GB2180587A - Push-button combination lock - Google Patents

Abstract

The sliding member 4 which is released on depression of the correct combination of buttons is not in direct contact with the latch 1 which engages the hook 2 of a padlock so that stress on the hook is not transmitted to the sliding member thereby making it difficult to find the correct combination. On release of the sliding member 4, a second sliding member 5 which engages the latch can be released from engagement with the latch. 0n release of the second sliding member a spring-loaded intermediate element 3 which has a shaped end in engagement with the latch can be depressed to cause disengagement of the latch from the hook. The push buttons are held in the depressed position by spring-loaded checks 94 mounted on a sliding plate 95 which can be moved on depression of a return button 8 to cause simultaneous release of all the push buttons. The characters corresponding to the combination buttons are coated with phosphorescent material so as to enable one to discriminate between the characters in the dark. <IMAGE>

Description

SPECIFICATION An improved push-button type combination lock This invention relates to an improved combination lock of push-button type.

Before entering our topic, I must first define three terms which are to be used throughout the specification and the claims. Please refer to the inset of Fig. 1. The three dimensions of a lock are respectively defined as H-, W-, and T-direction, wherein H refers to the "height direction", W refers to the "width direction", and T, the "thickness direction".

The conventional combination lock of pushbutton type, comprises a plurality of, say typically ten, buttons. Each button is substantially an elongate column of which the length is slightly greater than the thickness of the lock.

Thus when one end of a button is pressed down in T-direction, its another end will emerge from the opposite side of the lock.

Each column is provided with a slot. The slot can occupy either one of the two positions on a column. A sternum-like sliding member is disposed to slide a short distance along the H-direction of the lock to allow one to unlock the lock. Said sliding member is provided with a plurality of projections extending in W-direction, and therefore, a plurality of corresponding recesses. The shape of the recess corresponds to the contour of the column. Only when all the ten slots are located in alignment in the same level as the sliding member can the latter make said sliding in H-direction; otherwise the projections will be stopped by at least one column. The two positions of slots are such that a slot is in alignment with a projection when a button is either pressed down or not.Thus with the two states of each button, "high" and "low", we have the tenth power of two (210=1024), namely more than 1000 combinations, in which only one is the correct code to unlock the lock.

So far as the latch is concerned, it is similar to those known padlocks of cylinder locks with a hook. A latch is disposed to slide a small distance along the width of the lock (Wdirection) between a locking position where it engages with a slot of a hook and an unlocking position where it is not in engagement with the hook. When the buttons are set in the correct combination, the sliding member can slide a small distance the release the latch, which in turn releases the hook, so that one can pull out the hook in H-direction and unlock the lock. When one pushes the hook back in position and locks up the lock, both the latch and the sliding member return to their original positions. Both the sliding member and the latch are spring-loaded so as to bias them toward one of their two states.The hook is preferably spring-loaded in a manner such that it is resiliently pulled toward its locking positition, so that the hook will not automatically spring up when the buttons are correctly pushed. This can make an unauthorized person attempting to try each combination more difficult to find the correct combination.

However, such a combination padlock suffers several advantages as follows: Firstly, the lock presents little problem to an adroit lock-picker. One can exert a steady force on the lock, urging the hook of a locked padlock in H-direction. Meanwhile he tries to push the buttons one by one under the stressed condition of the hook. The stress on the hook can be directly transmitted through the latch to the sliding member, and therefore transmitted to the incorrectly positioned columns whose slots do not in alignment with the sliding member. Accordingly, if the slot of a column is not registered to the corresponding projection of the thus stressed sliding member and the column will undergo a transversal stress, which locks up a slight resistance when one pushes the button.The difference of the resistance of a correctly positioned button and an incorrectly positioned one is very small, but can still be distinguished by an adroit person. Hence an old hand can find its correct combination within minutes without special tools.

Secondly, since each button forms as an integral column, which is retained and slidable in T-direction in a path opening on the two opposite side so that its ends may emerge from either side of the lock, if the lock is not strong enough, one can hold the lock against its background (for example, the doorside), and use a hammer to inflict a blow at the emerged ends of the buttons to cause the fracture or distortion of the columns. As a result, the lock may be damaged, forced to open, or internally jammed by the broken columns so that it can no longer be unlocked.

Moreover, when one is locking up such a lock, he has to reset all the previously depressed columns from the opposite side into their high position. This is more or less convenient.

Thirdly, one may have difficulty in reading the number of the buttons in the dark, and has to fumble for the buttons.

Accordingly, it is the object of this invention to provide an improved combination lock of pushing button type, whereby the aforesaid drawbacks are obviated.

The solution to the first problem is to provide an intermediate element between the sliding member and the latch, so that stress on the hook will not be transmitted to the sliding member. Thus, even an adroit lock-picker finds it difficult to find out the combination.

The solution to the second problem is to provide an improved column. When pushed down at one end, its other end does not emerge from the opposite side of the lock.

Said other end is spring-loaded and the button can be retaained at "low" position when pushed down. There is further provided an additional releasing button which can release the retention of all the pushed buttons to reset them to their "high" position. Since a hit at one end of the column does not cause the opposite end to emerge from the opposite side to act on the background surface, the lock is not so easily destroyed by violence.

The solution to the third problem is to apply a phosphorescent substance to the characters each of which corresponds to each button.

Numerous other features and advantages will be apparent when read in connection with the accompanying drawings, in which coordinates are given to show the orientation of each element.

Figure 1 is a perspective view of a pushbutton type combination lock according to this present invention; Figure 2 is a fragmentary perspective view of Fig. 1; Figure 3A shows the relationship between the latch, the first intermediate element and the hook wherein said first intermediate element is pressed to make said latch disengage from said hook; Figure 3B shows the relationship between the latch, the first intermediate element and the hook wherein said first intermediate element is released to make said latch engage with said hook; Figure 4A and 48 show the relationship between the second sliding member and the latch; Figure 5A to 5C show the relationship between the latch, the first sliding member, the second sliding member, the second accessory buttons, and the hook wherein only one of the second accessory buttons is illustrated for simplicity;; Figure 6 shows two types of the combination push-buttons; Figure 7A and 7B show the relationship between a check means and a push-button; and Figure 8A and 8B show the relationship among the sliding piece, the check means, the push-button, the linking rod and the third accessory button.

As stated before this invention differs with conventional push-button combination locks in three respects: (A) an indirect mechanical connection between the latch and the sliding member, (B) an improved push-button mechanism, and (C) phosphorescent characters.

They will be separately described hereinbelow: A. Indirect connection between latch means and sliding member.

Referring to the drawings and in particular to Figs. 2 and 3 thereof, the spring-loaded latch (1) according to this invention is resiliently retained in a path in T-direction to move a short distance to engage into a notch (21) on a hook (2). To avoid the transmission of the stress from the hook to sliding member (4), the sliding movement of the latch means and the sliding member (4) must take place in two different (preferably parallel) planes. A spring-loaded intermediate element (3) is disposed between the latch (1) and the sliding member (4), which can move a small distance in perpendicular to said latch (1). Only when the correct buttons are pressed can the sliding member (4) be released. Also, only when the sliding member (4) is released can be intermediate element (3) be released.And only when the intermediate element (3) is released can the latch (1) be released to unlock the lock.

As stated before the role of the intermediate element (3) is to prevent the sliding movements of the latch (1) and the sliding member (4) from occurring in the same plane. Thus a stress on the hook (2) can only be transmitted through the latch (1) to the intermediate element (3), and is intercepted there. A displacement of the intermediate element (3) must cause the latch (1) to move toward the hook (2) or away from it. For this purpose, the latch (1) has an elongate slot (11) extending along the T-direction and a recess (14) formed in the W-direction, whereas the intermediate element (3) has a shaved lower end (31) which can be inserted into the slots (11). Referring to Fig. 3A, to offer the latch (1) a tendency to move toward its locking position, the latch (1) is spring-loaded to make it resiliently biased toward its locking positions.The upper end of the intermediate element (3) emerges out of the housing of the lock in form of a first accessory button (32) (see Fig.

1). Referring to Fig. 3B, when it is pressed in W-direction by the insertion of the shaped end (31) of intermediate element (3) into the slot (11) thereof, so the latch (1) is pushed to its locking position and engaged with the notch (21) of the hook (2).

With reference to 4A and 4B, only the second sliding member (5) having a spring (51) disposed thereon is directly in contact with the latch (1). The second sliding member (5) directly contacts the latch (1) and carries out a like function to the first sliding member (4).

This ensures a still better insulation of stress transmission. The second sliding member (5) does not have any transverse projection and its sliding movement is independent of the positions of the combination buttons. But the second sliding member (5) can only slide away from the recess (14) when the first sliding member (4) is released. Practically, the lock is provided with a pair of second accessory buttons (6) (See Fig. 1), which can only be pressed down when the first sliding member (4) is released. And only when the second accessory buttons (6) are pressed can the second sliding member (5) be retracted from the recess (14) of said latch (1) to allow one to press down the first accessory button (32) to unlock the lock.

Figs. 5A to 5C show the relationship among the first and second sliding members (4) (5) and said second accessory buttons (6) wherein only one of the second accessory buttons (6) is shown for simplicity.

Each second accessory button (6) has a slot (61) and a surrounding annular groove (62).

The second sliding member (5) is positioned on the first sliding member (4). Referring to Fig. 5A, when the combination buttons are not correctly pressed, one end of the first sliding member (4) is forced by certain incorrectly positioned buttons (9a) (only one is shown) and remains in the groove (62) of each second accessory button (6) so that the accessory button (6) cannot be pressed down.

Meanwhile the second sliding member (5) forces the latch (1) to remain in engagement with the notch (21) of the hook (2); thus the lock remains in locked state. Referring to Fig.

5B, when the combination buttons (9a) are correctly pressed (only one is shown), the first sliding member (4) is no longer stopped by any combination button, and is resiliently biased to slide away from the groove (62) of each secondary accessory button (6). Now one can push the second accessory button (6) down, so that the second sliding member (5) is in alignment with slot (61) thereof.Referring to Fig. 5C, then the first accessory button (32) (not shown) can be pressed down to make the latch (1) disengage from the notch (21) of the hook (2) and then to unlock the lock, and since the depression of button (32) will cause the latch (1) to move up in T-direction and in turn cause the recess (14) to move up, the end of the second sliding member (5) is pushed out of the recess (14) against the resilience of its springs, and the opposite end of second sliding member (5) engages into the slot (61). A retaining means is provided to retain the second accessory button (6) in its depressed position. The retaining means is a spring-loaded check (94a) which bites into a groove (63) at the lower end of said second accessory button (6).

Thus, in this modification, to unlock the lock, one has to push the correct combination keys, then push said two second accessory buttons (6) simultaneously (only one is shown in Fig.

5A to 5C), so that the first accessory button (32) can be pressed down to unlock the lock.

One must keep depressing the first accessory button (32) until the hook (2) is sprung out.

Practically, the depressed buttons (6) simultaneously release when one resets all the depressed combination buttons (9a). This will be discussed later. Having thus clearly described the indirect mechanical connection between the latch (1) and the sliding members (4) and (5) in detail, now I will describe the improved push-button mechanism hereinafter.

B. Improved push-button mechanism This mechanism consists in two aspects: (a) When a combination button is pressed down, it must be retained in depression position; without that the opposite end of the clumn (of which one end serves as the combination button) will emerge from the opposite side of the lock housing.

(b) There is provided a third accessory button (8) or return button (See Fig. 1). When the return button (8) is pressed, all the depressed combination buttons will be released and resume their original positions.

It is very simple to achieve the two functions using known means. The lower end of a push-button, i.e. the end opposite to its pushing end, is biased by a spring which resiliently pushes it upward to its high position. There is provided retaining means (94) which can engage with the groove (93) of the push-button and retain said push-button in its- depressed position. There is further provided releasing means which releases the retention of said retaining means so that a depressed button may resume its original high position.

Like the conventional press button type padlock, this invention comprises a plurality of combination press buttons. Referring to Fig. 6, depending on the position of their slots (92), there are two kinds of press buttons (9a) and (9b). The slot (92) of (9b) is in alignment with the projection (41) of the first sliding member (4) when the button is not depressed, while the slot (92) of (9a) is in alignment with the projections (41) when depressed. However, unlike the columns of the conventional press button padlock, each of the columns (9a) or (9b) has an annular groove (93) at its lower end. There are provided corresponding locking means for each column (9a) or (9b). Referring to Figs. 7A and 7B, the locking means is a spring-loaded check (94).When a column, for example, column (9a), is depressed in T-direction, the check (94) is pushed aside in Wdirection by the end of column (9a) and then resiliently returns and bites into the annular groove (93) of the column and retains the latter in depressed position. Referring to Figs.

8A and 8B, all the checks (94) are mounted on a sliding piece (95) which can be actuated by the return button (8) to slide a small distance in H-direction. Each check (94) is integrally formed on the sliding piece (95), and is loaded with a spring (953) to achieve its function. The sliding piece (95) has two slots (951) running in H-direction to allow the columns to pass through. The sliding piece (95) is biased by spring means (952) to remain in the position where the depressed combination buttons can be retained by the checks (94).

When one presses the return button (8) the sliding piece (95) is fored to move a small distance in H-direction thus all the depressed buttons are released. There are many known ways to achieve this function. For example, the sliding piece (95) can be easily pushed in H-direction by linking rod (81) which is driven to rotate along the direction of arrow by pressing the return button (8) in T-direction.

Furthermore, the checks (94a) for second accessory buttons (6) are preferably provided at the sliding piece (95).

Thus when one resets the depressed combination buttons (9a), he meanwhile releases the second accessory buttons (6). However, when the sliding member (95) is pushed to release the depressed buttons (9a), the second accessory buttons (6) must be released before the releasing of the depressed combination buttons (9a). This is self-evident, since the first sliding member (4) is pushed by the rising columns against its biasing spring to resume in engagement with groove (62). If the second accessory buttons (6) rise too late, this desired procedure will not occur smoothly. This is only a matter of engineering design, and can be easily achieved by proper dimensioning.For example, in this case, the width (X) of the check (94a) is arranged to be narrower than the width (Y) of the check (94) thereby when the sliding member (95) is pushed to release the depressed buttons (9a) the second accessory buttons (6) can be released before the releasing of the depressed combination buttons (9a).

Referring to Figs. 6, 7A and 7B, it is noteworthy that the lower end portion of each column (9a) or (9b) has a bevel lower margin and a flat upper side. This structure facilitates it to push away the check, when the column is pushed downward, and then securely held by the check (94) in place. On the other hand, the groove has a bevel upper margin and a flat lower face to match the shape of the check (94). Each second accessory button (6) is provided with like means for the same purpose. Referring Figs. 5A to 5C, the lower end of each second accessory button (6) is similar to that of a column (9a) or (9b) as shown in Fig. 6. It has a bevel lower margin.Corresponding to the groove (93) it also has a like groove (63) so that when it is pressed down, it can be retained in place by a corresponding check (94a) on the sliding piece (95), and when one pushes return button (8) to shift sliding piece (95), it is also released and resiliently rises to its first position.

Referring to Figs. 5A to 5C, when the correct combination buttons (9a) are depressed, the first sliding member (4) resiliently slides off from the groove (62) of said second accessory buttons (6) so that one can press down the second accessory buttons (6), which are then retained in its depressed (second) position by said checks (94a) thereof.

Now one can push down the first accessory button (32) (and he must keep on pressing it until the hook is released). When he keeps on depressing the button (32) the latch (1) is forced to remain in its second position, and the second sliding member (5) is driven into the slots (61) of said second accessory buttons (6). Now the hook (2) will be sprung out thereby opening the lock. The first accessory button (32) resiliently rises when he releases it. Thus, the latch (1) returns to its locking position. The spring-loaded second sliding member (5) is resiliently pushed back into the recess (14) of the latch (1), and leaves the slot (61) thereof. But the second accessory buttons (6) are still retained by its retaining means, and thus remain in their depressed state.When one desired to re-lock the lock, he must push the return button (8) at first to "reset" all the depressed buttons (including the second accessory buttons) and then all the buttons rise to their unpressed position.

Note that the projections (41) of first sliding members (4) are partially received in the slots (92) of their corresponding columns when the first sliding member (4) is in its second position. Thus when one pushes the return button (8), all the depressed buttons (9a) rise and push their corresponding projections away, thus pushing the first sliding member (4) into the grooves (62) of said second accessory buttons (6) hence locking the lock. If desired, a few arbitrary combination button can be depressed. Since the first sliding member (4) must be pushed by the rising of the depressed columns into grooves (62) thereof, the slot of each column (9a) preferably has a bevel or rounded lower margin.

C. phosphorescent characters The characters corresponding to the combination buttons (9a) and (9b) are coated with phosphorescent material so as to enable one to discriminate the characters in the dark.

The combination lock according to this invention can be used in various ways for doors as well as cars.

Claims (8)

1. A push-button type combination lock comprising a flat housing, a hook retained in said housing to move in the direction of the height of the lock, hereinafter defined as Hdirection, said hook having at least one notch along its length, a plurality of buttons in form of elongate columns, said columns being aligned in at least one row in said H-direction, each of said column being oriented in the direction of the thickness of said padlock, which is hereinafter defined as T-direction, and being retained to move in said T-direction between a first and a second column-positions, each column having a slot which occupies one of two definite sites on said column, springloaded latch means retained to move between first and a second latch-positions, a first spring-loaded, flat, elongate sliding member retained in said housing to move in said Hdirection between first and second first-sliding-member-positions, which is hereinafter referred to as first sliding member, said first sliding member being oriented in said H-direction, and at least one side of said first sliding member being provided with projections corresponding to said columns, said projections extending in the direction of the width of said padlock, which is hereinafter defined as direction;; said columns and said first sliding member being such that when a column is in one of its two column-positions, its slot is in alignment with a corresponding projection of said first sliding member in H-direction and allows the projection to pass through said slot so that said sliding member can shift from a first first-sliding-member-position to a second first-sliding-member-position, and when said column is in the other column-position where its slot is not in alignment with the corresponding projection in H-direction, the latter will be hindered by the column so that the first sliding member slide in H-direction and remains in its first first-sliding-member-position.

said first-sliding member and said latch means being such that when said first-sliding member is in its first first-sliding-member position, said latch means is held in its first latchposition and cannot slide in T-direction, and when said first sliding member is in its second first-sliding member position, said latch means can slide in T-direction to its second latchposition; said latch means and said hook being such that when said latch means is in said first latch-position, said hook is held by said latch means where the lock is in locked state and the latch means engages into the notch of the hook, and when said latch means is in said second latch-position, it is not in engagement with the notch of said hook and the hook is no longer held and can shift in the H-direction where the lock is in unlocked state;; spring means for the aforesaid elements being such that said first sliding member is resiliently biased toward its second first-sliding member position, and said latch member is resiliently biased toward its first latch position; a pair of second intermediate elements being oriented in T-direction and retained in said lock to slide in T-direction between first and second second-intermediate-element-positions; a second sliding member being oriented in H-direction and retained in said lock to slide in H-direction between first and second secondsliding-member-positions;; said second intermediate elements and said first sliding member being such that when said first sliding member is in its first first-slidingmember-position, said second intermediate elements are restricted in their first secondintermediate-element-position and cannot make said sliding, and when said first sliding member is in its second first-sliding-member-position, said second intermediate elements can slide to their second second-intermediate-element-position;; said second intermediate elements and said second sliding member being such that when said second intermediate elements are in their first second-intermediate-element-position, said second sliding member is restricted in its first second-sliding-member-position and cannot make said sliding, and when said second intermediate elements are in their second second-intermediate-element-position, said second sliding member can make said sliding to its second second-sliding-member-position; said second sliding member and said latch means such that when said second sliding member is in its first second-sliding-memberposition, said latch means is restricted in its first latch-position and cannot make said sliding, and when said second sliding member is in its second second-sliding-member-position, said latch means can make said sliding in Tdirection to its second latch position;; the padlock being characterized in that it comprises at least an intermediate element interposed between said latch means and said first sliding member so that said latch means and said first sliding member are not in direct contact with each other and the sliding movements of said latch means and said first sliding member do not occur in the same plane, said intermediate element being retained in said housing to slide in W-direction between a first intermediate-element position and a second intermediate-element position, said first sliding member and said intermediate element being such that when said first-sliding member is in its first first-sliding-member-position, said intermediate element is held in its first intermediate-element-position and cannot make said sliding in W-direction, and when said first-sliding-member is in its second first-sliding-member-position, said intermediate element can make said sliding in W-direction to reach its second intermediate-element-position; said intermediate element and said latch means being such that when said intermediate element is in its first intermediate-element position; said latch means is held in its first latch-position and cannot slide in T-direction, and when said intermediate element is in its second intermediate-element-position, said latch means can slide in T-direction and reach said second latch-position.

2. The push-button type lock according to Claim 1, wherein the latch means is provided with an elongate slot extending in T-direction and a recess facing and second sliding member, said recess having a shaped portion, said latch means having spring means which tend to bias said latch means toward said hook, and said intermediate element having one end emerging outside of the housing of said lock as an accessory button, and its other shaved end for extending into the slot of said latch means.

3. The lock according to Claim 2, wherein one end of said second sliding member is driven into the recess of said latch means to restrict the sliding of said latch means.

4. The lock according to Claim 1, wherein one end of each said second intermediate element emerges outside of said lock in form of a second accessory button, while its other end is provided with two recesses, the first recess being in alignment with said first sliding member and allows the latter to be inserted therein to bring the latter into its first firstsliding-member-position when said second intermediate elements are in their first secondintermedia-element-position, the second recess being in alignment with said second sliding member and allowing the latter to be pushed thereinto when the second intermediate elements are in their second second-intermediate element position.

5. The lock according to Claim 1, further comprising retaining means to retain the depressed columns and second intermediate elements in their depressed positions respectively corresponding to said second column-position and said second second-intermediate-elementpositions, and a common releasing means to release all the depressed columns and second intermediate elements to resume their unpressed positions respectively corresponding to said first column position and said first second-intermediate-element-position with a single action.

6. The lock according to claim 5 wherein said retaining means comprising resilient means which cooperate with one end of each of said column so that the latter can be secured in place when depressed, and said releasing 5 means comprising a shifting means to shift said retaining means in H-direction.

7. The lock according to Claim 6, wherein the sliding piece is also provided with further checking means for holding said second intermediate members in their second second-intermediate-member-position, which are releasd when said shifting means is shifted to release the depressed columns; said retaining means, the shifting member and the check means being such that releasing of the second intermediate member precedes the releasing of the depressed columns.

8. A push-button type combination lock substantially as hereinbefore described with reference to and as shown in the drawings.