GB1571018A

GB1571018A - Display cabinets

Info

Publication number: GB1571018A
Application number: GB581577A
Authority: GB
Original assignee: Linde GmbH
Current assignee: Linde GmbH
Priority date: 1976-02-11
Filing date: 1977-02-11
Publication date: 1980-07-09
Also published as: IT1115701B; SE7701388L; ES455797A1; FR2340702A1; DE2605352A1; FR2340702B3

Description

(54) IMPROVEMENTS IN OR RELATING TO DISPLAY CABINETS (71) We, LINDE AKTIENGESELL SCHAFT, a German Company, of Abraham Lincoln-Strasse 21, D-62 Wiesbaden, German Federal Republic, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: The present invention relates to a display cabinet, such as a refrigerated sales counter, having a casing for storing and displaying foodstuffs, and a front panel hinged to the casing so that the panel can be raised and lowered.

Such display cabinets are normally installed when the goods offered for sale, for instance, meat, fish or cheese, have to be presented to the client for inspection without it being possible for the client to touch them. To permits inter alia, access to the interior of the casing the front panel is hinged to the casing in a manner to permit the panel to be lifted upwards. The hinge devices comprise spring means and are so constructed that after passing through a dead centre point of the spring means, the front panel is pulled against an upper or lower abutment by forces exerted by the hinge device. When the panel is being closed, the force created by the weight of the panel through the spring element in the vicinity of the lower abutment in addition to the resetting force of the spring means is, however, particularly disadvantageous.In certain cases, the front panel can be pulled against the lower abutment with such power that it fractures.

An object of the invention is to provide a display cabinet in which the front panel can be safely lifted and lowered in a simple manner, without the exertion of any particular force, and this especially in the vicinity of the lower abutment.

Accordingly, this invention consists in a display cabinet comprising a casing and a panel hinged to the casing by means of a hinge device thereby to permit the panel to be moved between a closed position and an open posi tion, said hinge device comprising:--a toggle lever carrying the panel and being pivotably mounted at a first pivot point fixed with res pect to the casing, a compression spring, one end of which is pivotably mounted at a second pivot point fixed with respect to the casing, the other end of the spring being pivotably mounted on the toggle lever at a third pivot point spaced from the first pivot point, said third pivot point lying, in the closed position of the panel, substantially on a line through the first and second pivot points.

Thus in any position of the front panel the compression spring will act against the re setting moment resulting from the weight of the panel. With a given geometry and weight of the panel, the pressure force of the spring means can be so selected in relation to the effective lever length of the hinge device that the resetting moment is wholly or partly neu tralised at certain positions of the front panel.

The pressure force of the spring means can also be so selected, however, that at given opening angles the front panel is automatically swung upwards. A reinforcement of the resetting moment resulting from the weight of the front panel through the spring element is excluded, since the lower dead centre of the hinge device is not passed. If the pivoting axes of the hinge means lie on one line when the front panel is closed, i.e. the common pivot axis of spring means and the toggle lever is located precisely in the lower dead centre, then the closing of the front panel will be effected exclusively through its own weight.

In a particularly advantageous manner, the spring means has an at least approximately constant pressure force. This requirement is for example fulfilled by a pneumatic spring. A pneumatic spring consists essentially of a cylinder, a piston having a plurality of plates penetrated by apertures, a piston rod and sealing and fixing components. The swept volumes of the pneumatic spring are in communication with one another through the aper tures in the piston and are charged with gas under pressure. In this way a constant force acts upon the piston which pushes the piston rod out. If the cylinder is partly filled with a liquid, for instance oil, then the ejection speed of the pneumatic spring can be subjected to a terminal damping, as soon as the oil passes through the apertures in the piston instead of gas.The outward or inward feeding movement of the piston rod can be damped, according to the choice and disposition of the apertures in the plates of the piston.

It has proved to be desirable in particular for a pneumatic spring with terminal damping if the spring element is always disposed with its front end inclined downwards, whatever the position of the front panel may be.

In the case of one preferred display cabinet the spring means is disposed in an associated casing of U-shaped cross section and connected to supports at both ends. The support disposed at the control side of the display cabinet is bent over at its upper end and fixed rigidly to the rear end of the casing, for example by welding.

At its lower end the supports are fixed to the sub-structure of the cabinet which supports the actual body thereof, for instance by bolt ing. A support disposed on the side of the cabinet on which customers are intended to stand joins the front end of the casing to the body of the cabinet in an exchangeable and adjustable manner. The casing and front and rear supports fixed to it lie in one plane. In this way a twisting of the casing and thus of the whole structure is avoided. The casing can consequently simultaneously serve as a car rier for a cash box or till, which terminates the structure horizontally at the top.

An exemplary embodiment of the invention will now be described in more detail with reference to the accompanying schematic drawings, in which: Figures 1 is a cross-sectional view of a dis play cabinet constructed in accordance with the invention; and Figure 2 is a sectional view of a hinge de vice forming part of the display cabinet.

Figure 1 is a cross-sectional view of a re frigerated dislay cabinet constructed in ac cordance with the invention. The cabinet has a base 1 carrying a chest 2. The base 1 com prises a plurality of rectangular steel tubes, Shaped in section, joined together to form a robust and sturdy structure. A rear support 4 extends obliquely inwardly from one side of the cabinet to a casing 5, in which the hinge devices are arranged. The casing 5, which may also serve as a support surface for a cash box or till 6, is supported at its edge remote from the support 4 by means of a support 7, which also extends obliquely and inwardly from the chest 2. The support 7 can be ex changeable and adjustable in its length.The cabinet is covered at the front thereof by a front panel 8, which is made of transparent material such as glass and which is pivotable about an upper pivot axis. The front panel 8 is shown in its closed position, in which it rests against a lower abutment (not referenced).

When occupying its closed position, the panel will slope rearwardly. The open-position of the front panel 8 is shown in broken line, the panel in this position resting against an upper abutment. Each front panel may be provided with two or more hinge devices, depending upon the length and weight of the panels. The hinge devices are conveniently joined one to the other through profile section rails 9.

Figure 2 is a sectional view of a hinge device used on the cabinet shown in Figurel. The casing 5 comprises a length of profiled material of U-shaped cross-section and is disposed transversely to the longitudinal axis of the chest 2. The rear support 4 joins the casing 5 at its rear end. Casing 5 and the rear support 4 can have the same breadth and may be welded together to form one component. At its front end the casing 5 is supported by the front support 7. In the illustrated embodiment the casing 5 is joined to the front support 7 by means of a bracket 10 to the open under side of the casing. In order to enable the front panel 8 to be swung freely about its hinges, the side walls of the casing 5 are cut away, at the front ends thereof.

In the illustrated embodiment, the compression spring means of the hinge device comprises piston-cylinder arrangement 12, in which the cylinder 18 thereof is sealed and filled with a pressurized gas, such as air, the pressure of said gas being higher than the ambient pressure. One end 17 of the cylinder is pivotally mounted to the casing by a pin 11, while one limb of a toggle lever 14 is pivotally mounted on a fixed pin 13 carried on the front end of the casing 5. Arranged for reciprocating movement in the cylinder 18 is a piston rod 19, the end of which piston remote from the pin 11 is pivotally connected to the toggle lever 14 by a pin 15 remote from the pin 13. The toggle lever 14 and with it the front panel 8 can be pivoted about the pin 13. The front panel 8 is fixed to the toggle lever 14 through a U-shaped rail 16.

The position of the front panel 8 and the toggle lever 14 at the upper abutment point is shown in broken line. The end 17 of the cylinder has the form of a tongue and together the pin 11 forms a rear pivot support for the spring element 12. The piston rod is pivotally mounted to the pin 15 through an eye 20, the pin 15 forming a common pivot point for the piston-cylinder arrangement and toggle lever 14. The piston of the piston-cylinder-arrangement 12 is comprised mainly of three discs.

A central disc 21 seals against the walls of the cylinder and has a central bore whose diameter is greater than that part of the piston rod on which it is seated, so that an annular gap exists between the disc 21 and the piston rod 19. As will be seen from Figure 2, the piston rod has a length of reduced diameter on which the discs are seated. The two remaining discs 22 and 23 are apertured, such that the sum of the diameters of the apertures of the disc 22 abutting the stepped face of the piston rod is greater than that of the other disc 23 ar ranged at the end of the piston rod 19 remote from the pin 15. The discs 22 and 23 are fixed rigidly to the piston rod 19. The distance between the two discs 22 and 23 is greater than the thicknes of the central disc 21. The volumes 24 and 25 of the cylinder swept by the piston are filled with gas under pressure.

Some oil 26 is provided in a swept volume 26 of the cylinder, this oil providing a terminal damping of the movement of the piston rod after a given amount of outward movement. As shown, the piston-cylinder arrangement is arranged in a manner such that it will slope downwardly towards the support 7 in all positions of the panel 8. In the embodiment illustrated, the front panel is at its lower abutment point. In this position the pins 11, 15 and 13 lie on a straight line. In no position of the front panel 8 does the pin 15, which moves in a circular path around the pin 13, pass the line joining the pins 11 and 13. In this way it is ensured that the pressure force exerted by the spring means will always exert a moment countering the resetting moment resulting from the weight of the front panel 8.When the front panel 8 is closed, no moment resulting from the pressure force of the spring means 12 will act upon it. The front panel 8 is only held closed by its own weight.

If the front panel 8 is swung upwards, the piston rod 19 is moved out of the cylinder 18. Gas will then flow through the apertures of the disc 22 and through the apertures of the disc 23 from the cylinder portion referenced 25 to the cylinder portion referenced 24, but will not flow around the outside of the disc 23, since the disc 21 lies against the disc 23 so as to block the passage of gas between the periphery of the disc and the cylinder wall when the front panel 8 is opened to an extent such that all the remaining cylinder space down-stream of the discs 23, 21, 22 is filled with oil, terminal damping will begin, whereby the front panel can only be moved slowly to its upper abutment point.

When closing the front panel 8 the piston rod 19 is moved back into the cylinder 18.

Simultaneously gas flows through the apertures of the disc 23 and the annular gap between disc 23 and cylinder 18 and also through the apertures of the disc 22 from the cylinder space 24 into the cylinder space 25. The pneumatic spring is thus damped on the outward movement, since the throttling effect of the discs 21, 22, 23 is greater when the piston rod is moved outwards than when moved inwards.

The pressure force of the spring is advantageously so selected in relation to the weight and the geometry of the front panel and also to the effective lever arm of the lifting fitting, that from a given opening angle, for example 10 to 15 , the front panel 8 swings upwards automatically, or practically automatically. As will be understood, the pressure acting on the end of the piston rod adjacent the disc 23 will be far greater than the pressure acting on the end of the piston rod protruding from the sealed cylinder.

WHAT WE CLAIM IS:- 1. A display cabinet comprising a casing and a panel hinged to the casing by means of a hinge device thereby to permit the panel to be moved between a closed position and an open position, said hinge device com prising: -a toggle lever carrying the panel and being pivotally mounted at a first pivot point fixed with respect to the casing, a compression spring, one end of which is pivotably mounted at a second pivot point fixed with respect to the casing, the other end of the spring being pivotably mounted on the toggle lever at a third pivot point spaced from the first pivot point, said third pivot point lying, in the closed position of the panel, substantially on a line through the first and second points.

2. A display cabinet as claimed in Claim 1, wherein the spring exerts an at least approximately constant pressure force.

3. A display cabinet as claimed in Claim 1 or Claim 2, wherein the end of the spring connected to the toggle is lower than the other end of said spring in all positions of the panel.

4. A display cabinet as claimed in any one of the preceding claims, wherein the spring is arranged in a housing of U-shaped cross-section connected to the casing at each end by respective support members.

5. A display cabinet as claimed in any one of the preceding Claims, wherein the compression spring has the form of a piston-cylinder-arrangement comprising a gas-tight cylin-.

der filled with a gas which is pressurized to a pressure higher tlian the ambient pressure, and a piston arranged on a piston rod for reciprocating movement in the cylinder, one end of the cylinder being pivotally attached to said first casing member and the end of the piston remote from said first casing mem ber being freely connected to the toggle by said moveable pivot pin.

6. A display cabinet as claimed in Claim 5, wherein the end of the piston remote from the moveable pivot pin is provided with piston damping means.

7. A display cabinet as claimed in Claim 6, wherein the damping means comprises a first perforated disc fixedly arranged on the piston rod coaxially therewith and a second perforated disc fixedly mounted on the piston rod and spaced axially from the first perforated disc,

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **.

exists between the disc 21 and the piston rod 19. As will be seen from Figure 2, the piston rod has a length of reduced diameter on which the discs are seated. The two remaining discs 22 and 23 are apertured, such that the sum of the diameters of the apertures of the disc 22 abutting the stepped face of the piston rod is greater than that of the other disc 23 ar ranged at the end of the piston rod 19 remote from the pin 15. The discs 22 and 23 are fixed rigidly to the piston rod 19. The distance between the two discs 22 and 23 is greater than the thicknes of the central disc 21. The volumes 24 and 25 of the cylinder swept by the piston are filled with gas under pressure.

Some oil 26 is provided in a swept volume

26 of the cylinder, this oil providing a terminal damping of the movement of the piston rod after a given amount of outward movement. As shown, the piston-cylinder arrangement is arranged in a manner such that it will slope downwardly towards the support 7 in all positions of the panel 8. In the embodiment illustrated, the front panel is at its lower abutment point. In this position the pins 11, 15 and 13 lie on a straight line. In no position of the front panel 8 does the pin 15, which moves in a circular path around the pin 13, pass the line joining the pins 11 and 13. In this way it is ensured that the pressure force exerted by the spring means will always exert a moment countering the resetting moment resulting from the weight of the front panel 8.When the front panel 8 is closed, no moment resulting from the pressure force of the spring means 12 will act upon it. The front panel

8 is only held closed by its own weight.

If the front panel 8 is swung upwards, the piston rod 19 is moved out of the cylinder 18. Gas will then flow through the apertures of the disc 22 and through the apertures of the disc 23 from the cylinder portion referenced 25 to the cylinder portion referenced 24, but will not flow around the outside of the disc 23, since the disc 21 lies against the disc 23 so as to block the passage of gas between the periphery of the disc and the cylinder wall when the front panel 8 is opened to an extent such that all the remaining cylinder space down-stream of the discs 23, 21, 22 is filled with oil, terminal damping will begin, whereby the front panel can only be moved slowly to its upper abutment point.

When closing the front panel 8 the piston rod 19 is moved back into the cylinder 18.

Simultaneously gas flows through the apertures of the disc 23 and the annular gap between disc 23 and cylinder 18 and also through the apertures of the disc 22 from the cylinder space 24 into the cylinder space 25. The pneumatic spring is thus damped on the outward movement, since the throttling effect of the discs 21, 22, 23 is greater when the piston rod is moved outwards than when moved inwards.

The pressure force of the spring is advantageously so selected in relation to the weight and the geometry of the front panel and also to the effective lever arm of the lifting fitting, that from a given opening angle, for example 10 to 15 , the front panel 8 swings upwards automatically, or practically automatically. As will be understood, the pressure acting on the end of the piston rod adjacent the disc 23 will be far greater than the pressure acting on the end of the piston rod protruding from the sealed cylinder.

WHAT WE CLAIM IS:- 1. A display cabinet comprising a casing and a panel hinged to the casing by means of a hinge device thereby to permit the panel to be moved between a closed position and an open position, said hinge device com prising: -a toggle lever carrying the panel and being pivotally mounted at a first pivot point fixed with respect to the casing, a compression spring, one end of which is pivotably mounted at a second pivot point fixed with respect to the casing, the other end of the spring being pivotably mounted on the toggle lever at a third pivot point spaced from the first pivot point, said third pivot point lying, in the closed position of the panel, substantially on a line through the first and second points.
2. A display cabinet as claimed in Claim 1, wherein the spring exerts an at least approximately constant pressure force.
3. A display cabinet as claimed in Claim 1 or Claim 2, wherein the end of the spring connected to the toggle is lower than the other end of said spring in all positions of the panel.
4. A display cabinet as claimed in any one of the preceding claims, wherein the spring is arranged in a housing of U-shaped cross-section connected to the casing at each end by respective support members.
5. A display cabinet as claimed in any one of the preceding Claims, wherein the compression spring has the form of a piston-cylinder-arrangement comprising a gas-tight cylin-.

der filled with a gas which is pressurized to a pressure higher tlian the ambient pressure, and a piston arranged on a piston rod for reciprocating movement in the cylinder, one end of the cylinder being pivotally attached to said first casing member and the end of the piston remote from said first casing mem ber being freely connected to the toggle by said moveable pivot pin.
6. A display cabinet as claimed in Claim 5, wherein the end of the piston remote from the moveable pivot pin is provided with piston damping means.
7. A display cabinet as claimed in Claim 6, wherein the damping means comprises a first perforated disc fixedly arranged on the piston rod coaxially therewith and a second perforated disc fixedly mounted on the piston rod and spaced axially from the first perforated disc,

the diameters of which discs are smaller than the diameter of the cylinder, and a third disc arranged between said first and second discs, the diameter of the third disc being equal to the diameter of the cylinder and having a central bore whose diameter is greater than the diameter of the piston rod.
8. A display cabinet as claimed in Claim 7, wherein the total perforated area of one fixed disc is greater than the total perforated area of the other fixed disc.
9. A display cabinet substantially as hereinbefore described with reference to, and as illustrated in, Figure 1 and Figure 2 of the drawings.