US1666508A - Yieldable barrier - Google Patents
Yieldable barrier Download PDFInfo
- Publication number
- US1666508A US1666508A US639366A US63936623A US1666508A US 1666508 A US1666508 A US 1666508A US 639366 A US639366 A US 639366A US 63936623 A US63936623 A US 63936623A US 1666508 A US1666508 A US 1666508A
- Authority
- US
- United States
- Prior art keywords
- columns
- shaft
- barrier
- roadway
- gear
- 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
Links
- 230000004888 barrier function Effects 0.000 title description 29
- 238000010276 construction Methods 0.000 description 12
- 125000006850 spacer group Chemical group 0.000 description 12
- 230000007246 mechanism Effects 0.000 description 8
- 230000033001 locomotion Effects 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000003028 elevating effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 238000005192 partition Methods 0.000 description 1
- 238000007634 remodeling Methods 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B61—RAILWAYS
- B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
- B61L29/00—Safety means for rail/road crossing traffic
- B61L29/02—Guards or obstacles for preventing access to the route
Definitions
- My invention relates to certain novel and useful improvements in yieldable barriers and has for its principal object the provision of an improved construction of this character which will be highly efficient in use and economical in manufacture.
- the present invention constitutes an-improvement over that disclosed in my application filed in the United States Patent Office on or about December 27, 1921, Serial No. 525,236.
- the present invention relates especially to the driving mechanism for elevating and lowering the spacer boxes within the columns and the construction is of such nature that the spacer boxes will move in unison with a single overhead drive shaft connected as a unit with other parts of the driving mechamsm.
- the novel construction ofthe columns including'columns rectangular in cross section as well as cylindrical columns and the con struction is of such nature that the columns may be mounted on each side of road ways regardless of whether side walk arms are to be associated withv the barrier or not, the constructions of the columns being such that at any time after erection of the columns the side Walk arms and mechanism for op erating the same can afterwards he installed without remodeling or reconstructing the columns.
- Fig. 1' is an elevational view of the yield able barrier embodying the invention
- FIG. 2 is a. typical fragmentary sectional view of the lower ends of the columns and taken substantially on line 22-of Fig. 3;
- Fig. 3 is a. fragmentary sectional view taken substantially on line 33 of Fig. 2;
- Fig. 4 is a'sectional view taken substan tially on line 44 of Fig. 2;
- Fig. 5 is a typical fragmentary lower end view of the columns showing a modified form of construction
- Fig. dis a sectiona-l'view taken substantially on line 6- 6 of Fig, 5.
- the columns 10. and 10 are mounted on each side of a road way along which the vehicle to be stopped passes and arranged an appreciable distance below the caps 16 is a structure indicated at 17 carrying suitable bearings 18.
- the structure 17 can be arranged to carry the overhead trolley wires as indicated at 19.;
- a housing 20 within which a motor 21 is arranged and controlled by a. circuit breaker 22 including a circuit breakerarm 23.
- the shaft of the motor 21 carries a gear 24 which operatively meshes with a gear 25 mounted on a shaft 26 carrying a worm gear 27 arranged in a housing 28-forming an integral part of a base 29 and provided with a vertically extending bracket 30.
- gear 31 meshes. with the worm gear. 27 and is keyed to. a shaft 32 mounted in bearings 33 and 34 the latter forming an integral part of the bracket 30.
- a sprocket gear 35 operatively connected to a sprocket gear 36 by a sprocket chain 37 the sprocket gear .36 being mounted for free rotation on a stationary shaft 38- at the upper end of the column housing the driving mechanism above.
- the bearings 18 carry an overhead shaft 39 extending between thecolumns with its ends extending into the interior thereof.
- the interior end 40 of the shaft 39 carries a.”
- sprocket'chain 46 a sprocket gear 43 forming an integral part of asprocket gear 47 mounted on a I shaft 48 at the upper endof the column 10.
- a sprocket gear 49 mounted'on ashaft 50 and operatively connected to the sprocket gear 47 by a sprocket chain 51.
- the shaft 50 carries a gear similar to the gear indicated at 56 for operative relation with themoeh- (iii anism for lowering and raising the side walk arm to be hereinafter mentioned;
- the construction so far disclosed provides a driving arrangement which accomplishes the object of the invention for raising and lowering the spacer boxes within the columns in unison at a steady and even movement. It can be readily seen that there is a disadvantage in providing a motor for moving the spacer boxes independently of each other as will be readily understood and that it will be a very diflicult thing to time the motors so that the same would operate at the same time and in unison.
- the spacer boxes are indicated at 52 and are arranged for movement in the compartments 12 and carry reserve members 53 operatively connected to the barrier 54' which is adapted to extend across the roadway and be moved upwardly and downwardly between the columns 10 and 10.
- the spacer boxes are incorporated in the sprocket chains mounted in suitable bearings 57 and carries a worm gear 58 for operative meshed relation with a segment gear 59 fixed to a shaft 60.
- each column is cylindrical in shape and has a cast base 69 forming an integral part thereof or bolted thereto, and the column is designed in such manner that the same can be used with or without the side walk arms.
- each column in this instance is made from a plate or elongated sheet of metal rolled or bent into cylindrical form with a gap oropening at one side to permit the passage of the reserve members and the vertical movement thereof. This con stitutes a stron and rigid construction for the purpose ma c all in one piece and therefore capable of economical construction.
- a housing indicated at 68. in dotted lines can be attached to the column for housing the driving mechanism of the side walk arm to be associated therewith as herein referred to.
- each of the columns is especially provided to receive a counter weight indicated at 68' which is usedin connection with recoiling the reserve members 53 within the spacer boxes and for the construction of such mechanism reference is to be had to my pending application above referred to. f
- a device of the class described comprising columns at oppositesides of the roadway, an impact receiving member extending across the roadway and mounted to move vertically on said columns, a transverse shaft extending between said columns, a motor at the base of one of said columns, an operative connection between said motor, the corresponding end of said impact member and said transverse shaft, and an operative connection between said transverse shaft and the other end of said impact member.
- a device of the class described comprising columns at opposite sides of the roadway, an impact receiving member ex tending across the roadway and mounted to move vertically on said columns, a cross frame between said columns and located well above said roadway, a transverse shaft mounted on said cross frame and extending between said columns, a motor at the base of one of said columns, an operative connection between said motor, the corresponding end of said impact member and said transverse shaft, and an operative connection between said transverse shaft and the other end of said impact member.
- a device of the class described com prising columns at opposite sides of the roadway, spacer members mounted to movevertically in said columns, an impact receiv ing member mounted on said spacer members, a transverse shaft extending between said columns above said roadway, sprocket wheels on said shaft and operating in said columns, a motor at the base of one of said columns, a sprocket chain connection between said motor, said transverse shaft and the spacer member in the corresponding column, and a sprocket chainconnection between the other spacer member and the corresponding sprocket wheel on said transverse shaft.
- a device of the class described including hollow columns arranged on each side of a road way along which a vehicle is adapted to pass, an impact receiving member extending across the roadway between the columns, means movably mounted within the columns and carrying the impact receiving members, unyieldable barriers including a transverse shaft movably carried by the columns, and means for moving the impact member carrying means and the unyieldable barriers in unison.
- a device of the class described including hollow columns on each side of a roadway along which vehicles are adapted to pass, a barrier extending across the roadway between the columns, means movably mounted in the columns and carrying the barrier, a driving element at the foot of one of the columns, an overheaddriving element extending across the roadway between the columns, operative connections between the driving elements and the carrying means, unyieldable barriers movably carried by the columns and adapted to extend across the side walks on the opposite sides of the roadway, and an operative connection between the unyieldable barriers and the driving elements whereby the unyieldable barriers will move in unison with the carrying means.
- a device of the class described including hollow columns arranged on each side of a roadway, a yieldable barrier extending across the roadway between the columns, unyieldable barriers movably carried by the columns and extending across the side walks on the opposite sides of the roadway, driving means at the foot of one of the columns, a shaft an appreciable distance below the top of the columns and extending across the roadway, gear and sprocket chain arrangements within the columns affording an operative connection between the driving means, the carrying means, the unyieldable barriers and the drive shaft.
- a barrier column consisting of a plate bent into substantially tubular form with a gap at one side providing a longitudinal opening, and a transverse member adapted to divide said column into two compart-' ments.
- a column for barriers consisting of a plate bent into substantially tubular form having a gap at one side providing a longitudinal opening, and a plate arranged transversely of said column and dividing the same into two compartments.
- a device of the class described comprising a two compartment column adapted in cooperation with another column to support a yielding barrier; a shaft mounted in the wall of said columnand extending from the interior to the exterior thereof, means con-- tained in said column for operating said shaft; and a. sidewalk arm detachably mounted on the outer end of said shaft.
Description
April 17, 1928. 1,666;508
E. D. SAWYER YIELDABLE BARRIER Filed May 16, 1923 3 Sheetg-Sheet 1 April 17, 1928. 1,666,508
E. D. SAWYER YIELDABLE BARRIER Filed May 16, 1925 3 Sheets-Sheet 2 17/1/1250 0i1/%er April 17, 1928. 1,666,508
' E. D. SAWYER YIELDABLE BARRIER Filed May 16. 1923 3 Sheets-Sheet 3 OQQQ OOOGO w g y 74711 5545 1271/01/02:
ff/arzr y Patented Apr. 17, 1928.
UNITED STATES EMERSON D. SAWYER, OF CHICAGO, ILLINOIS,
' YIELDABLE. BARRIER.
. Application filed May 16,
My invention relates to certain novel and useful improvements in yieldable barriers and has for its principal object the provision of an improved construction of this character which will be highly efficient in use and economical in manufacture. The present invention constitutes an-improvement over that disclosed in my application filed in the United States Patent Office on or about December 27, 1921, Serial No. 525,236.
The present invention relates especially to the driving mechanism for elevating and lowering the spacer boxes within the columns and the construction is of such nature that the spacer boxes will move in unison with a single overhead drive shaft connected as a unit with other parts of the driving mechamsm.
Among other. objectsof the invention is the novel construction ofthe columns including'columns rectangular in cross section as well as cylindrical columns and the con struction is of such nature that the columns may be mounted on each side of road ways regardless of whether side walk arms are to be associated withv the barrier or not, the constructions of the columns being such that at any time after erection of the columns the side Walk arms and mechanism for op erating the same can afterwards he installed without remodeling or reconstructing the columns.
Other objectswill appear hereinafter.
The invention consists in the combinations and arrangements of parts hereinafter described and claimed.
The invention willbe best understood by reference to the accompanying drawings forming a part of this specification, and in which, L
Fig. 1' is an elevational view of the yield able barrier embodying the invention;
2 is a. typical fragmentary sectional view of the lower ends of the columns and taken substantially on line 22-of Fig. 3;
Fig. 3 is a. fragmentary sectional view taken substantially on line 33 of Fig. 2;
Fig. 4 is a'sectional view taken substan tially on line 44 of Fig. 2;
Fig. 5 is a typical fragmentary lower end view of the columns showing a modified form of construction; and
Fig. dis a sectiona-l'view taken substantially on line 6- 6 of Fig, 5.
Referringto Fig. 1, 10 and 10 mdlcate 1923. Serial No. 639,366.
suitable footings 11, and divided intocom-- partments 12 and 13 by a partition 14and provided with a longitudinally extending opening 15. The columns 10. and 10 are mounted on each side of a road way along which the vehicle to be stopped passes and arranged an appreciable distance below the caps 16 is a structure indicated at 17 carrying suitable bearings 18. When the columns are mountedat each side'of a road way along which a street car is adapted to pass, the structure 17 can be arranged to carry the overhead trolley wires as indicated at 19.;
At the foot of one of the columns is arranged a housing 20 within which a motor 21 is arranged and controlled by a. circuit breaker 22 including a circuit breakerarm 23. The shaft of the motor 21 carries a gear 24 which operatively meshes with a gear 25 mounted on a shaft 26 carrying a worm gear 27 arranged in a housing 28-forming an integral part of a base 29 and provided with a vertically extending bracket 30. A
' eratively connect-ed bya sprocket'chain 46 to a sprocket gear 43 forming an integral part of asprocket gear 47 mounted on a I shaft 48 at the upper endof the column 10. At the lower end of the column 10' is-a sprocket gear 49 mounted'on ashaft 50 and operatively connected to the sprocket gear 47 by a sprocket chain 51. The shaft 50 carries a gear similar to the gear indicated at 56 for operative relation with themoeh- (iii anism for lowering and raising the side walk arm to be hereinafter mentioned;
The construction so far disclosed provides a driving arrangement which accomplishes the object of the invention for raising and lowering the spacer boxes within the columns in unison at a steady and even movement. It can be readily seen that there is a disadvantage in providing a motor for moving the spacer boxes independently of each other as will be readily understood and that it will be a very diflicult thing to time the motors so that the same would operate at the same time and in unison.
The spacer boxes are indicated at 52 and are arranged for movement in the compartments 12 and carry reserve members 53 operatively connected to the barrier 54' which is adapted to extend across the roadway and be moved upwardly and downwardly between the columns 10 and 10. The spacer boxes are incorporated in the sprocket chains mounted in suitable bearings 57 and carries a worm gear 58 for operative meshed relation with a segment gear 59 fixed to a shaft 60. Adjacent one end of the segment gear 59 and connected eccentrically there to as at 61 is an adjustable link 62 having its free end pivoted as at 63 to a rocker arm 64 fixed to a shaft 65 extending through a bearing 66 and carrying at its exterior end the side walk arm 67 constituting an unyieldable barrier. 7
By the selective provision and arrangement of the segmental gear and the adjustable link during the downward move ment of the side walk arms when 'the driving mechanism is in operation the arms increase'in speed until a point indicated at A is reached atfwhich time the speed of the arms decreases until the bottom is reached. The advantages of this arrangement are such that upon operation of the side wall: arms if one should accidently be beneath the arms when the same are in the act of being lowered the side walk arms will not suddenly come down upon the person therebeneath and thereby injure him, but at a point such as indicated at A the arms are slackened and the person thereunder has time to move aside to prevent being hit by the arms or injured if hit. A further advantage of this arrangement, is such that side walk arms as has been found in cases where a chain is incorporated as a driving unit in the driving mechanism for driving the arms. 1
in connection with the mechanism for driving the side walkarms 1 mount on the shaft 60 extending into the motor housing an arm 66 having a pin 67 at its extremity operatingon the breaker arm 23. This arrangement is such that by the time the side walk arms and barrier 5% are lowered in the position illustrated in Fig. 1 the circuit controlling the motor 21 will be cut out automatically when the side walk arms and barrier reach a pre-determined position.
As shown in Figs. 5 and 6 each column is cylindrical in shape and has a cast base 69 forming an integral part thereof or bolted thereto, and the column is designed in such manner that the same can be used with or without the side walk arms. As will be noted each column in this instance is made from a plate or elongated sheet of metal rolled or bent into cylindrical form with a gap oropening at one side to permit the passage of the reserve members and the vertical movement thereof. This con stitutes a stron and rigid construction for the purpose ma c all in one piece and therefore capable of economical construction. In case it is desired or in case it is required that a side walk army be associated with the barrier, provision is made whereby a housing indicated at 68. in dotted lines can be attached to the column for housing the driving mechanism of the side walk arm to be associated therewith as herein referred to.
The compartment 13 of each of the columns is especially provided to receive a counter weight indicated at 68' which is usedin connection with recoiling the reserve members 53 within the spacer boxes and for the construction of such mechanism reference is to be had to my pending application above referred to. f
It is apparent from the foregoing description that I provide certain improvements in yieldable barriers which have many advantages over the barriers of'the class now commercially in use and that it will be apparent by those skilled in the art that when the overhead shaft is operated, the spacer boxes and barrier 54 will move upwardly or down wardly with ease and in unison at an economical cost; I
l Vhile I have illustrated and described the preferred form of construction for carrying my invention into effect, this is capable of variation and modification without departing from the spirit of the invention. l
therefore, do not wish to be limited to the Jii ion
precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.
Having described my invention what I claim as new and desire to secure by Letters Patent is:
1. A device of the class described comprising columns at oppositesides of the roadway, an impact receiving member extending across the roadway and mounted to move vertically on said columns, a transverse shaft extending between said columns, a motor at the base of one of said columns, an operative connection between said motor, the corresponding end of said impact member and said transverse shaft, and an operative connection between said transverse shaft and the other end of said impact member.
2. A device of the class described comprising columns at opposite sides of the roadway, an impact receiving member ex tending across the roadway and mounted to move vertically on said columns, a cross frame between said columns and located well above said roadway, a transverse shaft mounted on said cross frame and extending between said columns, a motor at the base of one of said columns, an operative connection between said motor, the corresponding end of said impact member and said transverse shaft, and an operative connection between said transverse shaft and the other end of said impact member.
3. A device of the class described com prising columns at opposite sides of the roadway, spacer members mounted to movevertically in said columns, an impact receiv ing member mounted on said spacer members, a transverse shaft extending between said columns above said roadway, sprocket wheels on said shaft and operating in said columns, a motor at the base of one of said columns, a sprocket chain connection between said motor, said transverse shaft and the spacer member in the corresponding column, and a sprocket chainconnection between the other spacer member and the corresponding sprocket wheel on said transverse shaft.
4. A device of the class described including hollow columns arranged on each side of a road way along which a vehicle is adapted to pass, an impact receiving member extending across the roadway between the columns, means movably mounted within the columns and carrying the impact receiving members, unyieldable barriers including a transverse shaft movably carried by the columns, and means for moving the impact member carrying means and the unyieldable barriers in unison.
5. A device of the class described including hollow columns on each side of a roadway along which vehicles are adapted to pass, a barrier extending across the roadway between the columns, means movably mounted in the columns and carrying the barrier, a driving element at the foot of one of the columns, an overheaddriving element extending across the roadway between the columns, operative connections between the driving elements and the carrying means, unyieldable barriers movably carried by the columns and adapted to extend across the side walks on the opposite sides of the roadway, and an operative connection between the unyieldable barriers and the driving elements whereby the unyieldable barriers will move in unison with the carrying means.
6. A device of the class described including hollow columns arranged on each side of a roadway, a yieldable barrier extending across the roadway between the columns, unyieldable barriers movably carried by the columns and extending across the side walks on the opposite sides of the roadway, driving means at the foot of one of the columns, a shaft an appreciable distance below the top of the columns and extending across the roadway, gear and sprocket chain arrangements within the columns affording an operative connection between the driving means, the carrying means, the unyieldable barriers and the drive shaft.
7. A barrier column consisting of a plate bent into substantially tubular form with a gap at one side providing a longitudinal opening, and a transverse member adapted to divide said column into two compart-' ments. v
8. A column for barriers consisting of a plate bent into substantially tubular form having a gap at one side providing a longitudinal opening, and a plate arranged transversely of said column and dividing the same into two compartments.
9. A device of the class described comprising a two compartment column adapted in cooperation with another column to support a yielding barrier; a shaft mounted in the wall of said columnand extending from the interior to the exterior thereof, means con-- tained in said column for operating said shaft; and a. sidewalk arm detachably mounted on the outer end of said shaft.
In testimony whereof I have signed my name to this specification.
EMERSON D. SAVVYER.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US639366A US1666508A (en) | 1923-05-16 | 1923-05-16 | Yieldable barrier |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US639366A US1666508A (en) | 1923-05-16 | 1923-05-16 | Yieldable barrier |
Publications (1)
Publication Number | Publication Date |
---|---|
US1666508A true US1666508A (en) | 1928-04-17 |
Family
ID=24563800
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US639366A Expired - Lifetime US1666508A (en) | 1923-05-16 | 1923-05-16 | Yieldable barrier |
Country Status (1)
Country | Link |
---|---|
US (1) | US1666508A (en) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050211389A1 (en) * | 2004-03-25 | 2005-09-29 | Snyder Ronald P | Retractable safety barrier |
US20060124252A1 (en) * | 2004-12-14 | 2006-06-15 | Rite-Hite Holding Corporation | Vertically movable door with safety barrier |
US20060137261A1 (en) * | 2004-12-14 | 2006-06-29 | Rite-Hite Holding Corporation | Alarm system for a loading dock |
US20080127435A1 (en) * | 2004-12-14 | 2008-06-05 | Paul Maly | Alarm system for a loading dock |
US8087443B2 (en) | 2007-07-06 | 2012-01-03 | Rite-Hite Holding Corporation | Retractable safety barriers and methods of operating same |
US8590087B2 (en) | 2004-12-14 | 2013-11-26 | Rite-Hite Holding Corporation | Lighting and signaling systems for loading docks |
US11697910B2 (en) | 2019-08-21 | 2023-07-11 | Rite-Hite Holding Corporation | Impact resistant retractable safely barriers |
-
1923
- 1923-05-16 US US639366A patent/US1666508A/en not_active Expired - Lifetime
Cited By (20)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7207370B2 (en) | 2004-03-25 | 2007-04-24 | Rite-Hite Holding Corporation | Retractable safety barrier |
US20050211389A1 (en) * | 2004-03-25 | 2005-09-29 | Snyder Ronald P | Retractable safety barrier |
US7337822B2 (en) | 2004-03-25 | 2008-03-04 | Rite-Hite Holding Corporation | Retractable safety barrier |
US20060191644A1 (en) * | 2004-03-25 | 2006-08-31 | Snyder Ronald P | Retractable safety barrier |
US20060213626A1 (en) * | 2004-03-25 | 2006-09-28 | Rite-Hite Holding Corporation | Retractable safety barrier |
US7237591B2 (en) | 2004-03-25 | 2007-07-03 | Rite-Hite Holding Corporation | Retractable safety barrier |
US20080127435A1 (en) * | 2004-12-14 | 2008-06-05 | Paul Maly | Alarm system for a loading dock |
US20110000626A1 (en) * | 2004-12-14 | 2011-01-06 | Miller Jason D | Vertically movable door with safety barrier |
US20060137261A1 (en) * | 2004-12-14 | 2006-06-29 | Rite-Hite Holding Corporation | Alarm system for a loading dock |
US7380375B2 (en) | 2004-12-14 | 2008-06-03 | Rite-Hite Holding Corporation | Alarm system for a loading dock |
US20060124252A1 (en) * | 2004-12-14 | 2006-06-15 | Rite-Hite Holding Corporation | Vertically movable door with safety barrier |
US7775252B2 (en) | 2004-12-14 | 2010-08-17 | Rite-Hite Holding Corporation | Vertically movable door with safety barrier |
US7832451B2 (en) | 2004-12-14 | 2010-11-16 | Rite-Hite Holding Corporation | Vertically movable door with safety barrier |
US20070079942A1 (en) * | 2004-12-14 | 2007-04-12 | Snyder Ronald P | Vertically movable door with safety barrier |
US8590087B2 (en) | 2004-12-14 | 2013-11-26 | Rite-Hite Holding Corporation | Lighting and signaling systems for loading docks |
US8453705B2 (en) | 2004-12-14 | 2013-06-04 | Rite-Hite Holding Corporation | Vertically movable door with safety barrier |
US8547234B2 (en) | 2004-12-14 | 2013-10-01 | Rite-Hite Holding Corporation | Alarm system for a loading dock |
US8490668B2 (en) | 2007-07-06 | 2013-07-23 | Rite-Hite Holding Corporation | Retractable safety barriers and methods of operating same |
US8087443B2 (en) | 2007-07-06 | 2012-01-03 | Rite-Hite Holding Corporation | Retractable safety barriers and methods of operating same |
US11697910B2 (en) | 2019-08-21 | 2023-07-11 | Rite-Hite Holding Corporation | Impact resistant retractable safely barriers |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US1666508A (en) | Yieldable barrier | |
US1203006A (en) | Apparatus for stopping vehicles. | |
US1819866A (en) | Tamping and rolling machine operated by vibration | |
US2346388A (en) | Gate drive | |
GB891975A (en) | Paving material spreader | |
US2141953A (en) | Crossing gate structure | |
CN108049330A (en) | A kind of urban road safety height-limiting device | |
US2194650A (en) | Door operating mechanism | |
US1634854A (en) | Electric elevator | |
US1953677A (en) | Apparatus for exterminating the ground mole | |
US2082610A (en) | Hedge trimmer | |
US2231177A (en) | Ballast cribbing machine | |
CN213836412U (en) | Multifunctional prompting device for road surface collapse | |
US1823596A (en) | Railroad crossing gate | |
US1419357A (en) | Operating mechanism for mine doors | |
US1594281A (en) | Automobile signal | |
US1668625A (en) | Arrangement for lifting the wheels of vehicles | |
CN209070739U (en) | A kind of follow-on traffic control suggestion device | |
US1866752A (en) | Lifeguard or obstruction remover for motor road and other vehicles | |
US1240096A (en) | Gate-operating device. | |
US1666780A (en) | Locomotive mover | |
US1147714A (en) | Automobile-jack. | |
US1091984A (en) | Railway-track-tamping machine. | |
US1725505A (en) | Warning signal for railroad crossings | |
SU583232A1 (en) | Apparatus for removing snow from road surface |