WO1991002599A1

WO1991002599A1 - A liquid spraying apparatus

Info

Publication number: WO1991002599A1
Application number: PCT/DK1990/000215
Authority: WO
Inventors: Arne Andersen; Jens Petersen
Original assignee: K/S EPOKE VEJMASKINER
Current assignee: K/S EPOKE VEJMASKINER
Priority date: 1989-08-21
Filing date: 1990-08-21
Publication date: 1991-03-07
Anticipated expiration: 1992-02-21
Also published as: AU6332890A

Abstract

A liquid spraying apparatus for a road machine with a spraying bar (1), a plurality of spray nozzles being provided along said spraying bar. The liquid spraying apparatus is connected to a container supplying spraying liquid by means of a pump. According to the invention, the pump (7) is connected to a speed-sensing drive wheel (11) through a gear so as to provide a speed-dependent dosing of spraying liquid.

Description

Title: A Liquid Spraving Apparatus

Technical Field

The invention relates to a liquid spraying apparatus with a spraying bar and a plurality of spray nozzles provided along said spraying bar, ' said apparatus comprising a container supplying spraying liquid to the spraying bar by means of a pump.

Background Art

Road machines spraying dissolved salt are preferred to road machines spraying powdered salt because the powdered salt is spread by passing vehicles. As a result an optimal salt effect cannot be achieved. In addition the dissolved salt has an accelerating effect on the dissolving and melting of ice on the roads.

DK-PS No. 144,863 discloses a mechanism adjusting a hy¬ draulic driving motor so as to synchronize the movement of a vehicle provided ;ith a gravel scattering apparatus. The adjustment mechanism comprises means transferring the varying movement so as to obtain a rotation of a threaded control means. The control means engages an axially immov¬ able threaded means in a threaded manner, whereby said threaded means can be axially moved. The movable control means is connected to an adjustment valve for the hydraulic motor in such a manner that the speed of rotation of the output shaft thereof depends on the position of the control means on the axially immovable means. The output shaft of tue motor is connected to the axially immovable threaded means in such a manner that said immovable threaded means is turned in the same direction as the control means during the rotation of the output shaft. The control means is con¬ nected to one end of a roller chain extending over a manoeuvring wheel for the adjustment valve. Such an adjust- ment mechanism is, however, relatively complicated and expensive.

Disclosure of the Invention

The object of the invention is to provide a liquid spraying apparatus which is less complicated than the previously known apparatuses.

A spraying apparatus of the above type comprises a wheel pump connected through a possible gear to a speed-sensing drive wheel so as to provide .a dosing of the spraying liquid which is substantially proportional to the speed. In this manner a spraying apparatus is obtained which is much less complicated than the previously known apparatu¬ ses .

An electronically controlled valve may be activated when the speed of rotation exceeds a predetermined value, whereby spraying liquid can be supplied to further nozzles on the bar.

In addition, a further wheel pump may discharge spraying liquid through side nozzles, and the side nozzles may be activated by means of an electronically controlled valve blocking a return line of the further wheel pump.

The spray nozzle may advantageously comprise a spring- loaded piston for closing and opening the discharge orifice more or less in response to the liquid pressure on the piston, the spring being dimensioned in such a manner that the liquid is discharged at a substantially constant speed irrespective of the liquid pressure.

In this manner the spring-loaded piston causes a drop in pressure in the discharge orifice with the result that the liquid is discharged at the same speed when it hits the curved stop wall. Furthermore, the liquid is discharged at the same angle and equally far out irrespective of the flow. The drop in pressure causes the discharged liqid to hit the stop wall at a constant speed, and accordingly, the spreading angle is not influenced by the amount of liquid. The distribution is not influenced either because the liquid hits the entire wall. The curved stop wall ensures a uniform spreading of the liquid over the entire spreading angle.

Moreover the stop wall may according to the invention be substantially circular.

Furthermore, the nozzle opening may according to the invention be conical and adapted to provide a spray angle of approximately 40".

Brief Description of Drawings

The invention is described in greater detail below with reference to the accompanying drawings , in which

Fig. 1 illustrates a spraying apparatus in form of a trailer with a spraying bar and a plurality of spray nozzles along said spraying bar,

Fig. 2 illustrates a filter inserted in the trailer,

Figs. 3 and 4 the pumps in question and the associated valves ,

Fig. 5 a linear motor connecting and disconnecting the pumps ,

Fig. 6 a gear transferring the power from the driving wheel , Fig. 7 the control panel in question,

Fig. 8 a diagrammatic illustration of the spraying appa¬ ratus ,

Fig. 9 is a bottom view of a longitudinally and transverse- ly sectional view through the spraying nozzle according to the invention,

Fig. 10 illustrates the operation of the spray nozzle in connection with large and small flows, respectively,

Figs. 11 and 12 illustrate an alternative embodiment of a spray nozzle, and

Fig. 13 is a diagrammatic illustration of an alternative embodiment of the spraying apparatus.

Best Mode for Carrying Out the Invention

According to the invention, a road machine is provided for a speed-dependent spreading of dissolved salt over a road. An advantage of a salt solution is that it does not disappear so quickly when a vehicle is passing. Furthermore the solution has an accelerating effect on the dissolving and melting of the ice on the road.

Fig. 1 shows a spraying apparatus in form of a trailer for a truck. The trailer comprises a spraying bar 1, a plurality of spray nozzles (not shown) being provided along said bar 1. The trailer is connected to a container on the truck body, said container supplying the spraying liquid. The spraying liquid is supplied through a hose 2 extending to the rearmost portion of the trailer and therethrough. Subsequently, the liquid continues through a further hose 3 placed along the rearmost upper rim of the trailer inside said trailer, and further downwards to a filter 4 in the bottom of the trailer. The filter 4 is provided with a screen removable from the outside through the right side wall of the trailer. Then the filtered liquid goes through two hoses 5 , 6 to each pump 7, 8, cf. Fig. 4, said hoses extending along the upper rear rim of the trailer. The pumps 7, 8 comprise a common driving shaft 9. Through a friction clutch 10, cf. Fig. 5, and a chain gear in a separate chamber on the outside of the trailer, cf. Fig. 6, the driving shaft 9 is connected to the shaft of a speed-sensing drive wheel 11, i.e. the left wheel, so as to produce a speed-dependent dosing of the spraying liquid. The right pump 7 feeds the spraying bar 1 with spraying liquid. Two hoses 21, 22 originate from the pump 7, said two hoses extending through the inclining bottom surface 23 c the trailer. One of the hoses contains an electronic valve 24 being activated and opened when the speed of rotation of the pump 7 exceeds a predetermined value (approximately 135 rpm . Subsequently, spraying liquid can be fed to further nozzles on the spraying bar 1. A return line 3 is provided in connection with the pump 7 in case of cloggings in the system. One¬ way valves 3? 33 are inserted in the hoses extending to the spraying bar 1, said one-way valves being placed on the spraying bar, cf. Fig. 1.

The second pump 8 supplies side nozzles 14 in the left side of the spraying bar 1 with sprayin liquid. The liquid is supplied through a hose connected to the discharge stub of the pump 8. The hose is connected to a T piece 36 secured to a supporting plate between two brackets 37, 38. The T piece 36 is connected to an electronic valve 40, said electronic valve being activated when the speed of rotation exceeds a predetermed value (approximately 135 rpm) . The hose from the T piece 36 and the valve 40, respectively, extends to the side nozzles 14. The side nozzles 14 are activated by means of a second electronic valve 15 blocking a return line for the second pump 8, said return line being connected to the hose 3. The elec¬ tronic valves are preferably of the type Taulignon 26230. The pumps with the common driving shaft 35 are mechanically connected and disconnected by means of a G.V. friction clutch. In connected state, the friction clutch is com¬ pletely free of contact and frictional heat is accordingly avoided in the no-load position. All the movable members are subjected to wear and tear and are therefore hardened with the result that the durability of the friction clutch is extended. The hardening applies to a release ring, an arm, a two-part ring, a pressure ring and a pressure plate. A particular detail of such a coupling is that the release ring is arranged in a ball bearing. The hub follows the turning of the inner ring of the release ring, whereby running-hot and wear and tear are avoided. The following of the inner ring is obtained by means of a spring ring secured against twisting. The spring ring acts simultan¬ eously as a security lock for the release ring after the connection.

The ball bearing is sealed and contains sufficient lubri¬ cant for the entire life of the component and an inspection is therefore not required.

The three easily removable arms are made of stainless bars. They abut and center towards a ring. At the connec- tion, the points of the pressed down lifting arms are provided with a shape of radius, which mates the abutment surfaces on the hub of the inner ring. As a result, the pressure on the angular arm Is very uniformly transferred. Simultaneously, the angular arm takes over the function of a tripple-hardened wedge connection between the hub and the pressure ring, said pressure ring having a shock- absorbing effect due to the angular arm bars. Accordingly, the G.V. friction clutch is suited for irregular transfer of power. The pressure plate between the short arm and the pressure ring prevents a wear and tear of the pressure r in

The clutch 10 is controlled by a linear motor 18 through an arm 17, said motor 18 also being secured to the inclin¬ ing bottom surface 23. The linear motor 18 is connected to a control panel through an electric cable 19, cf. Fig. 7, said control panel being placed in the cab of the truck where it is inserted in the lighter current output in the car. The control panel indicates furthermore the amount of supplied liquid.

Manually operated gear couplings are provided in connection with the transfer of power from the drive wheel, i.e. the left wheel, four gears being present. The handles 12, 13 for the gear couplings are placed on the outer side.

The pumps are preferably membrane pumps of the type AR 230 from Annovi Reverberi.

All the hoses are reliably secured by means of strong hose clamps .

The wheels of the trailer have been placed as far back as possible so as to ensure stability.

A support wheel is placed at the front portion of the trailer, said support wheel being used when the trailer is not used.

A tension rod is provided and can be coupled to the truck.

Fig. 8 is a diagrammatic illustration of the liquid spray- ing apparatus. The turning movement of the drive wheel 11 is transferred through chain wheels and gear couplings to a rotary shaft. The rotary shaft can be connected to the driving shaft of the membrane pumps 8 and 7 through the clutch 10. The pump 7 pumps liquid directly to the small nozzles In the spraying bar 1. Liquid can furthermore be pumped to large nozzles in the spraying bar 1 by means of a selecting valve in form of an electromotor-controlled valve 24. A counter-acting valve 32 is placed in front of the small nozzles in the spraying bar 1, said counter¬ acting valve not being opened until the pressure is 0.9 bar. A counter-acting valve 33 is placed in front of the large nozzle in the spraying bar 1, said counter-acting valve 33 not being opened until the pressure is 1.5 bar. A safety valve is provided in connection with the pump 7, said safety valve opening a return line at a pressure of 5 bar.

The second pump 8 is connected to the side nozzles 14 through a second selecting valve in form of an electromotor valve 15. A counter-acting valve is placed in front of the small side nozzles, said counter-acting valve not opening until the pressure is 0.9 bar. A selecting valve in form of an electromotor-controlled valve and a counter¬ acting valve are placed in front of the large side nozzles, said counter-acting valve not opening until the pressure is 1.5 ar . A safety valve is provided for the pump 8 so as to ensure a return flux in case of cloggings in the system.

According to the invention, a spray nozzle is provided, cf. Fig. 9, which ensures a desired spray pattern, prefer¬ ably a desired discharge angle independent of the amount of discharged liquid. The spray nozzle comprises a nozzle casing with an inlet channel 51 connected to a substantial¬ ly radially oriented discharge orifice 52. The discharge orifice 52 is conical. The inlet channel 51 contains a movable spring-loaded piston 53 closing and opening the discharge orifice 52 more or less in response to the liquid pressure on the piston 53. The spring 54 is dimensioned in such a manner that the liquid is discharged at a sub- stantially constant speed irrespective of the liquid pressure in the inlet channel 51. The abutment wall 52a. for the liquid in the discharge orifice 52 is furthermore substantially oval, whereby a uniform spreading of the liquid being discharged is obtained inside a predermined angle, such as for instance 40° . The nozzle opening is preferably conical with a cone angle of 40° . The nozzle is for instance placed on the side of the spraying appa¬ ratus in such a manner that it can spread approximately 3.5 m to the neighboring traffic lane. A plurality of nozzles are also provided on the bottom side of the spray¬ ing bar. The same spraying angle can be obtained irrespec¬ tive of the amount of discharged liquid and the speed of the vehicle. The liquid is preferably an NaCl solution or a CaCl2 solution. The spring 54 causes a drop in pressure across the discharge orifice. The drop in pressure ensures that the liquid hits the abutment wall 52a. at a substan¬ tially constant speed. As a result, the spreading angle is substantially unaffected by the amount of liquid. The slower the flow is the more the piston 53 is retracted with the result that the liquid is spread. The area of the piston 53 is approximately 1.54 cm^ and the piston opens at a pressure of approximately 1.23 kg* (1.23 bar). Fig. 9 shows a stop cylinder 55 for the piston 53 and a sealing ring 56 of elastomeric material. A compression of the spring from 32 to 25 cm requires approximately 1.25 kg*.

Previously used nozzles depended on a constant flow for maintaining the desired spreading angle.

Figs. 11 and 12 show an alterr .tive embodiment of a spray nozzle. The spray nozzle comprises a nozzle body 61 and an outer flap 62 of elastomeric material, said flap cover¬ ing the nozzle orifice 63. A piston rod 64 acts on the outer flap 62 through a pivotally mounted linked bar 65 comprising a pin 66. One link of the linked bar is perma- nently connected to the outer side of the nozzle body. The piston rod 64 is activated through a hose 66 connected to the pressure side of the nozzle. The hose 66 is connec¬ ted to a housing containing a pressure-sensitive membrane 68, the piston rod 64 being secured to said membrane. The 5 membrane 68 is furthermore activated by a spring 69 inside the housing 67. As a result, the spring 69 inside the housing 67 moves the piston rod 64 and consequently the flap 62 of elastomeric material downwards towards the nozzle orifice 63 so as to close said orifice 63. A supply

10 of pressure through the hose 66 causes the membrane 68 inside the housing 67 to move upwards whereby the orifice is opened more or less in response to the liquid pressure on the membrane 68 and the piston rod 64 secured thereto. The linked bar is acted on by the piston rod 64, and it

15 is horseshoe-shaped with a pin 70 pressing on the rubber flap 62, said elastomeric flap being placed on the outside of the nozzle body 61. The spring presses on the membrane with the result that the piston rod 64 is retracted and the elastomeric flap 62 is pressed downwards towards the

20 obliquely cut orifice 63 of the nozzle body. The elasto¬ meric flap 62 is retained by means of small screws and covers a subs antially pear-shaped orifice 63 in the nozzle body. A circular opening of approximately 3 mm has at the end been widened by means of a bevelling of approximately

25 45° , said oval opening being covered by the elastomeric flap 62. When the liquid is under pressure and cannot pass the nozzle orifice due to the elastomeric flap 62, said liquid flows downwards through the hose 66 so as to act on the membrane 68 inside the housing. As a result, the

30 spring 69 is compressed and starts lifting the rubber flap 62 in such a manner that the liquid can be discharged. In this manner a substantially constant jet is obtained.

Fig. 13 is a diagrammatic illustration of an alternative embodiment of the spraying apparatus according to the

35 invention. The spraying apparatus comprises a drive wheel

76, i.e. the left wheel of the trailer, driving a wheel pump 78 through a gear 77. The wheel pump 68 drives a hydraulic motor 73 through an adjustment valve 75, said hydraulic motor 73 driving by means of a gear 72 some pumps 71 for the liquid to be discharged through the nozzle. In order to allow an adjustment of the amount of discharged liquid, the hydraulic motor 73 must be adjust¬ able inside a relatively large dynamic range. This is rendered possible by means of a tachometer 74 mounted on the output shaft and the hydraulic motor 74, said tachome- ter measuring the Instantaneous speed of rotation. The signal from the tachometer 74 is transmitted to an elec¬ tronic circuit comparing said speed of rotation with the adjusted amount and the speed of the spraying apparatus (detected at 74). The electronic circut adjusts the oil flow through the valve 75 so as to achieve the desired speed of rotation of the hydraulic motor 73.

Claims

Claims .

1. A spraying apparatus with a spraying bar and a plura¬ lity of spray nozzles provided along said spraying bar, said apparatus comprising a container supplying spraying liquid to the spraying bar by means of a pump, c h a r¬ a c t e r i s e d in that it comprises a wheel pump con¬ nected through a possible gear to a speed-sensing drive wheel so as to provide a dosing of the spraying liquid which is substantially proportional to the speed.

2. A spraying apparatus as claimed in claim 1, c h a r¬ a c t e r i s e d in that an electronically controlled valve is activated when the speed of rotation exceeds a predetermined value, whereby spraying liquid can be sup¬ plied to further nozzles on the bar.

3. A spraying apparatus as claimed in claim 1 or 2, c h a r a c t e r i s e d in that a further wheel pump discharges spraying liquid through side nozzles.

4. A spraying apparatus as claimed in claim 3, c h a r¬ a c t e r i s e d in that the side nozzles are activated by means of an electronically controlled valve blocking a return line of the further wheel pump.

5. A spraying apparatus as claimed in the preceding claims l to 4, c h a r a c t e r i s e d by a safety return line for each wheel pump in case of cloggings in the system.

6. A spraying apparatus with a spraying bar, where a plurality of spray nozzles are provided along said spraying bar, said apparatus comprising a container supplying spraying liquid by means of a wheel pump, said pump through a possible gear being connected to a speed-sensing drive wheel so as to provide a dosing of the spraying liquid, c h a r a c t e r i s e d in that the spray nozzle com¬ prises a spring-loaded piston for closing and opening the discharge orifice more or less in response to the liquid pressure on the piston, the spring (54) being dimensioned in such a manner that the liquid is discharged at a substantially constant speed irrespective of the liquid pressure.

7. A spraying apparatus as claimed in claim 6, c h a r¬ a c t e r i s e d in that the stop wall (52a.) of the liquid being discharged is substantially oval.

8. A spraying apparatus as claimed in claim 6 or 7, c h a r a c t e r i s e d in that the stop wall is sub¬ stantially circular.

9. A spraying apparatus as claimed in the preceding claims 6 to 8, c h a r a c t e r i s e d in that the nozzle orifice is conical.

10. A spraying apparatus as claimed in claim 6, c h r¬ a c t e r i s e d in that the spray nozzle comprises a spring-loaded piston (64) for closing and opening the discharge orifice more or less in response to the liquid pressure on the piston (64) and by way of a flap (62) of elastomeric material.

11. A spraying apparatus as claimed in claim 10, c h a r a c t e r i s e d in that the piston acts on the outer flap (62) through a pivotally mounted linked rod (65) with a pin (66) acting on the flap (62).

12. A spraying apparatus as claimed in claim 11, c h a r a c t e r i s e d in that the piston is activated through a separate hose (66) connected to the pressure side of the nozzle.

13. A spraying apparatus as claimed in claim 12, c h a r a c t e r i s e d in that the hose (66) is con¬ nected to a housing (67) containing the spring (69) , one end of said spring (69) being connected to a pressure- sensitive membrane (68) inside said housing (67).

14. A spray nozzle for producing a desired spray pattern, preferably a desired discharge angle, and comprising a nozzle casing with an inlet channel connected to a substan¬ tially radially oriented outlet opening, said inlet channel comprising a movable spring-loaded piston closing and opening the discharge orifice more or less in response to the liquid pressure on the piston, c h a r a c t e r¬ i s e d in that the spring is dimensioned in such a manner that the liquid is discharged at a substantially constant speed irrespective of the liquid pressure, and that the stop wall of the liquid being discharged is substantially oval.

15. A spray nozzle as claimed in claim 14, c h a r a c¬ t e r i s e d in that the stop wall of the nozzle orifice is substantially circular.

16. A spray nozzle as claimed in claim 14, c h a r a c¬ t e r i s e d in that the nozzle orifice is conical.

17. A spray nozzle as claimed in claim 16, c h a r a c¬ t e r i s e d in that the conical nozzle orifice is adapted to provide a spray angle of approximately 40° .

18. A spray nozzle as claimed in the preceding claims 14 to 17, c h a r a c t e r i s e d in that it comprises a spring-loaded pistion (64) closing and opening the dis¬ charge orifice (63) more or less in response to the liquid pressure on the piston and by way of a flap (62) of elasto¬ meric material.

19. A spray nozzle as claimed in claim 18, c h a r a c¬ t e r i s e d in that the piston (64) acts on the outer flap (62) through a pivotally arranged linked rod provided with a pin (66) acting on said flap (62).

20. A spray nozzle as claimed in claim 18 or 19, c h a r a c t e r i s e d in that the piston (64) is activated through a separate hose (66) connected to the pressure side of the nozzle.

21. A spray nozzle as claimed in claim 20, c h a r a c- t e r i s e d in that the hose (66) is connected to a housing (67) containing the spring (69), one end of said spring being connected to a pressure-sensitive membrane (68) inside the housing (67).