Control arm having adjustable length

Abstract

The invention relates to a control arm for joining a flap holder to a flap, folding flap, door, or the like in an articulated manner, the control arm comprising at least one first and one second telescoping arm displaceably guided thereon for adjusting the length thereof, and the control arm comprising at least one fixing device for fixing the position of the two telescoping arms relative to each other. It is thereby provided that a detent connection acting between the telescoping arms in the direction of the change in length thereof is associated with the control arm and comprises at least two detent settings disposed along the change in length of the control arm and spaced apart by a detent spacing.

The invention further relates to a lifting device having such a control arm and a method for adjusting the length of such a control arm.

The length of the control arm can be easily and quickly adjusted to the particular flap, folding flap, door, or the like.

Claims

1-25. (canceled)

26: A control arm for joining a flap holder to a flap of an item of furniture in an articulated manner, the control arm comprising: a first telescoping arm; a second telescoping arm displaceably guided on the first telescoping arm for adjusting a length of the control arm; a fixing device configured to fix a position of the first and second telescoping arms relative to each other; and a detent connection between the first and second telescoping arms, the detent connection including at least two detent settings disposed along the length of the control arm and spaced apart by a detent spacing.

27: The control arm of claim 26, wherein: successive detent settings are each disposed at the same detent spacing from each other.

28: The control arm of claim 27, wherein: the detent spacing has a whole-number ratio to a spacing of potential installed positions of the flap holder on the item of furniture.

29: The control arm of claim 27, wherein: the detent spacing is 8 mm.

30: The control arm of claim 26, wherein: the detent connection includes a plurality of detent receptacles disposed on one of the first and second telescoping arms; and the detent connection includes a spring-loaded detent element configured to engage the detent receptacles.

31: The control arm of claim 30, wherein: the fixing device is configured to lock the detent element in one of the detent receptacles.

32: The control arm of claim 30, wherein: the fixing device includes a locking element engaging with one of the detent receptacles in a first operating position and disengaging from the one detent receptacle in a second operating position.

33: The control arm of claim 32, wherein: the locking element produces a locking connection to the other of the first and second telescoping arms in both operating positions.

34: The control arm of claim 30, wherein: the locking element is spaced from the detent element by the detent spacing or by a whole-number multiple of the detent spacing.

35: The control arm of claim 30, wherein: the first telescoping arm is an outer telescoping arm and the second telescoping arm is an inner telescoping arm received in the outer telescoping arm; and the detent receptacles are disposed on the inner telescoping arm.

36: The control arm of claim 35, wherein: the inner telescoping arm includes a groove extending in a longitudinal direction, and the detent receptacles are disposed on a floor of the groove.

37: The control arm of claim 35, wherein: the inner telescoping arm includes a groove extending in a longitudinal direction, at least one of the detent connection and the fixing device being disposed at least partially in the groove.

38: The control arm of claim 37, wherein: the fixing device includes a locking element engaging with one of the detent receptacles in a first operating position and disengaging from the one detent receptacle in a second operating position; and a T-nut is guided in the groove, at least one of the detent element and the locking element being disposed on the T-nut.

39: The control arm of claim 38, wherein: the detent element includes a spring-loaded detent pin linearly displaceably guided in a pin guide on the T-nut.

40: The control arm of claim 38, wherein: the detent element includes an elastic spring detent protrusion including a detent head, the elastic spring detent protrusion being integrally formed with the T-nut.

41: The control arm of claim 38, wherein: the locking element of the fixing device includes a locking screw threaded into the T-nut and including a screw end engaging with one of the detent receptacles at a first operating thread-in depth and disengaging from the detent receptacle at a second operating thread-in depth.

42: The control arm of claim 41, wherein: the locking screw includes a screw head accessible at both operating thread-in depths from outside the control arm through a locking hole defined in the outer telescoping arm.

43: The control arm of claim 42, wherein: the T-nut includes a screw receptacle implemented as a through hole, the locking screw being threaded into the screw receptacle, the screw receptacle including an enlarged region configured to receive the screw head.

44: The control arm of claim 26, wherein: the first telescoping arm includes an attachment region at an end of the first telescoping arm facing away from the second telescoping arm, the attachment region being configured to be placed over a mounting protrusion of a pivotably supported lever of the flap holder.

45: A lifting device including the control arm of claim 25 in combination with the flap holder and with a flap bearing configured to be attached to the flap, the control arm being connected to the flap holder and to the flap bearing.

46: The lifting device of claim 45, wherein: the flap holder includes a pivotably supported lever including a mounting protrusion, the first telescoping arm of the control arm being attached to the mounting protrusion, the flap holder further including a fixing screw threaded into the mounting protrusion such that when the fixing screw is fully threaded-in the fixing screw is disengaged from a fixing hole on the first telescoping arm, and when the fixing screw is partially threaded-in the fixing screw is engaged with the fixing hole.

47: The lifting device of claim 46, wherein: the fixing screw includes a head having a stop and a fixing segment adjacent the stop, and when the fixing screw is partially threaded into the mounting protrusion the stop bears upon the first telescoping arm and the fixing segment engages with the fixing hole.

48: The lifting device of claim 45, wherein: the flap bearing includes a pivot bearing connected to the control arm, the flap bearing being configured to provide continuously variable linear adjustment of a position of the pivot bearing relative to the flap.

49: A method of adjusting a length of a control arm of a lifting device for a flap of an item of furniture, the control arm providing a pivotable connection between a flap holder attached to a furniture frame and a flap bearing attached to the flap, the control arm including a first telescoping arm and a second telescoping arm displaceably guided on the first telescoping arm to adjust a length of the control arm, the control arm including a fixing device configured to fix a position of the first and second telescoping arms relative to each other, the control arm including a detent connection configured to provide successive detent settings between the first and second telescoping arms, the method comprising: closing the flap with the fixing device in an open position such that the length of the control arm is adjusted to a required length and the detent connection detents into one of the detent settings; opening the flap with the length of the control arm being maintained by the detent connection; and fixing the length of the control arm with the fixing device while the flap is open.

50: The method of claim 49, further comprising: displacing a coupling point of the control arm on the flap bearing relative to the flap to tune the closed position of the flap.

Description

[0035] The invention is explained in greater detail below using an embodiment example shown in the drawings. They show:

[0036] FIG. 1 An item of furniture having a folding flap joined by a hinge and a lifting device having a control arm,

[0037] FIG. 2 A perspective side view of the control arm,

[0038] FIG. 3 A plan view of a segment of the control arm,

[0039] FIG. 4 An exploded view of a segment of the control arm

[0040] FIG. 5 A partial section side view of the control arm,

[0041] FIG. 6 A side section view of a segment of the control arm,

[0042] FIG. 7 A side section view of the item of furniture shown in FIG. 1 having the folding flap joined by a hinge, the lifting device, and the control arm, and

[0043] FIG. 8 A side section view of a segment of the control arm.

[0044] FIG. 1 shows an item of furniture 10 having a folding flap joined by a hinge and a lifting device having a control arm 40. The item of furniture 10 is implemented here as a wall cupboard. The furniture frame comprises a side wall 11, a rear wall 12, a cabinet top 13, and a cabinet floor 14. A mounting element 20 for attaching the item of furniture, for example to a wall, is disposed on the side wall 11. The interior space of the item of furniture 10 is subdivided by a shelf 15. To this end, front and rear wall holes 16.1, 16.2 are made in the side wall 11 and in a second side wall of the item of furniture disposed opposite the side wall 11 and not shown. Mounting elements, not shown, on which the shelf 15 rests are disposed in one each front and rear wall hole 16.1, 16.2. The front and rear wall holes 16.1, 16.2 are spaced apart from each other at a fixed, specified hole spacing 17. The hole spacing 17 is standardized and here is 32 mm.

[0045] The item of furniture 10 can be closed by means of the folding flap shown partially opened here. The folding flap comprises a first and a second partial flap 18, 19. The two partial flaps 18, 19 are connected to each other by means of a central hinge 22. The first partial flap 18 is hinged to the furniture frame by means of a furniture hinge 21 and attached there to the cabinet top 13.

[0046] The lifting device supports the opening and closing operation of the folding flap. Said device is implemented here for holding the folding flap in position even in a partially open condition. To this end, said device comprises a flap holder 30 attached to the side wall 11 of the item of furniture 10. The flap holder 30 is fixed at at least one of the front wall holes 16.1. The installed position of the flap holder 30 can be selected depending on the size of the item of furniture 10 and the folding flap. The potential installed positions are thereby specified by the locations of the front wall holes 16.1. A housing 32 of the flap holder 30 shown in FIG. 7 is obscured by a cover 31 in the representation according to FIG. 1. A mounting protrusion 33.1 extends out of the housing 32. As can be seen further in FIG. 7, the holding protrusion 33.1 is part of a lever 33 pivotably supported on the flap holder 30. One end of the control arm 40 is connected to the mounting protrusion 33.1.

[0047] The control arm 40 comprises a first and a second telescoping arm 41, 42. The first telescoping arm 41 thereby forms an outer telescoping arm in which the second telescoping arm 42 is linearly displaceably supported as an inner telescoping arm. By sliding the second telescoping arm 42 correspondingly relative to the first telescoping arm 41, the length of the control arm 40 can be changed. The second telescoping arm 42 comprises a mounting segment 43 on the end thereof facing away from the first telescoping arm 41. The mounting segment 43 is curved in shape. At the end thereof, the mounting segment 43 is pivotably connected to a flap bearing 50 by means of a pivot bearing 51. The flap bearing 50 is attached at the inner surface of the second partial flap 19 of the folding flap.

[0048] The folding flap is pivoted about the furniture hinge 21 for opening and closing the item of furniture 10. The second partial flap 19 is thereby guided by the central hinge 22 and the lifting device. The lifting device transmits a force acting in the opening direction from the flap holder 30 to the folding flap by means of the control arm 40 and the flap bearing 50.

[0049] When opening the folding flap, the second partial flap 19 is also pivoted about the pivot axis 33.4 of the flap holder 30 shown in FIG. 7. This leads to a folding motion of the two partial flaps 18, 19 about the central hinge 22, such that said flaps are oriented at an acute angle to each other and are supported by the lifting device in the upper region of the item of furniture 10.

[0050] In the closed state, the two partial flaps 18, 19 contact the furniture frame in a plane. The control arm 40 is then disposed in the interior of the item of furniture 10 and runs to the side of the folding flap. The curved shape of the mounting segment 43 guides the control arm 40 to the pivot bearing 51 on the flap bearing 50 protruding into the furniture frame. The closed state defines the required length of the control arm 40. If the control arm 40 is too long or too short, the folding flap cannot be closed so as to completely contact the furniture frame. When using flap levers not adjustable in length as a connection between the flap holder 30 and the flap bearing 50, flap levers of a suitable length must be provided for items of furniture of different sizes. This is logistically complex and leads to malfunctions, for example if an incorrect flap lever is used. A control arm 40 adjustable in length can be used for adapting to the particular installation conditions.

[0051] FIG. 2 shows a perspective side view of the control arm 40. The second telescoping arm 42 comprises a rectangular cross section. The first telescoping arm 41 is implemented in the shape of a tube. Said arm has a rectangular inner cross section. A receptacle for the second telescoping arm 42 is thus implemented along the length thereof. The second telescoping arm 42 is inserted partially into the first telescoping arm 41 here. By pushing the second telescoping arm 42 into the first telescoping arm 41, or pulling the second telescoping arm 42 out of the first telescoping arm 41, the length of the control arm 40 can be adjusted. The two telescoping arms 41, 42 can be fixed to each other by means of a fixing screw 65. A grooved 42.1 is machined into the second telescoping arm 42. The groove 42.1 runs along the length of the control arm 40. Said groove is open toward the side of the fixing screw 65. At the end thereof, the second telescoping arm 42 implements the curved mounting segment 43. The mounting segment 43 is penetrated by an axial hole 43.1 at the end thereof. The axial hole 43.1 is aligned transverse to the length of the control arm 40. Said hole serves as part of the pivot bearing 51 of the articulated connection of the control arm 40 to the flap bearing 50 shown in FIG. 1.

[0052] FIG. 3 shows a plan view of a segment of the control arm 40. The second telescoping arm 42 is inserted partially into the first telescoping arm 41. The view allows seeing into the groove 42.1 of the second telescoping arm 42. The groove 42.1 is laterally bounded by groove side walls 42.3 spaced apart from each other. Opposite the opening of the groove 42.1, said groove is closed off by a groove floor 42.2. Detent receptacles 42.4 are formed in the groove floor 42.2 along the length of the second telescoping arm 42. The detent receptacles 42.4 are implemented as recesses in the groove floor 42.2. Here said grooves have a contour tilted relative to the groove floor 42.2 at the edge and running flat at the floor thereof. It is also conceivable, however, to provide other contours of the detent receptacles 42.4, for example in the form of a spherical segment. The detent receptacles 42.4 are each spaced apart from each other at a constant detent spacing 42.5. Each detent receptacle 42.4 is associated with a length indication of the control arm 40 in the form of a scale 42.6. The fixing screw 65 is guided through a locking hole 41.1 into the interior of the first telescoping arm 41. In the plan view, a screw head 65.2 having a tool receptacle 65.3 of the fixing screw 65 can be seen. The screw head 65.2 is disposed within the locking hole 41.1.

[0053] The mounting segment 43 has a tapering cross section relative to the segment of the second telescoping arm 42 receiving the groove 42.1.

[0054] FIG. 4 shows an exploded view of a segment of the control arm 40. A T-nut 60 is associated with the groove 42.1. The T-nut 60 is sized so as to be inserted and guided in the groove 42.1. A base part 60.1 of the T-nut 60 is rounded on the end thereof. The groove 42.1 is correspondingly rounded at the end thereof. The T-nut 60 can thus be displaced fully to the end of the groove 42.1. The T-nut 60 is penetrated by a pin guide 61 aligned transverse to the length of the groove 42.1. The pin guide 61 is a through hole open toward the groove 42.1 and on the opposite side. As can be seen particularly in FIG. 5, the pin guide 61 is expanded facing toward the groove 42.1 as a spring support 61.1. A spring 63 is associated with the spring support 61.1. The spring 63 is implemented as a compression spring. Said spring preloads a detent pin 62. The detent pin 62 comprises a cylindrical shaft 62.1. A pin head 62.2 is formed on the end of the shaft 62.1. The pin head 62.2 is oriented toward the groove 42.1, while the shaft 62.1 faces the spring 63 and the pin guide 61. The pin head 62.2 is implemented facing the groove 42.1 corresponding to the contour of the detent receptacles 42.4 shown in FIG. 3. The cross section of the shaft 62.1 of the detent pin 62 is adapted to the pin guide 61 of the T-nut 60. The shaft 62.1 can thus be inserted into the pin guide 61 and guided therein.

[0055] The T-nut 60 is further penetrated by a screw receptacle 64. The screw receptacle 64 is aligned corresponding to the pin guide 61. Said screw receptacle thus faces toward the groove 42.1. Facing away from the groove 42.1, the screw receptacle 64 is expanded into a screw head receptacle 64.1. The pin guide 61 and the screw receptacle 64 are spaced apart from each other corresponding to the detent spacing 42.5 (see FIG. 3) between the detent receptacles 42.4.

[0056] The fixing screw 65 is associated with the locking hole 41.1. The fixing screw 65 comprises a threaded segment 65.1 on which the screw head 65.2 having the tool receptacle 65.3 is formed. The threaded segment 65.1 is adapted to the screw receptacle 64 of the T-nut 60. The fixing screw 65 can be threaded through the locking hole 41.1 into the screw receptacle 64 of the T-nut 60, when said T-nut 60 is guided in the groove to the locking hole 41.1, such that the locking hole 41.1 is aligned with the screw receptacle 64.

[0057] FIG. 5 shows a partial section side view of the control arm 60. The section view relates to the transition region from the first to the second telescoping arm 41, 42. The second telescoping arm 42 is inserted as far as possible into the first telescoping arm 41 in the representation shown. The control arm 40 thus has the least possible length. The T-nut 60 is disposed in the groove 42.1 of the second telescoping arm 42. The T-nut 60 is thereby aligned relative to the first telescoping arm 41 such that the screw receptacle 64 is aligned with the locking hole 41.1. The fixing screw 65 is threaded into the screw receptacle 64. The screw head 65.2 of the fixing screw 65 is thereby partially received in the screw head receptacle 64.1 of the T-nut 60. The outer region of the screw head 65.2 protrudes into the locking hole 41.1 of the outer telescoping arm 41. The T-nut 60 is thereby retained at the first telescoping arm 41. The spring 63 is inserted into the spring support 61.1. The shaft 62.1 of the detent pin 62 is guided by the spring 63 to the pin guide 61 and radially retained therein. The spring 63 is under load between the pin head 62.2 and the transition segment between the spring support 61.1 and the pin guide 61 tapered for this purpose. The spring presses the pin head 62.2 of the detent pin 62 in the direction toward the groove floor 42.2 of the groove 42.1. The groove 62.1 is closed off by the first telescoping arm 41 opposite the groove floor 42.2 in the region of the T-nut 60. The spring force of the spring 63 transferred to the T-nut 60 is thus supported by the first telescoping arm 41.

[0058] In the position shown for the two telescoping arms 41, 42 relative to each other, the detent pin 62 is disposed opposite a detent receptacle 42.4 in the groove floor 42.2 of the groove 42.1. The pin head 42.2 is thereby pressed into the detent receptacle 42.4 by the acting spring force. The pin head 42.2 and the detent receptacle 42.4 thus form a detent connection due to the acting spring force. Said detent connection fixes the T-nut 60 relative to the second telescoping arm 42. At the same time, the T-nut 60 is connected to the first telescoping arm 41 by the fixing screw 65. An effective detent connection is thus produced between the two telescoping arms 41, 42. A sufficiently great force acting along the length of the control arm 40 between the two telescoping arms 41, 42 overcomes the spring force acting on the detent pin 62. The telescoping arms 41, 42 can thus be displaced linearly relative to each other and the length of the control arm 40 can thus be adjusted. When the next detent receptacle 42.4 is reached, the pin head 62.2 of the detent pin 62 is again pressed into said receptacle by the spring force. The change in length of the control arm 40 can thus be performed at a fixed raster defined by the detent spacing 42.5 between the detent receptacles 42.4. When the control arm 40 has the desired length, the T-nut 60 can be locked relative to the second telescoping arm 42 by the fixing screw 65. Because the same spacing is selected between the pin guide 61 and the screw receptacle 64 as the detent spacing 42.5 between the detent receptacles 42.4, when the detent pin 62 is engaged in a detent receptacle 42.4, the fixing screw 65 is disposed precisely opposite a further detent receptacle 42.4. The fixing screw 65 can then be threaded into the screw receptacle 64 of the T-nut 60 far enough that the end of the shaft thereof 62.1 protrudes out of the screw receptacle 64 and into the detent receptacle 42.4. In the present setting of the fixing screw 65, the T-nut 60 is thus fixed relative to the second telescoping arm 42. The screw head 65.2 of the fixing screw 65 is designed so as to at least partially protrude into the locking hole 41.1 of the first telescoping arm 41, even in the threaded-in position of the fixing screw 65. The T-nut 60 thereby remains fixed relative to the first telescoping arm 41 as well. The threaded-in fixing screw 65 thus locks the linear displacement of both telescoping arms 41, 42 relative to each other.

[0059] FIG. 6 shows a side section view of a segment of the control arm 40. The design and function of the telescoping arms 41, 42 and the fixing screw 65 corresponds to the description for FIGS. 1 through 5, to which reference is hereby made. The T-nut 60 further comprises a screw receptacle 64 into which the fixing screw 65 is threaded.

[0060] The function of the detent pin 62 is taken on by a detent protrusion 66 having a detent head 66.1. The detent protrusion 66 is implemented as a tab formed on the base part 60.1 of the T-nut 60. Said tab is aligned in the direction of the length of the control arm 40. The detent protrusion 66 thus runs spaced apart from the groove floor 42.2. The detent head 66.1 is formed on the free end of the detent protrusion 66.

[0061] Said head is aligned in the direction toward the groove floor 42.2. The shape of the detent head 66.1 is adapted to the contour of the detent receptacles 42.4. The detent protrusion 66 is elastic in design. The detent head 66.1 is thus pressed against the groove floor 42.2 by the detent protrusion 66. When the detent head 66.1 is disposed opposite a detent receptacle 42.4, the head is pressed into the detent receptacle 42.4 by the spring-loaded effect of the detent protrusion 66. A detent connection is thereby produced between the T-nut 60 and the detent receptacle 42.4 and thus the second telescoping arm 42. The partially threaded-in fixing screw 65 does not engage in one of the detent receptacles 42.4 and connects the T-nut 60 to the first telescoping arm 41 as described for FIG. 5. An effective detent connection is thus implemented between the two telescoping arms 41, 42. The detent head 66.1 is spaced apart from the fixing screw 65 corresponding to the detent spacing 42.5 between the detent receptacles 42.4. When the detent head 66.1 is engaged in a detent receptacle 42.4, the fixing screw 65 is thus disposed opposite a detent receptacle 42.4. By threading in the fixing screw 65, said screw can engage with the detent receptacles 42.4. The T-nut 60, as previously described for FIG. 5, is thus fixed to the second telescoping arm 42. A linear displacement of the two telescoping arms 41, 42 relative to each other is thus no longer possible. The length of the control arm 40 is thus fixed. It is also conceivable to guide the fixing screw 65 through the T-nut 60 toward the detent head 66.1. A fixing screw 65 thus disposed can then be threaded in to bear against the side of the detent protrusion facing away from the detent receptacle 42.4 and lock the same. Releasing of the detent connection is thereby prevented and the telescoping arms 41, 42 are mutually fixed. By threading out a fixing screw 65 thus disposed, the detent protrusion 66 is again released and the detent head 66.1 can slip out of the detent receptacle 42.4 when corresponding force is applied.

[0062] If the detent connection is implemented by a detent protrusion 66 of the T-nut 60, the detent protrusion 66 formed thereon is preferably made of an elastic material, particularly of a metal or a plastic.

[0063] FIG. 7 shows a side section view of the item of furniture 10 shown in FIG. 1 having the folding flap joined by a hinge, the lifting device, and the control arm 40. The section is thereby placed through the control arm 40.

[0064] The control arm 40 is implemented according to the description for FIGS. 1 through 6, wherein a T-nut 60 having a detent pin 62 is used, as shown in FIGS. 4 and 5.

[0065] The first telescoping arm 41 comprises an attachment region 41.3 at the end thereof facing toward the item of furniture 10, by means of which said arm is placed on the mounting protrusion 33.1 of the lever 33 of the flap holder 30. The mounting protrusion 33.1 preferably comprises a stop, not shown, against which the fully placed first telescoping arm 41 bears. Such a stop ensures the correct positioning of the control arm 40 relative to the mounting protrusion 33.1. In said position, a threaded hole made in the mounting protrusion 33.1 is aligned with a fixing hole 41.4 on the first telescoping arm 41. The threaded hole 33.2 is expanded into a head receptacle 33.3 toward the fixing hole 41.4. A threaded segment 35.1 of the fixing screw 35 is threaded into the threaded hole 33.2 such that the screw head thereof is disposed at least partially in the head receptacle 33.3. The screw head of the fixing screw 35 comprises a stop ring 35.2 transitioning into a fixing segment 35.3 opposite the threaded segment 35.1. The fixing segment 35.3 comprises a reduced diameter in comparison with the stop ring 35.2. A tool engagement 35.4 is formed in the fixing segment 35.3 and in the region of the stop ring 35.2. The diameter of the fixing segment 35.3 is slightly smaller than the diameter of the fixing hole 41.4 on the telescoping arm 41, while the diameter of the stop ring 35.2 is greater than the diameter of the fixing hole 41.4. For attaching the control arm to the mounting protrusion 33.1, the fixing screw 35 is first threaded into the threaded hole 33.2 far enough that the head of the fixing screw 35 is fully received by the head receptacle 33.3 formed in the mounting protrusion 33.1. The head of the fixing screw thus no longer protrudes above the mounting protrusion 33.1 and the first telescoping arm 41 can be placed onto the mounting protrusion 33.1, preferably against stop. In the present installed position, the fixing hole 41.4 is aligned with the fixing segment 35.3 of the fixing screw 35. As shown in more detail in FIG. 8, a tool 70 can now be guided through the fixing hole 41.4 to the tool engagement 35.4 of the fixing screw 35 and said screw can be partially threaded out from the threaded hole 33.2 until the stop ring 35.2 bears all around against the fixing hole 41.4 on the first telescoping arm 41, and the fixing segment 35.3 of the fixing screw 35 engages with the locking hole 41.1. The control arm 40 is thus fixed to the mounting protrusion 33.1 of the lever 33 and can no longer be pulled off.

[0066] An actuating space 41.2 is implemented between the mounting protrusion 33.1 and the end of the second control arm 42 in the first telescoping arm 41 and increases or decreases as the telescoping arms 41, 42 are displaced relative to each other. The actuating space 41.2 is designed such that when the second telescoping arm 42 is fully inserted, said arm does not bear against the mounting protrusion 33.1

[0067] The lever 33 is pivotably supported on the pivot axis 33.4 of the flap holder 30 by means of an attaching segment 33.5. A coupling piece 34 is hinged to the lever 33, by means of which the force of one or more springs, not shown, provided in the flap holder 30 is transferred to the lever 33 and thus to the control arm 40. Said spring force supports the opening and closing motion of the folding flap, as previously described, and holds the same in partially opened positions.

[0068] The control arm 40 is connected opposite the flap holder 30 to the flap bearing 50 disposed on the folding flap. The flap bearing 50 comprises an installation support 53 screwed to the inner side of the second partial flap 19 by means of installation screws 54. A bearing part 52 is linearly displaceably connected to the installation support 53. The displacement path thereby runs along the plane of the second partial flap 19 and the project of the control arm 40 onto the second partial flap 19. The correct position of the bearing part 52 and the pivot bearing 51 connected thereto can be adjusted and locked by means of an adjusting screw.

[0069] When installing the lifting device, the length of the control arm 40 is first adapted to the size of the present item of furniture 10 and the hinged folding flap. The length can thereby be read from the scale 42.6 shown in FIG. 3. The length is adjusted according to the detent specifications by the detent connection between the two telescoping arms 41, 42. The detent spacing 42.5 between the detent receptacles 42.4 is at a whole-number ratio to the hole spacing 17 between the front wall holes 16.1. The hole spacing 17 of the wall holes 16.1, 16.2 is thereby largely standardized and is typically 32 mm. The detent spacing 42.5 of the detent connection of the control arm 40 is defined here as 8 mm. When the item of furniture 10 is closed, the telescoping arm 41, 42 is aligned according to the series of front wall holes 16.1. The whole-number ratio of the detent spacing 42.5 between the detent receptacles 42.4 to the hole spacing 17 of the wall holes means that the length of the control arm 40 can be set to the required length despite the rastered, non-continuous adjustment of the length. The required length, as previously described, is thereby defined by the installed position of the flap holder 30 and the flap bearing 50 when the item of furniture 10 is closed. When the length of the control arm 40 is adjusted correctly, the two telescoping arms 41, 42 are fixed to each other by the fixing screw 65. Small deviations of the length of the control arm 40 from the precise required length can be compensated for by corresponding linear displacement of the location of the pivot bearing 51. This is done by correspondingly displacing the bearing part 52 relative to the installation support 53. The correct length of the control arm 40 and the position of the pivot bearing 51 is achieved when the folding flap makes full contact with the furniture frame when the item of furniture 10 is closed, and the two partial flap 18, 19 are aligned to each other in one plane. The displacement range of the flap bearing 50 advantageously corresponds to at least the length of one detent spacing 42.5. Any deviation of the length of the control arm 40 from the required length of less than one detent spacing 42.5 can thereby be compensated for by correspondingly positioning the pivot bearing 51. Greater deviations can be compensated for by adapting the length of the control arm.

[0070] Simple adjustment of the length of the control arm 40 can be done in that the lifting device, to which the folding flap has previously been mounted and aligned, is first installed on the item of furniture 10. The folding flap is then closed while the linear displacement of the flap bearing 50 is locked and the fixing screw 65 of the control arm 40 is released. The closed state of the item of furniture 10 defines the precise required length of the control arm 40. When the folding flap is closed, the telescoping arms 41, 42 thus displace such that the control arm 40 takes on the required length according to the detent spacing 42.5. The retaining force of the detent connection between the telescoping arms 41, 42 is selected such that when the folding flap is then opened, the length of the control arm 40 does not change. The length of the control arm 40 can now be easily fixed while the folding flap is open and thus the fixing screw 65 is accessible. Fine adjustment of the closing position of the folding flap is then made by adjusting the flap bearing 50 accordingly.

[0071] FIG. 8 shows a side section view of a segment of the control arm 40. As previously described, the fixing screw 35 can be threaded out by engaging a suitable tool so that the fixing segment 35.3 thereof is guided in the fixing hole 41.4, whereby the first telescoping arm 41 is fixed relative to the mounting protrusion 33.1.