taylor 52 us. 01 ..49 2a oy Forster & Farley [51] Int. Cl. ..E05! 15/04 [58] Field of Search ..49/28, 29, 26, 27 ABSTRACT An improved automatic drive mechanism for automobile [56} Rdmnces Cited parking lot gates incorporating a reversing mechanism to im- UNITED STATES PATENTS mediately raise the gate if the gate strikes an object as it is lowering. An electrical interlock prevents the gate from rais- 1,367,684 2/1921 Briggs ..49/28 ing when it has reached its fi l horizontal position 3,204,170 8/1965 Monks .49/28 X 1,893,824 1/1933 McWhirter ..49/28 7 Claims, 4 Drawing Figures Patented July 25, 1972 3,673,622

2 Sheets-Sheet 2 l r 34* l g); (9,

l NVENTOR HAAOIO Z. M/Zlffi ATTORNEYS SAFETY REVERSE FOR AUTOMATIC PARKING GATES BACKGROUND OF THE INVENTION Automobile parking lot gates having wooden arms that rotate down into a horizontal position blocking the entrance to or exit from a parking lot are usually operated by ticket dispensing, card reading, or vehicle sensing devices in the pavement. In normal operation, the gates raise to permit only one vehicle to pass at a time lowering after the vehicle has passed. However, due to accident or otherwise, a gate may descend when a vehicle is located directly underneath. In such case, the wooden arm strikes the vehicle with damage to both vehicle and gate arm. Sensing devices located underneath and along the length of the wooden arm adapted to reverse the gate are vulnerable to damage along with the gate arm as when the parking gate arms are broken off by vehicles driving through when the arm is lowered.

SUMMARY OF THE INVENTION The present invention comprises a pair of crank arms located on the shaft about which the parking gate arm pivots with a spring loaded lost motion connection therebetween. The master crank is rigidly fastened to the shaft and the other slave crank may rotate about the shaft and is pivotally connected at its other end to a connecting rod which in turn is driven by a third crank, transmission and reversible motor. The slave crank may rotate about the shaft only through a few degrees of lost motion with respect to the master crank. This rotation is limited by stops mounted on the master crank. When the slave crank is rotated against one stop, the shaft is then forced to turn with the slave crank and the parking gate arm is raised. Rotation of the slave crank in the other direction is limited by a spring loaded lost motion stop and the parking gate arm is rotated downward. If the parking gate arm strikes an object, the spring is compressed and a limit switch immediately signals the associated controls to reverse the motor and raise the arm.

DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic view of the actuating mechanism,

FIG. 2 is a plan view of the safety mechanism,

FIG. 3 is a side view of the safety mechanism, and

FIG. 4 is a schematic view of the electrical control including the safety control.

DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 a shaft is supported by bearings 12 and is mounted inside a parking gate cabinet 11 shown in dotted outline through which one end extends to a flange 13 upon which the parking gate arm 15 is mounted. On the shaft are mounted two

cams

14 and 16 which actuate

switches

18 and 20. These switches, 18 and 20, signal the raised and lowered gate arm positions to the control shown in FIG. 4. The shaft 10 is rotated by a safety crank assembly shown generally by 22 and which in turn is driven by connecting rod 24 to which the safety crank assembly is pivoted at 26. The connecting rod 24 is driven by a crank 25, transmission 28, drive belt 30 and reversible electric motor 32.

The safety crank assembly 22 is more particularly shown in FIGS. 2 and 3. Welded to the shaft 10 is a master crank 34 which rotates with the shaft and the parking gate arm. Adjacent the master crank 34 is a slave crank 36 which rotates about a journal bearing 38 mounted on the shaft 10. Mounted on the master crank 34 is a stop 40 upon which the slave crank 36 may abut at 42. A hole 44 is shown in the slave crank 36 for the pivot 26 also shown in FIG. 1. The slave crank 36 is thus driven by the connecting rod 24 in FIG. 1, and when the slave crank is driven against the stop 40 at 42 the master crank 34 and shaft 10 are forced to rotate with the slave crank 36 and the parking gate arm rotates upwardly.

A second stop 46 is mounted on the master crank 34 and carries on it a spring member 48 which can contact the slave crank 36 at 50. Upon rotation of the slave crank 36 in the other direction by the connecting rod 24 the slave crank 36 contacts the spring 48 at 50 thus causing the master crank 34 and shaft 10 to rotate oppositely and lower the parking gate arm. The spring 48 is sufficiently stiff and preloaded to prevent deflection during normal operation. If, as the parking gate arm is lowering, an obstruction is encountered, the shaft 10 and master crank 34 will stop and the spring 48 will be deflected against the still rotating slave crank 36. A switch 52 is mounted on a bracket 54 which in turn is mounted on the master crank 34. The relative movement of the slave crank 36 with respect to the master crank 34 will actuate the switch and the control shown in FIG. 4 will reverse the electric motor 32. The connecting rod 24 will reverse and cause the slave crank 36 to rotate oppositely against stop 40 at 42 thereby raising the gate. The switch 52 contacts the :slave crank 36 with a spring mounted contact 56 which in this case extends to actuate the switch when the spring 48 is sufficiently deflected.

In FIG. 4 a control circuit for the safety gate mechanism is shown. An automatic or manual operation switch 60 is provided whereby in manual mode the gate will open and remain open. The dashed circuits in the automatic portion denoted open and close pertain to the circuits associated with whatever means are utilized to signal the gate such as a ticket dispenser or a vehicle sensing device. In automatic mode and when the circuit designated open is actuated, relay R-2 is energized and remains energized thus causing the circuit 62 to be closed and the motor 32 to raise the gate. Upon reaching the upper most position, the cam operated switch 20 energizes circuit 64 and de-energizes circuit 66 thus shutting off the motor 32. Circuit 64 energizes relay R-3 disconnecting circuit 68 at the top. The gate is now ready to lower. Upon completion of the circuit designated close, the relay R-l is energized, the other portion of the circuit 70 for raising the gate is broken, and the circuit designated 72 for lowering the gate remains broken. The signal from the circuit designated close is only momentary and upon breaking, circuit 72 is completed and the motor 32 operates in the reverse direction to lower the gate until the lower most position is reached whereupon the cam actuated switch 18 will break circuit 72.

In the event that an obstruction is encountered by the gate before the lower most position is reached, the switch 52 in the safety crank assembly 22 will be actuated and circuit 74 completed to energize relay R-2. Relay R-2 will break circuit 72 and complete circuit 62 to reverse the motor 32 and raise the gate. The circuit 74 is connected up through the cam operated switch 18 to break circuit 74 when the gate is in its lower most position. This is to prevent the gate from being actuated to raise merely by lifting on the end of the arm when it is fully down.

I claim:

1. An automatic parking gate mechanism adapted to raise and lower a barrier gate, a rotatable lost motion drive connection in said mechanism comprising a driving arm and a driven arm mounted with a common axis of rotation and a resilient drive means therebetween adapted for deflection in response to interruption in the downward movement of said gate, and means responsive tosaid deflection for raising said gate.

2. The automatic parking gate mechanism of claim 1 including means responsive to said gate reaching its normal barrier position for deactivating said means responsive to said deflection.

3. The automatic parking gate mechanism of claim 1 wherein said resilient drive means bias said lost motion drive connection to a normal position which may be overcome by a predetermined resistance to said downward movement.

4. An automatic parking gate mechanism having a rotatable shaft, bearing means supporting said shaft, a reversible motor driven crank assembly including a reversible motor driven crank means for rotation of said shaft, and control means actuated by said shaft to limit the angular rotation of said shaft, the improvement comprising; a master crank attached to said shaft, a slave crank adjacent said master crank and rotatable about said shaft, said slave crank being pivoted to said reversible motor driven crank means to thereby rotate said slave crank about said shaft in either direction, a deflectable stop attached to said master crank and engageable with said slave crank whereby upon engagement said master crank and shaft will rotate with said slave crank and lower a parking gate arm and whereby a lowering parking gate arm upon striking an obstruction will stop said master crank and shaft thereby deflecting said deflectable stop, safety switch means engageable with said slave crank and actuated upon deflection of said deflectable stop, said safety switch means being connected to said control means to reverse said motor driven crank means thus raising said parking gate arm.

Claims

1. An automatic parking gate mechanism adapted to raise and lower a barrier gate, a rotatable lost motion drive connection in said mechAnism comprising a driving arm and a driven arm mounted with a common axis of rotation and a resilient drive means therebetween adapted for deflection in response to interruption in the downward movement of said gate, and means responsive to said deflection for raising said gate.

5. The automatic parking gate mechanism of claim 4 wherein said deflectable stop includes a spring.

6. The automatic parking gate mechanism of claim 4 including a stop attached to said master crank and engageable with said slave crank whereby upon engagement said master crank and shaft will rotate with said slave crank to raise a parking gate arm.

7. The automatic parking gate mechanism of claim 4, including means for deactivating said safety switch means responsive to said parking gate arm reaching its normal lowered position.