[0001] The present invention relates to a workbench including: a first support member pivotally
coupled to a second support member and wherein one of the first and second support
members is formed with detent-engaging means: detent means mounted on the other of
the first and second support members and co-operable with the detent-engaging means
thereby to selectively permit or prevent relative pivotal movement between the first
and second support members.
[0002] A device of the kind described above has been manufactured by the applicant for several
years now. Such a device comprises a main frame in the form of two pairs of legs,
each pair having mounted at its upper end a support member. The support members each
carry a pair of jaws which extend laterally across the support members. The support
members each have a threaded rod running therethrough which co-operates with correspondingly
threaded rings formed on the undersurface of each side of each of the pair of jaws.
In this way the user of the workbench can cause the pair of jaws to move together
or to separate by rotation of each threaded rod.
[0003] The support member for each of the jaws comprises a pair of metallic arms. One of
the support members has a hole punched through each of its metallic arms and the other
of the support members has two holes punched therethrough. These holes are arranged
so that when the first and second support members are moved in pivotal relationship
with one another, the holes are aligned both when the support members lie in the same
plane and when they lie in orthogonal planes. Furthermore, the support member which
has only one hole punched through its metallic arms, also carries a manually operable
drive pin which may be selectively pushed through this hole and which then also travels
through whichever one of two holes carried by each metallic arm of the other support
member with which it is aligned. This then serves to lock the support members in either
the same or orthogonal planes. The drive pin itself is caused to be either driven
through or retracted from these holes by way of a simple sprung cam mechanism. In
this manner, the user manually rotates the cam mechanism thereby causing the drive
pin to move.
[0004] A shortcoming of the above device is that the user needs to perform two separate
operations in order to alter the pivotal relationship between the two support members.
Firstly the drive pin needs to be withdrawn from its current hole, then the pivotal
relationship between the support members must be changed and finally the drive pin
must be driven through the other wholes for locking the arrangement in its new state.
Furthermore, it is advantageous to utilise an equally efficacious device which uses
components of cheaper cost than that of a cam-driven drive pin.
[0005] It is thus an object of the present invention to at least alleviate the above-mentioned
shortcomings by providing a workbench of the type described in the opening paragraph,
characterised in that the detent-engaging means comprises a channel formed in the
said one of the first and second support members, which channel defines first and
second regions, one of which first and second regions allows the detent means limited
movement therewithin and the other of the first and second regions restrains movement
of the detent means. By utilising a channel so formed, the need for a separate cam-driven
drive pin is obviated and hence a cheaper, more simple to operate device is achieved
than has hitherto been the case.
[0006] Preferably at least one of the first and second regions of the channel is substantially
arcuate, thereby to cause the detent to follow an arcuate path in sympathy with the
relative pivotal movement between the first and second support members. In this way
the detent is always within the detent-engaging means itself and so there is not need
for the operator of the workbench to have to align holes as is the case with the prior
art.
[0007] Alternatively, the other of the first and second regions of the channel defines a
stop for the detent means thereby to prevent relative pivotal movement between the
first and second support members. In this way, the support members can readily be
held in the desired relative orientation.
[0008] Preferably the stop is formed tangentially to the arcuate region of the channel.
Alternatively the stop may be substantially linear.
[0009] Additionally, there may be two of the other of the first and second regions, each
of the two of the other of the first and second regions flanking the first region.
This allows for the detent means to be held in, for example, two positions at 90°
separation.
[0010] In a preferred embodiment, the detent means is biased towards one of the first and
second regions. This allows for the detent to be automatically urged into its restrained
position within the detent-engaging means.
[0011] The detent means could be biased towards the other of the first and second regions.
Also the detent means could be biased by way of a spring member. The detent means
could comprise a manually operable bar.
[0012] The manually operable bar is preferably urged towards the or each stop by the spring
member.
[0013] Additionally or alternatively when the biasing of the bar coincides with the bar
being positioned within the channel directly over the or each stop, then the bar is
restrained within said the or each stop hence preventing relative pivotal movement
between the first and second support members.
[0014] The channel may be formed as a recess within the one of the first and second support
members. Alternatively, the channel may be formed as a hole within the one of the
first and second support members. Preferably the first and second support members
each support a pair of jaws of the workbench. The first and second support members
may each be formed on respective legs of the workbench. Preferably the first and second
support members each comprise a pair of supports.
[0015] The invention will now be described, by way of example only, and with reference to
the accompanying drawings, of which:
Figure 1 shows an exploded view of part of a workbench in accordance with the present
invention;
Figure 2 shows a perspective view from one side of the workbench of Figure 1;
Figure 3 shows a perspective view from below of the workbench shown in Figure 2;
Figure 4 shows a plan view from the underside of the workbench;
Figure 5 shows in detail the area of Figure 4 ringed "A";
Figure 6 shows a plan view from above of the workbench of the present invention;
Figure 7 shows a side view of part of a workbench with the support members lying in
the same plane;
Figure 8 shows a side view of part of a workbench with the support members of Figure
7 moving in pivotal relationship with each other;
Figure 9 shows a side view of part of a workbench with the support members lying in
orthogonal planes, and
Figure 10 shows an entire workbench in accordance with the present invention.
[0016] Referring firstly to Figures 1, 2 and 3 it can be seen that a part of a workbench
in accordance with the present invention comprises a first support member, in this
example a pair of bars (2), interconnected via a support bar (4). Each of the bars
(2) of the pair are adapted to receive therewithin a threaded vice screw (6). At one
end, the vice screw (6) is connected to an arm handle (8) so that a user of the workbench
may rotate the vice screw (6). The remainder of the length of the bar (2) carries
a thread and the rotation of the screw (6) via the handle (8) causes the thread to
move a spigot-bearing ring (10) coupled to the screw (6) along the length thereof
in known manner. The upper surface of the spigot-bearing ring (10) (the spigot itself)
couples with the underside of a block (12). The upper surface of block (12) itself
engages with a jaw (14). In this way, rotation of either of the arm handles (8) by
the user causes that side of the jaw (14) to move, as is known in the art. It will
also be seen that the two arm handles (8) as shown in the Figures can both be caused
to rotate by coupling them together via a transmission belt (15). This is simply for
ease of use as, if the jaw (14) is required to be moved backwards or forwards along
the length of the thread of the vice screws (6) without any lateral or angular disposition,
then this mechanism allows this to be achieved without the need for both arm handles
(8) to be rotated. Each bar (2) of the pair is pivotally coupled to a second support
member, in this example a pair of brackets (16). It can be seen from the example shown
in the figures that each bar (20) of the pair couples pivotally with a respective
bracket (16) of the pair of brackets (16).
[0017] Although not shown in the Figures for the sake of clarity, the brackets (16) themselves
support a further jaw in addition to jaw (14). This pivotal relationship between the
two pairs of support members - the bars (2) and the brackets (16) - thus allows these
two jaws to be in any relative orientation between lying in the same plane to lying
in orthogonal planes, as will be described below.
[0018] Referring now also to Figures 4, 5 and 6 it will be seen that the bars (2) of the
pair are adapted to hold a detent means, in this example a spring-biased arm (18).
The arm (18) is shaped so as to define two projecting ends (20) and a longitudinally
extending operable surface (22). In its rest state, the arm (18) is biased in the
direction of the arrow shown in Figure 5 by way of spring members, here coiled metal
springs (24).
[0019] The projecting ends (20) of the arm (18) co-operate with a detent-engaging means,
in this example shaped punched channel (26) shown in Figures 7, 8 and 9, formed in
each bracket (16) of the pair of brackets. The co-operation between the arm (18) and
the shaped channel (26) governs the relative pivotal movement between the bars (2)
and the brackets (16) and will be described in detail below.
[0020] Paying particular attention to the shape of the channel (26) and Figures 7, 8 and
9 for the present, it can be seen that it is formed in a generally arcuate shape being
flanked by two end portions. The arcuate portion (28) subtends a right-angle and is
so shaped to permit the projecting end (20) of arm (18) which co-operates with its
respective channel (26) to travel therewithin. It will be understood that travel of
the projecting end (20) within the arcuate portion (28) of the channel (26) is possible
when the user of the workbench causes relative pivotal movement to occur between the
pair of bars (2) and the pair of brackets (16). It will be apparent that the reason
the arcuate portion (28) has been chosen to subtend a right-angle is to permit the
jaws (14) (and the other jaw supported on the pair of brackets (16) but not shown)
to lie either in the same or orthogonal planes.
[0021] The two end portions of the channel (26) which flank the arcuate portion (28), in
this example linear end stops (30) which are formed tangentially to the arcuate portion
(28), serve both to restrict the travel of the projecting end (20) within the channel
(26) and hence, therefore, to limit the extent of relative pivotal movement between
the pair of bars (2) and the pair of brackets (16). As explained above, the spring
(24) serves to urge the arm (18) in the direction of the arrow shown in Figure 5 and
this translates, when viewing the relationship between the channel (26) and projecting
end (20), into meaning that the arm (18) will be biased by the spring (24) so that
the projecting ends (20) are urged into the end stops (30). Thus, when the projecting
ends (20) are aligned with either end stop (30) (rather than arcuate portion (28))
then, in the absence of any user force against the arm (18) along the longitudinally
extending surface (22) in the opposite direction to the arrow of Figure 5, the projecting
ends (20) will be forced into and held within the end stops (30). In this manner,
the pair of bars (2) and the pair of brackets (16) (and hence their respective jaws)
can be locked into their relative pivotal positions, i.e. lying in the same plane,
or lying in orthogonal planes.
[0022] Referring again to Figures 7, 8 and 9, the relationship between the arm (18) and
the channel (26) and the manner in which they co-operate to enable working of the
present invention will be described. In Figure 7, the pair of bars (2) and the pair
of brackets (16) are lying in the same plane. Thus the jaw (14) carried by the pair
of bars (2) and the jaw (not shown) carried by the pair of brackets (16) are also
lying in the same place.
[0023] From Figures 5 and 7 it can be seen that the arm (18) is biased towards the right
hand side of Figure 7 and because the pair of bars (2) and the pair of brackets (16)
are lying in the same plane, then the projecting end (20) is aligned with the end
stop (30) and is hence urged thereinto. Thus the pair of bars (2) and the pair of
brackets are effectively locked into this position because whilst the projecting end
(20) is constrained within the end stop (30), then no relative pivotal movement between
the pair of bars (2) and the pair of brackets (16) is possible.
[0024] If, however, a user of the workbench applies a force to the arm (18) in the direction
of the arrow A (Figure 7) of sufficient magnitude to overcome the biasing force applied
to the arm (18) by the spring (24), then the arm (18) will move to the left and hence
the projecting end (20) will move out of the end stop (30) and become aligned with
the arcuate portion (28). This can now be seen from Figure 8.
[0025] In this position shown in Figure 8, the user may then effect relative pivotal movement
between the pair of bars (2) and the pair of brackets (16) by moving the pair of bars
(2) upwards in the direction of arrow B. This is only possible because the projecting
end (20) of arm (18) is able to travel within the arcuate portion (28) of the channel
(26). Indeed, this relative pivotal movement may occur freely between either end stop
(30) so long as the projecting end (20) does not align with either end stop and also,
in this event, so long as the force applied to the arm (18) does not cease to act
against and overcome the force applied to the arm (18) by spring (24).
[0026] Referring now to Figure 9, it can be seen that when the pair of bars (2) and the
pair of brackets are lying in orthogonal planes, i.e. when the projecting end (20)
has travelled the length of the arcuate portion (28) from its position in Figure 7
(through 90°), then when the arm (18) is released (in the direction of arrow C) and
the projecting end is aligned with the other end stop (30), the pair of bars (2) and
the pair of brackets are automatically locked into this position. The process may
now be reversed when the user requires the jaws or the bars (2) and brackets (16)
to once more lie in the same plane.
[0027] By referring now to Figure 10, an entire workbench in accordance with the present
invention is shown. In this Figure, the other jaw (15) of the pair (14, 15) is also
shown whereas in all previous figures it was omitted for the sake of clarity. The
workbench will not be described in any detail as it is of well-known construction
to those skilled in the art. The pair of brackets (16) are themselves supported by
a collapsible frame (32) which is coupled at its other end to a base support structure
(34). Those skilled in the art will appreciate that the collapsible frame (32) permits
the entire workbench to be folded for ease of storage when not in use.
[0028] It will be understood by those skilled in the art that the device described above
provides a means by which relative pivotal movement between first and second members
may be achieved easily and by which the members may be selectively locked in either
of two predetermined positions.
[0029] Although in the above the channels (26) have been formed by punching a hole into
the pair of brackets (16), these channels (26) could be equally well formed as recesses
in the material of the brackets (16).
[0030] It will be appreciated by those skilled in the art that although in the above example
the arm (18) is mounted on the bars (2) and the channel (26) is formed on or from
the brackets (16), this is not necessary. They may each equally well be formed on
the other of the bars (2) or brackets (16).
[0031] Although in the above example reference has been made to pairs of bars (2) and brackets
(16), this is only by way of example. It will be understood that the invention is
equally efficacious if a unitary member were to form either or both of these items.
1. A workbench including:
a first support member pivotally coupled to a second support member and wherein one
of the first and second support members is formed with detent-engaging means;
detent means mounted on the other of the first and second support members and co-operable
with the detent -engaging means thereby to selectively permit or prevent relative
pivotal movement between the first and second support members;
characterised in that the detent-engaging means comprises a channel formed in
the said one of the first and second support members, which channel defines first
and second regions, one of which first and second regions allows the detent means
limited movement therewithin and the other of the first and second regions restrains
movement of the detent means.
2. A workbench according to Claim 1 wherein one of the first and second regions of the
channel is substantially arcuate, thereby to cause the detent to follow an arcuate
path in sympathy with the relative pivotal movement between the first and second support
members.
3. A workbench according to Claim 2 wherein the other of the first and second regions
of the channel defines a stop for the detent means thereby to prevent relative pivotal
movement between the first and second support members.
4. A workbench according to Claim 3 wherein the stop is formed tangentially to the arcuate
region of the channel.
5. A workbench according to Claim 3 or Claim 4 wherein the stop is substantially linear.
6. A workbench according to any one of the preceding claims wherein there are two of
the other of the first and second regions, these two of the other of the first and
second regions flanking the first region.
7. A workbench according to any one of the preceding claims wherein the detent means
is biased towards one of the first and second regions.
8. A workbench according to Claim 7 when appendant to any one of Claims 3 - 6 wherein
the detent means is biased towards the other of the first and second regions.
9. A workbench according to Claim 8 wherein the detent means is biased by way of a spring
member.
10. A workbench according to any one of the preceding claims wherein the detent means
comprises a manually operable arm.
11. A workbench according to Claim 10, when Claim 6 is appendant to Claim 3, wherein the
manually operable arm tends to be urged towards the or each stop by the spring member.
12. A workbench according to Claim 11 wherein when urging of the arm coincides with the
arm being positioned within the channel directly over the or each stop, then the arm
is retained within said the or each stop hence preventing relative pivotal movement
between the first and second support members.
13. A workbench according to any one of the preceding claims wherein the channel is formed
as a recess within said one of the first and second support members.
14. A workbench according to any one of Claims 1 - 12 wherein the channel is formed as
a hole within said one of the first and second support members.
15. A workbench according to any one of the preceding claims wherein the first and second
support members each comprise a pair of supports.
16. A workbench according to any one of the preceding claims wherein the first and second
support members each support a pair of jaws of the workbench.
17. A workbench according to any one of the preceding claims wherein the first and second
support members each are formed on respective legs of the workbench.
18. A workbench substantially as hereinbefore described and with reference to the accompanying
drawings.