U.S. patent number 3,916,591 [Application Number 05/450,810] was granted by the patent office on 1975-11-04 for spindle staircase.
This patent grant is currently assigned to Gebr. Agterhof N.V., Gieterij Doesburg B.V.. Invention is credited to Henk Agterhof, Johannes Antony DEWaal.
United States Patent |
3,916,591 |
Agterhof , et al. |
November 4, 1975 |
Spindle staircase
Abstract
Conventionally a spindle staircase is mounted in the building in
the course of construction so that fine, for example, hard-wood
steps may be damaged or be at least soiled with building material
on account of rough treatment. Cleaning of the steps requires much
labour and time. If during the building operations steps are
damaged, they have to be replaced by new ones, resulting in high
costs. These problems are avoided by first fastening provisional
step units formed each by a working step and a step support secured
thereto in a detachable manner to the spindle and by replacing
these provisional step units afterwards by new ones.
Inventors: |
Agterhof; Henk (Doetinchem,
NL), DEWaal; Johannes Antony (Doetinchem,
NL) |
Assignee: |
Gieterij Doesburg B.V.
(Doesburg, NL)
Gebr. Agterhof N.V. (Doetichem, NL)
|
Family
ID: |
19819072 |
Appl.
No.: |
05/450,810 |
Filed: |
March 13, 1974 |
Foreign Application Priority Data
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Jun 13, 1973 [NL] |
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7308231 |
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Current U.S.
Class: |
52/187;
52/73 |
Current CPC
Class: |
E04F
11/032 (20130101) |
Current International
Class: |
E04F
11/02 (20060101); E04F 11/032 (20060101); E04F
011/02 () |
Field of
Search: |
;52/187,182 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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1,565,588 |
|
Mar 1969 |
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FR |
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1,047,846 |
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Nov 1966 |
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GB |
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1,533,333 |
|
Jun 1968 |
|
FR |
|
955,861 |
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Apr 1964 |
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UK |
|
Primary Examiner: Sutherland; Henry C.
Attorney, Agent or Firm: Hill, Gross, Simpson, Van Santen,
Steadman, Chiara & Simpson
Claims
What we claim is:
1. A spindle staircase comprising:
a. a spindle having a plurality of spindle sections;
b. a step holder attached to at least some of said spindle
sections, said step holder having an elongated, three-sided gutter
and tongue-like cam;
c. a detachable step support having a bar and integral bridge
piece, said bar being received in said step holder gutter and
fitting with said cam;
d. means for locking said bar in said gutter; and
e. a step connected to said step support by screws hidden from view
at the top side of the step;
whereby said step support with connected step is easily removable
by releasing the means for locking, and said step may be
conveniently replaced by mounting a new step to said step support
at a convenient work area.
2. A spindle staircase as claimed in claim 1 in which said step
holder and attached spindle are an integral casting.
3. A spindle staircase as claimed in claim 1 in which said step
holder is detachably connected to said spindle sections by recesses
on said step holder and matching pins on said spindle section, said
recesses and pins being locked together by screws.
4. A spindle staircase comprising:
a. a spindle having a plurality of spindle sections, at least some
of which have a first channel section connection element as an
integral part thereof;
b. a step holder having a gutter and a second channel section
connection element, said first and second channel section elements
mating and being locked together by a single locking screw to form
a detachable connection between said step holder and said spindle
sections with first channel section elements;
c. a step support having a bar and a transverse metal strip at one
end thereof said bar being received in said step holder gutter;
and
d. a step connected to both said metal strip of the step support
and said step holder by screws hidden from view at the top side of
said step;
whereby said step holder with attached step and step support is
easily detachable by removing said locking screw, and said step may
be easily replaced by mounting a new step to said step support and
step holder at a convenient work area.
5. A spindle staircase comprising:
a. a spindle having a plurality of spindle sections;
b. a step holder attached to at least some of said spindle
sections, said step holder having an elongated, three-sided
gutter;
c. a detachable step support having a bar and integral bridge
piece, said bar being received in said step holder gutter;
d. means for locking said bar in said gutter; and
e. a step connected to said step support by screws hidden from view
at the top side of the step;
whereby said step support with connected step is easily removable
by releasing the means for locking, and said step may be
conveniently replaced by mounting a new step to said step support
at a convenient work area.
Description
The invention relates to a method of mounting a spindle staircase
in a building, said staircase comprising a spindle and a plurality
of steps, each of which is secured to the spindle by means of a
step support.
In the prior art method the spindle staircase is mounted in the
building in the course of construction so that fine, for example,
hard-wood steps may be damaged or be at least soiled with building
material on account of rough treatment. Cleaning of the steps
requires much labour and time. If during the building operations
steps are damaged, they have to be replaced by new ones. From the
aesthetical point of view it cannot be allowed to insert screws
into the steps from the top side. For this reason screws are
inserted into the steps from below in order to fasten them to the
step supports, which is a troublesome operation: it is not possible
to use strong screws which require a heavy pressure for screwing
into and out of the wood.
The invention provides a method of the kind set forth, which
dissolves the aforesaid problems by first fastening provisional
step units formed each by a working step and a step support secured
thereto in a detachable manner to the spindle and by replacing
these provisional step units afterwards by new ones. Because the
step is screwed to the associated step support when the step
support is not yet fastened to the spindle, screwing may be carried
out in an upside down position of the step unit so that rugged
screws can then be readily inserted by heavy pressure into a
hard-wood step.
The invention provides furthermore a set of provisional step units
each consisting of a working step and a step support secured
thereto, characterised by securing means for securing said step
unit detachably and provisionally to a spindle of a spindle
staircase. This set can be repeatedly employed for mounting spindle
stairs of the same type.
In addition the invention provides a spindle staircase at least
comprising a spindle built up from spindle sections and a plurality
of steps, each of which is fastened by means of a step support in a
detachable manner to a section of the spindle, said staircase being
particularly suitable in carrying out the method according to the
invention, because the step support comprises a step holder secured
to a spindle section and manufactured like said spindle section by
casting of spray-casting. Casting or spray-casting enables accurate
manufacture of spindle section and step holder accurately
registering with each other. The spindle section and the step
holder may be manufactured as a single casting, in which case the
step support is preferably formed by a profiled bar secured to the
step and adapted to be detachably fastened to the step holder.
The spindle sections and/or the step holders are, for example, made
of aluminum or nodular cast iron, but preferably of malleable cast
iron (temper iron). The detachable connection between the step
holder and the spindle section is particularly simple and rigid,
when one of the two connecting elements has at least one pin and
the other connecting element has at least one recess matching said
pin.
Preferably one connecting element has two conical pins whereas the
other connecting element has two matching conical recesses, whilst
the step holder is connected with the spindle section not only by
means of said pin-recess connection but also by a safety screw.
The staircase comprising at least a spindle built up from spindle
sections, a plurality of steps and a plurality of profiled bars
each secured to a step and each engaging in a detachable manner a
gutter-shaped step support of a spindle sections is improved
according to a further development of the invention in that each
profiled bar extends as fas as into the spindle. In this case the
gutter-shaped step support may be shorter so that material is
saved, whilst casting of such a spindle section is facilitated.
Moreover, this spindle staircase has a more beautiful appearance,
whilst adequate rigidity is maintained.
In order to further simplify the shape of the spindle sections each
profiled bar is in abutment with the lower rim of the superjacent
spindle section.
The exchange of steps can be very readily carried out, if at least
one transverse strip welded to each profiled bar is fastened by
means of at least one bolt to the guttershaped step support of a
spindle section.
A rattle-free, simply mounted spindle staircase is obtained when
each profiled bar bears in at least two internal ridges of the
gutter-shaped step support made to measure after casting.
The aforesaid and further features of the invention will be
explained more fully in the following description of an embodiment
of the spindle staircase in accordance with the invention with
reference to a drawing.
In the drawing:
FIG. 1 is a perspective view of a preferred embodiment of spindle
stairs in accordance with the invention,
FIG. 2 is an enlarged elevation partly broken away of the lower end
of the spindle stairs shown in FIG. 1,
FIG. 3 is a sectional view taken on the line III--III in FIG.
2,
FIG. 4 is a sectional view taken on the line IV--IV in FIG. 2,
FIG. 5 is an enlarged perspective view of the dismounted parts of a
step of the spindle stairs shown in FIG. 1,
FIG. 6 is an enlarged, perspective view of a detail of the spindle
of the spindle stairs shown in FIG. 1 with mounting tools,
FIGS. 7 and 8 show tools for orientating the cast spindle sections
and step holders,
FIGS. 9 and 10 show each a detail like that of FIG. 2 for two
variants of the spindle stairs in accordance with the
invention,
FIG. 11 is a plan view, partly broken away, of the detail of FIG.
10,
FIG. 12 is a vertical sectional view of part of a spindle and the
two steps of a further developed spindle staircase embodying the
invention,
FIG. 13 is an enlarged perspective view of the dismounted parts
associated with a step of the spindle staircase shown in FIG.
12,
FIG. 14 is an enlarged sectional view taken on the line XIV--XIV in
FIG. 12,
FIG. 15 is an enlarged sectional view taken on the line XV--XV in
FIG. 12,
FIG. 16 is a plan view of a casting for a spindle section still to
be finished of the spindle staircase of FIG. 12,
FIG. 17 is a sectional view taken on the line XVII--XVII in FIG.
16, and
FIG. 18 is a sectional view taken on the line XVIII--XVIII in FIG.
16.
The spindle staircase 1 of FIG. 1 comprises a spindle 2 built up
from alternately piled spindle sections 3 and 4 and a plurality of
steps 5, each detachably fastened by means of a step holder 6 to a
connecting element 7 rigidly secured to the former and to a
connecting element 8 rigidly secured to the spindle section 3. Each
step holder 6 and each spindle section 3 together with an integral
connecting element 7 and 8 respectively are manufactured by casting
or spray-casting.
Each spindle section 3 comprises a casting having a cylindrical
sheath 9 having annularly recessed rims 11, which engage the
adjacent rims 12 of the spindle sections 4 formed in the shape of
spacer sleeves.
Each spindle section 3 formed by a single casting comprises
furthermore a transverse wall 13, a console 14 with two conical
pins 15 at right angles thereto, the diameter of which decreases
towards the free top end. The console 14 and the two pins 15 form
together the connecting element 8 integral with the spindle section
3. The other connecting element 7 integral with the cast step
holder 6 has two conical recesses 16 matching the pins 15. The
connecting elements 7 and 8 are interconnected not only by said
pins 15 and recesses 16 but also by means of a safety screw 17,
which is countersunk in the console 14 and engages a tapped hole 19
of the connecting element 7.
The direction of the step 5 with respect to the spindle section 3
is completely determined by the accurate match of the pins 15 and
the recesses 16. On the outer side the connecting elements 7 and 8
fit one into the other as is shown in the drawing -- be it with a
slight amount of clearance 20 -- so that a smooth appearance of the
transition from the spindle section 3 to the step holder 6 is
obtained. The step holder 6 has a channel-section profile tapering
towards its free end and having stiffening ridges 21 forming a
elongated, three-sided gutter 25 for accommodating a profiled bar
22. During the casting operation the step holder 6 is provided with
ears 23 having holes 24 and with a tongue-like cam 26 having a
downwardly extending extension 27. The extension 27 is engaged in
an opening 28 of the profiled bar 22 formed by a square-section
tubing.
The end 29 of the step 5 remote from the spindle 2 is held via the
profiled bar 22 on the step holder 6 and is secured to the profiled
bar 22 by means of a bridge piece 30 made by casting, having holes
31 for passing the bridge piece 30 and screws 32 of the step 5 and
having a bearing 33 matching the profiled bar 22 and engaging the
latter.
In the spindle staircase 1 shown in FIGS. 1 to 9 and in FIGS. 11
and 12 the profiled bar 22 and a step holder 6 constitutes together
a step support. Such a step support together with a step 5
constitutes a step unit 37.
A step unit 37 is assembled as follows. A fine step 5, for example,
a hardwood board or a slab of natural stone, metal or other
material is screwed by its end 29 to the bridge piece 30. A
profiled bar 22 is put into the gutter 25 of the step holder 6, the
opening 28 engaging the extension 27 of the cam 26. The profiled
bar 22 is arranged around the bearing 33 and the step 5 is secured
to the step holder 6 by means of screws 34 and 35 passed through
holes 24 and extending through holes 36 registering with the
recesses 16.
The spindle 2 is assembled as follows. A castiron foot plate 38 is
put in a horizontal position and secured by bolts 39 to the floor
40. The foot plate has a collar 41, around which grips a spindle
section 42 formed by a short tubing and a central tapped sleeve 43
receiving a bolt 44, the head 45 of which engages the transverse
edge 13 of the spindle section 3, which is previously put down on
the spindle section 42 and is orientated by its connecting element
8 in the required direction. Then a long spindle section 4 is
arranged on the spindle section 3 and a spindle section 3 is put
down on the former. The alignment of every further spindle section
3 is performed by means of tools 46 (FIG. 6) formed by a horizontal
foot 47 having two conical recesses 48 fitting to two pins 15 and a
vertical bar 49 fastened to the foot and fitting in a hole 18 and
being displaced through an angle a with respect to the centre b
between the recesses 48. The angle a is equal to the required tread
angle of the steps 5 of the spindle staircase 1. The foot 47 is
fitted by its recesses 48 to the pins 15 of the spindle section 3
previously fastened and the next-following spindle section 3 is
slipped by the hole 18 onto the bar 48. After tightening a bolt 50
in the head 45 of a lower bolt 44 the spindle section 3 is rigdly
secured to the subjacent portion of the spindle 2 with the required
accurate angular displacement a. In this way the spindle is built
up stepwise and preferably crowned with a spindle section 51 in the
form of a pole, which serves as a support for banisters (not
shown). The upper spindle section 52 is secured to a ceiling 56 by
means of a supporting plate 53 and bolts 54 and 55.
In the method according to the invention first provisional step
units 37 having ordinary steps, for example, of deal are secured to
the spindle 2 for use during the building operations by slipping
the step holders 6 thereof onto the pins 15 and by screwing in the
safety screw 17. After the completion of the building and, as the
case may be, after the installation of furniture said provisional
step units 37 having the function of working steps are replaced by
new step units 37, the steps 5 of which are made of fine
hard-wood.
The spindle sections 3 and 52, the step holders 6 and the bridge
pieces 30 are preferably made of malleable cast iron (tempered
iron). They are cast in a conventional manner in sand moulds and
annealed by a tempering annealing process and subsequently
aligned.
FIGS. 7 and 8 show each a stationary die table 58, to which a lower
die 59, 60 is secured for receiving a step holder 6 and a spindle
section 4 respectively and an aligning die 61, 62 pushed downwards
for aligning the step holder 6 and the spindle section 4
respectively.
With spindle stairs 1 for various storeys the same spindle sections
4 are employed and the lengths of the spindle sections 3 for
different spindle stairs 1 are adapted to the relevant heights of
the storeys.
The spindle 2 can be readily mounted in the factory together with
the foot plate 38 and be transported as a whole to the building
site, the space occupied in transport being small. The step units
37 can be suspended in situ to the erected spindle 2.
In the variant shown in FIG. 9 one connecting element 8 having two
pins 15 is cast integrally with the step holder 6, whereas the
other connecting element 7 having recesses 16 matching the pins 15
is cast integrally with the spindle section 3. A safety screw 17
extends through a hole of the connecting element 7 and is screwed
into the connecting element 8.
In the variant shown in FIGS. 10 and 11 the step holder 6 and the
spindle section 3 form part of one casting 63 so that they can be
accurately aligned relatively to one another by means of dies as
described above. The detachable step unit 65 illustrated in FIGS.
10 and 11 comprises a step 5 and a profiled bar 22 forming a step
support and secured to said step by means of the above-mentioned
bridge piece 30. The profiled bar 22 is furthermore fastened to the
step 5 by means of wood-screws 64. The step unit 65 can be readily
secured to the step holder 6 by slipping the profiled bar 22 into
the gutter 25 of the step holder beneath the cam 26 and by
inserting finally a single screw or pin 66 through holes of the
profiled bar 22 and of the step holder 6.
The bridge piece 30 has an ear 67 projecting from the step 5 and
having fastened to it a baluster 68 of a handrail (not shown) by
means of a screw member 69 fastened in the baluster 68 and of a cap
nut 70.
FIG. 12 shows that a channel-section connecting element 8 may have
two flanges 71 on each spindle section 3, said flanges being
connected with the flanges 72 of the channel-section connecting
element 7 of the step holder 6 by means of a tapped sleeve 75 to be
passed through the flanges 71 and 72 and of a shoulder screw 79 to
be screwed into the tapped sleeve 75. The connecting element 7 of
the step holder 6 bears on a stop rim 73 as well as below on a stop
rim 80 of the spindle section 3. A hard-wood step 5 is preferably
fastened to the step holder 6 and the bridge piece 30 respectively
with the interposition of a rubber layer 81 and rubber rings 76 to
reduce the transfer of body sound as is shown in FIG. 12 whilst
rubber washers 79 are arranged around the screws 64 and 32.
Within the scope of the invention various modifications of the
embodiments described and shown are possible. For example, each
spindle section 3 may have two diametrically opposite connecting
elements 8 so that a twin staircase is obtained by fastening steps
of two helical runs to one and the same spindle.
The pins 15 of the connecting elements 8 and the matching recesses
of the connecting elements 7 may have a pyramidal shape rather than
a conical form, for example, they may have the shape of a truncated
cone of rectangular or dovetail-shaped section.
Whilst for mounting the spindle 2 in the building it is preferred
for the spindle to have a series of inter-screwed bolts 44, it is
possible in prefabrication to use a bolt covering the whole length
of the spindle, the spindle sections 3 being then arranged in the
prescribed positions by means of a jig covering the length of the
spindle 2.
The spindle staircase 1 shown in FIGS. 12-16 comprises a spindle 2
built up from alternately stacked spindle sections 3 and 4 and a
plurality of steps 5. Each step 5, which may be made of wood, is
fastened by bolt screws 32 and has two transverse strips 82 and 83
welded to a profiled bar 22 having a squaresection hollow profile.
The step 5 has recesses 84 and 85 on the bottom side for receiving
the transverse strips 82 and 83. The step 5 together with the
profiled bar 22 constitutes an exchangeable step unit 65, which is
detachably fastened in a gutter-shaped step support 16, which is
united with the spindle section 3 in a single casting 63. The
casting has at the free end and at the centre of the step support 6
internal ridges 86 and 87, which are accurately planed or milled to
measure subsequent to casting along the broken lines 88 for a
rattle-free accomodation of a profiled bar 22.
The profiled bar 22 extends as far as into the spindle 2 and butts
against the lower rim 89 of the superjacent spindle section 4.
The profiled bar 22 guided in the step support 6 is secured to the
step support 6 by means of hollow screws 90 extending across
external ears 91 of the step support 6 into tapped holes 92 of the
transverse strip 83.
* * * * *